以芝麻香型白酒高温大曲为材料,采用55℃高温分离培养,通过平板透明圈法初筛和三角瓶固态发酵物蛋白酶活力测定复筛,分离筛选嗜热功能细菌,并结合16S rRNA基因序列分析和系统发育分析进行菌株鉴定。结果表明,55℃条件下共分离获得85株嗜热细菌,其中M5中性蛋白酶活力为96.06 U/g,优于对照菌株。菌株M5经分子生物学鉴定为枯草芽孢杆菌枯草亚种(Bacillus subtilis subsp.Subtilis),该菌株可制成微生物强化菌剂,应用于芝麻香型白酒的高温制曲过程中。

The high-temperature daqu of sesame flavor liquor was used as experimental samples.Thermophilic functional bacteria were isolated by culturing at 55℃.Through screening of transparent circle and assaying of the solid-state fermentation enzyme activity,protease production strains were isolated.The strains were identified with 16S rDNA gene phylogenetic analysis.The results revealed that 85 strains of thermophilic bacteria were isolated from samples.The neutral protease activity of M5 was higher than control strain,and the enzyme activity of M5 was 96.06 U / g.The strain M5 was identified as Bacillus subtilis subsp.subtilis through molecular biology methods.The strain M5 can be used as microbial agents to produce high-temperature daqu of sesame flavor liquor.