为研究中高温大曲己酸菌群组成，以4种四川省内不同中高温大曲为研究对象，用富集培养基进行富集后对大曲和大曲富集液样本宏基因组DNA进行16S rRNA基因扩增子高通量测序，分析大曲中的己酸菌群组成。结果表明，经富集后，大曲潜在己酸菌群多样性和丰度增加，在大曲中潜在的优势己酸菌（相对丰度大于1%）包括Clostridium_sensu_stricto_18占2.19%~69.00%、Clostridium_sensu_stricto_15占1.76%~7.65%以及少量的Clostridium_sensu_stricto_12、Clostridium_sensu_stricto_1、Clostridium_sensu_stricto_10、Clostridium_sensu_stricto_7和Caproiciproducens。其中，Q1大曲以Clostridium_sensu_stricto_18、Clostridium_sensu_stricto_15；Q2大曲以Clostridium_sensu_stricto_1、Caproiciproducens、Clostridium_sensu_stricto_18；Q3大曲以Clostridium_sensu_stricto_18、Caproiciproducens；Q4大曲以Clostridium_sensu_stricto_18、Clostridium_sensu_stricto_1为主要的潜在己酸菌群组成。研究表明四川省内不同中高温大曲的己酸菌群组成存在差异，对其进行了初步分析，为大曲中己酸菌的定向研究提供理论依据，也为制备优质大曲促进浓香型白酒酒质的提升提供方向。

In order to study the composition of caproic acid-producing bacterial community in Medium/high-temperature Daqu, four different medium/high-temperature Daqu in Sichuan were used as the research objects. After the enrichment with the enrichment medium, the metagenomic DNA of Daqu and Daqu enrichment liquid samples were subjected to high-throughput sequencing with 16S rRNA gene amplicons, and the composition of caproic acid-producing bacterial community in Daqu was analyzed. The results showed that the diversity and abundance of the potential caproic acid-producing bacterial community in Daqu increased after the enrichment. The potential dominant caproic acid-producing bacteria (relative abundance >1%) in Daqu included Clostridium_sensu_stricto_18 (2.19%~69.00%), Clostridium_sensu_stricto_15 (1.76%~7.65%) and a small amount of Clostridium_sensu_stricto_12, Clostridium_sensu_stricto_1, Clostridium_sensu_stricto_10, Clostridium_sensu_stricto_7 and Caproiciproducens. Among them, in terms of the main potential caproic acid-producing bacterial community, Q1 Daqu was dominant with Clostridium_sensu_stricto_18, and Clostridium_sensu_stricto_15; Q2 Daqu was dominant with Clostridium_sensu_stricto_1, Caproiciproducens, and Clostridium_sensu_stricto_18; Q3 Daqu was dominant with Clostridium_sensu_stricto_18, and Caproiciproducens; Q4 Daqu was dominant with Clostridium_sensu_stricto_18, and Clostridium_sensu_stricto_1. The results showed that there were differences in the composition of caproic acid-producing bacterial communities in different medium/high-temperature Daqu in Sichuan. The preliminary analysis was carried out to provide a theoretical basis for the directional study of caproic acid-producing bacteria in Daqu, and also provide a direction for the preparation of high-quality Daqu to promote the quality improvement of Nongxiangxing liquor.

四川省科技创新创业苗子工程项目（23MZGC0042）；酿酒生物技术及应用四川省重点实验室开放基金项目（NJ2022-07）；四川江口醇隆鼎酒业有限公司院士（专家）工作站项目（HX2022065）