响应面法优化酿酒酵母产油脂条件

Response Surface Methodology to Optimize Lipid Production Conditions by Saccharomyces cerevisiae

摘要:

运用响应面法对酿酒酵母(Saccharomyces cerevisiae)产油脂以及发酵条件优化进行了研究。首先根据单因素实验结果, 利用Plackett-Burman设计对影响其产油脂相关因素进行评估并筛选出具有显著效应的3个因素: 柠檬酸, CaCl2和初始pH值。接着用最陡爬坡试验逼近以上3个因子的最大响应区域后, 采用Box-Behnken设计以及响应面分析法, 确定其优化后发酵条件为(w/v): 葡萄糖15%, 蛋白胨0.2%, 酵母浸粉0.4%, 柠檬酸0.471%, MgSO4?7H2O 0.1%, ZnSO4?7H2O 0.2%, CaCl2 0.025%, FeSO4?7H2O 0.005%, 初始pH值为6.74, 180 r/min, 30?C培养96 h。优化后的油脂产率(干重)达到14.55%, 比在种子培养基中油脂产率4.76%提高了3倍左右。

Abstract:

Response surface methodology (RSM) was employed to optimize culture medium for lipid production of Saccharomyces cerevisiae. Firstly, according to the results of mono-factors experiment, a Plackett-Burman design was used to investigate the effects of different factors in the ferment medium, three statistically significant factors are:citric acid, CaCl2, initial pH value, and then steepest ascent procedures was employed to define optimal response region for these three factors. Finally, Box-Behnken was employed to design. The results of experiments was analyzed by RSM with Minitab15.0 soft. The optimal lipid production medium is: glucose 15%, peptone 0.2%, yeast extraction 0.4%, citric acid 0.471%, MgSO4?7H2O 0.1%, ZnSO4?7H2O 0.2%, CaCl2 0.025%, FeSO4?7H2O 0.005%, initial pH value 6.74, 180 r/min, incubme in 30?C for 96 h. Lipid production (dry weight) after optimization is increased from 4.76% to 14.55%. The yield of lipid is increased by about 3 times.