该研究采用高通量测序技术对不同类型高温大曲细菌群落进行了解析，继而对其理化指标进行测定，同时对2者的相关性进行分析，最后使用纯培养技术对细菌资源进行挖掘。测序结果表明，黄色高温大曲中Thermoactinomyces、Limosilactobacillus和Weissella的平均相对含量显著偏高（P<0.05），分别为21.04%、14.30%和3.15%，Lentibacillus和Kroppenstedtia的平均相对含量显著偏低（P<0.05），分别为3.30%和2.81%，而其在黑色高温大曲中分别为1.93%、0.036%、0.027%、34.45%和20.75%。此外，LEfSe分析发现Thermoactinomyces和Lentibacillus可分别作为黄色和黑色高温大曲的生物标志物。理化指标测定显示，黄色高温大曲的水分含量、液化力、糖化力、酯化力和酒化力显著偏高（P<0.05），而酸度显著偏低（P<0.05）。相关性分析发现，优势细菌属与理化指标之间存在显著相关性（P<0.05）。采用纯培养技术从高温大曲样品中共分离得到33株细菌菌株，鉴定为5个属的10个种，主要以Bacillus 为主，且B. licheniformis为优势分离株，占分离株总数的30.30%。由此可见，2种类型高温大曲细菌群落与理化指标间均存在明显差异，且微生物与理化指标之间具有一定相关性。

Illumina MiSeq high-throughput sequencing was used to analyze the differences in bacterial community structure between yellow and black high-temperature Daqu. Subsequently, the physicochemical indices of Daqu samples were measured, and the correlations between bacterial community structure and physicochemical indices were analyzed. Finally, the pure culture technique was used to explore the bacterial populations present in the Daqu samples. The sequencing results showed that the average relative abundances of Thermoactinomyces (21.04%), Limosilactobacillus (14.30%), and Weissella (3.15%) in the yellow high-temperature Daqu were significantly higher (P<0.05) than those (1.93%, 0.036%, and 0.027%, respectively) in the black high-temperature Daqu, whereas the average relative abundances of Lentibacillus (3.30%) and Kroppenstedtia (2.81%) in the yellow high-temperature Daqu were significantly lower (P<0.05) than those (34.45% and 20.75%, respectively) in the black high-temperature Daqu. In addition, LEfSe analysis showed that Thermoactinomyces and Lentibacillus could be used as biomarkers for yellow and black high-temperature Daqu, respectively. The measurement results of physicochemical indices showed that compared to the black high-temperature Daqu, the yellow high-temperature Daqu exhibited significantly higher water content, liquefaction power, saccharification power, esterification power, and alcoholic power (P<0.05), and significantly lower acidity (P<0.05). Correlation analysis revealed significant correlations between the dominant bacterial genera and physicochemical indices in the two types of high-temperature Daqu (P<0.05). A total of 33 bacterial strains were isolated from high-temperature Daqu samples using the pure culture technique. The strains comprised ten species under five genera, with Bacillus being the dominant genus and B. licheniformis being the dominant isolate (accounting for 30.30% of the total number of isolates). Hence, the two types of high-temperature Daqu exhibited significant differences in bacterial community structure and physicochemical indices, and their bacterial community structures were correlated with their physicochemical indices.

湖北省自然科学基金计划襄阳创新发展联合基金项目（2023AFD049；2023AFB288）；邯郸市科学技术研究与发展计划项目（21212906064）；湖北文理学院教师科研能力培育基金“科技创新团队”（2020kypytd009）