Changes of Antioxidative Activity During Florescence and Flower Senescenceof Peonies Petal Research on quality changes in ginseng stems and leaves before and after frost DPPH radical scavenging activities of 31 flavonoids and phenolic acids and 10 extracts of Chinese materia medica Chemical constituents with antioxidative activity from the flower buds of Lonicera serreana Study on Antioxidant Activity of Lithospermum erythrorhizon in vitro Preparation and anti-oxidative activity of hydroxytyrosol by alkaline hydrolysis of oleuropein Studies on release behavior of sustained release tablets of extracts of gardeniaby antioxidant activity Changes of Antioxidative Activity During Florescence and Flower Senescenceof Peonies Petal