International Tea Day

Green tea contains various water soluble macromolecules. GTND (green tea non-dialysate) is one of these (molecular weight more than 12,000. GTND has anti-tumor function. GTND suppressed duodenal tumors in mice induced by ENNG（N-ethyl-N’-nitro-N-nitrosoguanidine.  When 0.05 % GTND was administered to mice in the drinking water, the number of mice with tumors, the number of total tumors, the number of tumors per one mouse and the weight of tumor were suppressed compared with controls. The number of total tumors was suppressed significantly. No suppression was observed when the level of GTND was reduced by 0.005 %. Hetero-polysaccharides are other water soluble macromolecules of green tea that showed antiglycemic action.

  Japanese green tea leaves are rich in antioxidant vitamins, such as vitamin C, vitamin E and βcarotene. In addition to antioxidative activity, these vitamins have anti-tumor effects and suppress aging . Commercial Japanese green tea leaves contain vitamin C approximately 280 mg per 100 g dried weight. By administration of vitamin C to rats, lipid peroxidation of liver was decreased. Vitamin C has also antimutagenic effect. Japanese green tea leaves contain about 70 mg of vitamin E per 100 g dried weight. Vitamin E suppresses the peroxide lipid synthesis.β- carotene has a radical scavenging function which prevents skin cancer. Vitamin E and β-carotene are water insoluble matter. In order to ingest vitamin E and β- carotene, eating whole tea leaves as Matcha is necessary.