产脂肪酶黑曲霉摇瓶发酵条件优化研究

The Optimization of Flask Fermentation Conditions for the Production of Extracellular Lipase from Aspergillus niger

黑曲霉Aspergillus niger G62s是一株具有遗传稳定的高产脂肪酶菌株。针对于G62s摇瓶发酵条件进行统计学优化研究,以提高该菌株的产脂肪酶能力。首先,采用单因素方法对发酵接种量、摇瓶装量、培养温度、培养时间等因素进行考查,在此基础上进行4因素3水平的响应面分析(Response surface methodology,RSM)的统计学优化。得到的优化发酵条件是接种量1.9%,摇瓶装量56 m L(500 m L摇瓶),培养温度30 oC,培养时间75 h。在该优化条件下,脂肪酶活性达到(212 9±39.9)U/m L,相比初始的发酵条件提高16.7%。针对于影响G62s菌株产脂肪酶的4个发酵条件,在单因素实验的基础上通过RSM方法优化,显著提高了目标菌株脂肪酶产量。

Aspergillus niger G62 s is a genetically stable strain of producing high-yield lipase. This work is to have statistic optimization for the flask fermentation conditions of G62 s aiming at increasing the capacity of strain yielding lipase. Firstly, using single-factor test, the effects of these 4 parameters, i.e., the inoculation amount, working volume, culture temperature and culture time, on the lipase yield were studied. Then the key parameters of fermentation conditions were statistically optimized through the response surface methodology（RSM）with 4 factors in 3 levels. The optimal conditions were 1.9% inoculum size in 56 m L working volume（in 500 m L flasks）at 30 oC for 75 h. Using these conditions, the activity of lipase reached 212 9±39.9 U/m L, increased 16.7% comparing to that of the initial fermentation conditions. In conclusion, based on the single-factor test of 4 fermentation factors affecting the lipase yield of G62 s, optimization by RSM significantly increased the yield of the target strain.