采用响应曲面法对海洋酵母菌株Rhodotorula benthica OY92摇瓶发酵产γ-氨基丁酸的发酵条件进行了优化。在单次单因子试验研究的基础上,利用Plaekett-Burman(PB)设计对发酵条件中相关影响因素的效应进行评价,表明MgSO4·7H2O、NaCl和起始pH显著影响γ-氨基丁酸发酵水平;采用3因素3水平Box-Behnken试验设计优化MgSO4·7H2O、NaCl浓度和起始pH,建立发酵培养基及发酵条件的二次多项式方程,预测获得在MgSO4·7H2O 1.21 g/L,NaCl 4.79 g/L,起始pH 5.75时发酵水平最高。经实验验证,预测值与验证试验平均值接近,在此条件下,γ-氨基丁酸发酵水平由优化前7.39 g/L提高到13.89 g/L。

Response surface methodology( RSM) was employed to enhance the production of γ-amino butyric acid by marine strain Rhodotorula benthica OY92. A significant influence of MgSO4·7H2O,NaCl,and initial pH onγ-amino butyric acid production was noted with Plackett-Burman design. Then,a three-level Box-Behnken design was employed to optimize the medium composition and culture conditions for the production of the γ-amino butyric acid in shake-flask. Using this methodology,the quadratic regression model of producing γ-amino butyric acid was built and the optimal combinations of media constituents and culture conditions for maximum γ-amino butyric acid production were determined as MgSO4·7H2O 1. 21g / L,NaCl 4. 79 g / L,and initial pH 5. 75. γ-amino butyric acid production obtained experimentally was coincident with the predicted value and the model was proven to be adequate. The enhancement of γ-amino butyric acid from 7. 39 g / L to 13. 89g / L was achieved with the optimization procedure.