Course manual: National training on cage culture of seabass, 14 - 23 December 2009

Aquaculture aims at producing aquatic organisms of nutritional, ornamental, therapeutic and industrial value. Cage culture is one avenue where immense scope is there for all these. Cage culture is impressive to adopt in the fact that it provides ownership in public water with less cost of construction and reduced capital investment, safety from predators and competitors and ultimately high yield of fish with good economic returns

Isolation and characteriation of extreme halophiles Halomonas aquamarina and Halomonas marina from trigger fish, Abalistes stellaris (Bloch & Schneider, 1801)

Screening of bacteria from the skin, gills and gut of the marine triggerfish, Abalistes stellaris (Bloch & Schneider, 1801), collected from Vizhinjam, Kerala, India, led to the isolation of 8 halophilic bacterial strains. The isolates were able to grow optimally in culture media with 5-15% salt content. Of these, 3 extremely halophilic bacterial isolates that grew in 20-25% of salt were selected for genotypic characterisation. Bacterial strain, IJ1, isolated from skin, and strains, IJ5 and IJ6, isolated from gut of A. stellaris grew optimally at pH 7.0 and 5-15% NaCl at 35 °C. The cells were Gram negative short rods. According to the phenotypic characteristics and comparative partial 16SrRNA sequence analysis, the strain IJ1 was identified as Halomonas marina strain DSM 4741 (GenBank Accession Number: KC599209) and strains IJ5 and IJ6 as Halomonas aquamarina (GenBank Accession Numbers: KC620376 and KC599210 respectively). H. aquamarina has been reported for the first time from any environment in India and both the strains have been deposited in the microbial repository of National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau, India

Survey on functionally diverse bacterial strains from marine finfishes and crustaceans

Prokaryotic microorganisms compromise a large portion of the organic biomass of the world’s ocean and play an important role in the biogeochemical cycles and food webs of this ecosystem. Surface colonization by microorganisms is ubiquitous in marine systems with a large proportion of microbes occurring as complex communities. Despite their importance, comparatively little is known about the phylogenetic composition of this complex microbial population and the functional roles of their members. Living surfaces are ideal to explore colonization by microorganisms because eukaryotes are subject to a constant bombardment from the millions of microbial cells typically found in a millilitre of seawater

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Not AvailableIn the present study, screening of bacteria from gut of Indian oil sardine Sardinella longiceps collected from Kanyakumari coast, Tamil Nadu, India, has led to the isolation of a yellow pigmented strain SR-G1. Cell morphology, motility and the occurrence of spores were examined by phase contrast microscopy. The isolate was Gram-positive, with irregular rods, nonmotile branched cocci with colonies on nutrient agar yellow, opaque, glistening, circular and low convex with entire margin. The pH of the medium and incubation temperature were found to be limiting factors in growth of the bacterial strain. The optimum temperature for growth was 28 degree celsius. Key biochemical reactions include positive for catalase and negative for oxidase. The strain was H 2S-producing, starch and gelatinhydrolyzing and alkali-tolerant. The isolate grew well in minimal media containing glucose, fructose and sucrose. The strain SR-G1 was identified as Microbacterium esteraromaticum based on the phenotypic characteristics and 16S rRNA sequence analysis. Extraction and separation of the bacterial carotenoid was carried out by a one step methanol of hexane extraction. The coloured supernatant in hexane solvent was analyzed by using UV- Visible Spectrophotometer from 350-550 nm range for detecting the lambda max . The bacterial pigment was identified using a combination of UV/visible spectral data and HPLC retention time as Neoxanthin. Neoxanthin is one of the major xanthophylls which are reported to be directly associated with reduction in the risk of cancers, cardiovascular disease, agerelated macular degeneration, and cataract formation. Hence, the potential of microbial producers as an alternative to chemical synthesis of xanthophylls could be further examined.Not Availabl

Occurrence of fluorescent bacterium Pseudomonas aeruginosa a putative biocontrol agent in Indian pompano Trachinotus mookalee Cuvier, 1832

Bacterial diversity studies in healthy marine finfish Trachinotus mookalee Cuvier, 1832 have lead to the isolation of six strains of Pseudomonas spp. The bacteria were isolated from the skin, gills and intestine of live and healthy fish collected from Karwar, Karnataka, India (N- 13°, 05.722‘; E- 079°, 48.658‘). Among the strains three were non-fluorescent and others were fluorescent Pseudomonas strains. Fluorescent strains are known to secrete pyoverdine, a yellow-green siderophore which has wide application in agriculture and allied sectors. Fluorescent strains were further characterized by 16S rDNA sequencing and were identified as Pseudomonas aeruginosa strain TRG1 (Genbank Accession No. KC109784)

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Not AvailableScreening of bacteria from the skin, gills and gut of the marine triggerfish, Abalistes stellaris (Bloch & Schneider, 1801), collected from Vizhinjam, Kerala, India, led to the isolation of 8 halophilic bacterial strains. The isolates were able to grow optimally in culture media with 5-15% salt content. Of these, 3 extremely halophilic bacterial isolates that grew in 20-25% of salt were selected for genotypic characterisation. Bacterial strain, IJ1, isolated from skin, and strains, IJ5 and IJ6, isolated from gut of A. stellaris grew optimally at pH 7.0 and 5-15% NaCl at 35 °C. The cells were Gram negative short rods. According to the phenotypic characteristics and comparative partial 16SrRNA sequence analysis, the strain IJ1 was identified as Halomonas marina strain DSM 4741 (GenBank Accession Number: KC599209) and strains IJ5 and IJ6 as Halomonas aquamarina (GenBank Accession Numbers: KC620376 and KC599210 respectively). H. aquamarina has been reported for the first time from any environment in India and both the strains have been deposited in the microbial repository of National Bureau of Agriculturally Important Microorganisms (NBAIM), Mau, India.Not Availabl

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Not AvailableProkaryotic microorganisms compromise a large portion of the organic biomass of the world’s ocean and play an important role in the biogeochemical cycles and food webs of this ecosystem. Surface colonization by microorganisms is ubiquitous in marine systems with a large proportion of microbes occurring as complex communities. Despite their importance, comparatively little is known about the phylogenetic composition of this complex microbial population and the functional roles of their members. Living surfaces are ideal to explore colonization by microorganisms because eukaryotes are subject to a constant bombardment from the millions of microbial cells typically found in a millilitre of seawater.Not Availabl

Not Available

Not AvailableProkaryotic microorganisms compromise a large portion of the organic biomass of the world’s ocean and play an important role in the biogeochemical cycles and food webs of this ecosystem. Surface colonization by microorganisms is ubiquitous in marine systems with a large proportion of microbes occurring as complex communities. Despite their importance, comparatively little is known about the phylogenetic composition of this complex microbial population and the functional roles of their members. Living surfaces are ideal to explore colonization by microorganisms because eukaryotes are subject to a constant bombardment from the millions of microbial cells typically found in a millilitre of seawater.Not Availabl