短小芽孢杆菌HR10产孢培养基及发酵条件优化

Optimization of Sporulation Medium and Fermentation Conditions for Bacillus pumilus HR10

短小芽孢杆菌(Bacillus pumilus)HR10是一株具有促生抗逆作用的优良菌株。探究菌株HR10产孢的最佳发酵培养条件,对于在更大规模上进行生产发酵具有重要的指导意义。以稀释涂布平板法计数活菌数和芽孢数并计算芽孢率;对菌株HR10产孢培养基的碳源、氮源和无机盐进行单因素分析及正交试验,并采用摇瓶发酵法对影响菌株HR10产孢的几种发酵因子进行单因素优化。结果显示,菌株HR10的产孢培养基最佳组成成分为葡萄糖1%、糖蜜1%、豆饼粉2%、KCl 0.3%、MnSO40.4%。最佳发酵条件为温度37℃、pH 7、250 mL三角瓶装液量50%、接种量5%、转速220r/min、培养时间52 h。芽孢数达到2.37×10^(10)cfu/mL,芽孢率达94.46%。相比初始培养基芽孢数提高了60.77倍,为其工业化生产提供参考。

Bacillus pumilus HR10 is an excellent strain with growth-promotion and anti-adversity effect.Exploring the optimal fermentation and culturing conditions for sporulation of HR10 strain has an important guiding significance for the production and fermentation on a larger scale.The number of bacterial cells and gemmae were counted by diluted spreading plate method and calculated the gemma rate.Carbon source,nitrogen source and inorganic salt for HR10 strain sporulation medium were analyzed by single factor and orthogonal test,and the single-factor optimization of several fermentation factors affecting HR10 strain sporulation was carried out by shake flask fermentation.The results showed that the best components of the sporulation medium of strain HR10 were:glucose 1%,molasses 1%,soybean cake powder 2%,KCl 0.3%,MnSO40.4%.The optimal fermentation conditions were:37℃,pH 7,250 mL flask filled 50%volume with liquid,inoculation volume 5%,rotation speed 220 r/min,cultured for 52 h.The number of gemmae can reach 2.37×10^(10)cfu/mL,and the gemma rate can reach 94.46%.As compared with initial medium,the number of gemmae increased by 60.77 times,and laid a foundation for its industrialized production.