ALBERT

Description:    White-rot fungi are a group of microorganisms capable of degrading xenobiotic compounds, such as polycyclic aromatic hydrocarbons or synthetic dyes, by means of the action of extracellular oxidative enzymes secreted during secondary metabolism. In this study, the transformation of three anti-inflammatory drugs: diclofenac, ibuprofen and naproxen were carried out by pellets of Phanerochaete chrysosporium in fed-batch bioreactors operating under continuous air supply or periodic pulsation of oxygen. The performance of the fungal reactors was steady over a 30-day treatment and the effect of oxygen pulses on the pellet morphology was evidenced. Complete elimination of diclofenac was achieved in the aerated and the oxygenated reactors, even with a fast oxidation rate in the presence of oxygen (77% after 2 h), reaching a total removal after 23 h. In the case of ibuprofen, this compound was completely oxidized under air and oxygen supply. Finally, naproxen was oxidized in the range of 77 up to 99% under both aeration conditions. These findings demonstrate that the oxidative capability of this microorganism for the anti-inflammatory drugs is not restricted to an oxygen environment, as generally accepted, since the fungal reactor was able to remove these compounds under aerated and oxygenated conditions. This result is very interesting in terms of developing viable reactors for the oxidation of target compounds as the cost of aeration can be significantly reduced. Content Type Journal Article Pages 1-12 DOI 10.1007/s10532-011-9494-9 Authors A. I. Rodarte-Morales, Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain G. Feijoo, Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain M. T. Moreira, Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain J. M. Lema, Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    In this work, two novel iron oxidizing bacteria (IOB), namely Gordonia sp. MZ-89 and Enterobacter sp . M01101, were isolated from sewage treatment plants and identified by biochemical and molecular methods. Then, microbially influenced corrosion (MIC) of carbon steel in the presence of these bacteria was investigated. The electrochemical techniques such as potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS) were used to measure the corrosion rate and observe the corrosion mechanism. The results showed that the existence of these microorganisms decreased the corrosion potential and enhanced the corrosion rate. Scanning electron microscopy (SEM) images revealed the ground boundary attacks and pitting on carbon steel samples in the presence of these bacteria after polarization. Corrosion scales were identified with X-ray diffraction (XRD). It was demonstrated that these bacteria can greatly affect the crystalline phase of corrosion products that also confirmed by SEM results. It was inferred that these bacteria were responsible for the corrosion of carbon steel, especially in the form of localized corrosion. Content Type Journal Article Pages 1-11 DOI 10.1007/s10532-011-9487-8 Authors H. Ashassi-Sorkhabi, Electrochemistry Research Laboratory, Physical Chemistry Department, Faculty of Chemistry, University of Tabriz, Tabriz, Iran M. Moradi-Haghighi, Electrochemistry Research Laboratory, Physical Chemistry Department, Faculty of Chemistry, University of Tabriz, Tabriz, Iran G. Zarrini, Microbiology Laboratory, Biology Department, Science Faculty, University of Tabriz, Tabriz, Iran R. Javaherdashti, Department of Civil Engineering, Curtin University of Technology, Perth, WA, Australia Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    The common grass Calamagrostis epigeions produces a large amount of dead biomass, which remain above the soil surface for many months. In this study, we determined how exposure of dead biomass above the soil affects its subsequent decomposition in soil. Collected dead standing biomass was divided in two parts, the first one (initial litter) was stored in a dark, dry place. The other part was placed in litterbags in the field. The litterbags were located in soil, on the soil surface, or hanging in the air without contact with soil but exposed to the sun and rain. After 1 year of field exposure, litter mass loss and C and N content were measured, and changes in litter chemistry were explored using NMR and thermochemolysis-GC–MS. The potential decomposability of the litter was quantified by burying the litter from the litterbags and the initial litter in soil microcosms and measuring soil respiration. Soil respiration was greater with litter that had been hanging in air than with all other kinds of litter. These finding could not be explained by changes in litter mass or C:N ratio. NMR indicated a decrease in polysaccharides relative to lignin in litter that was buried in soil but not in litter that was placed on soil surface or that was hanging in the air. Thermochemolysis indicated that the syringyl units of the litter lignin were decomposed when the litter was exposed to light. We postulate that photochemical decay of lignin increase decomposability of dead standing biomass. Content Type Journal Article Pages 1-8 DOI 10.1007/s10532-011-9479-8 Authors Jan Frouz, Faculty of Science, Institute for Environmental Studies, Charles University, Benátská 2, 12800 Praha, Czech Republic Tomáš Cajthaml, Faculty of Science, Institute for Environmental Studies, Charles University, Benátská 2, 12800 Praha, Czech Republic Ondřej Mudrák, Institute of soil biology, Biology Center, AS CR, Na Sádkách 7, 37005 České Budějovice, Czech Republic Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    Arsenic is a carcinogenic compound widely distributed in the groundwater around the world. The fate of arsenic in groundwater depends on the activity of microorganisms either by oxidizing arsenite (As III ), or by reducing arsenate (As V ). Because of the higher toxicity and mobility of As III compared to As V , microbial-catalyzed oxidation of As III to As V can lower the environmental impact of arsenic. Although aerobic As III -oxidizing bacteria are well known, anoxic oxidation of As III with nitrate as electron acceptor has also been shown to occur. In this study, three As III -oxidizing bacterial strains, Azoarcus sp. strain EC1-pb1, Azoarcus sp. strain EC3-pb1 and Diaphorobacter sp. strain MC-pb1, have been characterized. Each strain was tested for its ability to oxidize As III with four different electron acceptors, nitrate, nitrite, chlorate and oxygen. Complete As III oxidation was achieved with both nitrate and oxygen, demonstrating the novel ability of these bacterial strains to oxidize As III in either anoxic or aerobic conditions. Nitrate was only reduced to nitrite. Different electron donors were used to study their suitability in supporting nitrate reduction. Hydrogen and acetate were readily utilized by all the cultures. The flexibility of these As III -oxidizing bacteria to use oxygen and nitrate to oxidize As III as well as organic and inorganic substrates as alternative electron donors explains their presence in non-arsenic-contaminated environments. The findings suggest that at least some As III -oxidizing bacteria are flexible with respect to electron-acceptors and electron-donors and that they are potentially widespread in low arsenic concentration environments. Content Type Journal Article Pages 1-11 DOI 10.1007/s10532-011-9493-x Authors Lucía Rodríguez-Freire, Department of Chemical and Environmental Engineering, University of Arizona, P.O. Box 210011, Tucson, AZ, USA Wenjie Sun, Department of Chemical and Environmental Engineering, University of Arizona, P.O. Box 210011, Tucson, AZ, USA Reyes Sierra-Alvarez, Department of Chemical and Environmental Engineering, University of Arizona, P.O. Box 210011, Tucson, AZ, USA Jim A. Field, Department of Chemical and Environmental Engineering, University of Arizona, P.O. Box 210011, Tucson, AZ, USA Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    To reduce the volume of seaweed wastes and extract polysaccharides, seaweed-degrading bacteria were isolated from drifting macroalgae harvested along the coast of Toyama Bay, Japan. Sixty-four bacterial isolates were capable of degrading “Wakame” ( Undaria pinnatifida ) thallus fragments into single cell detritus (SCD) particles. Amongst these, strain 6532A was the most active degrader of thallus fragments, and was capable of degrading thallus fragments to SCD particles within a day. Although the sequence similarity of the 16S rRNA gene of strain 6532A was 100% similar to that of Microbulbifer elongatus JAMB-A7, several distinct differences were observed between strains, including motility, morphology, and utilization of d -arabinose and gelatin. Consequently, strain 6532A was classified as a new Microbulbifer strain, and was designated Microbulbifer sp. 6532A. Strain 6532A was capable of degrading both alginate and cellulose in the culture medium, zymogram analysis of which revealed the presence of multiple alginate lyases and cellulases. To the best of our knowledge, this is the first study to directly demonstrate the existence of these enzymes in Microbulbifer species. Shotgun cloning and sequencing of the alginate lyase gene in 6532A revealed a 1,074-bp open reading frame, which was designated algMsp . The reading frame encoded a PL family seven enzyme composed of 358 amino acids (38,181 Da). With a similarity of 74.2%, the deduced amino acid sequence was most similar to a Saccharophagus enzyme ( alg 7C ). These findings suggest that algMsp in strain 6532A is a novel alginate lyase gene. Content Type Journal Article Pages 1-13 DOI 10.1007/s10532-011-9489-6 Authors Masayuki Wakabayashi, Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555 Japan Akihiro Sakatoku, Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555 Japan Fumio Noda, Sugiyo Co. Ltd, Nanao, Ishikawa 926-8603, Japan Minoru Noda, Sugiyo Co. Ltd, Nanao, Ishikawa 926-8603, Japan Daisuke Tanaka, Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555 Japan Shogo Nakamura, Graduate School of Science and Engineering, University of Toyama, Toyama, 930-8555 Japan Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    The performance of an Arthrobacter viscosus culture to remove diethylketone from aqueous solutions was evaluated. The effect of initial concentration of diethylketone on the growth of the bacteria was evaluated for the range of concentration between 0 and 4.8 g/l, aiming to evaluate a possible toxicological effect. The maximum specific growth rate achieved is 0.221 h −1 at 1.6 g/l of initial diethylketone concentration, suggesting that for higher concentrations an inhibitory effect on the growth occurs. The removal percentages obtained were approximately 88%, for all the initial concentrations tested. The kinetic parameters were estimated using four growth kinetic models for biodegradation of organic compounds available in the literature. The experimental data found is well fitted by the Haldane model ( R 2  = 1) as compared to Monod model ( R 2  = 0.99), Powell ( R 2  = 0.82) and Loung model ( R 2  = 0.95). The biodegradation of diethylketone using concentrated biomass was studied for an initial diethylketone concentration ranging from 0.8–3.9 g/l in a batch with recirculation mode of operation. The biodegradation rate found followed the pseudo-second order kinetics and the resulting kinetic parameters are reported. The removal percentages obtained were approximately 100%, for all the initial concentrations tested, suggesting that the increment on the biomass concentration allows better results in terms of removal of diethylketone. This study showed that these bacteria are very effective for the removal of diethylketone from aqueous solutions. Content Type Journal Article Pages 1-12 DOI 10.1007/s10532-011-9488-7 Authors Filomena Costa, IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal Cristina Quintelas, IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal Teresa Tavares, IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    Trichloroethylene (TCE) is extensively used in commercial applications, despite its risk to human health via soil and groundwater contamination. The stability of TCE, which is a useful characteristic for commercial application, makes it difficult to remove it from the environment. Numerous studies have demonstrated that TCE can be effectively removed from the environment using bioremediation. Pseudomonas putida F1 is capable of degrading TCE into less hazardous byproducts via the toluene dioxygenase pathway (TOD). Unfortunately, these bioremediation systems are not self-sustaining, as the degradation capacity declines over time. Fortunately, the replacement of metabolic co-factors is sufficient in many cases to maintain effective TCE degradation. Thus, monitoring systems must be developed to predict when TCE degradation rates are likely to decline. Herein, we show evidence that tod expression levels correlate with the ability of P. putida F1 to metabolize TCE in the presence of toluene. Furthermore, the presence of toluene improves the replication of P . putida F1, even when TCE is present at high concentration. These findings may be applied to real world applications to decide when the bioremediation system requires supplementation with aromatic substrates, in order to maintain maximum TCE removal capacity. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s10532-012-9544-y Authors Jianbo Liu, College of Environment and Safety Engineering, Qingdao University of Science and Technology, 53 Zhengzhou Road, Sifang District, Qingdao, 266061 China Takashi Amemiya, Graduate School of Environment and Information Science, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, Yokohama, 240-8501 Japan Qing Chang, Graduate School of Environment and Information Science, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, Yokohama, 240-8501 Japan Yi Qian, College of Environment and Safety Engineering, Qingdao University of Science and Technology, 53 Zhengzhou Road, Sifang District, Qingdao, 266061 China Kiminori Itoh, Graduate School of Engineering, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, Yokohama, 240-8501 Japan Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    Molasses melanoidin (MM) is a major pollutant in biomethanated distillery spent wash (BMDS) due to its recalcitrant properties. The 75% colour and 71% COD of MM (1,000 ppm) were reduced with developed bacterial consortium comprising Proteus mirabilis (IITRM5; FJ581028), Bacillus sp. (IITRM7; FJ581030), Raoultella planticola (IITRM15; GU329705) and Enterobacter sakazakii (IITRM16, FJ581031) in the ratio of 4:3:2:1 within 10 days at optimized nutrient. Bacterial consortium showed manganese peroxidase and laccase activity during MM decolourisation. The dominant growth of R . planticola and E . sakazakii was noted in consortium during MM decolourisation. The comparative GC–MS analysis of extracted compounds of control and degraded samples showed that most of the compounds present in control were completely utilized by bacterial consortium along with production of some metabolites. The developed bacterial consortium could be a tool for the decolourisation and degradation of melanoidin containing BMDS. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s10532-012-9537-x Authors Sangeeta Yadav, Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar University (A Central University), Vidya Vihar, Raebareli Road, Lucknow, 226025 Uttar Pradesh, India Ram Chandra, Department of Environmental Microbiology, Babasaheb Bhimrao Ambedkar University (A Central University), Vidya Vihar, Raebareli Road, Lucknow, 226025 Uttar Pradesh, India Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    The capacity of an anaerobic sediment to achieve the simultaneous biodegradation of phenol and carbon tetrachloride (CT) was evaluated, using humic acids (HA) as redox mediator. The presence of HA in sediment incubations increased the rate of biodegradation of phenol and the rate of dehalogenation (2.5-fold) of CT compared to controls lacking HA. Further experiments revealed that the electron-accepting capacity of HA derived from different organic-rich environments was not associated with their reducing capacity to achieve CT dechlorination. The collected kinetic data suggest that the reduction of CT by reduced HA was the rate-limiting step during the simultaneous biodegradation of phenol and CT. To our knowledge, the present study constitutes the first demonstration of the simultaneous biodegradation of two priority pollutants mediated by HA. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s10532-012-9539-8 Authors Claudia M. Martínez, División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica (IPICyT), Camino a la Presa San José 2055, Col. Lomas 4ª Sección, 78216 San Luis Potosí, SLP, Mexico Luis H. Alvarez, División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica (IPICyT), Camino a la Presa San José 2055, Col. Lomas 4ª Sección, 78216 San Luis Potosí, SLP, Mexico Francisco J. Cervantes, División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica (IPICyT), Camino a la Presa San José 2055, Col. Lomas 4ª Sección, 78216 San Luis Potosí, SLP, Mexico Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820

Description:    Assessing in situ microbial abilities of soils to degrade pesticides is of great interest giving insight in soil filtering capability, which is a key ecosystem function limiting pollution of groundwater. Quantification of pesticide-degrading gene expression by reverse transcription quantitative PCR (RT-qPCR) was tested as a suitable indicator to monitor pesticide biodegradation performances in soil. RNA extraction protocol was optimized to enhance the yield and quality of RNA recovered from soil samples to perform RT-qPCR assays. As a model, the activity of atrazine-degrading communities was monitored using RT-qPCRs to estimate the level of expression of atzD in five agricultural soils showing different atrazine mineralization abilities. Interestingly, the relative abundance of atzD mRNA copy numbers was positively correlated to the maximum rate and to the maximal amount of atrazine mineralized. Our findings indicate that the quantification of pesticide-degrading gene expression may be suitable to assess biodegradation performance in soil and monitor natural attenuation of pesticide. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s10532-012-9574-5 Authors Cécile Monard, UMR CNRS 6553 ‘EcoBio’—IFR2116/FR90 CAREN, Université de Rennes 1, 263 Avenue du Général Leclerc, Bat 14B, 35042 Rennes Cedex, France Fabrice Martin-Laurent, UMR 1347 Agroecologie, AgroSup/INRA/Université de Bourgogne, 17 rue Sully, BP 86510, 21065 Dijon Cedex, France Oscar Lima, UMR CNRS 6553 ‘EcoBio’—IFR2116/FR90 CAREN, Université de Rennes 1, 263 Avenue du Général Leclerc, Bat 14B, 35042 Rennes Cedex, France Marion Devers-Lamrani, UMR 1347 Agroecologie, AgroSup/INRA/Université de Bourgogne, 17 rue Sully, BP 86510, 21065 Dijon Cedex, France Françoise Binet, UMR CNRS 6553 ‘EcoBio’—IFR2116/FR90 CAREN, Université de Rennes 1, 263 Avenue du Général Leclerc, Bat 14B, 35042 Rennes Cedex, France Journal Biodegradation Online ISSN 1572-9729 Print ISSN 0923-9820