The chemical composition and melanin inhibitor activities of Mahonia nepalensis

Abstract

   Mahonia nepalensis DC.1821 (Hoang Lien O Ro) is widely distributed in the high mountainous areas at altitudes 1,700 - 1,900m of Vietnam as Lai Chau, Lao Cai, Ha Giang, Cao Bang, Bac Can and Lam Dong provinces. The stem bark and wood of Mahonia nepalensis were considered to have anti-inflammatory, anti-bacterial and antifungal activities and they are used particularly for the treatment of skin diseases. However, the effect of Mahonia nepalensis on melanin inhibition was not well-documented. In continuing to serarch new materials for skin whitening angents from natural resources, we investigated the effect of Mahonia nepalnensis DC. on the melanin synthesis in B16F10 melanoma cells. The results indicated the methanol extract of this plant did not show any significantly toxicity to B16F10 melanoma cells at even high concentration (up to 200μg/ml) and could significantly inhibit the melanin content. At the concentration of 100μg/ml, it could inhibit 37,15% of melanin formation in the B16F10 melanoma cells (compared with Arbutin, the well - known commercial melanin inhibitor, could inhibit 20,25% of melanin content at the concentration of 200μg/ml). This plant also showed free radical scavenging activity with IC50 = 346μg/ml. In conclusion, the methanol extract of Mahonia nepalensis could be used as an effective whitening ingredient in cosmetic products. The isolation of single active compound is on process.