陈国伟 贾娇 杜丹 解修超 耿敬章 邓百万

摘 要：对谢村黄酒酒曲中细菌进行分离，利用薄层层析法定性、柱前衍生高效液相色谱法定量筛选出1株产γ-氨基丁酸（Gama-aminobutyric，GABA）能力的菌株N1，通过对该菌株进行形态学观察、生理生化试验、16S rDNA序列分析鉴定，并绘制其生长曲线，研究谷氨酸钠（L-MSG）的添加量、发酵时间、发酵温度等对菌株N1发酵产GABA含量的影响。结果表明：经初筛得到的菌株N1，复筛测得发酵液中GABA含量为448.6 mg·L-1。结合形态学、生理生化及分子生物学鉴定菌株N1为枯草芽孢杆菌Bacillus subtilis，菌株N1在液体培养0～4 h处于延滞期，4～12 h处于指数期，12～16 h为稳定期，16 h之后为衰退期; 菌株N1最适培养条件为发酵时間72 h、发酵温度36℃、pH值6、接种量2%、装液量100 mL、谷氨酸钠添加量1%，在此条件下菌株N1发酵产GABA含量可达583.5 mg·L-1。

关键词：谢村黄酒酒曲;γ-氨基丁酸;分离鉴定;发酵特性

中图分类号：Q 93-331  文献标志码：A  文章编号：0253-2301（2021）12-0012-07

DOI： 10.13651/j.cnki.fjnykj.2021.12.003

Isolation， Identification and Fermentation Characteristics of γ-aminobutyric acid-producing Strains

CHEN Guo-wei1， JIA Jiao1， DU Dan1，3， XIE Xiu-chao1，2*， GENG Jing-zhang1， DENG Bai-wan1，2

（1. College of Biological Science and Engineering， Shaanxi University of Technology， Hanzhong， Shaanxi 723000， China;

2. Shaanxi Engineering Research Center of Edible and Medicinal Fungi， Hanzhong， Shaanxi 723000， China;

3. Xianyang Academy of Agricultural Sciences， Xianyang， Shaanxi 712000， China）

Abstract： The bacteria in the yellow rice wine koji of Xiecun were isolated， and a strain N1 which was capable of producing γ-aminobutyric acid （GABA） was quantitatively screened by using the methods of thin layer chromatography and precolumn derivatization high performance liquid chromatography. The morphological observation， physiological and biochemical tests， 16S rDNA sequence analysis and identification of the strain were carried out， and its growth curve was plotted， in order to study the effects of the addition amount of sodium glutamate （L-MSG）， fermentation time and temperature on the content of GABA produced by the strain N1. The results showed that the content of GABA in the fermentation broth was 448.6 mg·L-1 after the initial screening. Combined with the identification of morphology， physiology， biochemistry and molecular biology， the strain was identified as Bacillus subtilis. The strain was in the lag phase from 0 to 4 h after the liquid culture， the exponential phase from 4 to 12 h， the stable phase from 12 to 16 h， and the decline phase after 16 h. The optimum culture conditions for the strain N1 were as follows： fermentation time 72 h， fermentation temperature 36℃， pH value 6， inoculation amount 2%， liquid volume 100 mL， and sodium glutamate 1%. Under these conditions， the content of GABA produced by the strain N1 could reach 583.5 mg·L-1.

Key words： Yellow rice wine koji of Xiecun; γ-aminobutyric acid; Isolation and identification; Fermentation characteristics

黄酒（Huangjiu）源于中国，是世界三大酿造酒之一，被誉为“液体面包”[1-3]，具有悠久的文化历史，是我国古代礼仪的象征[4]。谢村黄酒产自陕西省汉中市洋县，起源于上古夏商时期，民间有“南有绍兴加饭，北有谢村黄酒”之说，谢村黄酒是一种具有营养保健功能的发酵型低酒精度酒，2010年已被纳入陕西省第一批非物质文化遗产[5]。据鉴定，谢村黄酒富含17种人体必需氨基酸，总含量高达115633.66 mg·L-1，比啤酒高11倍，比红葡萄酒高8倍，比绍兴加饭酒高出1倍多[6]。“曲为酒之骨”[7-8]，酒曲作为酒中产生各种风味物质的动力源泉，其中微生物起到重要作用，微生物之间存在着共生、互生、寄生、拮抗的作用，在麦曲传统制作工艺中，微生物逐渐形成一个复杂并与环境相适应的微生物区系，决定着黄酒的品质[9]。……