嗜酸乳杆菌产胞壁蛋白酶的培养及发酵条件优化

Optimization of Culture Conditions and Fermentation Conditions for Cell Wall Proteinase(CEP) Production by Lactobacillus acidophilus

为优化嗜酸乳杆菌产胞壁蛋白酶的培养条件及发酵条件,分别做正交试验、单因素试验、响应面分析法。通过正交试验得出最优培养条件是:含2%葡萄糖和1%牛肉蛋白胨的MRS改良培养基。通过单因素试验和响应面分析法对嗜酸乳杆菌产胞壁蛋白酶的发酵条件进行研究,考察了培养基的初始pH值、发酵温度及发酵时间对胞壁蛋白酶比活产生的影响,确定发酵产酶的最佳条件是:初始pH 8.0、发酵温度37℃、发酵时间20 h。验证试验结果表明响应面分析法对优化产酶条件是可行的。

The suitable culture conditions and the liquid fermentation conditions of Lactobacillus acidophilus in MRS medium were optimized for producing cell wall proteinase（CEP） through orthogonal tests and single-factor test, response surface methodology. Suitable conditions to obtain cell wall proteinase（CEP） from Lactobacillus acidophilus were optimized through orthogonal tests of carbon source and nitrogen source. The optimal conditions were as following： 2% glucose and 1% beef peptone. The effects of original pH of MRS medium, fermentation temperature and time on cell wall proteinase（CEP） specific activity were studied by single-factor test and response surface methodology. The highest cell wall proteinase（CEP） specific activity was media with the original pH value of 8.0, fermentation temperature of 37 ℃ and fermentation time of 20 h. Also, the test was proved to be feasible for condition optimization of cell wall proteinase（CEP） production.