窖泥中酯化菌的筛选鉴定及协同发酵条件优化  

Screening and identification of esterifying bacteria from pit mud and conditions optimization of synergistic fermentation

作　　者：龚虎程 王宇 罗静 张家旭 田树林 边名鸿 高健 韩保林 GONG Hucheng;WANG Yu;LUO Jing;ZHANG Jiaxu;TIAN Shulin;BIAN Minghong;GAO Jian;HAN Baolin(College of Bioengineering,Sichuan University of Science&Engineering,Yibin 644005,China;Chengdu Shuzhiyuan Liquor Industry Co.,Ltd.,Chengdu 611335,China)

机构地区：[1]四川轻化工大学生物工程学院,四川宜宾644005 [2]成都蜀之源酒业有限公司,四川成都611335

出　　处：《中国酿造》2023年第12期81-86,共6页China Brewing

基　　金：四川轻化工大学研究生创新基金(Y2022097)。

摘　　要：该研究对窖泥中酯化菌进行筛选,通过形态学观察和分子生物学技术对筛选菌株进行鉴定。将筛选菌株与异常威克汉姆酵母(Wickerhamomyces anomalus)JM-4协同发酵,以酯化酶活力为指标,通过单因素及正交试验优化其发酵条件,并采用顶空固相微萃取结合气质联用(HS-SPME-GC-MS)技术分析发酵产物挥发性风味化合物。结果表明,获得3株酯化酶活力较高的细菌,分别编号为CY-1、CY-2、SY-3。菌株CY-1、CY-2、SY-3分别被鉴定为阿氏芽孢杆菌(Priestia aryabhattai)、地衣芽孢杆菌(Bacillus licheniformis)、暹罗芽孢杆菌(Bacillus siamensis)。将3株酯化菌与菌株JM-4协同发酵,其最优发酵条件为接种量6%、初始pH值为4.5、发酵时间48 h。在此优化条件下,酯化酶活力达到52.67 U/m L,是优化前的1.23倍。HS-SPME-GC-MS结果表明,协同发酵提高了挥发性风味化合物含量,产生了己酸、辛酸、2,3-丁二醇等挥发性风味化合物。In this study,esterifying bacteria were screened from pit mud,and the screened strains were identified by morphological observation and molecular biology techniques.The screened strains were co-fermented with Wickerhamomyces anomalus JM-4,and fermentation conditions were optimized by single factor and orthogonal experiments using esterification enzyme activity as evaluation index.The volatile flavor compounds of fermentation products were analyzed by headspace solid phase microextraction coupled with gas chromatography(HS-SPME-GC-MS) technique.The results showed that three bacterial strains with high esterification enzyme activity were obtained,numbered as CY-1,CY-2,and SY-3.The strains CY-1,CY-2 and SY-3 were identified as Priestia aryabhattai,Bacillus licheniformis and Bacillus siamensis,respectively.The three esterifying bacteria were co-fermented with strain JM-4,and the optimal fermentation conditions were obtained as follows:inoculum 6%,initial pH 4.5,fermentation time 48 h.Under these optimal conditions,the esterification enzyme activity reached 52.67 U/ml,which was 1.23 times that of before optimization.HS-SPME-GC-MS results showed that the content of volatile flavor compounds was increased by synergistic fermentation,and volatile flavor compounds such as caproic acid,caprylic acid and 2,3-butanediol were produced.

关 键 词：窖泥 酯化菌 筛选 鉴定 协同发酵 条件优化 

分 类 号：TS261.1[轻工技术与工程—发酵工程]