拮抗菌巨大芽孢杆菌L2发酵条件的响应面优化

为探明拮抗菌巨大芽孢杆菌（Bacillus megaterium）L2的发酵条件，提高其抑菌活性，以链格孢菌（Alternaria alternaria）为指示菌，以抑菌圈直径为响应值，优化其发酵条件。在单因素试验的基础上，采用响应面法对发酵条件中各因素进行优化。结果表明：最优发酵条件为牛肉膏4.6 g/L，氯化钠3.0 g/L，初始pH值为7.0，葡萄糖15 g/L，接种量6%，装液量50 mL/250 mL。在此优化条件下，抗菌物质的抑菌圈直径大小从未优化前的（14.55±0.43）mm提高至（34.99±0.14）mm，抑菌圈直径增加了140.48%。

Optimization of fermentation conditions of antagonistic bacterium Bacillus megaterium L2 by response surface methodology

In order to investigate the fermentation conditions of antagonistic bacterium Bacillus megaterium L2 and improve the bacteriostatic activity, using Alternaria alternaria as indicator bacterium and the diameter of the inhibition zone as the response value, the fermentation conditions were optimized. On the basis of single factor experiments, the factors affecting the fermentation conditions were optimized by response surface methodology. The results showed that the optimal fermentation conditions were as follows: beef extract 4.6 g/L, sodium chloride 3.0 g/L, initial pH value 7.0, glucose 15 g/L, inoculum 6% and loading volume 50 ml/250 ml. Under the optimized conditions, the inhibition zone diameter of antimicrobial substances increased from (14.55±0.43) mm to (34.99±0.14) mm, which increased 140.48%.