Widely targeted metabolomic analyses of albino tea germplasm 'Huabai 1' and 'Baiye 1'

'Huabai 1' is a novel albino tea germplasm that has a stable albino phenotype and prolonged albino period. In this study, widely targeted metabolomics was employed to analyze the metabolic profile of 'Huabai 1', and compare metabolites between albino shoots of 'Huabai 1' (HBW) and albino shoots of the broadest cultivated cultivar 'Baiye 1' (BYW). A total of 359 differential metabolites were identified in 'Huabai 1'. Comparative analysis of differential metabolites revealed that 83 and 161 differential metabolites were specific for HBW and BYW, respectively. The phenylpropanoid and flavonoids biosynthesis are the key metabolic pathways, contributing to the color change in 'Huabai 1', while the purine metabolism and lipid-related metabolites may play important roles in regulating albinism in 'Baiye 1'. Comparative analysis of amino acids and catechins revealed that the umami taste of albino tea may be due to the internal balance of amino acid components and the decrease in phenol-ammonia ratio. In addition, lipid-related metabolites, the main contributors to the aroma of tea, were significantly enriched in BYW, while, HBW possess higher antioxidative components than that of BYW, such as apigenin and genistein etc., suggesting that the 'Huabai 1' may have high prospects in commercialization and future breeding programs.