Sapindus mukorossi Seed Oil Changes Tyrosinase Activity of α-MSH-Induced B16F10 Cells Via the Antimelanogenesic Effect of Eicosenoic Acid

Melanogenesis is a complex process that can lead to pigmentation defects. Various chemical skin-lightening products have been developed to treat pigmentation disorders. However, these chemical products can cause harmful adverse effects. Therefore, the development of safer, natural bleaching ingredients is a trend for sustainability. It has been reported that unsaturated fatty acids exhibit significant antimelanogenic effects. Sapindus mukorossi seed oils contain abundant unsaturated fatty acids; however, these have not yet been investigated for beneficial effects on skin tone evenness. In this study, we tested the possibility of using S. mukorossi oil for the treatment of hyperpigmentation in an in vitro model. Free fatty acid compositions and β-sitosterol were determined by gas chromatography-mass spectrometry and high-pressure liquid chromatography, respectively. The effect of S. mukorossi oil on melanoma B16F10 cell viability was detected using the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl-tetrazolium bromide assay. The inhibitive effects of fatty acids and β-sitosterol in S. mukorossi oil on α-melanocyte-stimulating hormone (MSH)-induced melanogenesis was evaluated by detecting melanin formation and tyrosinase activity. Our results showed that S. mukorossi oil produced no significant cytotoxicity in B16F10 cells at various concentrations compared with the control group. The enhancement of melanin formation induced by α-MSH was reduced by S. mukorossi oil. We also found that the primary fatty acid contributing to the antimelanogenesis effect was eicosenoic acid. These results suggest that S. mukorossi seed oil can effectively inhibit melanogenesis and has the potential for future development as a de-hyperpigmentation product within a waste utilization context.