Figure 1.

Identification on the transformation of gallic acid into methyl gallate in tea plants. Control 1—tea branches fed with H₂O; Control 2—only [²H₂]gallic acid solution; Treatment—tea branches fed with [²H₂]gallic acid. As [²H₂]MG may be a byproduct of the chemical synthesis of [²H₂]GA standard, the same amount of [²H₂]GA was used as a control (Control 2). (A) Experimental setup of supplement of [²H₂]gallic acid into tea branches. The symbol (*) represents deuterium labelled. (B) quantitative analysis of synthesized [²H₂]methyl gallate in tea leaves fed with [²H₂]gallic acid. Data expressed as mean ± standard deviation (SD) (n = 3). Means distinguished with different letters are significantly different from each other among different groups.