基于高通量测序技术解析中高温制曲细菌群落的演替规律

High-Throughput Sequencing Revealed Succession Law of Bacterial Community in the Making of Medium-High-Temperature Daqu

为全面准确剖析中高温大曲发酵期的细菌群落更迭过程,本文采用高通量测序技术,对制曲各主要阶段不同分类水平的微生物信息进行了研究,结果表明:大曲刚入房时以乳杆菌属、肠杆菌科、魏斯氏菌属为主,并房后以魏斯氏菌属、乳杆菌属、明串珠菌属为主,上架时以乳杆菌属、魏斯氏菌属为主,大火中期以魏斯氏菌属为主,下架时芽孢杆菌属占据绝对优势,兼有一定占比的魏斯氏菌属,出房时则以魏斯氏菌属、乳杆菌属、葡萄球菌属、肠杆菌科为主,还有占比5%以上的高温放线菌属、片球菌属、芽孢杆菌属、明串珠菌属、克罗彭斯特菌属,物种最趋丰富,占比更趋均衡。此外,本文还首次通过Venn图、聚类热图、OTU进化图进行生物信息的可视化,结合Alpha多样性与PCoA分析细菌群落在中高温制曲过程中的分布特征,RDA分析显示酸度、水分与细菌群落的关联性最大。研究结果揭示了中高温大曲发酵过程中细菌群落结构及差异,有助于中高温大曲微生物多样性形成机制的解析,进而解析绵柔形成机理。

In order to fully and accurately analyze the bacterial community succession in the fermentation process of medium-hightemperature Daqu,we used high-throughput sequencing technology to study the microbial information at different classification levels in each major stage of Daqu production.The results showed that,when entering the fermentation room,Lactobacillus,Enterobacteriaceae and Weissella were the dominant bacteria;after combining the fermentation rooms,Weissella,Lactobacillus and Leuconostoc were the dominant bacteria;after putting on the shelves,Lactobacillus and Weissella were the dominant bacteria;in the middle of the fire period,Weissella was the dominant bacteria;after taking down from the shelves,Bacillus was the dominant genus,with a certain proportion of Weissella;when leaving the fermentation room,Weissella,Lactobacillus,Staphylococcus,and Enterobacteriaceae were the dominant bacteria,and Thermoactinomyces,Pediococcus,Bacillus,Mycelium,and Klopensteria accounted for more than 5%of the species.The species were the most abundant and the proportion was the most balanced when leaving the fermentation room.In addition,Venn map,cluster heat map and OTU evolution map were used to visualize the biological information.The distribution characteristics of bacterial community during fermentation were analyzed by combining Alpha diversity and PCoA.RDA analysis showed that acidity and moisture had the strongest correlation with bacterial community.This study has revealed the bacterial community structure and differences in the fermentation process of medium-high-temperature Daqu,which is helpful for the analysis of the formation mechanism of microbial diversity of Daqu.