Distinct Chemical Profiles and Gut Microbiota Modulation of Ancha Tea Compared with Green and Black Teas from the Same Cultivar

Ancha tea (AT) is a type of dark tea processed through dew wetting. This study compared green tea (GT), black tea (BT), and AT, all derived from the same tea cultivar, to examine how processing methods influence chemical composition and health-promoting function. Nontargeted and targeted metabolomics revealed distinct chemical profiles among the three teas. In vitro fermentation with gut microbiota showed that all teas promoted beneficial bacteria, particularly Lactobacillus, while suppressing harmful genera, such as Escherichia-Shigella . All teas also enhanced the production of short-chain fatty acids (SCFAs). Among them, AT exhibited the most pronounced effects, including broader suppression of pro-inflammatory taxa and the highest SCFAs levels. Furthermore, in vivo experiments confirmed that all tea types consistently promoted Lactobacillus species, particularly Lactobacillus acidophilus and Lactobacillus vaginalis . These findings highlight the pivotal role of tea processing in shaping bioactive compound profiles and gut microbiota-modulating potential, with AT demonstrating superior functional properties.