Effect of lu-duo-wei on scavenging superoxide and hydroxyl radicals in vitro.

Irradiation of a riboflavin-containing system by ultraviolet light was used to produce superoxide radical (.O2-). Hydroxyl radical (.OH) was generated by the system of Fe(II)-H2O2. Using electron spin resonance and spin trapping techniques, the effect of Lu-Duo-Wei, a capsule consisting extracts of green tea, Fructus Lycii and Semen Ziziphi Spinosae, on scavenging .O2- and .OH was observed. The results showed that the efficiency of scavenging .O2- and .OH by Lu-Duo-Wei was much higher than that by tea polyphenol alone. It is suggested that the synergistic action of tea polyphenol and other components are responsible for the scavenging effect of Lu-Duo-Wei on .O2- and .OH.