细链格孢菌拮抗细菌枯草芽孢杆菌XL12菌株发酵产抗菌蛋白条件研究

为了提高细链格孢菌[Alternaria alternate（Fr）Keissler]拮抗细菌枯草芽孢杆菌（Bacillus subtilis）XL12菌株的发酵产抗菌蛋白量,采用单因素法对XL12菌株的培养条件进行了优化,最终确定XL12最适宜的发酵条件为：基础培养基碳源和氮源（摩尔比）的比例为30∶1,接种量为0.5%,配制后灭菌前,培养液的pH调节在6.95~7.05,发酵温度为30~35℃,220 r.min-1摇床振荡培养72 h,用70%硫酸铵对XL12菌株发酵液上清液进行盐析,可以沉淀最多的抗菌蛋白。

Fermentation Conditions of Antagonistic Strain XL12 against Alternaria alternate

In order to increase the quantity of antifungal protein from Bacillus subtilis XL12, the strain was cul tured under different conditions. The optimization of fermentation factors, such as the C/N proportion of basic medium,inoculation amount, initial pH, fermentation temperature and fermentation time, was made by single factor experiments. The result showed that the optimal fermentation condition was initial pH 6. 95-7.05 and shaking flask in 220 r.min^-1 speed,fermentation temperature was 30-35℃ for 72 hours, premise of which the C/N ration is 30： 1,inoculation amount is 0.5 %, under the conditions, the most quantity of antifungai protein was obtained by the 70%（NH4）2 SO4 salting out supernatant fluid of strain XL12 fermentation.