植物乳杆菌XL-02发酵产γ-氨基丁酸条件的优化

Optimization of Fermentation Conditions for γ-Aminobutyric Acid Production by Lactobacillus Plantarum XL-02

为提高γ-氨基丁酸(GABA)产量,对植物乳杆菌XL-02进行发酵条件的优化。首先,采用单因素方法对底物添加量、发酵温度、发酵时间、接种量和pH值等因素进行考察,在此基础上进行4因素3水平的响应面实验优化。结果表明:在L谷氨酸钠浓度为2.0 g/L,发酵温度30℃,接种量11%和pH值6.0的条件下,发酵60 h,γ-氨基丁酸含量由原来的0.23 g/L提高到了1.14 g/L,比优化前提高了4.96倍.此条件下理论预测值1.09 g/L,验证实验测得为1.14 g/L,与预测值接近,说明预测模型可靠性较高,可应用于γ-氨基丁酸发酵条件的优化。

To improve the ability of gamma-aminobutyric acid(GABA)by Lactobacillus plantarum XL-02,L.plantarum XL-02 was optimized in this study.Firstly,using single-factor test,the effects of these 5 parameters,i.e.,the substrate addition,fermentation temperature,fermentation time,inoculation amount and intial pH of medium were studied.Then the key parameters of fermentation conditions were statistically optimized by response surface methodology with 4 factors in 3 levels.The optimal conditions were sodium hydrogen glutamate addition 2.0g/L,inoculum 11%,pH 6.0 and temperature fermentation at 30℃for 60 h.Under the conditons,the gamma-aminobutyric acid yield was 4.96 times from 0.23 g/L to 1.14 g/L.The verification test value of the gamma-aminobutyric acid 1.14 g/L,which was nearly in agreed with the theoretical prediction value 1.09 g/L.The results suggested the predicted model was reliable and available for the optimization of gamma-aminobutyric acid fermetation coditions.