Effect of Rhus coriaria L. (Anacardiaceae) on superoxide radical scavenging and xanthine oxidase activity.

Rhus coriaria L. (Anacardiaceae) is a well-known spice in the Middle-East and grown in the Central and East Anatolia region of Turkey. A methanolic extract (water-soluble part constituents) of R. coriaria, was found to be an uncompetitive inhibitor of xanthine oxidase and scavenger of superoxide radical in vitro with IC50 values of 172.5 microg/mL and 232 microg/mL respectively. Superoxide radicals were generated either by an enzymatic or a non-enzymatic system, and scavenging ability was evaluated by the inhibition of nitroblue tetrazolium reduction. This study provides evidence that a crude extract of R. coriaria exhibits interesting antioxidant properties, expressed either by the capacity to scavenge superoxide radical or to uncompetitively inhibit xanthine oxidase.