Abstract
Purple Non Sulfur Bacteria (PNSB) are widely distributed in various aquatic environments like oceans, lakes and rivers in high temperature, low temperature, low salt, and high salt environment. They grow in both microaerobic and anaerobic light conditions while utilizing various substrates as sources of carbon and energy with ammonium and/ or nitrate as a source of nitrogen and may also use sulfide or thiosulfate as an electron donor under photosynthetic condition. They are metabolically most versatile among all prokaryotes. Phototrophic bacteria for waste water treatment have generally proven to be cost effective system because PNSB does not only produce quality effuent, but produces substances of commercial interest, such as, single cell protein (SCP), biopolymers, antimicrobial agents therapeutic compounds, etc.
In the present study mixed population of PNSB have been isolated from East Kolkata Wetland and selected on the basis of their protein and carbohydrate content. The ability of the mixed population has been explored for the production of experimental fish feed and the potential of this feed was compared with the commercially available fish feed on four different types of ornamental fishes. Survivality and growth of these types of fishes were compared using both types of feed.
