通过发酵优化提高大肠杆菌生产L-半胱氨酸产量  

Enhancement of L-cysteine production in Escherichia coli through fermentation optimization

作　　者：张博 史永吉 杨辉 吴梓丹 陈开 蔡雪 柳志强 郑裕国 ZHANG Bo;SHI Yongji;YANG Hui;WU Zidan;CHEN Kai;CAI Xue;LIU Zhiqiang;ZHENG Yuguo(College of Biotechnology and Bioengineering,Zhejiang University of Technology,Hangzhou 310023,China)

机构地区：[1]浙江工业大学生物工程学院,浙江杭州310023

出　　处：《食品与发酵工业》2021年第18期175-180,共6页Food and Fermentation Industries

基　　金：国家重点基础研究发展计划(973计划)(2018YFA0901400);国家自然科学基金(32070099;31971342)。

摘　　要：该研究为提高菌株L-半胱氨酸合成能力,首先在摇瓶发酵中利用响应面分析方法对培养基组分进行了优化;其次,结合甜菜碱、氨基酸等物质的添加,在2 L发酵罐中进行了发酵放大优化。实验确定了较优的培养基成分,为葡萄糖(42.69 g/L)、硫酸铵(7.77 g/L)、酵母粉(6.53 g/L)、硫代硫酸钠(6.22 g/L);优化后L-半胱氨酸的产量显著提升,摇瓶发酵达到3.85 g/L,较优化前提高了169%。2 L发酵罐放大试验结果表明,结合外源物质添加,发酵47 h后L-半胱氨酸产量可达10.25 g/L。以上结果为后续L-半胱氨酸的工业化发酵生产奠定了基础。Cysteine is an important amino acid with active sulfhydryl group,which plays vital role in cellular physiological functions.In this study,to improve the L-cysteine production of the Escherichia coli MCYS-7,optimization of the culture medium was firstly performed by response surface methodology in flask fermentation.With a exogenous addition of betaine,amino acids and other chemicals,the fermentation process optimization and scale-up were carried out in 2 L bioreactors.The optimum culture medium was determined to be glucose(42.69 g/L),ammonium sulfate(7.77 g/L),yeast powder(6.53 g/L),sodium thiosulfate(6.22 g/L).In the flask fermentation after medium optimization,the titer of L-cysteine was significant improved to 3.85 g/L,which was increased by 169%compared with that before optimization.The scale-up results in the 2 L bioreactors revealed that,with the addition of exogenous chemical,the titer for L-cysteine production could reach 10.25 g/L after 47 h of fermentation.Our results laid a foundation for the L-cysteine production through microbial fermentation in industrial scale.

关 键 词：L-半胱氨酸 大肠杆菌 响应面 外源添加 发酵优化 

分 类 号：TQ922[轻工技术与工程—发酵工程]