一株产γ-氨基丁酸屎肠球菌的筛选和发酵条件优化及其益生特性分析  

Screening and Optimization of Fermentation Conditions for γ-Aminobutyric Acid-Producing Enterococcus faecium and Analysis of Probiotic Properties

作　　者：孙擎 曾林 谭霄 张恕铭 孙向阳 汪杰 胡琼[1,2] 张庆 SUN Qing;ZENG Lin;TAN Xiao;ZHANG Shu-ming;SUN Xiang-yang;WANG Jie;HU Qiong;ZHANG Qing(Provincial Key Laboratory of Food Biotechnology of Sichuan,College of Food and Bioengineering,Xihua University,Chengdu 610039,China;Biotechnology Institute of Ancient Brewing,Xihua University,Chengdu 610039,China;Quality Inspection Co.,Ltd.of Sichuan,Luzhou 646000,China;Changdu Institute of Biology,Chinese Academy of Sciences,Chengdu 610041,China)

机构地区：[1]西华大学食品与生物工程学院,四川省食品生物技术重点实验室,四川成都610039 [2]西华大学古法发酵(酿造)生物技术研究所,四川成都610039 [3]四川国检检测有限责任公司,四川泸州646000 [4]中国科学院成都生物研究所,四川成都610041

出　　处：《食品工业科技》2020年第14期87-93,100,共8页Science and Technology of Food Industry

基　　金：四川省科技计划项目(2018NFP0111,2019ZYZF0170);四川省教育厅重点项目(18ZA0447)。

摘　　要：为拓宽产γ-氨基丁酸(γ-aminobutyric acid,GABA)微生物资源,以四川泡菜为分离源从中筛选高产GABA乳酸菌菌株,并对高产乳酸菌菌株进行生理生化、分子生物学鉴定,高产GABA发酵条件优化及其益生特性分析。结果表明:采用高效液相色谱对菌株产GABA能力分析发现菌株AB157的GABA产量最高为1.08 g/L。生理生化和16S rRNA鉴定菌株AB157为屎肠球菌(Enterococcus faecium)。通过单因素实验和响应面优化,确定屎肠球菌AB157的最佳培养条件为L-谷氨酸钠底物浓度5.2 g/L、发酵温度31℃、初始pH7、发酵时间70 h,在此条件下,屎肠球菌AB157的GABA产量达到1.60 g/L。屎肠球菌AB157的益生分析表明,其在pH2.0和3 g/L的胆盐环境中的存活率分别为39%和59%,胆固醇的脱除量为18.09μg/mL,说明该菌株具有良好的耐酸和耐胆盐特性以及较强的降胆固醇能力,可作为潜在功能性乳酸菌资源进行后续研究开发。In order to broaden and evaluate the microbial resources with capability of producingγ-aminobutyric acid(GABA),lactic acid bacteria(LAB)strains were isolated from Sichuan pickles.The higher GABA-producing LAB strain was identified using physiological and biochemical tests and phylogenetic analysis.And the fermentation conditions were also optimized using the response surface methodology.Meanwhile,the probiotic properties of GABA-producing strain were analyzed.The results showed that strain AB157 produced higher yield of GABA analyzed by high performance liquid chromatography(HPLC),and the content of GABA reached 1.08 g/L.Then the strain AB157 was further identified as Enterococcus faecium using physiological and biochemical tests and 16S rRNA gene sequence analysis.The optimal fermentation conditions were as follows:L-glutamate sodium concentration 5.2 g/L,fermentation temperature 31℃,initial pH7 and fermentation time 70 h.Under the optimized conditions,the production of GABA by E.faecium AB157 reached 1.60 g/L.The probiotic characteristics results showed that strain AB157 presented high survival rates in pH2.0 and 3 g/L bile salt circumstances,reached 39% and 59% respectively.Meanwhile,the cholesterol-reducing activity of the strain reached 18.09μg/mL.According to these results,E.faecium AB157 had better stress tolerance to acid and bile and stronger cholesterol-reducing activity.Therefore,E.faecium AB157 can be used as a potential functional LAB resource for further study.

关 键 词：屎肠球菌 Γ-氨基丁酸 筛选 鉴定 益生特性 发酵条件 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]