Effects of tea (Camellia sinensis) chemical compounds on ethanol metabolism in ICR mice.

The effects of a green tea (Camellia sinensis) extract on ethanol metabolism in ICR male mice were studied. A crude green tea extract (GTE) and the tea components as (-)-epigallocatechin gallate (EGCg), (-)-epigallocatechin (EGC), and caffeine were administered before the tests. One hour later, the mice were orally given 2g/kg body weight (b.w.) of ethanol (20% ethanol w/v). The results show that the levels in the blood and liver of ethanol and acetaldehyde were lower, and that the levels of acetate and acetone were higher than in the controls orally given 500 mg/kg b.w. of GTE. After the administration of 75 mg/kg b.w. and 225 mg/kg b.w. of EGCg, the acetate and acetone concentrations in the blood and liver were lower than in the controls. The mice given caffeine at the same dose as that in GTE showed almost the same effects as the group treated with GTE. This suggests that EGCg and caffeine, the principal components of GTE, both had an effect on ethanol metabolism.