襄阳地区高温大曲发酵过程中细菌群落演替及PICRUSt基因功能预测分析

Bacterial Community Succession and PICRUSt Predictive Analysis of Gene Function during High-temperature Daqu Fermentation Process in Xiangyang Region

摘要:

该研究以采集的32 份不同发酵时期高温大曲作为研究对象，采用16S rRNA测序技术对高温大曲发酵过程中细菌群落多样性进行了解析，并结合PICRUSt软件对细菌基因功能进行了预测。研究结果显示，不同发酵时期高温大曲细菌丰富度和群落结构差异显著（P<0.05），且随着发酵的进行，细菌丰富度呈现先上升后下降的趋势，在一次翻曲时达到最高。高温大曲发酵过程中共检测到3 个优势细菌门和10 个优势细菌属，在不同发酵时期样品中具有明显的群落演替，同时从所有样品中共检测到10 个核心OTU，主要隶属于糖多孢菌属（Saccharopolyspora）、高温放线菌属（Thermoactinomyces）、芽孢杆菌属（Bacillus）、克罗彭斯特菌属（Kroppenstedtia）和慢生芽孢杆菌属（Lentibacillus），累积平均相对含量为52.62%。不同发酵时期高温大曲之间细菌微生物网络存在明显差异，其中一次翻曲样品的网络稳定性最高，且岩石芽孢杆菌属（Scopulibacillus）和Bacillus是维持高温大曲发酵过程中微生物群落结构稳定的关键细菌属。新陈代谢是高温大曲发酵过程中的重要功能通路，包括能源生产和转化以及氨基酸、碳水化合物、脂质等生物大分子运输和代谢。该研究强化了人们对高温大曲发酵过程中细菌群落演替的认识，同时为相关企业制曲工艺的优化和产品品质的改善提供了有益参考。

Abstract:

In this study, 32 samples of high-temperature Daqu at different fermentation periods were collected as research objects. 16S rRNA sequencing technology was used to analyze the bacterial community diversity during the high-temperature Daqu fermentation process, and the bacterial gene function was predicted by PICRUSt software. The results showed that the bacterial richness and community structure of high-temperature Daqu at different fermentation periods were significantly different (P<0.05). With the progress of fermentation, the bacterial richness showed a trend of first increasing and then decreasing, and reached the highest at the first-turned Daqu. A total of 3 dominant bacterial phyla and 10 dominant bacterial genera were detected during the high-temperature Daqu fermentation process, and there was obvious community succession in the samples at different fermentation stages. At the same time, a total of 10 core OTUs were detected from all samples, mainly belonging to Saccharopolyspora, Thermoactinomyces, Bacillus, Kroppenstedtia and Lentibacillus, with cumulative average relative abundance of 52.62 %. There were significant differences in bacterial microbial networks of high-temperature Daqu between different fermentation periods. Among them, the network stability of the first-turned Daqu samples were the highest, and Scopulibacillus and Bacillus were the key bacteria to maintain the stability of the microbial community structure during the high-temperature Daqu fermentation process. Metabolism was an important functional pathway in the high-temperature Daqu fermentation process, including energy production and transformation, as well as the transport and metabolism of biological macromolecules such as amino acids, carbohydrates and lipids. This study strengthens people 's understanding of the succession of bacterial communities during the high-temperature Daqu fermentation process, and provides a useful reference for the optimization of Daqu making process and the improvement of product quality in related enterprises.