Metabolome profiling unveil the composition differences of quality of different tea cultivars
Xuecheng Zhao, Ning Chi, Xiaoying Xu, Jun Lai, Jiedan Chen, Liang Chen
Abstract
Tea plant is abundant in bioactive compounds, including flavonoids, amino acids, alkaloids, terpenoid and lipids, and those are main affecting tea quality and flavors. Despite there are many studies of metabolites about different tea cultivars, the composition differences of their biosynthesis and regulation remains still unknow. In this study, 505 metabolites were detected from the apical bud and 1<sup>st</sup> leaf of ('Shuchazao': 'SCZ', 'Huangkui': 'HK' and 'Zijuan': 'ZJ' for short) using widely-targeted metabolomics, including 192 flavonoids, 45 lipids, 59 amino acids and derivatives, and 28 phenolamides. Metabolite analysis showed that flavonols and anthocyanins are mainly distributed in the form of glycosides in three cultivars, wherein anthocyanins and its glycosides are mainly accumulated in 'ZJ', indicating a correlation with the color attributes. EGCG emerged as the most abundant flavan-3-ols compound among the three cultivars. while L-theanine represented the predominant free amino acid, mainly concentrated in the apical bud compared to the 1<sup>st</sup> leaf, likewise, lipids are similar to free amino acids, mainly accumulating in the apical buds of three cultivars. These findings offer valuable insights into the genetic and metabolite diversity, augmenting our understanding of the biosynthesis of specific metabolites in tea plants.