Abstract: The extracts of Lycium chinense Mill fruits by water, 50% ethanol and 95% ethanol were compared in antiradical efficacy according to the Chinese consumption tradition. The results showed that water infusion was similar to 50% ethanol extractin flavonoids (1154±89mg/kg and 1207±66mg/kg, respectively), but 95% ethanol extract contained more flavonoids (1497±70mg/kg). The main flavonoids in Lycium chinense Mill fruits were rutin and chlorogenic acid in water extract, rutin andprotocatechuic acid in 50% ethanol extract and rutin in 95% ethanol extract respectively as assayed with high performancechromatography (HPLC). All extracts showed a slow kinetics in DPPH• antiradical reaction system. The antiradical efficacyof the extracts tended to become stronger as the polarity of the solvents became weaker.

Key words: boxthorn (Lycium chinense Mill), antiradical efficiency, DPPH•