生防菌菌株A的摇瓶培养条件及发酵工艺

Studies on the Culture Condition and Fermentation Crafts of A Strain of Bacillus subtilis

[目的]优化生防菌菌株A的培养条件与液体发酵工艺。[方法]采用均匀试验设计方法、回归分析方法和分批补料发酵工艺,研究生防菌菌株A的培养条件与液体发酵工艺的优化。[结果]结果表明,适合菌株A摇瓶培养的最佳条件为:培养温度35℃,摇瓶装量12%,接种量3.0%,初始pH值7.2。20 L发酵罐分批补料发酵参数为:种子培养基为YDC培养基,培养时间24 h,接种量3.0%;发酵培养基:葡萄糖1.0%,酵母膏1.0%,CaCO31.0%,pH值7.2;流加培养基:葡萄糖1.5%,酵母膏0.5%,制成混合液一起流加,发酵8 h开始流加;发酵周期(34±2)h,在以上发酵条件下,发酵液芽孢浓度达(3.410±0.151)×109cfu/m l。[结论]该试验条件下所获得发酵液芽孢数浓度较高,可用于进一步制备生防菌剂。

[ Objective ] The purpose was to optimize the culture conditions and fermentation crafts of strain A, a kind of Bacillus subtilis （ CGMCC No. 1982）, and in order to obtain high spores concentration of fermentation broth and establish scientific foundation for empoldering the strain A. [ Method] Uniform design tests, regression analysis method and fed-batch fermentation techniques were used. [ Result] The results showed that the optimum conditions for shaking flask culture of strain A were as follows ： 35 ℃ of culture temperature, culture broth quantity 12%, inoculation amount 3.0% , initial pH value 7.2. The fed-batch fermentation crafts were ascertained by 20 L fermenter. The seed was prepared by using YDC as seed culture medium （glucose 20 g, yeast extracts 10 g, CaCO3 20 g and water 1 000 ml）, culture time 24 h and inoculation amount 3.0%. The fermentation medium （glucose 1.0% , yeast extracts 1.0%, CaCO3 1.0% and pH value 7.2） and the feeding medium, a mixture of glucose 1.5% and yeast extracts 0.5% , were confirmed. The feeding began at 8 h later and the fermenting period lasted for（34 ± 2） h, the spore concentration could reach to （3. 410 ± 0. 151 ） × 10^9 cfu/ml. [ Conclusion] The culture conditions and fermentation crafts of strain A to produce high concentration of spores was validated, which will establish scientific foundation for empoldering the strain A.