HYDROXYL RADICAL AND SUPEROXIDE RADICAL SCAVENGING ACTIVITIES OF POLYPHENOL FROM RAPESEED AND VC IN MODIFIED CHEMICAL SYSTEMS Antioxidant and activated oxygen free radical scavenging activities of different extract from Siraitia grosvenorii Allelopathic Potential and Its Mechanism of Hypecoum erectum L. on Lettuce Antilipid peroxidation of polyamines from pilose antler Polysaccharides Extraction and Comparative Analysis on Antioxidative Activities in vitro of Hengshan Astragalus and Lycium barbarum