球孢白僵菌催化苯甲酸合成对羟基苯甲酸的培养条件优化研究

Optimization of culture conditions for synthesis of p-hydroxybenzoic acid from benzoic acid catalyzed by Beauveria bassiana

为了提高球孢白僵菌固态发酵产对羟基苯甲酸的能力,本研究确定了最适的苯甲酸添加量、球孢白僵菌接种量和发酵基质的种类,随后对培养基含水量、发酵pH和发酵温度进行单因素分析,在此基础上采用响应面法对上述发酵条件进行分析优化并验证。结果显示:苯甲酸初始添加量为10.11 g/kg、球孢白僵菌接种量为10%、培养基基质为麸皮30 g/kg、基质含水量为60%、发酵pH为7.75以及发酵温度为27℃时,对羟基苯甲酸产量可达(9.12±0.29) g/kg,较优化前产量5.16 g/kg提升76.74%,产率可达90.21%,较优化前51.04%提升39.17%。本研究为微生物合成对羟基苯甲酸,提供了技术参考。

In order to improve the solid-state fermentation ability of Beauveria bassiana to produce p-hydroxybenzoic acid,the addition amount of benzoic acid,the inoculation volume of Beauveria bassiana and the fermentation culture medium matrix were analyzed and optimized.The single factor analysis was carried out on the water content of the culture medium,fermentation pH and fermentation temperature.On this basis,the above fermentation conditions were comprehensively analyzed,optimized and verified by the response surface methodology.The results showed that the optimal fermentation conditions were as follows:the initial addition amount of benzoic acid was 10.11 g/kg,the inoculation amount of Beauveria bassiana was 10%,the culture medium matrix was rice bran 30 g/kg,the matrix water content was 60%,the fermentation pH was 7.75,and the fermentation temperature was 27℃,the volume of p-hydroxybenzoic acid was improved to reach(9.12±0.29)g/kg,which was 76.74%higher than that of 5.16 g/kg before optimization.The yield rate of p-hydroxybenzoic acid could reach 90.21%,39.17%higher than that of 51.04%before optimization.This study provides a technical reference for microbial synthesis of p-hydroxybenzoic acid.