Anti-melanogenic effect of a novel oligosaccharide derived from almond on forskolin-stimulated melanogenesis in B16F10 melanoma cells

The application of natural products for regulating skin pigmentation is increasingly being acknowledged due to their security and proven efficacy. Almond (Amygdalus communis L.) is an edible nut plant with significant nutritional value and medicinal attributes. In this research, oligosaccharide (ACO-II-1) was extracted and isolated applying gel chromatography techniques from the aqueous extract of almond kernel. Structural characterization of ACO-II-1 was conducted using ESI-MS, methylation analysis and 1D/2D-NMR. The findings indicated that ACO-II-1 was composed of fructose and glucose and the glycosidic bond predominantly featured β-D-Fruf-(1 → 2)-β-D-Fru-(1 → 6)-α-D-Glcp-(1 → 1)-α-D-Glcp. Moreover, ACO-Ⅱ-1 possessed strong antioxidant activity and notable inhibitory effect on melanogenesis in forskolin (FSK)-induced B16F10 melanoma cells. Subsequent mechanism investigation was conducted and suggested that the anti-melanogenic properties of ACO-Ⅱ-1 might be attributed to its modulation of the Mitogen-activated protein kinases (MAPKs) and β-catenin signaling pathways. These results indicated that edible plant derived ACO-II-1 might be served as promising inhibitor of hyperpigmentation with potential application in pharmaceutical and skin-care sector.