Metabolomics analyses reveal anthocyanins-rich accumulation in naturally mutated purple-leaf tea (Camellia sinensis L.)

Several purple-leaf tea has been utilized around the world. Flavonoids accumulation is one of the reasons why purple-leaf tea has unique pharmacological value and flavor. Although abundant researches have focused on identification the key genes associated with flavonoids biosynthesis in purple-leaf tea cultivars, However, the accumulation pattern of flavonoids in purple-leaf tea is still worth investigation. Here, a group of local purple-leaf tea varieties ('Baitangziyacha', BTZY), which are derived from the natural mutant of green-leaf tea varieties ('Baitangshancha', BTSC), were found in China. To evaluate the available value of purple-leaf tea varieties, 11 'BTZY' and 9 'BTSC' varieties were used to analyze the accumulation of flavonoids by widely targeted metabolomic analyses. The results showed that 259 secondary metabolites were characterized, of which 250 metabolites were flavonoids. Principal component analysis (PCA) analysis indicated 'BTZY' and 'BTSC' varieties were not completely classified may be due to differences in the accumulation of a few metabolites. Furthermore, these results found that 6 types of anthocyanins 5 types of flavonols were significantly up-regulated in purple-leaf varieties. These metabolites potentially contributed to the unique color and flavor of purple-leaf tea. Our findings will be useful for the further breeding and processing of local purple-leaf tea varieties.