alpha-Amyrin and beta-Amyrin Isolated from Celastrus hindsii Leaves and Their Antioxidant, Anti-Xanthine Oxidase, and Anti-Tyrosinase Potentials

Celastrus hindsii is a popular medicinal plant in Vietnam and Southeast Asian countries as well as in South America. In this study, an amount of 12.05 g of an alpha-amyrin and beta-amyrin mixture was isolated from C. hindsii (10.75 g/kg dry weight) by column chromatography applying different solvent systems to obtain maximum efficiency. alpha-Amyrin and beta-amyrin were then confirmed by gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR). The antioxidant activities of the alpha-amyrin and beta-amyrin mixture were determined via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,20-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays with IC50 of 125.55 and 155.28 mu g/mL, respectively. The mixture exhibited a high potential for preventing gout by inhibiting a relevant key enzyme, xanthine oxidase (XO) (IC50 = 258.22 mu g/mL). Additionally, an important enzyme in skin hyperpigmentation, tyrosinase, was suppressed by the alpha-amyrin and beta-amyrin mixture (IC50 = 178.85 mu g/mL). This study showed that C. hindsii is an abundant source for the isolation of alpha-amyrin and beta-amyrin. Furthermore, this was the first study indicating that alpha-amyrin and beta-amyrin mixture are promising in future therapies for gout and skin hyperpigmentation.