College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, Hubei 430070, People's Republic of China.
College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, Hubei 430070, People's Republic of China.
Int J Food Microbiol. 2022 Dec 2;382:109937. doi: 10.1016/j.ijfoodmicro.2022.109937. Epub 2022 Sep 17.
With the aim to reveal the microbial community succession at various temperatures in the fermentation of Qingzhuan tea (QZT), the Illumina NovaSeq sequencing was carried out to analyze bacterial and fungal community structure in tea samples collected from the fermentation set at various temperatures, i.e., 25 °C, 30 °C, 37 °C, 45 °C, 55 °C, and room temperature. The results showed that fermentation temperature profoundly affected the microbial community succession in the QZT fermentation. Microbial richness and community diversity decreased along with the increase of fermentation temperature. Despite the differences between microorganisms and their metabolic types among various temperatures, most bacteria and fungi showed positive correlations at the genera level. Klebsiella, Paenibacillus, Cohnella, and Pantoea were confirmed as the main bacterial genera, and Aspergillus and Cyberlindnera were the main fungal genera in QZT fermentation. The microbial genera (i.e. Aspergillus, Rhizomucor, Thermomyces, Ralstonia, Castellaniella, and Vibrio) were positively correlated with fermentation temperature (P < 0.05), while Klebsiella, Paenibacillus, and Aspergillus had good adaptability at different temperatures. Conversely, Pantoea and Cyberlindnera were only suitable for low temperature (≤37 °C) growth, and Thermomyces was only suitable for high temperature (>37 °C) growth. Aspergillus had a significant positive correlation with tea aroma quality (r = 0.64, p < 0.05). This study would help to understand the formation mechanism of QZT from microflora perspective.
为了揭示青砖茶发酵过程中不同温度下微生物群落的演替规律，采用 Illumina NovaSeq 测序技术，分析了在 25°C、30°C、37°C、45°C、55°C 和室温等不同发酵温度下采集的茶样中的细菌和真菌群落结构。结果表明，发酵温度对青砖茶发酵过程中的微生物群落演替有深远影响。微生物丰富度和群落多样性随发酵温度的升高而降低。尽管不同温度下的微生物及其代谢类型存在差异，但大多数细菌和真菌在属水平上呈正相关。在青砖茶发酵过程中，确定 Klebsiella、Paenibacillus、Cohnella 和 Pantoea 为主要细菌属，Aspergillus 和 Cyberlindnera 为主要真菌属。微生物属（即 Aspergillus、Rhizomucor、Thermomyces、Ralstonia、Castellaniella 和 Vibrio）与发酵温度呈正相关（P<0.05），而 Klebsiella、Paenibacillus 和 Aspergillus 在不同温度下具有良好的适应性。相反，Pantoea 和 Cyberlindnera 仅适合低温（≤37°C）生长，而 Thermomyces 仅适合高温（>37°C）生长。Aspergillus 与茶香气质量呈显著正相关（r=0.64，p<0.05）。本研究有助于从微生物菌群的角度了解青砖茶的形成机制。
