Effect of Cold Green Tea (Camellia sinensis L.) Extract Derived from Different Cropping Periods or Cultivars on Phagocytic Activity of Macrophage-like Cells

Abstract

The activation of mucosal immunity by drinking of green tea extraction with a high EGC ratio was positively correlated with the activation of macrophage phagocytosis by the green tea extract. Therefore, we estimated the effect of green tea extract derived from different cropping periods or cultivars using phagocytic activity of macrophage-like cells, so that the necessary condition to activate the macrophage phagocytosis was over 2 ratio of EGC to EGCG. The tea leaves harvested in late seasons include many catechins; therefore, the use of the late season leaves is effective way to get many catechins. Moreover, catechins content in tea leaves differs among cultivars. In this study, “Yutakamidori” was high EGC content cultivar.