Preparation and anti-oxidant activity of cinnamic acid derivatives-g-CTS Antioxidation mechanism of phenolic compounds in black tea and its structure-activity relationship Chemical constituents from the leaves of Alchornea trewioides(Ⅲ). Quinic acids Extraction of total quantity flavone from Solanum photeinocarpum and its antioxidation activity Antioxidant Activity in Vitro of Glycoprotein from Chinese Yam Antioxidant Activity in Vitro of Glycoprotein from Chinese Yam