枯草芽胞杆菌B201产芽孢培养基优化

采用单因素试验及正交试验设计对枯草芽胞杆菌Bacillus subtilis B201产孢培养基进行了碳源、氮源、无机盐筛选及优化，最终确定B201发酵培养基配方为玉米粉3 g/L，糖蜜10 g/L，豆粕粉10 g/L，鱼粉10 g/L，K₂HPO₄ 2 g/L，Na₂HPO₄ 2 g/L，MgSO₄ 0.5 g/L，MnSO₄ 0.5 g/L。优化后的培养基在500 L通气式机械搅拌发酵罐中进行了小试，结果表明B201生长快速，发酵16 h开始形成芽孢，26 h放罐后发酵液活菌量达到1.06×1010 CFU/mL，芽孢量8.8×109 CFU/mL，芽孢形成率为83.0%，活菌含量和芽孢形成率较高，为B201工业化生产奠定了基础。

Optimization of Sporulation Medium of Bacillus subtilis B201

The carbon source, nitrogen source and inorganic salt of Bacillus subtilis B201 sporulation medium were screened and optimized by single factor experiment and orthogonal experimental design. Ultimately the fermentation culture medium of B201 were composed of 3 g/L corn flour, 10 g/L molasses, 10 g/L soybean powder, 10 g/L fish meal, 2 g/L K₂HPO₄, 2 g/L Na₂HPO₄, 0.5 g/L MgSO₄, 0.5 g/L MnSO₄. Then a small-scale test for the optimal culture medium was experimented in 500 L mechanical ventilation stirring fermentor. The results showed that B201 grew rapidly and spores formed after 16 h. The fermentation was completed after 26 h and the amount of live bacteria in fermentation liquid reached 1.06×1010 CFU/mL and 8.8×109 CFU/mL for spores, so the forming rate of spore was 83.0%. High numbers of bacteria and spores fermented by using this optimized fermentation medium provide useful information for the industrial production of B201.