Study on the Changes of Main Biochemical Components and the Efficacy of Thearubigins and Theabrownins in the Storage Period of Yunnan Black Tea

We selected the representative Yunnan high quality black tea as our experiment sample to test the main biochemical components of our experiment sample, such as tea pigment, caffeine, tea polyphenol etc. We used HPLC and spectrometry to detect the variation trend in the storage period (0, 1, 3, 5 years) of Yunnan black tea. Results showed that the content of caffeine, gallic acid (GA), epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) reduced; the content of theaflavins reduced, but the content of thearubigins and theabrownins increased. The results revealed the influence of storage time on the main chemical composition of black tea and provided a reference basis for the future. At the same time, we explored the effect of epidermal growth factor (EGFR) by using the thearubigins and theabrownins in mice skin tissues to explore the health benefits of black tea's tea pigment.