DOI: 10.3746/jfn.2010.15.3.213 Antioxidant Activities and Melanogenesis Inhibitory Effects of

To examine the potential of Terminalia chebula as a whitening agent, we measured antioxidant activity using DPPH · , ABTS·+ assays and ferric-reducing antioxidant power (FRAP) assays, and depigmenting activity using B16F10 melanoma cells. The intracellular reactive oxygen species (ROS) level was monitored by H2DCFDA fluo-rescence labeling, and melanin contents in B16F10 melanoma cells by 960 J/m2 dose of UVA-induced oxidative stress. The radical-scavenging activities of T. chebula extract (TCE) were measured in terms of EC50 values using DPPH·, ABTS·+ assays and FRAP value were 280.0 μg/mL, 42.2 μg/mL and 113.1 μmol FeSO4 ․ 7H2O/g, respectively. We found that ROS and melanin concentrations were reduced by TCE treatments of 25 μg/mL under UVA-induced oxidative stress. Tyrosinase activity and melanin contents in α-melanocyte stimulating hormone (MSH)-induced melanoma cells both decreased dose-dependently in the treatment groups. TCE similarly reduced melanogenesis in B16F10 melanoma cells stimulated by α-MSH as compared to arbutin as a positive control. T. chebula may prove to be a useful therapeutic agent for hyperpigmentation and an effective component in skin whitening and⁄or lightening cosmetics