Scavenging effects of Mallotus repandus on active oxygen species.

The active oxygen species scavenging potencies of Mallotus repandus (Willd.) Muell.-Arg. extracts were evaluated by the electron spin resonance (ESR) spin-trapping technique. Superoxide radical (O2.-) and hydroxyl radical (OH.) were supplied enzymatically from hypoxanthine-xanthine oxidase (HPX-XOD) reaction and hydrogen peroxide-ferrous sulfate (Fenton reaction), respectively, to the assay system. The ethyl acetate fraction of Mallotus repandus (stem) showed the greatest superoxide radical scavenger activity and the n-hexane fraction of Mallotus repandus (stem as well as root) the greatest hydroxyl radical scavenger activity.