高产γ-氨基丁酸的棉子糖肠球菌的筛选、鉴定及其摇瓶发酵条件的优化  

Screening, identification and flask fermentation optimization of a high-yield γ-aminobutyric acid Enterococcus raffinosus strain

作　　者：陈慧敏[1] 高强[1] 苏喆[2] 王梦晓[1] 段强[1] 张云泽[1] 司晓光[1] 

机构地区：[1]天津科技大学生物工程学院、工业发酵微生物教育部重点实验室、工业酶国家工程实验室,天津300457 [2]天津市药品检验所,天津300070

出　　处：《微生物学通报》2012年第11期1642-1652,共11页Microbiology China

基　　金：国家863计划项目(No.2012AA021302);国家973计划项目(No.2011CB707401,2013CB734004);天津市滨海新区自主创新重大项目(No.2011-BK120014)

摘　　要：【目的】在中国传统发酵泡菜中分离出高产γ-氨基丁酸(γ-Aminobutyric acid,GABA)的乳酸菌。【方法】对分离自泡菜中的菌株M1进行形态观察、生理生化特性鉴定及其16S rDNA序列分析,实验采用单因素和正交设计对以MRS培养基为基础的GABA发酵培养基与摇瓶发酵条件进行了优化。【结果】菌株M1的形态培养和生理生化特征均符合肠球菌属(Enterococcus)特征,其16S rDNA序列与Enterococcus raffinosusSS1278 16S rDNA序列同源性达99%,鉴定为棉子糖肠球菌(Enterococcus raffinosus)。优化该菌株产GABA的发酵培养基的实验发现,最佳摇瓶发酵条件为:接种量10%,发酵温度30°C,培养初始pH 5.5,发酵周期60 h,谷氨酸一钠底物浓度10%,GABA产量提高了1.22倍。【结论】棉子糖肠球菌(E.raffinosus)M1菌株具有工业化发酵生产GABA的潜力。[Objective] A high-yield γ-aminobutyric acid （GABA） producing lactic acid bacte- rium （LAB）, strain M1 was isolated from pickled Chinese vegetables by our laboratory. [Methods] Its physiological and biochemical characteristics and 16S rDNA sequence were analyzed. GABA fermentation medium, based on MRS medium, was optimized using single factor test and orthogonal design, as well as the shake flask condition for GABA fermentation. [Results] The results indicated that the morphological, physiological and biochemical charac- teristics of strain M 1 were accorded with Enterococcus family. The identity between the obtained 16S rDNA sequence of strain M1 and Enterococcus raffinosus SS1278 was up to 99%, strain M1 was accordingly identified as Enterococcus raffinosus. Moreover, its GABA fer- mentation medium was optimized, and the shake flask condition for GABA fermentation was： inoculum of 10%, growing temperature at 30℃, initial pH at 5.5, fermentation period of 60 h and monosodium glutamate substrate concentration of 10%. Under these conditions, GABA yield by flask fermentation achieved a 1.22-fold increase. [Conclusion] The isolated E. raffi- nosus M1 strain reveals its potential for industrial fermentation of GABA.

关 键 词：Γ-氨基丁酸 棉子糖肠球菌 泡菜 分离鉴定 培养基与发酵优化 

分 类 号：TQ921[轻工技术与工程—发酵工程]