From rhizosphere to gut: microbial drivers of tea flavor and bioactivity

Tea ( Camellia sinensis ) ranks among the most consumed beverages worldwide. Its commercial value rests on a flavor profile defined by umami and astringency, alongside antioxidant, anti-inflammatory, and metabolic health benefits 1 . Scholarly attention has long centered on secondary metabolites synthesized by the plant genotype under environmental stress, a tradition rooted in plant-endogenous phytochemistry 1 , 2 . L-theanine accounts for umami taste. Epigallocatechin gallate (EGCG), the dominant catechin, confers astringency and acts as the principal antioxidant 1 . Conventional research has accordingly focused on biosynthetic pathways internal to Camellia sinensis , especially enzymatic systems governing flavonoid and theanine production 1 , 2 , 3 . This framing proved productive for mapping individual biosynthetic steps, yet it obscures the ecological setting in which these pathways operate and the external biological agents that alter their output.