响应面法优化黄杆菌突变株产脂肪酶摇瓶发酵条件

Optimization of lipase production conditions by Flavobacterium sp.YY25-H0.5 using response surface methodology

应用响应面法对经超临界CO2诱变获得的黄杆菌突变株(Flavobacterium sp.YY25-H0.5)产脂肪酶的摇瓶发酵条件进行优化.首先应用Plackett-Burman设计对影响产酶的因素进行效应评价,筛选出3个主要影响因素:起始pH,橄榄油含量和Triton X-100含量.然后用响应面法对主要因素进行优化,得出最适条件:起始pH6.90,橄榄油含量1.17%和Triton X-100含量0.33%.YY25-H0.5在优化条件下摇瓶发酵24 h所产脂肪酶为38.9 U/mL,是优化前的1.34倍.该突变株的产酶活力在产脂肪酶的细菌中居较高水平.

Flavobacterium sp. YY25-H0.5 was a mutant strain obtained from supercritical CO2 treatment. Here the fermentation conditions of lipase production by YY25-H0.5 were optimized using response surface methodology. Firstly, Plackett-Burman design was used to evaluate the influence factors related to lipase production and three statistically significant factors （i. e. pH, olive oil content and Triton X-100 content） were screened out. Then, the optimal combined conditions for maximum enzyme activity were further optimized by response surface methodology and were determined as follows： pH 6.90, olive oil 1. 17%, Triton X-100 0.33%. Under the optimal conditions, the lipase activity of YY25-H0. 5 was improved to 38.9 U/mL by 24 h of fermentation, indicating a higher level of enzyme yield in lipase production by bacterium.