THE APPLICATION OF PROBIOTICS IN AQUACULTURE

To expatiate current situation and prospect in applied research about  Rhodobacter sphaeroies and nitrobacteria in aquatic rearing; such as classification, morphological structure, trophic component, metabolic mechanism were briefly presented and degradation of organophosphate pesticides, aquaculture wastewater treatment, algae phase regulation, heavy metal disposal and fermentation feed, bio-reactor of the strain were also mainly discussed in this paper. Results showed that add R.sphaeroides (5×10⁷ CFU·mL^-1) to 20 mg·L^-1 ~30 mg·L^-1 dichlorvos (DDVP) exposed could reduce the mortality of zebrafish and C.auratus significantly, respectively at 96h; There were no toxic degradation products in degradation process. R.sphaeroides can be synthesized and metabolized with photosynthesis by hydrogen donor and carbon source of some different organic compounds as organic acids, alcohols and others, thus decomposed and removed organic matters, ammonia, COD, phosphorus and other nutrients high-efficiently under the light aerobic condition, dark anaerobic condition or micro-aerobic condition. On one hand, its metabolites SOD activity of the enzyme could clear the substance of malondialdehyde (MDA) which caused the algae senescence; the other hand, another product of 5-aminolevulinic (ALA) could promote the algae healthy balance growth through improved photosynthetic. We also found its remarkable effect that reduce the iron, manganese, copper, cadmium and other heavy metals content in ponds. Furthermore, the research in carotenoids, coenzyme Q, B vitamins, single cell protein (SCP) extraction to use for aquaculture feed and to be a regular, low cost, effective autonomous culture of R.sphaeroides by the form of fermentation bio-reactor was relatively much less. We also did a lot of research to improve the nitrification by strains filtrate efficiently, optimization of fermentation medium, improvement of fermentation process, optimization of strains carrier and others. Result showed that the nitrite concentration of shrimp ponds can be reduced from 1.1mg/L to 0.1mg/L within 72h by adding 1ppm

Nitrobacteria, it would be wildly used in aquatic rearing market in future.