The Contents of Caffeine, Catechins, and Flavonol Glycosides in Tea Leaves （Camellia sinensis L.） during Winter Dormancy.

Abstract

Tea leaves （Camellia sinensis L.） during winter dormancy have been used to manufacture tea in some areas of Japan. Since little information is available on the ingredient contents of tea leaves during winter dormancy, we investigated the contents of caffeine, catechins, and flavonol glycosides of tea leaves harvested in October before wintering and February during dormancy. As results, the contents of caffeine, EGCG, and EGC in February decreased by approximately 50, 60, and 20%, respectively, compared with October. Most of the 16 investigated flavonol glycosides did not change, but the contents of Q-GRhG, Q-GRh, Q-Ga, Q-G, and K-GRh were increased in February compared with October.