The effect of storage time on tea Polyphenols, catechin compounds, total flavones and the biological activity of Ya’an Tibetan tea (Camellia sinensis)

摘要

The content of tea polyphenols (TPP), tea total flavones (TFS) and tea catechin compoundsin Ya’an Tibetan tea after different storage times was investigated, and theα-glucosidaseinhibition activity and antioxidative activity of tea were measured.Moreover, the correlation between the levels of tea catechins in Ya’an Tibetan teawith different storage years and their bioactivities were evaluated. During the periodof storage, the content of Tibetan tea polyphenols decreased, and the content ofTibetan tea flavonoids increased significantly. Five catechins were identified in Ya’anTibetan tea using UPLC-QqQ-MS/MS, and the Ya’an Tibetan tea had diverse antioxidantactivities and α-glucosidaseinhibitory activities over different storage years,due to the various tea catechin components. (-)-epigallocatechingallate (EGCG),(-)-epicatechingallate (ECG), and (-)-epicatechin(EC) were found to be responsible forits strong antioxidant activity and α-glucosidaseinhibitory activity, indicating Ya’anTibetan tea has potential as a functional food.