Xie_2025_Int.J.Biol.Macromol_308_142620

Galloylated catechins are major catechins in tea, resulting in a bitter and astringent taste. In this study, to identify the key genes involved in the hydrolysis of astringency-associated galloylated catechins in Camellia sinensis, multiomics association analysis, including enzyme activity assays, transcriptomics, and metabolomics, was performed. Subsequently, seven candidate genes involved in the hydrolysis of galloylated catechin were screened from tea genomes using correlation analysis. Phylogenetic analysis revealed that these genes were clustered into caffeoyl shikimate esterase, acetate esterase, and tannase groups. In vitro, the purified recombinant enzymes rCSS0031888 and rCSS0049322 catalyzed the hydrolysis of galloylated catechins into nongalloylated catechins. This study provides an efficient method for mining functional genes and identifying key genes involved in the hydrolysis of galloylated catechins in vitro, thereby reducing the bitterness and astringency of tea and offering a molecular basis for cultivating high-quality tea varieties.