【摘要】 为提高对烟草黑胫病具有良好防治效果的贝莱斯芽胞杆菌Bacillus velezensis YC11菌株的芽胞产生水平，通过Plackett-Burman试验筛选出影响YC11摇瓶发酵芽胞产量的3个显著因子：玉米粉、酵母粉和硫酸镁；再结合最陡爬坡试验、Box-Behnken(BB)响应面法拟合显著因子与芽胞产量的非线性方程求解，得到优化的YC11菌株发酵产胞培养基配方。结果表明，优化后的最佳配方为玉米粉13.74 g/L、鱼粉15.00 g/L、酵母粉15.73 g/L、玉米浆5.00 g/L、硫酸镁0.59 g/L和磷酸二氢钾0.30 g/L，此时模型预测发酵液芽胞最佳产量为114.4亿芽胞/m L，验证值为116.6亿芽胞/m L，预测值与验证值之间吻合较好，较优化前芽胞产量（70.8亿芽胞/m L）提高了64.7%。采用500 L发酵罐进行发酵验证，菌株YC11的芽胞产量为150亿芽胞/m L。盆栽试验结果表明，菌株YC11发酵液对烟草黑胫病的防效可达到100%。更多还原

【Abstract】 The study aimed to increase the spore production by Bacillus velezensis strain YC11 which showed good control effects on black shank of tobacco. Three media components, including corn flour, yeast powder and magnesium sulphate, which significantly influenced the spore production by YC11, were screened out through Plackett-Burman design. A nonlinear equation was fit by the interaction between the most significant factors and the spore production through the steepest ascend experiment and Box-Behnken design. An optimized medium was obtained for the spore production, of which the composition was as the followings: corn flour 13.74 g/L, fish meal 15.00 g/L, yeast powder 15.73 g/L, corn steep liquor 5.00 g/L, magnesium sulphate 0.59 g/L, and potassium dihydrophosphate 0.30g/L. The theoretical spore production of this nonlinear model was 1.144×10¹⁰ spores/mL,which was very close to the practical spore production with the optimized medium in shake-flask fermentation.After optimization, the spore production was increased by 64.7%. The spore production of strain YC11 with the optimized medium in 500L fermenter reached 1.50×10¹⁰ spores/mL.The results of indoor pot experiment showed that the average control effect of fermentation broth of strain YC11 on tobacco black shank could reach 100%.更多还原