枯草芽孢杆菌产碱性果胶酶发酵条件的优化

Optimization of Fermentation Medium for Alkaline Pectinase of Bacillus Subtilis

通过单因素实验对枯草芽孢杆菌菌株发酵产碱性果胶酶的培养基组分及培养条件进行优化。利用单因素实验确定了产酶的最优培养基:30 g/L豆饼粉、35 g/L马铃薯淀粉、20 g/L果胶、2.775 g/L氯化钙、4.025 g/L硫酸锌、113.6 g/L Na 2HPO 4。同时对温度、接种量、发酵pH进行优化,得到最优发酵条件:温度35℃、接种量3%、发酵过程控制pH=7.4,在此基础上进行补料流加实验,补料配方为350 g/L葡萄糖、10 g/L果胶,补料控制总糖浓度为20 ug/mL,并调整转速和风量控制溶氧30%~40%,最终酶活达到6120 U/mL,较初始酶活1061 U/mL提高了4.77倍。

The medium components and culturing conditions for bacillus subtilis were optimized by single factor test to increase the production of alkaline pectinase.The results showed that the optimized medium consisted of 30 g/L soybean powder,35 g/L potato starch,20 g/L pectin,2.775 g/L CaCl,4.025 g/L ZnSO,113.6 g/L Na 2HPO 4 and the optimized culture conditions were as follows:35℃,inoculation amount of 3%,and pH=7.4 in fermentation process.On this basis,feeding experiments were carried out.The feeding formula was 350 g/L glucose,10 g/L pectin,the total sugar concentration was controlled by 20μg/mL,and the dissolved oxygen was controlled by 30%~40%by adjusting the speed and air flow.The final enzyme activity reached 6120 U/mL,which was 477%higher than the initial enzyme activity of 1061 U/mL.