SUPEROXIDE-SCAVENGING AND TYROSINASE-INHIBITORY ACTIVITIES OF THE EXTRACTS OF SOME CHINESE MEDICINES

The superoxide-scavenging and the tyrosinase-inhibitory activities of 28 kinds of plants used as Chinese medicines were evaluated. Methanol/ water extracts were used for the screening tests, and for those which represented high activities, other kinds of extracts were also studied . The extracts of Mallotus japonicus Muell. Arg. scavenged superoxide strongly; the half-inhibiting concentration (IC50) of its 50% methanol /water extract was 10.57 mu g of dried material in 1 ml of reaction mi xture. The extracts of Fritallaria thunbergii Miq., Carthamus tinctori us L., and Prunus persica (L.) Batsch had strong tyrosinase-inhibitory activities, and the extracts of Scutellaria baicalensis Georgi repres ented both kinds of activities. These facts suggested that Chinese med icines may be a treasure house of chemical compounds that have the sup eroxide-scavenging and the tyrosinase-inhibitory activities.