利用枯草芽孢杆菌生产中温淀粉酶发酵条件的优化研究

Study on the Optimized Fermentation Condition for the Production of Midrange Thermal Stable Amylase by Bacillus Subtilis

为了进一步研究枯草芽孢杆菌发酵产中温淀粉酶的工艺条件,在前期经过菌种筛选及诱变育种得到一株高产中温淀粉酶的枯草芽孢杆菌,并通过摇瓶发酵实验初步确定了在影响该菌株发酵产酶的主要营养因素及环境条件的基础上,以枯草芽孢杆菌为发酵菌,通过三因素三水平正交实验法对枯草芽孢杆菌的5L发酵罐发酵产酶条件进行优化。实验结果表明:枯草芽孢杆菌产中温淀粉酶的最优发酵条件为:接种量10%、初始发酵pH值为6、玉米粉与豆饼粉之比为3.5∶1、培养温度37℃,接种种龄20h、转速为450r/min、通风量为1vvm和发酵时间65h。经过三批发酵实验验证,最优条件下中温淀粉酶最高酶活达到6907U/mL。

This article discusses the technological conditions for the production of midrange thermal stable amylase by bacillus subtilis.With the initial bacteria＆#39;s separation and mutation breeding,a high-yielding bacillus subtilis is cultivated.The preliminary shake flask fermentation figures out the main affecting nutritional factors and environmental conditions. With bacillus subtilis as the zymophyte,three-factor-and-three-level orthogonal test is conducted.The final result points out the optimal fermentation as the following：10% inoculums size,the initial fermentation pH value is 6,the ration of corn flour and bean cake powder is 3.5∶1,culture temperature is 37 ℃,inoculation period is 20 h,rotating speed 450 r/min,ventilation quantity is 1 vvm,and the fermentation period is 65 h. Three series of fermentations indicate that the highest enzyme activity of Midrange Thermal Stable Amylase can reach 6907 U/mL.