Cellular oxidative stress is caused by an imbalance in the redox status and manifests as hyperpigmentation disorders. Reactive oxygen species (ROS) including hydrogen peroxide (H2O2) promote the melanin production through the induction of tyrosinase enzyme activity. In this study, antioxidant activity of oxyresveratrol was investigated by 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Effects of oxyresveratrol on melanogenesis, tyrosinase activity and cellular oxidants in B16 cells were determined by melanin content assay, cellular tyrosinase activity assay and the dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay, respectively. Hydrogen peroxide induced melanogenesis through tyrosinase activity-related cellular oxidants, while oxyresveratrol showed potent antioxidant activity by DPPH and ABTS assays. At the concentrations of 10 and 12.5 µg/mll, oxyresveratrol significantly inhibited melanogenesis in B16 melanoma cells and also suppressed tyrosinase activity and cellular oxidants. Effective doses of oxyresveratrol inhibits melanogenesis through bioactivity of cellular tyrosinase-related oxidative stress.
Key words: oxyresveratrol, melanin, oxidative stress, tyrosinase