Study on liquid fermentation of a strain probiotics Bacillus subtilis for aquaculture

This paper found out the liquid fermentation medium and fermentation techonlogical conditions of optimization for product of Bacillus subtilis HJ02 by orthogonal experiment,single factor experiments and a 100 L fermentation pot's pilotscale experiment.The optimum medium was glucose 10g/L,maize starch 8 g/L,soybean powder 25 g/L,MnSO4 30.8 mg/L,Mg2SO4 5 g/L,NaH2P04 0.52 g/L,Na2HP04 2.33 g/L.The optimum fermentation condition was obtained as follows: fermentation temperature 30 ℃,initial pH 7.0,the optimum vaccinal bacterium age 18 h.The cost of medium decreased beyond 50% through optimization and the bacterial concentration reached 7.19×109 cfu/mL.