Study on liquid fermentation conditions of Bacillus amyloliquefaciens TF28

Bacillus amyloliquefaciens TF28, an endophytic bacterium isolated from soybean root,showed strong antifungal activity in vitro. In order to improve the fermentation capacity of the strain, the optimum medium and conditions for its liquid fermentation were optimized by using single factor and orthogonal experiments. The results showed that the optimum medium was as follows: glucose 1%,Beef extract 0.5%, Yeast extract 0.3%, MnSO40.01%, and CaCO330.5%. The favourable fermatation conditions was determined: initial pH 7.5, temperature 30 ℃, fermentation cycle: 36 h, pack amount50 mL/250 mL triangle bottle, and rotation speed 200 r· min-1.