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
  • Brackish  (4)
  • Gracilaria verrucosa  (4)
  • Seaweeds  (4)
  • Gracilaria gracilis  (3)
  • 2015-2019  (11)
  • 2005-2009
  • 1980-1984
  • 1
    facet.materialart.
    Unknown
    Effects of depth and initial fragment weights of Gracilaria gracilis on the growth, agar yield, quality, and biochemical composition. (2019)
    Details
    Publication Date: 2021-05-19
    Description: Gracilaria gracilis farming was conducted in the Bizerte lagoon (North of Tunisia) at two depths (0.5 and 2.5 m) using various initial fragment weights (5, 20, and 40 g) in order to investigate the alga growth, agar yield, and quality. IR spectra of agar were performed in comparison to the commercial one. Moreover, the proximate biochemical composition of seaweeds was investigated. The results showed that the highest daily growth rate and agar yield were recorded at 0.5 m, using 5 g as initial fragment weight (5.98 ± 1.98% day−1, 14.87 ± 1.91% dw, respectively). Maximum gel strength was 356.67 ± 15.25 g cm−2 at 2.5 m using an initial weight of 20 g. Gelling and melting temperatures varied from 34.33 ± 0.57 to 35.50 ± 0.57 °C and from 77.00 ± 1.00 to 85.00 ± 0.50 °C, respectively. IR analysis revealed that some spectra were similar, while others were different. The highest dry matter (22.68 ± 1.77%) and ash content (35.25 ± 0.02% of dw) were recorded at 2.5 m, using initial weights of 20 and 5 g, respectively. The maximum carbohydrate and the crude protein contentswere obtained at 0.5m, using 5 g as initialweight (9.52 ± 0.36 and 5.83 ± 0.7% dw, respectively). The highest R-phycoerythrin content was recorded at 0.5m(0.050 ± 0.007 mg g−1 dw), while the maximum of total lipid content was recorded at 2.5 m with initial weight of 5 g (3.58 ± 0.63% dw). Our findings indicated that growth and biochemical composition of G. gracilis depend on the depth and initial fragment weights.
    Description: In Press
    Keywords: Gracilaria gracilis ; Red seaweed ; Culture ; Agar ; IR spectroscopy ; Biochemical composition
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp. 2499–2512
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 2
    facet.materialart.
    Unknown
    Etude d'une population naturelle de la rhodophycée Cystoclonium purpureum. (2016)
    Details
    Publication Date: 2021-05-19
    Description: L'etude d'une population naturelle de l'algue rouge Cystoclonium purpureum a montre que les thalles debutent leur croissonce au printemps pour atteindre leur developpement maximum ent ete. En automne, les algues commencent a disparaitre progressivement. En effet, le poids maximum des thalles est atteint en Juillet (No. 40g). Pendant la meme periode, la longueur des algues atteint son maximum (25,3 cm). Quand au diametre de la fronde, son evolution au cours du temps n'est pas claire. La biomass de Cystoclonium atteint egalement son apogee en Juillet (environ 35 g de MS/m2)
    Description: Study of Cystoclonium purpureum showed that thalli begin to grow in spring and reach highest developement in summer. In autumn, these algae disappear gradually. In fact, the maximum weight is obtained in July (No.40g). In the same period, algae length reach its maximum value, too (25,3cm). While frond diameter evolution isn't clear. Biomass of Cystoclonium reach its highest value in July, too (about 35g DM/m super(2))
    Description: Published
    Keywords: Biomasse ; Rhodophycée ; Growth ; Weight ; Length ; Population dynamics ; Seaweeds ; Biomass ; Seasonal variations ; Cystoclonium purpureum ; Marine
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp. 20-36
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 3
    facet.materialart.
    Unknown
    Etude de la variabilité des spores de Gracilaria verrucosa (Hudson) Papenfuss. (2016)
    Details
    Publication Date: 2021-05-19
    Description: L'etude de la viabilite des spores de l'algue rouge Gracilaria verrucosa a montre que le taux de survie diminue de 100% a 8% pour les tetraspores et a 4% pour les carpospores apres trois semaines de culture.
    Description: Study of Gracilaria verrucosa spores growth showed that survival rate decreases from 100% to 8% for tetraspores and to 4% for carpospores after three weeks of culture
    Description: Published
    Keywords: Algue rouge ; Growth ; Variability ; Survival ; Seaweed culture ; Spores ; Gracilaria verrucosa ; Marine
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp. 54-58
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 4
    facet.materialart.
    Unknown
    La rhodophycée Gracilaria verrucosa (Hudson) Papenfuss, du lac de Bizerte (Tunisie): variations mensuelles de la biomasse, du rendement et de la qualité de l'agar. (2016)
    Details
    Publication Date: 2021-05-19
    Description: During the year of 1999, the red seaweed Gracilaria verrucosa (Hudson) Papenfuss (Rhodophyta, Gracilariales, Gracilariaceae), has been followed monthly in Bizerte lake (in the north of Tunisia). The parameters studied are: biomass, agar-yield, gel strength, gelling and melting temperatures. The results showed that the highest average of wet biomass is recorded in June (2500 g/m super(2)) and the lowest is obtained in October (130 g/m super(2)). The highest agar-yield is obtained in April (37,92 %) ; while the lowest is recorded in September (10,67 %). High and low gel strengths are obtained in May (410g /cm super(2)) and in December (125 g :cm super(2)), respectively. Gelling temperature varies between 31 degree C and 44~ 'C, while melting temperature varies between 79 degree C and 100 degree C
    Description: Published
    Keywords: Qualité ; Agar ; Yield ; Quality ; Seaweed products ; Biomass ; Gracilaria verrucosa ; Brackish
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp. 127-136
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 5
    facet.materialart.
    Unknown
    Effets de la température et de la lumière sur la croissance des tétraspores de la rhodophycée Gracilaria verrucosa (Hudson) Papenfuss. (2016)
    Details
    Publication Date: 2021-05-19
    Description: L'etude de l'influence de la temperature et de la lumiere sur la croissance des tetraspores Gracilaria verrucosa a montre que l'intensite lumineuse optimale est comprise entre 85 et 110 Kappa E/m super(2)/s a 20 degree C et entre 80 et 100 Kappa E/ m super(2)/s a 25 degree C
    Description: Study of temperature and light influence on Gacilaria verrucosa tetraspores growth showed that optimal light intensity is situated between 85 and 110 Kappa E/m super(2)/s at 2 degree C and between 80 and 100 Kappa E/m super(2)/s at 25 degree C.
    Description: Published
    Keywords: Croissance ; Tétraspores ; Rhodophycée ; Temperature effects ; Growth ; Light intensity ; Seaweeds ; Gracilaria verrucosa ; Marine
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp. 62-79
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 6
    facet.materialart.
    Unknown
    Influence of irradiance and salinity on the growth of carposporelings and juvenile tetrasporophytes in Gracilaria gracilis ( Stackhouse) M. Steentoft, L.M. Irvine & W.F. Farnham ( Rhodophyta; Rhodophyceae; Gracilariales) and agar yield. (2017)
    Details
    Publication Date: 2021-05-19
    Description: The present study aims to investigate the effects of irradiance and salinity on the growth and agar yield in early stages of development of carposporelings and young tetrasporophytes of Gracilaria gracilis in the laboratory conditions. Three levels of irradiance, photoperiod and salinity were tested. The results showed that the highest growth in basal disc of carposporelings was recorded at 8:16h light/dark, 60 μmol photons m-²s-1, and a salinity of 40 psu after four weeks of culture. The optimal percentage of erect fronds occurred at 16:8 h light/dark, 32 μmol photons.m-² s-1 and a salinity of 30 psu .The highest weight (about 6000mg) of juvenile tetrasporophytes was recorded at 40psu after 228 culture days. The maximum of length was also obtained at 40 psu at the end of the study. The best agar yield was recorded at 8:16 h light/ dark and a salinity of 20 psu. This study proved that Gracilaria may be cultivated using spores in order to obtain mature plants and then extract useful compounds such as agar.
    Description: Cette étude a été réalisée sur les carpospores et les petites plantules (tétrasporophytes juvéniles) qui en sont issues de la rhodophycée Gracilaria gracilis de la lagune de Bizerte. Elle a pour objectif de tester l’effet de trois intensités lumineuses, photopériodes et salinités sur la croissance et le rendement en agar-agar. Les résultats montrent que la croissance la plus importante des carpospores a été enregistrée sous une intensité lumineuse de 60 μ mol photons m-2s-1, une photopériode de 8 :16 h et une salinité de 40 psu (260 ± 64.48 μm) après quatre semaines de culture. Le pourcentage le plus élevé (100 %) des frondes érigées a été obtenu en fin de culture sous 32 μ mol photons m-2s- 1, une photopériode 16 : 8 h et une salinité de 30 psu. Le poids le plus élevé (environ 6000 mg) des petites plantules issues des carpospores a été enregistré après 228 jours de culture à 40 psu. La longueur maximale (16.25 ± 0.36 cm) a également été obtenue à une salinité de 40 psu. Le rendement en agar-agar a atteint 30.75 ±7.15 % du poids sec de l’algue avec les valeurs les plus faibles d’intensité lumineuse, de photopériode et de salinité. Cette étude a mis en évidence la possibilité de culture de Gracilaria à partir des spores afin d’obtenir des plantes adultes et d’en extraire par la suite des substances d’intérêt tel que l’agar-agar.
    Description: Published
    Keywords: Gracilaria gracilis ; Growth ; Carposporelings ; Tetrasporophytes ; Irradiance ; Salinity ; Agar
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp.141-150
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 7
    facet.materialart.
    Unknown
    Evaluation des potentialités quantitatives naturelles des Gracilaires (algues rouges) du lac Nord de Tunis. (2016)
    Details
    Publication Date: 2021-05-19
    Description: L’estimation de la biomasse de la macroalgue Gracilaria dans le lac nord de Tunis a été réalisée au cours de Juin-Juillet 1996 à partir de 38 stations d’échantillonnage couvrant tous les types de recouvrement de l’espèce. Il en ressort que la biomasse en poids humide est de 191 g/m2 (28 g/m2 en poids sec) et engendre un potentiel total estimé à 508 tonnes, soit 74 tonnes en poids sec (la matière sèche représentant en moyenne 14,5 % de la matière humide). Eu égard à la quantité de Gracilaria disponible à l’état naturel, la valorisation de cette espèce au niveau de ce site pourrait demander le recours à la phycoculture.
    Description: The red seaweed Gracilaria biomass in the Tunis north lake (Tunisia) was estimated between June and July 1996 with reference to different stations. This biomass represent 191 g/m super(2) (wet weight) and 28 g/m super(2) (dry weight). so the total quantity is estimated to 508 t in wet and 74 in dry (the average of dry material represent in general 14,5 % of the humid materiel). Because of its low natural total production, the development of Gracilaria seaweed in this site need culture processing.
    Description: Published
    Keywords: Macroalgues ; Phycoculture ; Potential resources ; Aquaculture development ; Marine aquaculture ; Seaweed culture ; Coastal lagoons ; Biomass ; Seaweeds ; Gracilaria ; Brackish
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: 15-27
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 8
    facet.materialart.
    Unknown
    Résultats des cultures expérimentales de la rhodophycée Gracilaria verrucosa (Hudson) Papenfuss dans le lac de Bizerte, Tunisie septentrionale. (2016)
    Details
    Publication Date: 2021-05-19
    Description: This study was conducted in Bizerte lake (Tunisia) between April and July of 1998. It concerns Gracilaria verrucosa culture with 3 techniques in order to determine the best one. After 58 days, the sand pudding method gave the best result with reference of average weight (1205 g), % of recuperation of the tuft (90 %), final density (2,7 kg/m super(2)) and specific growth rate (3,100).
    Description: Published
    Keywords: Mode de culture ; Accroisseirent du poids ; Densité de culture ; Sujet growth rate ; Density ; Experimental culture ; Seaweed culture ; Culture media ; Aquaculture techniques ; Gracilaria verrucosa ; Brackish
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp. 113-125
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 9
    facet.materialart.
    Unknown
    Potentialités en macroalgues: cartographie et biomasse de l'agarophyte Gracilaria dans le lac de Bizerte. (2016)
    Details
    Publication Date: 2021-05-19
    Description: The prospecting study of the Gracilaria in Bizerte lake (Tunisia) between the river bank and a depth of 3 m and concerning 1300ha shows that the macro seaweeds cover a surface of 348 ha and give a wet total biomass of 4775 (that is 573 t dry weight) with reference to average density of 1,7 kg/m super(2). These species are principally present as band between Menzel Abderrahman and Oued Gueniche (Tunisia)
    Description: Published
    Keywords: Macroalgues ; Fishery surveys ; Botanical resources ; Seaweed harvesting ; Biomass ; Gracilaria ; Brackish
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp. 17-34
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 10
    facet.materialart.
    Unknown
    Culture des spores de Gracilaria gracilis (Stack house) M. Stentoft), L.M. Irvine et W.F. Farnham, 2006 et G. Bursa-pastoris (Gmelin) Silva, 1952, de la lagune de Bizerte. (2015)
    Details
    Publication Date: 2021-05-19
    Description: Ce travail a porté sur la culture au laboratoire de carpospores et de tétraspores issues de deux algues rouges : Gracilaria gracilis et G. bursa-pastoris de la lagune de Bizerte. Différentes conditions d’intensité lumineuse et de photopériodes ont été testées. Les résultats ont montré que la meilleure croissance des carpospores a été enregistrée sous la photopériode de 8/16 et une intensité lumineuse de 2000 lux et ceci pour les deux espèces. Pour les tétraspores, l’optimum de croissance a eu lieu à la même photopériode mais à 3600Lux pour Gracilaria gracilis et 2000 Lux pour G. bursa-pastoris. Ces résultats montrent certaines convergences vis-à-vis de leurs exigences en lumière mais aussi certaines divergences dont on devrait en tenir compte dans le futur pour cultiver les deux espèces à une plus grande échelle.
    Description: This study has been carried out on the carpospores and tetraspores of the two seaweeds Gracilaria gracilis and G. bursa-pastoris collected in theBizerte lagoon . Both types of spores were cultivated in laboratory conditions. Different irradiation levels and light / dark cycles were tested. The results showed that the highest growth of carpospores was recorded at 8:16 light/ dark cycle and 2000 Lux. While the best growth of tetraspores was obtained at 3600 Lux in G. gracilis and 2000 Lux in G. bursa-pastoris, the two at 8:16 photoperiod. These results showed some slight similarity of the two species but in the same time some differences in irradiance requirements. These differences are very important to take into account for the future cultures in a large scale.
    Description: Published
    Keywords: Gracilaria gracilis ; Carpospores ; Culture ; Tétraspores ; G. bursa-pastoris
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed
    Format: pp.89-99
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...