Objective    To appraise the in vivo and in vitro antioxidant effect of polyphenol extracts from Chinese flowering quince.     Methods    DPPH radical scavenging system was adopted to evaluate the EC

50

and kinetic indexes of the polyphenol extracts which were respectively supernatant without cellulase digestion

supernatant with cellulase digestion

the alcohol extracts from the sediment after cellulase digestion or not. Polyphenol extracts of different concentrations (40

80

120

200 mg/kg) were intragastrically administered to Kunming mice at dose of 0.1 ml/kg for 30 days

the total body gamma irradiation (

60

Co) was used to establish the mice model of peroxidation injury. Meanwhile the normal control group and irradiation model group without polyphenol extracts interference were set. On the third day after irradiation

MDA contents a

nd SOD activity in mouse serum and tissues were observed.      Results    Polyphenol extracts from Chinese flowering quince had strong effect against free radical in vitro and in vivo. The intervention of polyphenol extracts can effectively reduce the MDA contents and increase the SOD acvtivity in mice.     Conclusion    Polyphenol extracts from Chinese flowering quince have strong antioxidant effect both in vitro and in vivo.