Galactomyces geotrichum Y25产脂肪酶条件的优化

应用响应面法对Galactomyces geotrichumY25液体发酵产脂肪酶的条件进行了优化。首先采用Plackett-Burman设计对影响产酶因素的效应进行评价,筛选出黄豆粉、玉米浆和发酵时间3个对产酶影响显著的因素。用最陡爬坡路径逼近最大产酶区域后,利用响应面设计对显著因素进行优化,得出黄豆粉、玉米浆最佳质量分数分别为2.51%、2.12%,最佳发酵时间101.95 h。优化后液体发酵液中脂肪酶活力提高到34.65 U/mL,比初始酶活力9.6 U/mL提高了3.61倍。表明响应面法可显著优化Galactomyces geotrichumY25液体发酵产脂肪酶条件。

Optimization of lipase production conditions by Galactomyces geotrichum Y25

The fermentation conditions of lipase production by Galactomyces geotrichum Y25 were optimized with response surface methodology.Initially,screening design by Plackett-Burman method was used to evaluate the effects of eleven factors related to lipase production and three statistically significant factors(i.e.,soybean flour,corn steep liquor and culture time) were selected.The path of steepest ascent was used to approach the optimal region of lipase production subsequently.Then,the optimal combined conditions for maximum enzyme activity were further optimized by response surface methodology and were determined as follows : soybean flour 2.51%,corn steep liquor 2.12%,and culture time 101.95 h.Under the optimal conditions,the enzyme activity improved from 9.6 U/mL to 34.65 U/mL,a 3.61-fold increase,which indicated that the response surface methodology was an effective method for optimization of lipase production conditions of Galactomyces geotrichum Y25.