ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (11,487)
  • Springer  (11,487)
  • 2020-2022  (2,764)
  • 1995-1999  (8,723)
  • Process Engineering, Biotechnology, Nutrition Technology  (11,487)
Collection
  • Articles  (11,487)
Source
Keywords
Publisher
Years
Year
Journal
Topic
  • 1
    Electronic Resource
    Electronic Resource
    The lysins of bacteriophages infecting lactic acid bacteria (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 1-6 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  This short review highlights the complete absence of literature on lysins of bacteriophages infecting species like S. salivarius subsp. thermophilus, Pediococcus and Leuconostoc species, L. helveticus, L. acidophilus, L. plantarum and L. brevis, which are also widely used in the dairy industry. The lysins described share some similar biochemical characteristics: optimal pH and temperature, site of hydrolysis inside the peptidoglycan, and some activators and inhibitors. The clon- ing of the genes encoding these lysins only began in the last few years and four of them have been completely sequenced. In the future, these lysin genes could be interestingly compared to the host autolysin(s) gene(s). By contrast, the passage of phage lysins through the cytoplasmic membrane of the host cell in order to reach the peptidoglycan (via a signal sequence or the presence of a holin) seems not to be clearly resolved. The presence of a second open-reading frame upstream from the gene of the lysin, enabling a putative holin to be encoded, has already been suggested. No doubt our ever increasing knowledge about bacteriophage genome organization will help to elucidate this question. Meanwhile the obtention of a Lactococcus strain with an autolytic phenotype, using a bacteriophage lysin gene, as well as the successful use of purified PL1 lysin to obtain protoplasts of L. casei encourage us to continue to explore the field of bacteriophage lysins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050360
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Influence of stringent and relaxed response on excretion of recombinant proteins and fatty acid composition in Escherichia coli (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 89-92 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  In contrast to stringent (relA+) cells of Escherichia coli, relaxed (relA) cells excreted recombinant proteins (β-lactamase, interferon α1) into the culture medium during amino acid limitation. Comparative analyses of overall fatty acid composition in relA+ cells and relA cells were performed and revealed that, in wild-type cells, drastic alterations occurred during the stringent response. The portion of saturated fatty acids (C16 : 0) and the fractions of cyclopropane fatty acids (C17cyc and C19cyc) increased whereas the portions of unsaturated fatty acids (C16 : 1 and C18 : 1) decreased. In cells of the relaxed mutant, no significant changes in the overall composition of the fatty acids were observed after the onset of amino acid limitation. These results indicate that a change in fatty acid composition of membrane lipids after starvation of cells may be responsible for the prevention of loss of cellular proteins into the culture medium in stringent controlled cells of Escherichia coli.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050375
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Growth behaviour and glucoamylase production by Aspergillus niger N402 and a glucoamylase overproducing transformant in recycling culture without a nitrogen source (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 109-116 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  When wild-type Aspergillus niger N402 and a glucoamylase-overproducing transformant were grown in recycling culture without a nitrogen source, hyphal tip extension and glucoamylase production still occurred, but overproduction of glucoamylase by the transformant strain stopped. The mycelium retained a low metabolic activity. Light micrographs of mycelial samples showed that some hyphae were broken at their tip and partially empty, while after continuing recycling fermentation for more than 500 h many small and empty pieces of broken mycelium could be found. A model has been developed to calculate the mycelial growth and death rates. The mycelial death rate just exceeded the mycelial growth rate and as a consequence the amount of biomass in the fermentor vessel slightly decreased. It is concluded that the cytoplasmic contents of broken mycelial threads were released into the medium and acted as a nitrogen source for the growing parts of the mycelium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050378
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Mixed photo-cross-linked polyvinyl alcohol and calcium-alginate gels for cell entrapment (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 10-17 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Living cells may be immobilized by gel entrapment under very mild conditions. The ionotropic gelation of alginate with bivalent cations such as Ca2+, as well as photo-induced gelation of polyvinyl alcohol (PVA) bearing photosensitive stilbazolium (SbQ) groups, are procedures that are compatible with most bioactive materials. In the search for more stable and stronger alginate gel beads, experiments have been carried out to investigate mixed gels from alginate and PVA-SbQ. The swelling capacities, diffusion properties, and potential toxic effect of the binary gel beads have been evaluated. The gel beads of selected PVA-SbQ/alginate mixtures were applied successfully as carriers in a denitrification process with continuous feeding of unsterilized water medium. Under such conditions, the purely synthetic PVA-SbQ network is expected to have a longer lifespan than a natural biopolymer such as alginate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00170615
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Analysis of Penicillin V biosynthesis during fed-batch cultivations with a high-yielding strain of Penicillium chrysogenum (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 123-130 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Metabolites (both intra- and extracellular) involved in penicillin biosynthesis were measured during fed-batch cultivations with a high-yielding strain of Penicillium chrysogenum. The fed-batch cultivations were carried out on a complex medium containing corn steep liquor. Three distinct phases were observed: (a) a rapid growth phase where free amino acids present in the medium are metabolized, (b) a linear growth phase, and (c) a stationary phase. The specific penicillin production (r p) is initially high and, during the rapid growth phase, it increases slightly. During the linear growth phase r p is approximately constant [4–6 mg penicillin V (g dry weight)-1 h-1 depending on the operating conditions], whereas it decreases during the stationary phase. During the cultivations the tripeptide Aad-Cys-Val (the first metabolite in penicillin biosynthesis) and 8-hydroxypenillic acid (formed by carboxylation of 6-aminopenicillanic acid, 6-APA) were found to accumulate in the medium, whereas the concentrations of isopenicillin N and 6-APA were found to be approximately constant and low. About 3% of the Aad-Cys-Val formed in the first step of the penicillin biosynthetic pathway is lost to the medium and 4% of the isopenicillin N formed in the second step of the pathway is lost as extracellular isopenicillin N, 6-APA or 8-hydroxypenillic acid. Also the cyclic form of α-aminoadipic acid, 6-oxo-piperidine-2-carboxylic acid, was found to accumulate in the medium and it was found to be formed in an approximately constant ratio to penicillin V of 6 mol/100 mol.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050380
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Biodegradation of 2-chloroethanol by freely suspended and adsorbed immobilized Pseudomonas putida US2 in soil (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 143-149 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The degradation of 2-chloroethanol by Pseudomonas putida US2 was investigated in batch, repeated batch and continuous cultures especially in a packed-bed fermenter with sand. The degradation of 2-chloroethanol was connected with a release of protons, which led to a decrease of the pH in the medium. Higher initial concentration than 25 mM 2-chloroethanol were not degraded completely because they entailed a decrease of the pH to 5.0, which inhibited further growth and degradation. P. putida US2 showed a typical repression of catabolites and diauxic growth with succinate as cosubstrate. The addition of succinate as a second substrate caused a decrease in degradation of 2-chloroethanol. Activated sludge added to adsorbed cultures in a continuous fermentation did not lead to a decrease in metabolic activity. After 2 weeks of continuous cultivation the specialized strain could be retained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050383
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Kinetics of bio-oxidation of a medium comprising phenol and a mixture of organic contaminants (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 165-170 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The kinetics of bio-oxidation by a microbial ensemble of a model mixture of contaminants that mimicked the ground-water pollution plume at an existing contaminated site was investigated. Phenol at 50 mg/l and a mixture of ten organic contaminants (MOC) (benzene, tetrachloromethane, trichloroethylene, toluene, o-xylene, 1,4-dichlorobenzene, o-cresol, nitrobenzene, naphthalene and 2,6-dichlorophenol) at individual concentrations ranging from 150 μg/l to 600 μg/l were the components of the model mixture. The microbial ensemble consisted of at least three Pseudomonas spp. isolated from the polluted site. Patterns of oxygen uptake rate (OUR) for the oxidation of phenol alone and with added MOC were treated mathematically. The values for kinetic parameters that gave the best fit to the data were respectively 11.29 and 15.03 ml O2 h-1 (mg protein)-1 for the OUR maximum (OURmax), 75.89 mg/l and 33.66 mg/l for the saturation constant (K s), 105.92 mg/l and 36.44 mg/l for the inhibitor constant (K i), and 89.66 mg/l and 35.02 mg/l the substrate minimum inhibitory concentration (S mic). This study also scrutinised interference between the two components of the model mixture of contaminants (phenol and MOC) on the basis of variations in kinetic patterns. MOC was shown to be toxic at milligram per litre levels. The microbial ensemble increased phenol oxidation in response to MOC, possibly to obtain the energy to overcome this toxic effect. This was indicated by an acceleration of phenol oxidation in response to increasing concentrations of MOC and higher OURmax for oxidation of phenol in the presence of MOC. The toxicity of MOC also resulted in enhanced vulnerability of the microbial ensemble to a phenol inhibitory effect, indicated by the diminution of K i and S mic. The microbial ensemble showed high resistance to inhibition by the sole presence of phenol possibly because of adaptation to toxic features of MOC during the processes of enrichment and cultivation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050386
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Enhanced anaerobic degradation of benzene by enrichment of mixed microbial culture and optimization of the culture medium (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 178-187 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  A heterogeneous mixed culture, originally collected from two different sources, namely cow-drug and sludge from the city waste-water treatment plant, was grown in mineral medium containing 1% glucose and then adapted on benzene as the carbon and energy source. Under anaerobic conditions benzene was degraded via benzoic acid as a major intermediate in the benzene degradation pathway. The degradation rate of benzene was improved stepwise by the number of enrichments and optimization of the culture medium. The effects of microaerobic conditions and/or physicochemical treatment with H2O2 prior to anaerobic degradation were studied with respect to variations in benzene degradation rate, growth of biomass and gas composition. It was noticed that the amount of gas produced is less than the theoretical value expected and the percentage of methane in the product gas was very small (3%–3.5%). The reason for this is not well understood but it is presumed that the major group of benzene-degrading bacteria present in the culture medium are sulphate reducers and the mixed consortium is unable to degrade certain complex aromatic intermediates in the benzene degradation pathway under the experimental conditions. For an actual explanation of the situation arising in this study, further investigations must be carried out. However, the mixed culture is capable of oxidizing benzene more rapidly to intermediate compounds and also partly into gas under the culture conditions, compared to the published data for the anaerobic degradation of benzene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050388
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Oxygen effect on batch cultures of Leuconostoc mesenteroides: relationship between oxygen uptake, growth and end-products (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 117-122 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Growth and lactose metabolism of a Leuconostoc mesenteroides strain were studied in batch cultures at pH 6.5 and 30° C in 10 l modified MRS medium sparged with different gases: nitrogen, air and pure oxygen. In all cases, growth occurred, but in aerobiosis there was oxygen consumption, leading to an improvement of growth yield Y X / S and specific growth rate compared to anaerobiosis. Whatever the extent of aerobic growth, oxygen uptake and biomass production increased with the oxygen transfer rate so that the oxygen growth yield, Y X / O 2, remained at a constant value of 11 g dry weight of biomass/mol oxygen consumed. Pure oxygen had a positive effect on Leuconostoc growth. Oxygen transfer was limiting under air, but pure oxygen provided bacteria with sufficient dissolved oxygen and leuconostocs were able to consume large amounts of oxygen. Acetate production increased progressively with oxygen consumption so that the total molar concentration of acetate plus ethanol remained constant. Maximal Y X / S was obtained with a 120 l/h flow rate of pure oxygen: the switch from ethanol to acetate was almost complete. In this case, a 46.8 g/mol Y X / S and a 0.69 h-1 maximal growth rate could be reached.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050379
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Biodegradation of 2-sulfonato fatty acid methyl ester (α-SFMe): Identification of microorganisms isolated from activated sludge and their capability for degrading α-SFMe (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 379-382 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Three bacterial strains, A, B and C, were isolated from activated sludge as 2-sulfonato-fatty-acid-methyl-ester (α-SFMe)-degrading microorganisms. From the results of morphological, physiological and biochemical studies, and analyses of 16S rRNA gene sequences, isolate A was identified as Agrobacterium tumefaciens while B and C were Pseudomonas putida, respectively. To demonstrate their capability for the ultimate biodegradation of α-SFMe, the degradation kinetics have been investigated using C14-α-SFMe and 2-14C-labeled C16-α-SFMe. The biodegradation was determined by measuring dissolved organic carbon (DOC) and released SO4 2−, in the shake-culture test, and evolved 14CO2 in the modified Organisation for Economic Co-operation and Development (OECD) test. In the shake culture test with C14-α-SFMe, DOC removal was progressive throughout the test. Liberation of inorganic sulfate started after DOC removal and then rapidly increased. During the 14CO2 evolution tests, the mineralization of radiolabeled carbon started quickly and reached about 80% of the initially added radioactivity at the end of the tests. The results obtained indicated that all of the isolates had the capability for ultimately degrading α-SFMe through the oxidation of the alkyl carbons and desulfonation (cleavage of the C-S linkage).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00172843
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Effect of perfluorodecalin as an oxygen carrier on actinorhodin production by Streptomyces coelicolor A3(2) (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 206-210 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Perfluorodecalin, a perfluorocarbon (PFC), was used in this investigation as a dissolved oxygen carrier in the media of Streptomyces coelicolor cultures. The effects of different concentrations of PFC, PFC emulsified with pluronic F-68 and pluronic alone were investigated in the shake-flask cultures using both defined and complex media. In the defined medium with PFC alone, the maximum biomass and actinorhodin concentrations and the volumetric substrate consumption rates increased with increasing PFC concentration. They decreased dramatically, however, when the PFC concentration exceeded 50% (v/v). Emulsifying the PFC with pluronic F-68 resulted in a significant increase in antibiotic concentration while growth was unaffected. The inclusion of more than 4 g/l pluronic alone in the fermentation medium inhibited the growth. In the complex medium with 40% (v/v) PFC, although the final antibiotic concentration was unaffected, the onset of actinorhodin accumulation was 2 days earlier than that in the control. It was demonstrated that PFC and emulsified PFC did not have any deleterious effects on S. coelicolor cultures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050391
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Fed-batch biotransformation of β-ionone by Aspergillus niger (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 222-227 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Aspergillus niger IFO 8541 was found to be an efficient biocatalyst for the biotransformation of β-ionone into hydroxy and oxo derivatives. The reaction had to be carried out with an inoculum made of about 4×107 fresh spores/l and with a preliminary growth period giving at least 3 g/l biomass. The fungus developed in the form of pellets when cultivated as free mycelium; entrapment of the microorganism in calcium alginate beads was an efficient way to mimic this feature in an aerated, stirred bioreactor. The biotransformation was carried out using a fed-batch mode of operation involving sequential precursor addition. β-Ionone stopped the fungal growth and was converted into metabolites only when the carbon source remained present in the medium; it was fully oxidized after sucrose exhaustion. These conditions allowed recovery of about 2.5 g/l aroma compounds after 230 h cultivation with a molar yield close to 100%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050394
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    A rapid bactometer method for screening of biocides against sulfate-reducing bacteria (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 336-340 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  A rapid and efficient bactometer method was developed for screening biocides against sulfate-reducing bacteria. The method is based on impedance microbiology principles and uses double-layer API (American Petroleum Institute) agar medium supplemented with 0.1% sodium thioglycolate as a reducing agent. Compared to the conventional API procedure, which requires 28 days, the present technique takes only 1 day to obtain test results. Excellent linear correlation (r=–0.98) was found between the impedance detection time and log initial cell concentration. The results of the bactometer test were comparable to that of the API bottle test.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050413
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    On-line measurement of dissolved and gaseous hydrogen sulphide in anaerobic biogas reactors (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 341-345 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The paper presented demonstrates the calibration of a silicone membrane probe for measurement of hydrogen sulphide in liquid and gas phase. The probe is connected to a quadrupole mass spectrometer as detector. The calibration of the probe results in linear calibration functions for different liquids and the gas phase. An example of the application of the measuring device for on-line measurement is reported for an experiment where sulphide is precipitated as iron sulphide by the addition of ferrous chloride. As a consequence of the addition of ferrous chloride, the concentration of H2S in the biogas rapidly decreases from 4.2% to 1.0% (by volume). The inhibition of the anaerobic treatment process is calculated on the basis of the reduction of dissolved total organic carbon before and during the experiment. The reduction of dissolved total organic carbon before the experiment starts is constant at 60%, rising to a maximum of 70% during the addition of FeCl2. The difference in the conversion rate corresponds to an inhibition of about 14%. The gas production increases from 7.5 l l–1 day–1 to 8.5 l l–1 day–1. This inhibition observed before the addition of FeCl2 is caused by 65  mg/l undissociated hydrogen sulphide in the liquid phase as calculated from the data obtained after precipitation of sulphide as zinc sulphide. The data show clearly that the conversion of acetic acid to methane is inhibited by dissolved H2S. The concentration of acetic acid drops sharply from about 25 mM to 15 mM after the FeCl2 dosage has been started. The concentration of propionic acid decreases slightly from 12 mM to 9  mM. Most of the iron introduced during the experiment is immediately precipitated. The maximum concentration of dissolved iron measured in the effluent is 93 mg/l.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050414
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Performance of a hybrid anaerobic reactor, combining a sludge blanket and a filter, treating slaughterhouse wastewater (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 351-357 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  A column reactor, in which the bottom two-thirds were occupied by a sludge blanket and the upper one-third by submerged clay rings, was evaluated using slaughterhouse wastewater as substrate. The reactor was operated at 35°  C at loading rates varying from 5 g to 45 g chemical oxygen demand (COD) l–1×day–1 at an influent concentration of 2450 mg COD l–1. A maximum substrate removal rate of 32 g COD l–1×day–1, coupled with a methane production rate of 6.9 l×l–1×day–1 (STP), was obtained. This removal rate is significantly higher than those previously reported. The rate of substrate utilization by the biomass was 1.22 g COD (g volatile suspended solids)–1 day–1. COD removal was over 96% with loading rates up to 25 g COD l–1×day–1, at higher loading rates performance decreased rapidly. It was found that the filter element of the reactor was highly efficient in retaining biomass, leading to a biomass accumulation yield coefficient of 0.029 g volatile suspended solids g–1 COD, higher than reported previously for either upflow anaerobic sludge-blanket reactors or anaerobic filters operating independently.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050416
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Use of activated carbon as a buffer in biofiltration of waste gases with fluctuating concentrations of toluene (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 365-369 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Fluctuations in contaminant concentrations often adversely influence the effectiveness of bioreactors for waste gas treatment. Application of an adsorbent to minimize such fluctuations could improve the overall process. Therefore the buffer capacity of a number of activated carbons and other adsorbents was tested. The buffer capacity of the adsorbents depends on the desired concentration range of the contaminants entering the bioreactor and on the time available for desorption. When fluctuations between 0 and 1000 mg toluene m–3 were applied to a biofilter this resulted in significant concentrations of toluene leaving the biofilter. Using one selected type of activated carbon it was demonstrated that these fluctuations could be decreased to a value of about 300 mg m–3, which was subsequently completely degraded in the biofilter.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050418
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Substrate availability in phenanthrene biodegradation: transfer mechanism and influence on metabolism (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 952-960 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The mechanism of phenanthrene transfer to the bacteria during biodegradation by a Pseudomonas strain was investigated using a sensitive respirometric technique (Sapromat equipment) allowing the quasi-continuous acquisition of data on oxygen consumption. Several systems of phenanthrene supply, crystalline solid and solutions in non-water-miscible solvents (silicone oil and 2,2,4,4,6,8,8-heptamethylnonane) were studied. In all cases, analysis of the kinetics of oxygen consumption demonstrated an initial phase of exponential growth with the same specific growth rate. In order to analyze the second phase of growth and phenanthrene degradation, a study of the kinetics of phenanthrene transfer to the aqueous phase was conducted by direct experimentation, with the crystal and silicone oil systems, in abiotic conditions. The data allowed the validation of a model based on phase-transfer laws, describing the variations, with substrate concentrations, of rates of phenanthrene transfer to the aqueous phase. Analysis of the biodegradation curves then showed that exponential growth ended in all cases when the rates of phenanthrene consumption reached the maximal transfer rates. Thereafter, the biodegradation rates closely obeyed, for all systems, the transfer rate values given by the model. These results unambiguously demonstrated that, in the present case, phenanthrene biodegradation required prior transfer to the aqueous phase. With the silicone oil system, which allowed high transfer and biodegradation rates, phenanthrene was directed towards higher metabolite production and lower mineralization, as shown by oxygen consumption and carbon balance determinations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050510
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Glycerol fermentation by a new 1,3-propanediol-producing microorganism:Enterobacter agglomerans (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 786-793 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract According to their ability to synthesize 1,3-propanediol from glycerol, two species were isolated from the anoxic mud of a distillery waste-water digestor:Clostridium butyricum andEnterobacter agglomerans. The latter, a facultatively anaerobic gram-negative bacterium, is described for the first time as a microorganism producing 1,3-propanediol from glycerol. The products of glycerol conversion byE. agglomerans were identified using nuclear magnetic resonance. A 20-g/l glycerol solution was fermented mainly to 1,3-propanediol (0.51 mol/mol) and acetate (0.18 mol/mol). Ethanol, formate, lactate and succinate were formed as by-products. Gas production was very low; 1,3-propanediol production perfectly balanced the oxido-reduction state of the microorganism. Acetate was the predominant metabolite generating energy for growth. High-glycerol-concentration fermentations (71 g/l and 100 g/l) resulted in an increase of the 1,3-propanediol yield (0.61 mol/mol) at the expense of lactate and ethamol production. Specific rates of glycerol consumption and 1,3-propanediol and acetate production increased whereas the growth rate decreased. The decreased in ATP yield was linearly correlated with the specific rate of 1,3-propanediol production. Incomplete glycerol consumption (about 40 g/l) was systematically observed when high glycerol concentrations were used. The unbalanced oxido-reduction state, the low carbon recovery and the detection of an unknown compound by HPLC observed in these cases indicate the formation of another metabolite, which is possibly an inhibitory factor.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02431909
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Relationship between molecular states (conformation and orientation) and activities of α-amylase adsorbed on ultrafine silica particles (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 801-807 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Bacillus subtilis α-amylase, which contains a relatively large amount of α-helix, was adsorbed on two types of ultrafine silica particles (silica-1 and-2, average diameter 15 nm) under various conditions. The changes in circular dichroism (CD) spectra of α-amylase upon adsorption were measured, and the extent of conformational changes was estimated from the reduction in α-helix content. In additions the activities of adsorbed α-amylase were measured at pH 5.2 using corn starch andp-nitrophenylbenzyl α-maltopentaoside (BG5P). In the ultrafine silica-2 particles, the extent of both activity reductions and conformational changes upon adsorption was much larger than that in the ultrafine silica-1 particles and increased with decreasing pH and amount of adsorption. The extent of activity reductions correlated closely with the conformational changes. On the other hand, the effect of reduction in α-amylase activity upon adsorption measured by BG5P was smaller than that measured by starch, indicating that the lack of accessibility of the active site to a large substrate also reduces the activity of adsorbed α-amylase. However, the effects of particle type and adsorption conditions on the extent of activity reductions by the accessibility resistance were small. Therefore, variation of the activity of adsorbed α-amylase is mainly attributable to the extent of conformational changes upon adsorption. Based on these results, a procedure to prepare adsorbed α-amylase with high activity was investigated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02431911
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Purification and properties of an alkaline protease from alkalophilic Bacillus sp. KSM-K16 (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 473-481 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Alkaline protease (EC 3.4.21.14) activity, suitable for use in detergents, was detected in the alkaline culture medium of Bacillus sp. KSM-K16, which was originally isolated from soil. The enzyme, designated M protease, was purified to homogeneity from the culture broth by column chromatographies. The N-terminal amino acid sequence was Ala-Gln-Ser-Val-Pro-Trp-Gly-Ile-Ser-Arg-Val-Gln-Ala-Pro-Ala-Ala-His-Asn-Arg-Gly-Leu-Thr-Gly. The molecular mass of the protease was 28 kDa, and its isoelectric point was close to pH 10.6. Maximum activity toward casein was observed at 55°C and at pH 12.3 in 50 mM phosphate/NaOH buffer. The activity was inhibited by phenylmethylsulfonyl flouride and chymostatin. The enzyme was very stable in long-term incubation with liquid detergents at 40°C. The enzyme cleaved the oxidized insulin B chain initially at Leu15-Tyr16 and efficiently at ten more sites. Among various oligopeptidyl p-nitro-anilides (pNA) tested, N-succinyl-Ala-Ala-Pro-Phe-pNA was efficiently hydrolyzed by M protease. M protease was precipitated in (NH4)2SO4-saturated acetate buffer (pH 5.0) as plank-like cyrstals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218452
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    A novel promoter, derived from the isocitrate lyase gene of Candida tropicalis, inducible with acetate in Saccharomyces cerevisiae (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 489-492 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract When the isocitrate lyase gene, containing 5'-upstream and 3'-flanking regions, of an n-alkane-assimilating yeast Candida tropicalis was introduced into Saccharomyces cerevisiae, the enzyme was functionally overexpressed in the cells grown on acetate. The amount of the recombinant isocitrate lyase expressed in S. cerevisiae was as much as 30% of the total soluble proteins in the cells, being comparable to that with GAL7 functional under the control of galactose. The expression was also observed when the cells were grown on glycerol, lactate, ethanol or oleate. These facts indicate that the isocitrate lyase gene upstream region (UPR-ICL) contains a strong promoter functional in S. cerevisiae. UPR-ICL is active as a promoter on cheap carbon sources such as acetate and nonconventional carbon sources such as oleate, whereas many conventional strong promoters demand relatively expensive sugars or sugars derivatives. Therefore, it is promising to construct an economical recombinant protein production system by using UPL-ICL.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218454
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Stable multicopy integration of vector sequences inHansenula polymorpha (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 844-849 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Plasmids without an origin of replication, but bearing theURA3 gene ofSaccharomyces cerevisiae as a selective marker for transformation, are shown to replicate autonomously inHansenula polymorpha, indicating that parts of theS. cerevisiae URA3 gene can fulfil an autonomous replication and stabilization function inH. polymorpha. Such plasmids, replicated in low copy number in monomeric conformation, could be rescued inE. coli, and showed a low mitotic stability under selective and non-selective conditions. Selective propagation of such transformants, however, led to the integration of plasmid sequences into theH. polymorpha genome. The integration event usually occurred in high copy number (approx. 30–50) at a single non-homologous site of the genome. The plasmid sequences were found to be present in tandem array and stable under non-selective conditions. It contrast, the use of homologousURA3 gene under similar conditions led to low-copy-number transformants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02431917
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Characterization of recombinantE. coli ATCC 11303 (pLOI 297) in the conversion of cellulose and xylose to ethanol (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 850-855 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract This work describes the characterization of recombinantEsherichia coli ATCC 11303 (pLOI 297) in the production of ethanol from cellulose and xylose. We have examined the fermentation of glucose and xylose, both individually and in mixtures, and the selectivity of ethanol production under various conditions of operation. Xylose metabolism was strongly inhibited by the presence of glucose. Ethanol was a strong inhibitor of both glucose and xylose fermentations; the maximum ethanol levels achieved at 37°C and 42°C were about 50 g/l and 25 g/l respectively. Simmultaneous sacharification and fermentation of cellulose with recombinantE. coli and exogenous cellulose showed a high ethanol yield (84% of theoretical) in the hydrolysis regime of pH 5.0 and 37°C. The selectivity of organic acid formation relative to that of ethanol increased at extreme levels of initial glucose concentration; production of succinic and acetic acids increased at low levels of glucose ( 〈1 g/l), and lactic acid production increased when initial glucose was higher than 100 g/l.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02431918
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Study of a single and mixed culture for the direct bio-conversion of sorghum carbohydrates to ethanol (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 412-415 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Fusarium oxysporum F3 alone or in mixed culture with Saccharomyces cerevisiae 2541 fermented soluble and insoluble carbohydrates of sweet sorghum stalk directly to ethanol. Both microorganisms were first grown aerobically and fermented sorghum stalk to ethanol thereafter. During fermentation, insoluble carbohydrates were hydrolysed to soluble sugars by the celluloytic system of F. oxysporum. Ethanol yields as high as 24.4 and 33.5 g/100 g dry stalks were obtained by F. oxysporum and the mixed culture respectively, representing a theoretical yield enhancement of 11.6% and 53.6% respectively. The corresponding ethanol concentrations in the fermentation medium were 4.6% and 6.4% (w/v). These results clearly demonstrated that a large portion of insoluble carbohydrate from sorghum was converted by simultaneous saccharification and fermentation to ethanol, making the process promising for bioethanol production.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050427
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Production of anthraquinones by immobilized Frangula alnus Mill. plant cells in a four-phase air-lift bioreactor (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 416-423 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The production of anthraquinones by Frangula alnus Mill. plant cells was used as a model system to evaluate the performance of a liquid-liquid extractive product-recovery process. The shake flask experiments have shown higher production of anthraquinones in cell suspension and flask cultures of calcium-alginate-immobilized cells when silicone oil was incorporated into the medium, compared to a control without silicone oil. An external-loop air-lift bioreactor, developed and designed for the production and simultaneous extraction of extracellular plant cell products, was regarded as a four-phase system, with dispersed gas, non-aqueous solvent and calcium-alginate-immobilized plant cells in Murashige and Skoog medium. Continuous extraction of anthraquinones by silicone oil and n-hexadecane inside the bioreactor resulted in 10–30 times higher cell productivity, compared to that of immobilized cells in a flask. Based on the mixing pattern, immobilized biocatalyst extraparticle and intraparticle diffusional constraints and the kinetics of growth, substrate consumption and product formation, a mathematical model was developed to describe the time course of a batch plant cell culture. The model showed satisfactory agreement with four sets of shake flask experiments and three bioreactor production cycles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050428
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Experimental and theoretical investigations of submerged fermentation and synthesis of pectinolytic enzymes by Aspergillus niger (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 424-430 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The growth of the microorganism and the production of the pectinolytic enzyme complex in a stirred 30-l biofermentor using the Aspergillus niger Rehbrücke strain were studied. The time courses of fermentation parameters (formation of biomass, consumption of carbon and inorganic nitrogen source, formation of pectinolytic enzymes) were measured. The formation of biomass showed a distinct lag phase, followed by a log phase with exponential growth and finally a stationary period when cell lysis was beginning. The uptake of the carbon source and inorganic nitrogen source by the A. niger cells corresponded to the time course of growth. The formation of pectinolytic enzymes took place in two steps. The first one was growth-bounded and finished with the end of the log phase of biomass growth. The second step of pectinolytic enzyme formation took place after the end of the catabolite repression of the carbon source and was not growth-bounded. On the basis of the experimental data a mathematical model of the fermentation process was developed. Comparison of the kinetics of the measured fermentation curves and the solution curves of the model showed qualitatively good agreement.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050429
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Relationships between molecular states (conformation and orientation) and activities of α-amylase adsorbed on ultrafine silica particles (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 801-807 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Bacillus subtilisα-amylase, which contains a relatively large amount of α-helix, was adsorbed on two types of ultrafine silica particles (silica-1 and -2, average diameter 15 nm) under various conditions. The changes in circular dichroism (CD) spectra of α-amylase upon adsorption were measured, and the extent of conformational changes was estimated from the reduction in α-helix content. In addition, the activities of adsorbed α-amylase were measured at pH 5.2 using corn starch and p-nitrophenylbenzyl α-maltopentaoside (BG5P). In the ultrafine silica-2 particles, the extent of both activity reductions and conformational changes upon adsorption was much larger than that in the ultrafine silica-1 particles and increased with decreasing pH and amount of adsorption. The extent of activity reductions correlated closely with the conformational changes. On the other hand, the effect of reduction in α-amylase activity upon adsorption measured by BG5P was smaller than that measured by starch, indicating that the lack of accessibility of the active site to a large substrate also reduces the activity of adsorbed α-amylase. However, the effects of particle type and adsorption conditions on the extent of activity reductions by the accessibility resistance were small. Therefore, variation of the activity of adsorbed α-amylase is mainly attributable to the extent of conformational changes upon adsorption. Based on these results, a procedure to prepare adsorbed α-amylase with high activity was investigated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050488
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Aldehyde production by alcohol oxidation with Gluconobacter oxydans (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 989-994 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The microbial oxidation of various primary alcohols to the corresponding aldehydes has been investigated. A focused screening performed amongst some acetic acid bacteria showed that a newly isolated strain of Gluconobacter oxydans oxodizes various short-chain aliphatic alcohols to the corresponding aldehydes with negligible acid production. 3-Methyl-1-butanol (isoamyl alcohol) proved to be the better substrate with high yields (more than 90%) without by-product formation. This biotransformation also occurs with continuous or semicontinuous addition of substrate since the volatile product is removed from the medium under vigorous aeration conditions. Product recovery is attained either by the use of cold traps or by reversible complex formation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166914
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Sulfur chemistry, biofilm, and the (in)direct attack mechanism — a critical evaluation of bacterial leaching (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 961-966 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract It has been shown (a) that bacterial leaching of metal sulfides apparently requires the attachment of leach bacteria to metal sulfides, (b) that exopolymerbound iron compounds are responsible for or at least considerably increase the rate of the biological attack over the chemical rate, (c) that the primary attacking agent in leaching environments is the ferric iron hexahydrate ion, (c) that thiosulfate is the first intermediate sulfur compound, giving rise to a variety of other compounds including polythionate-containing periplasmic granula, and (d) that we have no idea about the actual concentrations of protons, ferrous/ferric and/or other cations, and sulfur compounds in the reaction space between the bacterium and the sulfide surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166909
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Production of flavour esters by Rhizopus oryzae (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 967-973 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Microbial production of different alipathic esters with flavour characteristic has been studied. Lyophilized whole cells of Rhizopus oryzae CBS 112-07 were found to be particularly suitable to catalyse the synthesis of different flavour esters (hexyl acetate, propionate, butyrate, caprylate; geranyl acetate, propionate, butyrate and 2- and 3-methylbutyl acetate, butyrate) in n-heptane. This strain was therefore utilized for the semipreparative production of geranyl butyrate by semicontinous and continous addition of the substrates with satisfactory yields (144 g l−1 in 264 h and 142 g l−1 in 48 h respectively).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166910
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Optical resolution of racemic pantolactone with a novel fungal enzyme, lactonohydrolase (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 974-977 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A novel enzymatic process for the optical resolution of racemic pantolactone through the stereo-specific hydrolysis of d-pantolactone by lactonohydrolase of Fusarium oxysporum is described. F. oxysporum cells were found to catalyze the stereoselective hydrolysis of the d-enantiomer of racemic pantolactone. With 135 g/l dl-pantolactone as the substrate, 41% was hydrolyzed and pantoic acid with an optical purity of 90% enantiomeric excess (for d-pantoic acid) was formed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166911
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Microbial production of specifically ring-13C-labelled 4-hydroxybenzoic acid (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 985-988 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract When transformed with a recombinant vector carrying the ubiC gene (encoding chorismate pyruvate-lyase, EC 4.1.3.27) the triple mutant (Phe−, Trp−, Tyr−) Klebsiella pneumoniae 62-1 excretes 4-hydroxybenzoic acid instead of chorismic acid. The recombinant strain can be used to produce in high yield specifically ring-labelled 4-hydroxybenzoic acid from isotopically labelled glucose.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166913
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Isolation and characterization of exocellular polysaccharides produced by Bifidobacterium longum (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 995-1000 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract When grown anaerobically at pH values above 5.0, on ultrafiltered complex media containing excess lactose, Bifidobacterium longum formed up to 140 mg 1−1 (glucose equiv.) exopolysaccharides. The highest yield was obtained when the cells were cultivated in a peptone/yeast extract medium with pH controlled by additions of NH4OH. Whatever the conditions under study, exopolysaccharides represented about 30% of the polysaccharides produced by B. longum after 48 h of culture. Crude pronase-treated exopolysaccharide preparations were adsorbed on ion-exchange chromatographic resin to yield an anionic heteropolysaccharide fraction. Two subfractions with apparent molecular masses of 1.2 MDa and 0.36 MDa respectively were subsequently recovered after gel filtration on Sepharose 4B. In both subfractions, glucose, galactose and small amounts of uronic acids and hexosamines were present in similar molar proportions, suggesting that the excreted polymers may be synthesized from the same base unit and may have a structure resulting from repeating subunits.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166915
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Regulation of alcohol-oxidizing capacity in chemostat cultures of Acetobacter pasteurianus (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 1061-1066 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Acetobacter pasteurianus LMG 1635 was studied for its potential application in the enantioselective oxidation of alcohols. Batch cultivation led to accumulation of acetic acid and loss of viability. These problems did not occur in carbon-limited chemostat cultures (dilution rate = 0.05 h−1) grown on mineral medium supplemented with ethanol, L-lactate or acetate. Nevertheless, biomass yields were extremely low in comparison to values reported for other bacteria. Cells exhibited high oxidation rates with ethanol and racemic glycidol (2,3-epoxy-1-propanol). Ethanol- and glycidol-dependent oxygen-uptake capacities of ethanol-limited cultures were higher than those of cultures grown on lactate or acetate. On all three carbon sources, A. pasteurianus expressed NAD-dependent and dye-linked ethanol dehydrogenase activity. Glycidol oxidation was strictly dye-linked. In contrast to the NAD-dependent ethanol dehydrogenase, the activity of dye-linked alcohol dehydrogenase depended on the carbon source and was highest in ethanol-grown cells. Cell suspensions from chemostat cultures could be stored at 4°C for over 30 days without significant loss of ethanol- and glycidol-oxidizing activity. It is concluded that ethanol-limited cultivation provides an attractive system for production of A. pasteurianus biomass with a high and stable alcohol-oxidizing activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166926
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    DNA-mediated transformation of a fungus employing a vector devoid of bacterial DNA sequences (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 1077-1081 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Acremonium chrysogenum, a producer of cephalosporin C, was subjected to DNA-mediated transformaations using a vector without bacterial DNA sequences. Recombinant fungal strains were generated with a gel-purified DNA fragment, carrying only the mutated β-tubulin gene from A. chrysogenum. The lack of any bacterial DNA was verified by Southern hybridization analysis and polymerase chain reaction amplifications to detect even residual DNA sequences. This procedure can be referred to as a self-cloning experiment for which less restricted working regulations are needed. Finally, the transfer of a synthetic hirudin gene by contransformation demonstrated that any DNA molecule can be introduced into the A. chrysogenum genome without bacterial marker genes. This seems to be highly relevant for biotechnical processes in which safe recombinant producer strains are required to satisfy governmental restrictions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166928
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Evaluation of butanoic, pentanoic and hexanoic acids as internal standards for analysis of acidic fermentation end-products from Bacillus stearothermophilus by gas-liquid chromatography (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 626-631 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The use of butanoic, pentanoic and hexanoic acids as internal standards for chromatographic analysis of complex mixtures of by-products from acidic fermentation, produced by Bacillus stearothermophilus grown in xylose-containing medium, was evaluated. After addition of the internal standards, the aqueous supernatant microbial fermentation fluids were submitted to the derivatisation process with methanol and sulphuric acid at 50°  C. Injection of 1-μl aliquots of the lower chloroform layer was carried out. The esterified compounds were separated in approximately 14 min by temperature programming on a glass column packed with 10% (w/w) diethyleneglycol adipate and 2% phosphoric acid, and analysed with a flame ionisation detector. Chromatograms of the methyl esters derivates have shown that both pentanoic and hexanoic acids can be used as internal standards for gas-chromatographic analysis of acidic fermentation end-products, since they are well separated and resolved. Under the experimental conditions established, the methyl ester of butanoic acid was masked by the chloroform peak and so is not a convenient compound for further use.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164765
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Production of alginate beads by emulsification/internal gelation. II. Physicochemistry (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 644-650 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Alginate microspheres were produced by emulsification/internal gelation of alginate sol dispersed within vegetable oil. Gelification was initiated within the alginate sol by a reduction in pH (7.5 to 6.5), releasing calcium from an insoluble complex. Smooth, spherical beads with the narrowest size dispersion were obtained when using low-guluronic-acid and low-viscosity alginate and a carbonate complex as the calcium vector. A more finely dispersed form of the complexed calcium within the alginate sol promotes a more homogeneous gelification. Microsphere mean diameters ranging from 50 μm to 1000 μm were obtained with standard deviations ranging from 35% to 45% of the mean.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164768
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Electrotransformation of three pathovars of Xanthomonas campestris (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 651-655 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Procedures for electrotransformation have been adapted for three pathovars of Xanthomonas campestris: campestris, vesicatoria and manihotis. Three differently sized plasmids (51, 9.3 and 3.3 kb) at different concentrations (10, 30 and 50 ng/sample) and different field strengths (10, 12, 14 and 18 kV/cm) were used. The efficiency of transformation was dependent on the recipient strain and the plasmid introduced. In general, a field strength of 14 kV/cm as well as a concentration of 30 ng plasmid DNA/sample seemed to be adequate for most conditions. Only X. campestris pv. vesicatoria strain 479 required a higher field strength for better efficiency. The plasmid size was inversely related to the efficiency of transformation; up to 1.6×1010, 5.3×107 and 3.7×105 transformants/μg DNA were obtained using the pXG31 (3.3 kb), pUFR027 (9.3 kb) and RP4 (51 kb) plasmids, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164769
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Roles of alcohol dehydrogenases of Zymomonas mobilis (ZADH): characterization of a ZADH-2-negative mutant (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 675-678 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Zymomonas mobilis is a potential candidate for fuel ethanol production because of its high ethanol productivity. A key enzyme in ethanol production is alcohol dehydrogenase (ADH). Z. mobilis possesses two isozymes, ZADH-1 and ZADH-2. To clarify their physiological roles, mutants with modified ADH were isolated by selection based on resistance to allyl alcohol. From the physiological characteristics of a ZADH-2-negative mutant, it is suggested that ZADH-1 functions as the major ADH, while ZADH-2 could become functional in the latter stages of fermentation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164772
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Improvement of the catalytic properties of penicillin G acylase from Escherichia coli ATCC 11105 by selection of a new substrate specificity (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 679-684 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Cloned penicillin G acylase (PGA) from Escherichia coli ATCC 11105 was mutagenized in vivo using N–methyl-N′-nitro-N–nitrosoguanidine. Mutants of PGA were selected by their ability to allow growth of the host strain E. coli M8820 with the new substrates phenylacetyl-β-alanyl-L-proline (PhAc-βAla-Pro) phthalyl-L-leucine (Pht-Leu) or phthalylglycyl-L-proline (Pht-Gly-Pro) as sole source of proline and leucine respectively. PGA mutants were purified and immobilized onto spherical methacrylate (G-gel). The immobilized form of mutant PGA selected with (PhAc-βAla-Pro) hydrolyzed 95% of 9 mmol penicillin G 30% faster than wild-type PGA using the same specific activities. The specific activity of the soluble enzyme was 2.7-fold, and inhibition by phenylacetic acid was halved. Immobilized PGA mutant selected with Pht-Gly-Pro hydrolyzed penicillin G 20% faster than wild-type PGA. The K m of the soluble enzyme was increased 1.7-fold. Furthermore, the latter two mutants were also 3.6-fold more stable at 45°  C than wild-type PGA. The specific activity of the mutant selected with Pht-Leu was 6.3-fold lower, and inhibition by phenylacetic acid was increased 13-fold.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164773
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Regulation of scytophycin accumulation in cultures of Scytonema ocellatum II. Nutrient requirements (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 692-700 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The effects of optimal sources and concentrations of major nutrients (supplying N, S, P, K+, Na+, Ca2+, Mg2+, and inorganic carbon) and organic buffers on growth and secondary metabolite accumulation in Scytonema ocellatum strain FF-66-3 were determined. Nitrate, phosphate, magnesium, and sulfur had no specific stimulatory or inhibitory effects on scytophycin accumulation within the range of concentrations that supported optimal growth. Calcium concentrations greater than those required for growth (0.1 mM) stimulated scytophycin accumulation. Sodium carbonate concentrations in excess of 0.25 mM strongly inhibited growth. Ammonium (2.5 mM) inhibited both growth and product formation. 3-[N-Morpholino]propanesulfonic acid at 3–5 mM effectively controlled pH and facilitated both growth and product formation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164775
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Negative effect of ammonium nitrate as nitrogen source on the production of water-soluble red pigments by Monascus sp. (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 701-705 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Ammonium salts, especially ammonium nitrate, have been used as nitrogen sources for production of traditional water-insoluble Monascus pigments. However, we noted that defined media employing NH4NO3 as the sole nitrogen source in fermentations supported only poor pigment production by Monascus sp., and the pigments produced were mainly cell-bound. NH4NO3 was found not to (a) repress pigment synthase formation, (b) enhance synthase decay, or (c) serve as a nitrogen source for pigment production by resting cells; it had a weak inhibitory effect on the action of pigment synthase(s). The high level of cell-bound pigments accumulated in NH4NO3-grown cells did not exert a feedback effect on the further synthesis of pigments. These observations indicate that the reason why NH4NO3 supports only low pigment production during fermentations is the poor ability of NH4NO3 to donate nitrogen in the Schiff-base reaction converting orange pigments to red ones.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164776
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Evidence for a membrane-bound pyrroloquinoline quinone-linked glucose dehydrogenase in Acetobacter diazotrophicus (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 713-716 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Acetobacter diazotrophicus possesses a pyrroloquinoline quinone-linked glucose dehydrogenase (PQQ-GDH). The enzyme seemingly belongs to the type II PQQ-GDH enzymes and, at least under the culture conditions tested, the organism synthesizes enough PQQ to saturate the apo-enzyme. The synthesis of this enzyme is stimulated when the organism is grown under N2-fixing conditions. It is proposed that this enzyme may play an important role in providing extra energy in N2-fixing cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164778
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Ultrastructural aspects of wheat straw degradation by Phanerochaete chrysosporium and Trametes versicolor (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 766-770 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The ultrastructural patterns characterizing wheat straw degradation by the ligninolytic fungi Phanerochaete chrysosporium and Trametes versicolor were studied. During fungal attack, the less lignified tissues were degraded first, whereas the xylematic and sclerenchymatic fibers underwent a delayed attack. In straw samples degraded by T. versicolor, partial delignification, defibrillation and swelling of cell walls, often causing separation between primary and secondary walls, were observed. By contrast, the formation of erosions and fissures, with minor lignin removal, characterized the attack to the cell wall by P. chrysosporium. At an advanced stage of decay, KMnO4 staining demonstrated abundant electron-dense material around hyphae and in the proximity of the cell-wall surface. In the case of P. chrysosporium, spherical black bodies were found in the erosions and fissures produced during fungal attack.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164786
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Bioremediation of selenite in oil refinery wastewater (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 762-765 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Selenium-oxyanion-containing wastewater, with levels of selenite as high as 3690 μg Se/l and very low levels of selenate, was treated in a laboratory-scale biological reactor system inoculated with the selenate-respiring bacterium Thauera selenatis. The wastewater contained selenite that had been removed from refinery effluent wastewater using iron-coprecipitation followed by selenite release to yield a more concentrated selenium-containing wastewater. The reactor system consisted of recycling sludge-blanket (500 ml; 200 g sand) and fluidized-bed reactors (500 ml; 150 g sand). The flow rate through the reactor system was 3.5 ml/min. The carbon source fed into the reactor was acetate (3 mM); nitrate was also present (3 mM). The selenium oxyanion levels in the wastewater were reduced by 95%. T. selenatis was the only selenate-reducing bacterium detected in the reactor system and it presumably reduced a portion of the selenate present in the water to selenite. The selenite present in the water, and that formed by selenate reduction, was reduced both by the Thauera and by a population of denitrifying bacteria also present in high numbers in the reactor system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164785
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Permeabilization and lysis of Pseudomonas pseudoalcaligenes cells by Triton X-100 for efficient production of d-malate (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 590-594 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Pseudomonas pseudoalcaligenes can only form d-malate from maleate after incubation of the cells with a solvent or a detergent. The effect of the detergent Triton X-100 on d-malate production was studied in more detail. The longer the cells were incubated with Triton X-100, the higher was the d-malate production activity, until the maximal malease activity was reached. Incubation of P. pseudoalcaligenes cells with Triton X-100 also resulted in an increase in the protein concentration of the supernatant, indicating that cell lysis had occurred. The rate at which the d-malate production activity increased was dependent on the Triton X-100 concentration and on the cell density. Also the rate at which lysis occurred depended on the Triton X-100 concentration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164759
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Enhanced production of pigment-free pullulan by a morphogenetically arrested Aureobasidium pullulans (ATCC 42023) in a two-stage fermentation with shift from soy bean oil to sucrose (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 595-603 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A two-stage fermentation process was established for the production of pigment-free pullulan by the yeast-like fungus Aureobasidium pullulans (ATCC 42023). In the first stage, starting at pH 4.5 with soy bean oil as the carbon source and glutamate as the nitrogen source, a cell mass of about 15 g l−1 dry cell weight was obtained, the population being restricted mainly to the yeast form of the microorganism (yeast form more than 90% of total cells) and the formation of pigment in the culture being prevented. Small amounts of pullulan (less than 2 g l−1) are produced at this phase, and the viscosity remained low throughout the entire growth stage. When the oil and glutamate source were nearly exhausted (below 5% of initial amounts), the cells were shifted to a production stage with sucrose as the carbon source with continued nitrogen depletion. Production of pullulan started immediately with no lag period. During 50 h of the production phase more than 35 g l−1 of pullulan was produced (productivity approx. 0.7 g l−1), resulting in a large increase in the viscosity of the broth. The production yield of pollulan on the sugar was about 0.6 g g−1. Morphogenesis from the yeast form of the microorganism to chlamydospores was still restrained and no pigment was formed in the culture during the production stage. A pigment-free polysaccharide, with a molecular mass in the range of 600–750 kDa, was recovered from the supernatant of the broth after solvent precipitation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164760
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Cellulase induction by lactose in Trichoderma reesei PC-3-7 (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 106-111 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  In an attempt to clarify the function of lactose in cellulase induction, experiments were carried out on cellulase formation by lactose along with other sugars in a resting cell system of Trichoderma reesei PC-3-7, a hypercellulase-producing mutant. Although lactose alone induces little cellulase under the conditions used, a synergistic effect on cellulase formation was observed following the respective addition of sophorose, cellobiose or galactose to lactose. The lactose consumption was more rapid when these sugars were added than in their absence. Furthermore, following lactose addition 10 h after the beginning of cultivation in the presence of cellobiose, cellulase formation was initiated with only a little lag, and lactose consumption started immediately, being complete in 14 h. β-Galactosidase induction experiments suggested that the rapid consumption of lactose is possibly not dependent on lactose degradation by the enzyme. From these results, it is suggested that lactose may function as an inducer for cellulase formation if it is taken up in the mycelium of T. reesei PC-3-7, and that sophorose, cellobiose or galactose may induce a putative lactose permease.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050527
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    In vitro electrochemical detection of wheat allergen using rat basophilic leukaemia (RBL-1) cells (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 622-625 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract We have investigated an electrochemical method of detecting foods that cause an allergic reaction. Rat basophilic leukaemia (RBL-1) cells were sensitized with serum from a rat that was allergic to wheat. A sample containing the protein fraction of a food was added to the cells and incubated. The cells were immobilized on a membrane filter and attached to a basalplane pyrolytic graphite electrode. When a potential was applied in the range 0–1.0 V relative to a saturated calomel electrode, an anodic peak current appeared at around 0.33 V. This peak current, attributed to serotonin, increased with time, and the maximum current (0.5 μA) was obtained 20–25 min of incubation. The response of the RBL-1 cells was specific to the protein fraction of wheat. The peak current increased linearly with increasing protein concentration in the range of 0.01–0.5 μg ml−1. These results suggest that the concentration of the protein bringing about the allergic reaction can be determined by cyclic voltammetry within 25 min. This method is more sensitive than the conventional skin tests.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164764
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Biosynthesis of poly(3-hydroxybutyrate-Co-3-hydroxyvalerate) by a mutant of Sphaerotilus natans (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 37-42 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The copolyester of 3-hydroxybutyrate and 3- hydroxyvalerate was synthesized from the combined carbon sources of glucose and sodium propionate by a filamentaion-defective mutant of Sphaerotilus natans, which is a typical filamentous bacterium often found in activated sludge. The 3-hydroxyvalerate content in the produced polymer increased with increasing concentrations of propionate. Cell growth and polyester synthesis were observed even when 0.6% sodium propionate was added to the medium, when the 3-hydroxyvalerate content in the polymer produced was about 60 mol%. The monomer composition of the copolymer was also varied by aeration conditions, time of propionate feeding, and cultivation time. This strain flocculated in accordance with cell growth, allowing rapid and convenient separation of the biomass from the culture fluid.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164477
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    CMP-N-acetyl neuraminic-acid synthetase from Escherichia coli: fermentative production and application for the preparative synthesis of CMP-neuraminic acid (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 59-67 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract In an optimized sorbitol/yeast extract/mineral salt medium up to 12 U/l CMP-N-acetyl-neuraminic-acid (Neu5Ac) synthetase was produced by Escherichia coli K-235 in shake-flask culture. A colony mutant of this strain, E. coli K-235/CS1, was isolated with improved enzyme formation: in shake flasks with a yield of up to 20.8 U/l and 54 mU/mg protein in the cell extract. With this strain 26500 U CMP-Neu5Ac synthetase was produced with a high specific activity (0.128 U/mg) by fed-batch fermentation on 230-1 scale. On a 10-l scale the enzyme yield was 191 U/l culture medium. The enzyme was partially purified by precipitation with polyethyleneglycol resulting in a three- to fourfold enrichment and a recovery rate of more than 80%; most of the CTP hydrolysing enzymes were removed. The native synthetase was deactivated completely by incubation at 45°C for 10 min, but could be stabilized remarkably by glycerol and different salts. The enzyme was used for the preparative synthesis of CMP-Neu5Ac with a conversion yield of 87% based on CTP.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164481
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Direct isolation of functional genes encoding cellulases from the microbial consortia in a thermophilic, anaerobic digester maintained on lignocellulose (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 667-674 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Gene libraries (“zoolibraries”) were constructed in Escherichia coli using DNA isolated from the mixed liquor of thermophilic, anaerobic digesters, which were in continuous operation with lignocellulosic feedstocks for over 10 years. Clones expressing cellulase and xylosidase were readily recovered from these libraries. Four clones that hydrolyzed carboxymethylcellulose and methylumbelliferyl-β-d-cellobiopyranoside were characterized. All four cellulases exhibited temperature optima (60–65° C) and pH optima (pH 6–7) in accordance with conditions of the enrichment. The DNA sequence of the insert in one clone (plasmid pFGH1) was determined. This plasmid encoded an endoglucanase (celA) and part of a putative β-glucosidase (celB), both of which were distinctly different from all previously reported homologues. CelA protein shared limited homology with members of the A3 subfamily of cellulases, being similar to endoglucanase C from Clostridium thermocellum (40% identity). The N-terminal part of CelB protein was most similar to β-glucosidase from Pseudomonas fluorescens subsp. cellulosa (28% homology). The use of zoolibraries constructed from natural or laboratory enrichment cultures offers the potential to discover many new enzymes for biotechnological applications.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164771
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Roles of alcohol dehydrogenases of Zymomonas mobilis (ZADH): characterization of a ZADH-2-negative mutant (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 675-678 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Zymomonas mobilis is a potential candidate for fuel ethanol production because of its high ethanol productivity. A key enzyme in ethanol production is alcohol dehydrogenase (ADH). Z. mobilis possesses two isozymes, ZADH-1 and ZADH-2. To clarify their physiological roles, mutants with modified ADH were isolated by selection based on resistance to allyl alcohol. From the physiological characteristics of a ZADH-2-negative mutant, it is suggested that ZADH-1 functions as the major ADH, while ZADH-2 could become functional in the latter stages of fermentation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164772
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Regulation of scytophycin accumulation in cultures of Scytonema ocellatum. II. Nutrient requirements (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 692-700 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The effects of optimal sources and concentrations of major nutrients (supplying N, S, P, K+, Na+, Ca2+, Mg2+, and inorganic carbon) and organic buffers on growth and secondary metabolite accumulation in Scytonema ocellatum strain FF-66-3 were determined. Nitrate, phosphate, magnesium, and sulfur had no specific stimulatory or inhibitory effects on scytophycin accumulation within the range of concentrations that supported optimal growth. Calcium concentrations greater than those required for growth (0.1 mM) stimulated scytophycin accumulation. Sodium carbonate concentrations in excess of 0.25 mM strongly inhibited growth. Ammonium (2.5 mM) inhibited both growth and product formation. 3-[N-Morpholino]propanesulfonic acid at 3–5 mM effectively controlled pH and facilitated both growth and product formation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164775
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Preparation of enantiomerically pure (R)-(1-hydroxyethyl)dimethyl(phenyl)silane using resting cells of Saccharomyces cerevisiae (DHW S-3) as biocatalyst (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 671-674 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The prochiral sila-ketone acetyldimethyl-(phenyl)silane (1) was reduced enantioselectively into (R)-(1-hydroxyethyl)dimethyl(phenyl)silane [(R)-2] using resting cells of the commercially available yeast Saccharomyces cerevisiae (DHW S-3) as the biocatalyst. The bioconversion was performed on a 2.0-g scale in a 5-1 bioreactor. Starting with a substrate (1) concentration of 0.4 g·1−1, the highest production rate measured for this bioconversion was about 45–55 μmol (R)-2·1−1·min−1. After an incubation time of 1 h, all substrate in the medium had been converted, either biocatalytically reduced to (R)-2 or (probably chemically) converted into dimethyl(phenyl)silanol (Me2PhSiOH). After extraction of the cell-free medium with ethyl acetate/dichloromethane and subsequent purification of the extract by Kugelrohr distillation and chromatography on silica gel (medium-pressure liquid chromatography), 800 mg (yield 40%) of the bioconversion product (R)-2 was isolated. As shown by HPLC studies (cellulose triacetate as the chiral stationary phase) and 1H-nuclear magnetic resonance experiments (after derivatization of the bioconversion product with a chiral auxiliary agent), compound (R)-2 was almost enantiomerically pure (〉 99% enantiomeric excess).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00171942
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Cloning of FAD synthetase gene from Corynebacterium ammoniagenes and its application to FAD and FMN production (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 724-729 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The cloning of a bifunctional FAD synthetase gene, which shows flavokinase and FMN adenylyltrans- ferase activities, from Corynebacterium ammoniagenes was tried by hybridization with synthetic DNAs corresponding to the N-terminal amino acid sequence. The cloned PstI-digested 4.4×103-base (4.4-kb) fragment could not express the FAD synthetase activity in E. coli, but could increase the two activities by the same factor of about 20 in C. ammoniagenes. The FAD-synthetase-gene-amplified C. ammoniagenes cells were applied to the production of FAD from FMN or riboflavin. The productivity of FAD from FMN was increased four to five times compared with the parent strain, and reached a 90% molar yield. The productivity of FAD from riboflavin was increased about eight times, with a 50% molar yield. The addition of Zn2+ to the reaction mixtures for the conversion from riboflavin to FAD brought about the specific inhibition of adenylyltransferase activity and resulted in the accumulation of FMN.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050321
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Improvement of S-adenosylmethionine production by integration of the ethionine-resistance gene into chromosomes of the yeast Saccharomyces cerevisiae (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 730-733 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  An ethionine-resistance gene cloned from Saccharomyces cerevisiae DKD-5D-H was able to enhance S-adenosyl-L-methionine (AdoMet) accumulation when it was introduced into the yeast cells on multi-copy plasmid YEp13. In order to increase the AdoMet accumulation, the gene was integrated into the yeast chromosome by using a yeast transposon Ty element. When the YEp plasmid was used for the integration, the ethionine-resistance gene was efficiently inserted into the yeast chromosomes with a substantial increase in AdoMet productivity (about twofold) in comparison with that by the yeast cells carrying the gene on an extrachromosomal multi-copy plasmid.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050322
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Generation of a stable non-reverting Leu- mutant of Kluyveromyces lactis by gene disruption (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 734-737 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The LEU2 gene coding for β-isopropylmalate dehydrogenase of the yeast Kluyveromyces lactis strain AWJ137 was disrupted. In the resulting Leu- strain a 0.57×103-base pairs PstI/BglII fragment of the LEU2 coding region was replaced by the TRP1 gene of Saccharomyces cerevisiae. The mutant strain was characterized by stability tests and a physical map of the disrupted region was established by restriction-enzyme analysis combined with hybridization experiments. The usefulness of the mutant strain as a recipient was shown by transformation experiments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050323
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Selective biosorption of thorium ions by an immobilized mycobacterial biomass (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 271-276 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The biosorption of thorium and uranyl ions by cells of Mycobacterium smeamatis has been studied as a function of initial cation concentration. A similar sorption saturation level was observed for both ions. For immobilized cells, optimal conditions of metal ion retention were found for a bacterial mass/support concentration ratio of 1/6. However, selective uptake of thorium was manifest in solutions of the mixed cations. X-ray diffraction studies of the heat-dried biomasses loaded with cations showed that uranyl-loaded samples present a distinct pattern typical of ammonium uranyl phosphate, whereas thorium-loaded samples are amorphous. The microorganism used appears to have useful properties for applications in connection with separation and concentration of natural radioelements under conditions of high dilution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00164514
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Optimization of methyl propionate production catalysed by Mucor miehei lipase (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 321-326 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Lipase from Mucor miehei was used to catalyse the esterification reaction between propionic acid and methyl alcohol in modified organic media. Small-scale model studies were performed in order to define the optimal conditions. The specific activity of immobilized lipase, adsorbed onto hydrophilic supports, compared to free lipase, showed that enzyme activity was altered by immobilisation. Non-polar solvents were shown to be less harmful for the biocatalyst than solvents with higher polarity. Diethyl ether was used as the cosolvent of hexane to improve the solubility of substrates in the organic phase thus increasing contact with the enzyme. An optimal ratio of 90/10 (v/v) was determined for a hexane/diethyl ether mixture. The mass of enzyme preparation must be high enough to display optimal diffusion of the reagents and hydration of the catalytic sites. Increased substrate concentrations were stimulatory up to a point after which inhibition and enzyme destabilisation, in repeated runs, occurred. Water saturation of the organic medium greatly lowered the biosynthetic activity of the enzyme. It was possible to reach a 96% methyl propionate biosynthesis yield after 2.30 h reaction, underlining the free-enzyme operational capacity in a quasi-anhydrous modified organic medium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050561
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Growth substrates control the ability of Fusarium oxysporum to solubilize low-rank coal (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 351-355 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The ability of the fungus Fusarium oxysporum to solubilize lignite was found to depend on the presence of a specific carbon source. When grown on glucose or another carbohydrate, the fungus is unable to solubilize coal but it produces the red dye bikaverin. In the coal-solubilizing state, which can be induced by cultivation in the presence of glutamate or gluconate, the fungus does not produce bikaverin. The presence or absence of the pigment can therefore be taken as an indicator of the ability of the fungus to solubilize coal. Addition of extracted and purified bikaverin to F. oxysporum growing on glutamate or gluconate inhibits coal solubilization. Hence, F. oxysporum offers a suitable system for investigating the mechanisms of microbial coal degradation by comparing the two growth-substrate-controlled physiological states.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050566
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Utilization of chlorinated s-triazines by a new strain of Klebsiella pneumoniae (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 763-768 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  A bacterium utilizing 2-chloro-4, 6-diamino-s-triazine (CAAT) as sole nitrogen source was isolated under a N2-free atmosphere and identified as Klebsiella pneumoniae. Concomitant to CAAT degradation the protein content increased and chloride was released into the medium. Under air and a N2-atmosphere no reduction of CAAT degradation resulted, though this strain is able to fix molecular nitrogen, but the decomposition accelerated under anaerobic conditions. The degradation rate increased continuously with increasing CAAT concentration. A continuous CAAT degradation without CAAT accumulation was possible up to a influx rate of 4.8 μmol ⋅ l-1h-1 (dilution rate=0.007 h-1). K. pneumoniae A2 was also able to utilize deethylsimazine (CEAT) and deethylatrazine (CIAT) as nitrogen source. Both under aerobic and anaerobic conditions CEAT could be degraded faster than CIAT. The degradation sequence of mixed s-triazines was cyanuric acid〈CAAT〈CEAT〈CIAT, which was reflected by the degradation times of single compounds. Complete degradation was assumed for all investigated s-triazine derivatives.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050328
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Biotechnological management of coffee pulp - isolation, screening, characterization, selection of caffeine-degrading fungi and natural microflora present in coffee pulp and husk (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 756-762 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A total of 272 strains of filamentous fungi were isolated from soil, leaves of coffee plants and coffee cherries collected in coffee-growing areas of Mexico on three semi-synthetic culture media containing coffee extract, coffee extract with sucrose and coffee pulp extract. The isolated strains were purified by conventional techniques and identified by microscopic examination. Strains were selected on the basis of their caffeine-degrading ability in well-defined liquid medium containing caffeine. Most of the isolated microorganisms belong to Aspergillus, Penicillium, Trichoderma, Fusarium, and Humicola genera. Five strains belonging to Aspergillus species and two strains belonging to Penicillium species had the ability to degrade almost 100% of the caffeine in liquid medium. A comparative study on the evaluation of natural microflora present in coffee pulp and coffee husk revealed the presence of a wide variety of microorganisms. The percentage distribution of fungi, bacteria and yeast was almost similar in all the samples, except in coffee husk where the fungal population was slightly higher than in the other two samples. The yeast population was predominant when the coffee pulp was lyophilized immediately after pulping. However, there was a wide diversity in the microbial population with respect to selective media containing functional nutritional groups like cellulose, starch and pectin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050327
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Growth of an aerobic bacterium with trichloroacetic acid as the sole source of energy and carbon (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 769-774 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The aerobic microbial decomposition of trichloroacetic acid (TCA) was studied. A TCA-decomposing culture was enriched in continuous-flow and batch experiments on a medium containing TCA as the only organic component. Pure cultures of TCA degraders were isolated from the enrichment on TCA agar plates. Characterization of several isolates proved them all to be representatives of the same bacterium, a Gram-negative, catalase-positive and cytochrome C-oxidase-positive, non-motile, somewhat irregular rod. The bacterium could not be identified on the basis of its carbon-source-utilization pattern, but a partial sequencing of the 16S rDNA gene showed the isolate to belong to the gamma sub-group of Proteobacteria, and to be phylogenetically close to Acinetobacter calcoaceticus. The isolated bacterium grew exponentially with TCA as the sole source of energy and carbon. The maximum growth rate (μmax) and the growth yield on TCA (Y X / S ) were determined to be 0.027 h-1 and 0.027 g biomass/g TCA, respectively. The bacterium was not able to grow on mono- or dichloroacetic acid, but it could grow on acetate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050329
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Secretory overproduction of Arthrobacter simplex 3-ketosteroid Δ1-dehydrogenase by Streptomyces lividans with a multi-copy shuttle vector (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 1044-1049 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The gene for 3-ketosteroid Δ1-dehydrogenase (ksdD) of Arthrobacter simplex was expressed in Streptomyces lividans and the secreted enzyme was overproduced by using a multi-copy shuttle vector composed of pIJ702 and pUC19. Deletional analysis of the recombinant plasmid showed that the entire coding sequence of the ksdD gene was located within a 7-kb segment of the chromosomal DNA obtained from the enzyme-producing strain of A. simplex. When S. lividans carrying the recombinant plasmid was grown in an appropriate medium, the cells produced about 100-fold more 3-ketosteroid Δ1-dehydrogenase than the original strain. Although the percentage of enzyme secreted was changed during cultivation, a maximum 55% of the enzyme was secreted into the cultured medium of S. lividans, while A. simplex did not produce the enzyme extracellularly. Secretory overproduction of 3-ketosteroid Δ1-dehydrogenase in S. lividans was also identified by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and on native gel, and the enzyme reaction was confirmed by reverse-phase HPLC using 4-androstene-3,17-dione as a substrate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166923
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    A comparison of organochlorine removal from bleached kraft pulp and paper-mill effluents by dehalogenating Pseudomonas, Ancylobacter and Methylobacterium strains (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 782-789 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The relative importance of each of three dechlorinating species to overall organochlorine removal from bleached kraft-mill effluents (BKME) was assessed. Ancylobacter aquaticus A7, Pseudomonas P1, and Methylobacterium CP13, strains indigenous to a BKME treatment system, were tested for growth on chlorinated acetic acids and alcohols, and for adsorbable organic halogen (AOX) reduction in batch cultures of sterile BKME from three sources. A. aquaticus A7 exhibited the broadest substrate range, but could only affect significant AOX reduction in softwood effluents. Methylobacterium CP13 exhibited a limited substrate range, but was capable of removing significant amounts of AOX from both hardwood and softwood effluents. By contrast, Pseudomonas sp. P1 exhibited a limited substrate range and poor to negligible reductions in AOX levels from both effluent types. Mixed inocula of all three species combined and inocula of sludge from mill treatment systems removed as much AOX from softwood effluents as did pure populations of Methylobacterium CP13. When BKME was hydrolysed prior to AOX analysis, the subsequent estimates of recalcitrant, or non-hydrolysable, AOX levels were far less variable than their counterpart total AOX measures. It is suggested that this is a relevant and useful measure of AOX for biodegradation studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050331
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Cellobiose dehydrogenase (cellobiose oxidase) from Phanerochaete chrysosporium as a wood-degrading enzyme. Studies on cellulose, xylan and synthetic lignin (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 790-796 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Degradation of carboxymethylcellulose (CMC), xylan and synthetic lignin was studied in a cellobiose dehydrogenase system, that reduced Fe(III) to Fe(II) with cellobiose as electron donor, which in the presence of hydrogen peroxide degraded all the above representatives of the main wood components, probably by forming Fenton’s reagent. The production of hydroxyl radicals was shown by benzoate decarboxylation. For the CMC and xylan studies viscometry was used, while lignin degradation was studied by measuring the passage of 14C-labelled synthetic lignin (DHP) through membranes of different molecular-mass cut-off. The possible participation of cellobiose dehydrogenase, Fe(III) and hydrogen peroxide in wood degradation by white-rot and brown-rot fungi is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050332
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Biosorption of heavy metals by Saccharomyces cerevisiae (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 797-806 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Abundant and common yeast biomass has been examined for its capacity to sequester heavy metals from dilute aqueous solutions. Live and non-living biomass of Saccharomyces cerevisiae differs in the uptake of uranium, zinc and copper at the optimum pH 4–5. Culture growth conditions can influence the biosorbent metal uptake capacity which normally was: living and non-living brewer’s yeast: U〉Zn〉Cd〉Cu; non-living baker’s yeast: Zn〉(Cd)〉U〉Cu; living baker’s yeast: Zn〉Cu≈(Cd)〉U. Non-living brewer’s yeast biomass accumulated 0.58 mmol U/g. The best biosorbent of zinc was non-living baker’s yeast (≈0.56 mmol Zn/g). Dead cells of S. cerevisiae removed approximately 40% more uranium or zinc than the corresponding live cultures. Biosorption of uranium by S. cerevisiae was a rapid process reaching 60% of the final uptake value within the first 15 min of contact. Its deposition differing from that of other heavy metals more associated with the cell wall, uranium was deposited as fine needle-like crystals both on the inside and outside of the S. cerevisiae cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050333
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Studies on the biosorption of uranium by Talaromyces emersonii CBS 814.70 biomass (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 807-811 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Residual biomass, produced by the thermophilic fungus, Talaromyces emersonii CBS 814.70, following growth on glucose-containing media, was examined for its ability to take up uranium from aqueous solution. It was found that the biomass had a relatively high observed biosorption capacity for the uranium (280 mg/g dry weight biomass). The calculated maximum biosorption capacity obtained by fitting the data to a Langmuir model was calculated to be 323 mg uranium/g dry weight biomass. Pretreatment of the biomass with either dilute HCl or NaOH brought about a significant decrease in biosorptive capacity for uranium. Studies on the effects of variation in temperature on the biosorptive capacity demonstrated no significant change in binding between 20°C and 60°C. However, a significant decrease in biosorptive capacity was observed at 5°C. Binding of uranium to the bio mass at all temperatures reached equilibrium within 2 min. While the routine binding assays were performed at pH 5.0, adjustment of the pH to 3.0 gave rise to a significant decrease in biosorption capacity by the biomass. The biosorptive capacity of the biomass for uranium was increased when extraction from solution in sea-water was examined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050334
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Escherichia coli K12 relA strains as safe hosts for expression of recombinant DNA (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 718-723 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Most Escherichia coli K12 strains survive for a relatively long time outside the laboratory. Under the same conditions the isoallelic E. coli K12 relA mutants die faster because they lack the stringent response. The killing rate is increased by using a plasmid-encoded suicide system consisting of the phage T7 lysozyme gene driven by the E. coli alkaline phosphatase gene promoter (phoA). Cells containing this system were rapidly and effectively killed as soon as phosphate was made limiting. The combination of the chromosomal relA mutation and a conditional suicide system of this type provides an effective means of biological containment for recombinant E. coli strains.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050320
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Cadmium biosorption by Streptomyces pimprina waste biomass (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 1118-1121 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Biosorption of cadmium from solution was studied using a hamycin-producing Streptomyces pimprina waste biomass. Mycelial pretreatments with 80% ethanol increased the uptake of cadmium threefold. The rate of uptake of the metal was maximum in the first 10 min and the equilibration of the system was achieved after 60 min. At pH 2.0 there was no adsorption of cadmium; however, as the pH of the solution increased, a rise in the adsorption could be noticed, which peaked at pH 5.0. The uptake of cadmium was found to increase linearly as a function of cadmium concentration up to 500 mg/l. The data could be fitted to Freundlich and Langmuir models for absorption processes. A 0.1 M EDTA solution could desorb cadmium loaded on S. pimprina biomass with the highest efficiency.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166935
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    One-step enzymatic hydrolysis of starch using a recombinant strain of Saccharomyces cerevisiae producing α-amylase, glucoamylase and pullulanase (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 878-883 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A recombinant strain of Saccharomyces cerevisiae was constructed that contained the genes encoding a bacterial α-amylase (AMY1), a yeast glucoamylase (STA2) and a bacterial pullulanase (pulA). The Bacillus amyloliquefaciens α-amylase and S. cerevisiae var. diastaticus glucoamylase genes were expressed in S. cerevisiae using their native promoters and the encoded enzymes secreted under direction of their native leader sequences. In contrast, the Klebsiella pneumoniae pullulanase gene was placed under the control of the yeast alcohol dehydrogenase gene promoter (ADC1 P ) and secreted using the yeast mating pheromone α-factor secretion signal (MFα1 S ). Transcription termination of the pullulanase gene was affected by the yeast tryptophan synthase gene terminator (TRP5 T), whereas termination of the glucoamylase and α-amylase genes was directed by their native terminators. Pullulanase (PUL1) produced by recombinant yeasts containing ADC1 P MFα1 S pulA TRP5T (designated PUL1) was further characterized and compared to its bacterial counterpart (PulA). The different genes were introduced into S. cerevisiae in different combinations and the various amylolytic Saccharomyces transformants compared to Schwanniomyces occidentalis. Introduction of PUL1 into a S. cerevisiae strain containing both STA2 and AMY1, resulted in 99% assimilation of starch
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00191185
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Enzymatic peptide synthesis by the recombinant proline-specific endopeptidase from Flavobacterium meningosepticum and its mutationally altered Cys-556 variant (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 844-852 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Proline-specific endopeptidase (PSE) (EC 3.4.21.26) was investigated for its potential as a catalyst in peptide synthesis. Using an activated peptide ester or a peptide amide as the acyl component, the enzyme catalyzed kinetically controlled aminolysis and transpeptidation respectively, with various amino acid amides as acyl acceptors. To a certain extent the nucleophile preference reflected the amino acid preference in the S1′-position of the enzyme in peptide hydrolysis: the highest fractions of aminolysis were obtained using amino acid amides with hydrophobic side-chains (e.g. Leu-NH2, Phe-NH2). PSE also catalyzed the thermodynamically controlled condensation of short peptides with a free carboxyterminus and various amino acid amides. This enabled us to examine the acceptance of different acyl components in the substrate-binding site of the enzyme with regard to their amino acid composition: In the S1 position proline was clearly favored, but alanine was also accepted, whereas the S2 subsite accepted various amino acids rather unspecifically. Since PSE was shown to be extremely sensitive against water-miscible organic solvents, an alternative approach was used to increase yields in enzymatic peptide synthesis: a derivative of PSE in which the catalytic Ser-556 is converted to a Cys was constructed by protein engineering. This mutant (PSEcys) exhibited a dramatically increased peptide ligase activity in aqueous solution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00191180
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Secretion by Saccharomyces cerevisiae of rat apolipoprotein E as a fusion to Mucor rennin (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 865-870 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract As the first step for production of rat apolipoprotein E (rApoE) in Saccharomyces cerevisiae, the rApoE cDNA was cloned and its nucleotide sequence was determined. When the intact rApoE gene including the presequence-encoding region was expressed under the control of the yeast GAL7 promoter, no protein immunoreactive with anti-rApoE antibody was detected either in the culture medium or inside the cells. For the purpose of the extracellular production of rApoE, three fusion genes were constructed in which the mature rApoE-encoding sequence was connected after the pre, prepro, and whole regions of the gene encoding a fungal aspartic proteinase, Mucor pusillus rennin (MPP), since MPP is efficiently secreted from recombinant S. cerevisiae containing the MPP gene. When these three fusion genes were expressed under the control of the GAL7 promoter, only one, encoding the mature rApoE connected to the whole MPP sequence, directed efficient secretion of the fused protein. The maximum yield of the fused protein secreted into the medium reached 11.8 mg/l and the calculated rApoE part was 5.3 mg in the fused protein. The excreted fusion protein was glycosylated at the original two sites in the MPP part. The fused protein was gradually degraded in the medium probably by proteases of the host cell, because no such degradation occured in a yeast pep4mutant strain.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00191183
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Cloning, DNA sequencing and heterologous expression of the gene for thermostable N-acylamino acid racemase from Amycolatopsis sp. TS-1-60 in Escherichia coli (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 884-889 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The gene encoding the novel enzyme N-acylamino acid racemase (AAR) was cloned in recombinant phage λ-4 from the DNA library of Amycolatopsis sp. TS-1-60, a rare actinomycete, using antiserum against the enzyme. The cloned gene was subcloned and transformed in Escherichia coli JM105 using pUC118 as a vector. The AAR gene consists of an open-reading frame of 1104 nucleotides, which specifies a 368-amino-acid protein with a molecular mass of 39411Da. The molecular mass deduced from the AAR gene is in good agreement with the subunit molecular mass (40kDa) of AAR from Amycolatopsis sp. TS-1-60. The guanosine plus cytosine content of the AAR gene was about 70%. Although the AAR gene uses the unusual initiation codon GTG, the gene was expressed in Escherichia coli using the lac promoter of pUC118. The amount of the enzyme produced by the transformant was 16 times that produced by Amycolatopsis sp. TS-1-60. When the unusual initiation codon GTG was changed to ATG, the enzyme productivity of the transformant increased to more than 37 times that of Amycolatopsis sp. TS-1-60. In the comparison of the DNA sequence and the deduced amino acid sequence of AAR with those of known racemases and epimerases in data bases, no significant sequence homology was found. However, AAR resembles mandelate racemase in that requires metal ions for enzyme activity. Comparison of the deduced amino acid sequences of mandelate racemase and AAR revealed amino acid sequences in AAR similar to those of both the catalytic and metal-ion-binding sites of mandelate racemase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00191186
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Biosynthesis of copolyesters consisting of 3-hydroxybutyric acid and medium-chain-length 3-hydroxyalkanoic acids from 1,3-butanediol or from 3-hydroxybutyrate by Pseudomonas sp. A33 (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 901-909 
    Details
    ISSN: 1432-0614
    Keywords: Polyhydroxyalkanoates 3-hydroxybutyrate ; medium-chain-length 3-hydroxyalkanoates ; 1,3-butanediol Pseudomonas sp. A33 ; polyhydroxyalkanoate synthase polyhydroxyalkanoate depolymerase biodegradable polyesters
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Pseudomonas sp. A33 and other isolates of aerobic bacteria accumulated a complex copolyester containing 3-hydroxybutyric acid (3HB) and various medium-chain-length 3-hydroxyalkanoic acids (3HAMCL) from 3-hydroxybutyric acid or from 1,3-butanediol under nitrogen-limitated culture conditions. 3HB contributed to 15.1 mol/100 mol of the constituents of the polyester depending on the strain and on the cultivation conditions. The accumulated polymer was a copolyester of 3HB and 3HAMCL rather than a blend of poly(3HB) and poly(3HAMCL) on the basis of multiple evidence. 3-Hydroxyhexadecenoic acid and 3-hydroxyhexadecanoic acid were detected as constituents of polyhydroxyalkanoates, which have hitherto not been described, by13C nuclear magnetic resonance or by gas chromatography/mass spectrometric analysis. In total, ten different constituents were detected in the polymer synthesized from 1,3-butanediol by Pseudomonas sp. A33:besides seven saturated (3HB, 3-hydroxyhexanoate, 3-hydroxyoctanoate, 3-hydroxydecanoate, and 3-hydrohexadecanoate) three unsaturated (3-hydroxydodecenoate, 3-hydroxytetradecenoate and 3-hydrohexadecanoate) hydroxyalkanoic acid constituents occured. The polyhydroxyalkanoate synthase of Pseudomonas sp. A33 was cloned, and its substrate specificity was evaluated by heterologous expression in various strains of P. putida, P. oleovorans and Alcaligenes eutrophus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00191189
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Maltose-fructose co-fermentation by Lactobacillus brevis subsp. lindneri CB1 fructose-negative strain (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 939-944 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The Lactobacillus brevis subsp. lindneri CB1 fructose-negative strain utilized fructose in co-fermentation with maltose or glucose. Compared to the maltose (17 g/l) fermentation, the simultaneous fermentation of maltose (10 g/l) and fructose (7 g/l) increased cell yield (A 620from 2.6 to 3.3) and the concentrations of lactic acid and especially of acetic acid (from 2.45 g/l to 3.90 g/l), produced mannitol (1.95 g/l) and caused a decrease in the amount of ethanol (from 0.46 g/l to 0.08 g/l). The utilization of fructose depended on the continuous presence of maltose in the growth medium and the two carbohydrates were consumed in a molar ratio of about 2:1. The presence of tagatose (a fructose stereoisomer) partially inhibited fructose consumption and consequently caused a decrease of the end products of the co-metabolism. Since maltose was naturally present during sourdough fermentation, the addition of only 6 g fructose/kg wheat dough enabled the co-fermentation of maltose and fructose by L. brevis subsp. lindneri CB1. A higher titratable acidity and acetic acid concentration, and a reduced quotient of fermentation (2.7) were obtained by co-fermentation compared with normal sourdough fermentation. Some interpretations of the maltose-fructose co-fermentation are given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00191194
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Acknowledgement to reviewers 1994 (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 969-971 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00191199
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Biodegradation of 2-chloroethanol by freely suspended and adsorbed immobilized Pseudomonas putida US2 in soil (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 143-149 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The degradation of 2-chloroethanol by Pseudomonas putida US2 was investigated in batch, repeated batch and continuous cultures especially in a packed-bed fermenter with sand. The degradation of 2-chloroethanol was connected with a release of protons, which led to a decrease of the pH in the medium. Higher initial concentration than 25 mM 2-chloroethanol were not degraded completely because they entailed a decrease of the pH to 5.0, which inhibited further growth and degradation. P. putida US2 showed a typical repression of catabolites and diauxic growth with succinate as cosubstrate. The addition of succinate as a second substrate caused a decrease in degradation of 2-chloroethanol. Activated sludge added to adsorbed cultures in a continuous fermentation did not lead to a decrease in metabolic activity. After 2 weeks of continuous cultivation the specialized strain could be retained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00170636
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Kinetics of bio-oxidation of a medium comprising phenol and a mixture of organic contaminants (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 165-170 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The kinetics of bio-oxidation by a microbial ensemble of a model mixture of contaminants that mimicked the ground-water pollution plume at an existing contaminated site was investigated. Phenol at 50 mg/l and a mixture of ten organic contaminants (MOC) (benzene, tetrachloromethane, trichloroethylene, toluene, o-xylene, 1,4-dichlorobenzene, o-cresol, nitrobenzene, naphthalene and 2,6-dichlorophenol) at individual concentrations ranging from 150 μg/l to 600 μg/l were the components of the model mixture. The microbial ensemble consisted of at least three Pseudomonas spp. isolated from the polluted site. Patterns of oxygen uptake rate (OUR) for the oxidation of phenol alone and with added MOC were treated mathematically. The values for kinetic parameters that gave the best fit to the data were respectively 11.29 and 15.03 ml O2 h−1 (mg protein)−1 for the OUR maximum (OURmax), 75.89 mg/l and 33.66 mg/l for the saturation constant (K s), 105.92 mg/l and 36.44 mg/l for the inhibitor constant (K i), and 89.66 mg/l and 35.02 mg/l the substrate minimum inhibitory concentration (S mic). This study also scrutinised interference between the two components of the model mixture of contaminants (phenol and MOC) on the basis of variations in kinetic patterns. MOC was shown to be toxic at milligram per litre levels. The microbial ensemble increased phenol oxidation in response to MOC, possibly to obtain the energy to overcome this toxic effect. This was indicated by an acceleration of phenol oxidation in response to increasing concentrations of MOC and higher OURmax for oxidation of phenol in the presence of MOC. The toxicity of MOC also resulted in enhanced vulnerability of the microbial ensemble to a phenol inhibitory effect, indicated by the diminution of K i and S mic. The microbial ensemble showed high resistance to inhibition by the sole presence of phenol possibly because of adaptation to toxic features of MOC during the processes of enrichment and cultivation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00170639
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Kinetics of a fluidized-bed reactor for ground-water denitrification (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 188-193 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A fluidized-bed reactor, with sand as the carrier and ethanol as the carbon and electron source, was investigated for the biological denitrification of ground water. The paper concentrates on the reactor's kinetics, with special emphasis on nitrite as the intermediate product. Intrinsic zero-order kinetic parameters for both nitrate and nitrite were determined by batch and continuous experiments. Values for the maximum specific nitrate and nitrite removal rates of 11 g and 6 g NO inf3 sup− (g volatile suspended solids)−1 day−1, respectively, were obtained. These values were used to interpret nitrate and nitrate concentration profiles in an experimental fluidized-bed reactor operating at different conditions of hydraulic loading and retention time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00170642
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Mixed photo-cross-linked polyvinyl alcohol and calcium-alginate gels for cell entrapment (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 10-17 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Living cells may be immobilized by gel entrapment under very mild conditions. The ionotropic gelation of alginate with bivalent cations such as Ca2+, as well as photo-induced gelation of polyvinyl alcohol (PVA) bearing photosensitive stilbazolium (SbQ) groups, are procedures that are compatible with most bioactive materials. In the search for more stable and stronger alginate gel beads, experiments have been carried out to investigate mixed gels from alginate and PVA-SbQ. The swelling capacities, diffusion properties, and potential toxic effect of the binary gel beads have been evaluated. The gel beads of selected PVA-SbQ/alginate mixtures were applied successfully as carriers in a denitrification process with continuous feeding of unsterilized water medium. Under such conditions, the purely synthetic PVA-SbQ network is expected to have a longer lifespan than a natural biopolymer such as alginate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050362
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Ethanol tolerance of immobilized brewers’ yeast cells (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 18-24 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  A method based on the survival of yeast cells subjected to an ethanol or heat shock was utilized to compare the stress resistance of free and carrageenan-immobilized yeast cells. Results demonstrated a significant increase of yeast survival against ethanol for immobilized cells as compared to free cells, while no marked difference in heat resistance was observed. When entrapped cells were released by mechanical disruption of the gel beads and submitted to the same ethanol stress, they exhibited a lower survival rate than entrapped cells, but a similar or slightly higher survival rate than free cells. The incidence of ethanol- or heat-induced respiratory-deficient mutants of entrapped cells was equivalent to that of control or non-stressed cells (1.3±0.5%) whereas ethanol- and heat-shocked free and released cells exhibited between 4.4% and 10.9% average incidence of respiration-deficient mutants. It was concluded that the carrageenan gel matrix provided a protection against ethanol, and that entrapped cells returned to normal physiological behaviour as soon as they were released. The cell growth rate was a significant factor in the resistance of yeast to high ethanol concentrations. The optimum conditions to obtain reliable and reproducible results involved the use of slow-growing cells after exhaustion of the sugar substrate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050363
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Conversion of D-sorbit to L-sorbose by cells of Acetobacter suboxydans immobilized in sintered glass (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 35-37 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A simple method for immobilizing cells of Acetobacter suboxydans by adsorption on inorganic sintered glass carriers is described. The immobilized cell preparations exhibited 100% of the initial activity when converting D-sorbit to L-sorbose. This sintered glass was used in a fixed-bed loop reactor with a working volume of 0.2 l for semicontinuous and continuous experiments. A prolonged working life span was achieved, which could possibly satisfy requirements for scaled-up operations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050366
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Lipase from Pseudomonas fragi CRDA 323: Partial purification, characterization and interesterification of butter fat (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 42-51 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Several strains of Pseudomonas were screened for lipase production using the rhodamine agar diffusion test. On the basis of the diameter of the halo produced, P.  fragi CRDA 323 and P. putida ATCC 795 were considered to be good and weak lipase producers respectively. P.  fragi, cultured in a 2-l fermenter, produced a maximal amount of lipase after 3–4 days of incubation at 27°C. The lipase extract of P.  fragi was obtained by acidification of culture supernatant at pH 4.0 and partially purified with ammonium sulphate precipitation. The majority of lipase activity (42%) was located in fraction IV, precipitated at 20%–40% of saturation, with a 19-fold enzyme purification. The K m and V max values for the partially purified enzymatic extract (fraction IV) were 0.70 mg/ml and 0.97×10-3 U/min respectively. Fraction IV, which showed an optimum activity at pH 8.5, was used for the interesterification of butter fat in a microemulsion free co-surfactant system containing Span 60 (sorbitol monostearate) and Tween 60 (polyoxyethylene sorbitan monostearate) in the ratio 48:52 (v/v). The results showed that the interesterification of butter fat resulted in a considerable decrease in long-chain saturated fatty acids (C12:0, C14:0 and C16:0) with a concomitant increase in C18:0 and C18:1 at the sn-2 position of selected triacylglycerols. In addition, the results demonstrated an increase in the fatty acids (C12:0, C14:0 and 16:0) among the 1 and 3 positions of the triacylglycerol molecules of modified buffer fat accompanied by a decrease in C18:0 and C18:1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050368
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Improved strains of recombinant Escherichia colifor ethanol production from sugar mixtures (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 70-75 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Hemicellulose hydrolysates of agricultural residues often contain mixtures of hexose and pentose sugars. Ethanologenic Escherichia coli that have been previously investigated preferentially ferment hexose sugars. In some cases, xylose fermentation was slow or incomplete. The purpose of this study was to develop improved ethanologenic E. coli strains for the fermentation of pentoses in sugar mixtures. Using fosfomycin as a selective agent, glucose-negative mutants of E. coli KO11 (containing chromosomally integrated genes encoding the ethanol pathway from Zymomonas mobilis) were isolated that were unable to ferment sugars transported by the phosphoenolpyruvate-dependent phosphotransferase system. These strains (SL31 and SL142) retained the ability to ferment sugars with independent transport systems such as arabinose and xylose and were used to ferment pentose sugars to ethanol selectively in the presence of high concentrations of glucose. Additional fosfomycin-resistant mutants were isolated that were superior to strain KO11 for ethanol production from hexose and pentose sugars. These hyperproductive strains (SL28 and SL40) retained the ability to metabolize all sugars tested, completed fermentations more rapidly, and achieved higher ethanol yields than the parent. Both SL28 and SL40 produced 60 g l-1 ethanol from 120 g l-1 xylose in 60 h, 20% more ethanol than KO11 under identical conditions. Further studies illustrated the feasibility of sequential fermentation. A mixture of hexose and pentose sugars was fermented with near theoretical yield by SL40 in the first step followed by a second fermentation in which yeast and glucose were added. Such a two-step approach can combine the attributes of ethanologenic E. coli for pentoses with the high ethanol tolerance of conventional yeasts in a single vessel.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050372
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Use of Congo red as a microscopic fluorescence indicator of hyphal growth (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 102-108 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Congo red was found to be feasible as a microscopic fluorescence indicator of hyphal growth at the single-hypha level. When 1 μM Congo red was applied to mold of Aspergillus niger, the dye was found to a specific cell-wall component, chitin, without causing any inhibitory effect on hyphal growth. The bound Congo red emitted fluorescence at 614 nm. This binding reaction, however, proceeded more slowly than the growing speed of hypha. Consequently the fluorescence intensity was low at the apex where the surface area of the hypha was expanding rapidly. In contrast, as an apex where the growth was retarded, the fluorescence intensity became remarkably high. Therefore growing hyphae could be distinguished from non-growing hyphae by using Congo red.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050377
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    The lysins of bacteriophages infecting lactic acid bacteria (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 1-6 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract This short review highlights the complete absence of literature on lysins of bacteriophages infecting species like S. salivarius subsp. thermophilus, Pediococcus and Leuconostoc species, L. helveticus, L. acidophilus, L. plantarum and L. brevis, which are also widely used in the dairy industry. The lysins described share some similar biochemical characteristics: optimal pH and temperature, site of hydrolysis inside the peptidoglycan, and some activators and inhibitors. The cloning of the genes encoding these lysins only began in the last few years and four of them have been completely sequenced. In the future, these lysin genes could be interestingly compared to the host autolysin(s) gene(s). By contrast, the passage of phage lysins through the cytoplasmic membrane of the host cell in order to reach the peptidoglycan (via a signal sequence or the presence of a holin) seems not to be clearly resolved. The presence of a second open-reading frame upstream from the gene of the lysin, enabling a putative holin to be encoded, has already been suggested. No doubt our ever increasing knowledge about bacteriophage genome organization will help to elucidate this question. Meanwhile the obtention of a Lactococcus strain with an autolytic phenotype, using a bacteriophage lysin gene, as well as the successful use of purified PL1 lysin to obtain protoplasts of L. casei encourage us to continue to explore the field of bacteriophage lysins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00170613
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Bioconversion of substituted naphthalenes to the corresponding 1,2-dihydro-1,2-dihydroxy derivatives. Determination of the regio- and stereochemistry of the oxidation reactions (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 306-313 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A mutant (TTC1) derived from Pseudomonas fluorescens N3 has been obtained for use in the bioconversion of several naphthalene derivatives to the corresponding optically active cis-dihydrodiols on a milligrams-to-grams scale. All main compounds have been characterized, their relative and absolute configuration assigned, and their enantiomeric purity determined. The regio- and stereoselectivity of the transformation has been established. The procedure therefore represents a valid method for the convenient preparation of a pool of valuable chiral syntons and auxiliaries.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050559
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Biosynthesis of extracellular low-molecular-mass papain and trypsin inhibitors by Streptomyces sp. 22: effect of cultural conditions (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 131-136 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The production of extracellular inhibitors of papain and trypsin by Streptomyces sp. 22 was studied under different cultural conditions including complex and defined media, temperatures ranging from 18 °C to 37 °C and a variety of sole carbon and nitrogen sources. In complex nutritionally rich medium, maximal specific growth rates were obtained at 37 °C, whereas the highest specific production rates for both papain and trypsin inhibitors were registered at 18 °C. Studies on the effect of different carbon and nitrogen sources in defined media underline the importance of the nitrogen source as a strong regulator of the biosynthesis of both inhibitors. Enhanced formation of the inhibitory compounds occurred in the presence of casein. The dynamics of the formation of both inhibitors in defined media showed close association with growth. However, a partial separation of production phases for papain and trypsin inhibitors was observed in complex medium. The results imply differences in the regulation of biosynthesis of the two inhibitors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050381
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Development of a continuous system for the degradation of a cyanuric acid by adsorbed Pseudomonas sp. NRRL B-12228 (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 150-155 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Cyanuric acid in high concentrations (15.5 mM) was degraded completely by Pseudomonas sp. NRRL B-12228 independently of glucose concentration. In the batch fermentations there was a relation between the glucose concentration, on the one hand, and the liberation of ammonia or production of protein, on the other. The greater the supply of carbon, the more biomass was produced, and fewer NH+ 4 ions were released. Continuous fermentations using adsorbed cells could be performed to degrade cyanuric acid. In spite of different glucose feeding there was only a negligible difference in residues of s-triazine. In a one-step continuous system with dilution rates between 0.021 h-1 and 0.035 h-1, even a ratio of 0.65 between glucose and cyanuric acid was not sufficient to degrade the cyanuric acid supplied (320–540 μmol l-1 h-1) completely. When a continuous two-step system was applied with dilution rates between 0.035 h-1 and 0.056 h-1, the consumption of carbon source could be minimized while s-triazine degradation up to 860 μmol l-1 h-1 was complete. In this way the ratio between glucose and cyanuric acid could be increased to 0.25 (molar C:N ratio=0.33:1). Thereby the process was made considerably more economic.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050384
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    Influence of organic and inorganic growth supplements on the aerobic biodegradation of chlorobenzoic acids (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 171-177 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The effect of yeast extract and its less complex substituents on the rate of aerobic dechlorination of 2-chlorobenzoic acid (2-ClBzOH) and 2,5-dichlorobenzoic acid (2,5-Cl2BzOH) by Pseudomonas sp. CPE2 strain, and of 3-chlorobenzoic acid (3-ClBzOH), 4-chlorobenzoic acid (4-ClBzOH) and 3,4-dichlorobenzoic acid (3,4-Cl2BzOH) by Alcaligenes sp. CPE3 strain were investigated. Yeast extract at 50 mg/l increased the average dechlorination rate of 200 mg/l of 4-ClBzOH, 2,5-Cl2BzOH, 3,4-Cl2BzOH, 3-ClBzOH and 2-ClBzOH by about 75%, 70%, 55%, 7%, and 1%, respectively. However, in the presence of yeast extract the specific dechlorination activity of CPE2 and CPE3 cells (per unit biomass) was always lower than without yeast extract, although it increased significantly during the exponential growth phase. When a mixed vitamin solution or a mixed trace element solution was used instead of yeast extract the rate of 4-ClBzOH dechlorination increased by 30%–35%, whereas the rate of 2,5-Cl2BzOH and 3,4-Cl2BzOH dechlorination increased by only 2%–10%. The presence of vitamins or trace elements also resulted in a specific dechlorination activity that was generally higher than that observed for the same cells grown solely on chlorobenzoic acid. The results of this work indicate that yeast extract, a complex mixture of readily oxidizable car- bon sources, vitamins, and trace elements, enhances the growth and the dechlorination activity of CPE2 and CPE3 cells, thus resulting in an overall increase in the rate of chlorobenzoic acid utilization and dechlorination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050387
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Biosynthesis of poly-3-hydroxybutyrate by Sphaerotilus natans (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 31-34 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A sheathed bacterium Sphaerotilus natans could not survive at 4°C for 2 months, and mutants that exhibited different colony phenotypes were obtained only by repeating the short period of storage at 4 °C. The ability of these mutants and the parent strain to produce poly-3-hydroxybutyrate (PHB) was compared in batch cultures. The parent strain accumulated 30% (w/w) PHB, while one of the mutants defective in sheath formation, designated as T2, accumulated over 50% PHB. Because T2 did not require strict air or nitrogen limitation for polymer accumulation, its production was growth-associated, allowing one-stage fermentation. In a pH-controlled fermentation using a jar fermentor, 10 g/l glucose was converted into 2.0 g/l PHB in 24 h.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00170618
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Thermophilic anaerobic amino acid degradation: deamination rates and end-product formation (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 235-241 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Anaerobic thermophilic degradation of several amino acids was studied in batch cultures using an inoculum from a steady-state semicontinuous enrichment culture. Experiments were done in the presence and absence of methanogenesis and known electron acceptors in the Stickland reaction. Methanogenesis was found to be crucial for the degradation of amino acids known to be oxidatively deaminated (leucine, valine and alanine). Other amino acids (serine, threonine, cysteine and methionine) were degraded under both methanogenic and non-methanogenic conditions. Degradation rates for these four amino acids were 1.3 to 2.2 times higher in cases where methanogenesis was active. The degradation rates of serine, threonine, cysteine and methionine were about twice as high as the rates of leucine, valine and alanine under methanogenic conditions. Inclusion of different electron acceptors, known to work in the Stickland reaction, did not enhance the degradation rates of any amino acid used nor did they alter the degradation patterns. Glycine was oxidatively deaminated to acetate, carbon dioxide, hydrogen and ammonium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00172818
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Effects of shear flow on photosynthesis in a dilute suspension of microalgae (1995)
    Springer
    Applied microbiology and biotechnology 42 (1995), S. 744-749 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract This study investigates the effects of shear stress on photosynthesis in dilute suspensions of Spirulina platensis and Chlorella by measuring the oxygen production rate using a coaxial, double-rotating-cylinder apparatus that generates Couette shear flow. Our device enables up to 0.6 Pa shear stress to be applied, which has the hydrodynamic effect of generating the algal motion and acutely augmenting the oxygen production rate of Spirulina, primarily because the surface area of algae exposed to illumination is increased. However, there is shear-flow limitation on any increase in oxygen production, and the shear stress at maximum oxygen production rate tends to decrease with increasing temperature. The comparative study with Chlorella showed the reverse relationship between oxygen production and shear stress, and the cause of this difference is discussed in terms of several factors such as size, shape, hydrodynamic stress capacity and others.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00171956
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Thermostable d-hydantoinase from thermophilic Bacillus stearothermophilus SD-1: characteristics of purified enzyme (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 270-276 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract One thousand thermophiles isolated from soils were screened for hydantoinase and its thermostability. One thermophilic bacterium that showed the highest thermostability and activity of hydantoinase was identified to be Bacillus stearothermophilus SD-1 according to morphological and physiological characteristics. The hydantoinase of B. stearothermophilus SD-1 was purified to homogeneity via ammonium sulfate fractionation, anion-exchange chromatography, heat treatment, hydrophobic-interaction chromatography, and preparative gel electrophoresis. The relative molecular mass of the hydantoinase was determined to be 126 kDa by gel-filtration chromatography, and a value of 54 kDa was obtained as a molecular mass of the subunit on analytical sodiumdodecylsulfate/polyacrylamide gel electrophoresis. The hydantoinase was strictly d-specific and metal-dependent. The optimal pH and temperature were about 8.0 and 65°C respectively, and the half-life of the d-hydantoinase was estimated to be 30 min at 80°C, indicating the most thermostable enzyme so far.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00172823
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Expression of cho and melC operons by a Streptococcus thermophilus synthetic promoter in Escherichia coli (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 285-290 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A 63-base-pair synthetic promoter, sP1, was synthesized on the basis of the nucleotide sequence of a putative Streptococcus thermophilus promoter. When inserted upstream from the Streptomyces cho operon in a recombinant plasmid, pUCO195P-36, sP1 activated the expression of the cho genes in Escherichia coli, as shown by the production of cholesterol oxidase by the transformants. The sP1-driven cholesterol oxidase production in pUCO195P-36-transformed cells was estimated to be 40% of that produced by Plac-mediated cho expression in a pUCO193-containing host. The recombinant pUCO195P-36 appeared to be segregationally less stable in E. coli DH5α than in HB101. Its non-expressing counterpart, pUCO195P-1, was stable in both E. coli strains. The activity of sP1 was further demonstrated in E. coli by the expression of a Streptomyces melC operon. When placed upstream from the test operon in the pMCU22aPa construct, sP1 activated the melC expression as shown by the production of tyrosinase at (3.0±0.3) × 10−3 U/mg and (16.0±1.0) × 10−3 U/mg protein equivalent of cell extract in the absence and presence of isopropyl β-d-thio-galactopyranoside, respectively. The presence of a counter-oriented Plac at the 3′ end of the operon in the pMCU22bPa plasmid reduced the sP1-mediated tyrosinase production by about 85%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00172826
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Kinetic parameters for hydrogen evolution by the NAD-linked hydrogenase of Alcaligenes eutrophus (1995)
    Springer
    Applied microbiology and biotechnology 44 (1995), S. 514-518 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  The hydrogen-evolving reaction of the purified soluble NAD-linked hydrogenase of Alcaligenes eutrophus was used to determine kinetic parameters of the enzyme. The H2-evolving activity with methyl viologen as electron mediator was 20-fold as compared to that with NADH. In the assay with dithionite-reduced methyl viologen (K m 0.7 mM) the hydrogenase was most active at a redox potential of −560 mV and exhibited a pH optimum of 7.0. The K m for protons, the second substrate for H2 evolution, was 6.2 nM. With electrochemically reduced methyl viologen the pH optimum was shifted to pH 6.0. Double-reciprocal plots of reaction rates versus proton concentrations intercepted at the ordinate for different methyl viologen concentrations. At different pH values such an intercept was also observed with the dye as the varied substrate. The kinetic data are diagnostic for an ordered bisubstrate mechanism where both substrates are bound before the product H2 is released. Hydrogenase coupled to thylakoid membranes resulted in a constant H2 evolution rate over 6 h. The system appeared to be limited by the capacity of the thylakoid membranes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050591
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Influence of pH, malic acid and glucose concentrations on malic acid consumption by Saccharomyces cerevisiae (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 321-324 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Malic acid consumption by Saccharomyces cerevisiae was studied in a synthetic medium. The extent of malic acid degradation is affected by its initial concentration, the extent and the rate of deacidification increased with initial malate concentration up to 10 g/l. For malic acid consumption, an optimal pH range of 3–3.5 was found, confirming that non-dissociated organic acids enter S. cerevisiae cells by simple diffusion. A full factorial design has been employed to describe a statistical model of the effect of sugar and malic acid on the quantity of malate degraded (g/l) by a given amount of biomass (g/l). The results indicated that the initial malic acid concentration is very important for the ratio of malate consumption to quantity of biomass. The yeast was found to be most efficient at higher levels of malate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00172832
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Anaerobic digestion of cattle waste at mesophilic and thermophilic temperatures (1995)
    Springer
    Applied microbiology and biotechnology 43 (1995), S. 346-350 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Methanogenesis was studied using stirred, bench-top fermentors of 3-1 working volume fed on a semi-continuous basis with waste obtained from cattle fed a high grain, finishing diet. Digestion was carried out at 40 and 60°C. CH4 production was 11.8, 18.3, 61.9 and 84.5% higher in the thermophilic than the mesophilic digestor at the 3, 6, 9 and 12 g volatile solids (VS) l−1 reactor volume loading rates, respectively. When compared on an energetic basis CH4 production was 7.4, 18.3, 72.9 and 107.3 kJ day higher in the thermophilic than the mesophilic digestor. CH4 production decreased more rapidly with each increase in VS loading rate and decrease in retention time (RT) in the mesophilic than the thermophilic digestor. When expressed as l g−1 VS fed or as kJ kJ−1 fed, the amount of CH4 was 49% less at the highest compared to the lowest loading rate in the mesophilic digestor. In the thermophilic digestor the decrease was only 16%. Propionate accumulated in the mesophilic digestor at the two highest loading rates, reaching concentrations of about 50 mM, but were only about 13 mM in the thermophilic digestor. Isobutyrate, isovalerate plus 2-methylbutyrate, and valerate also accumulated at the higher loading rates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00172837
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...