School of Life Sciences, Shaoxing University, Shaoxing 312000, China; National Engineering Research Center for Chinese CRW (Branch Center), Shaoxing 312000, China.
School of Life Sciences, Shaoxing University, Shaoxing 312000, China.
Food Res Int. 2023 Oct;172:113144. doi: 10.1016/j.foodres.2023.113144. Epub 2023 Jun 16.
The microbial ecosystem of fermented food is greatly disturbed by human activities.Jiuyao is important saccharification starter for brewing huangjiu. The interaction between environmental factors and microorganisms significantly affected the microbial community structure at different stages of Jiuyao manufacturing. This study combined environmental factor analysis and high-throughput sequencing technology to comprehensively analyze the specific changes of microbial community and environmental factors in each fermentation stage of Jiuyao production and their correlation. The results showed that the activities of liquefaction enzyme, glycosylation enzyme and acid protease reached the highest value on the 8 th day (192 h) after the beginning of fermentation, and the cellulase activity reached the highest value at the end of fermentation. Pediococcus（37.5 %-58.2 %）, Weissella（9.2 %-27.0 %） and Pelomonas（0.1 %-12.1 %） were the main microbial genera in the genus bacteria, and Saccharomycopsis（37.1 %-52.0 %）, Rhizopus（12.5 %-31.0 %） and Saccharomyces（4.0 %-20.5 %） were the main microbial genera in the genus fungi. The results of correlation analysis showed that the microbial communities in Jiuyao were closely related to environmental factors. Most microbial communities were positively correlated with temperature, but negatively correlated with ambient humidity, CO concentration, acidity and water content of Jiuyao. In addition, the transcription levels of enzymes related to microbial glucose metabolism in Jiuyao were higher in the late stage of Jiuyao fermentation. Interestingly, these enzymes had high transcription levels in fungi such as Saccharomycopsis, Rhizopus and Saccharomyces, as well as in bacteria such as Pediococcus and Lactobacillus. This study provides a reference for revealing the succession rule of microbial community structure caused by environmental factors during the preparation of Jiuyao in Shaoxing Huangjiu.
发酵食品的微生物生态系统受到人类活动的极大干扰。酒曲是黄酒酿造的重要糖化发酵剂。环境因素与微生物的相互作用显著影响了酒曲制作过程中不同阶段的微生物群落结构。本研究结合环境因素分析和高通量测序技术，全面分析了酒曲生产各发酵阶段微生物群落和环境因素的具体变化及其相关性。结果表明，液化酶、糖化酶和酸性蛋白酶的活性在发酵开始后第 8 天（192 h）达到最高值，纤维素酶活性在发酵结束时达到最高值。在细菌属中，主要的微生物属为肠球菌（37.5%-58.2%）、魏斯氏菌（9.2%-27.0%）和 Pelomonas（0.1%-12.1%），在真菌属中，主要的微生物属为酿酒酵母（37.1%-52.0%）、根霉（12.5%-31.0%）和酿酒酵母（4.0%-20.5%）。相关性分析结果表明，酒曲中的微生物群落与环境因素密切相关。大多数微生物群落与温度呈正相关，但与环境湿度、CO 浓度、酸度和酒曲含水量呈负相关。此外，酒曲中与微生物葡萄糖代谢相关的酶的转录水平在酒曲发酵后期较高。有趣的是，这些酶在酿酒酵母、根霉和酿酒酵母等真菌以及肠球菌和乳杆菌等细菌中具有较高的转录水平。本研究为揭示绍兴黄酒酒曲制备过程中环境因素引起的微生物群落结构演替规律提供了参考。
