Metagenomics-Based Insights into the Microbiota Drive Vitamins Metabolism In the Fermentation of Pu-Erh Tea

Abstract

The vitamins present in tea beverages are an essential nutrient, but their metabolism during the microbial fermentation of pu-erh tea is not fully understood. In this study, 28 vitamins were measured in an industrial fermentation of pu-erh tea, and microbial metabolic profiles were also investigated using metagenomic sequencing. After fermentation, the contents of 19 vitamins significantly decreased (p < 0.05). However, the contents of adenine, riboflavin, 5-formyltetrahydrofolate, and ergocalciferol increased significantly (p< 0.05). The microbial diversity, population structure and functional genes of pu-erh tea changed significantly during fermentation. functional genes related to carbohydrates, amino acids, vitamins, and lipids metabolism were identified. Most importantly, 52 enzymes (4035 genes), mainly from Pantoea, Pseudomonas, Rasamsonia, and Bacillus were found to be involved in vitamin metabolism. Overall, this study gives novel insights into the fermentation mechanism of ripen pu-erh tea by systematically revealing microbial functional genes associated with changes in vitamins during the fermentation.

Keywords: Vitamins, Pu-erh tea, Metagenomic analysis, Function microorganisms, Metabolic pathway