Reactive oxygen species (ROS) are known to lead to oxidation of lipids, proteins, and DNA and cause skin damage. Moreover, ROS promote melanogenesis, which causes melasma, age spots, and freckle. The main compounds of the herbal medicines Poria cocas, Glycyrrhiza uralensis, and Ulmus macrocarpa were reported to be parchymic acid, glabridin, and flavonoids, respectively. The aim of this study was to investigate the whitening and antioxidant effects of a mixture of P. cocas, G. uralensis, and U. macrocarpa extracts (PGUE) in B16F1 cells to develop whitening cosmetics. PGUE inhibited DPPH radicals and lipid peroxidation, in addition to high reduction power, compared with Glycyrrhiza uralensis ethylacetate extracts (GUEE). Furthermore, PGUE exhibited a protective effect against DNA oxidation induced by the hydroxyl radicals. In addition to its antioxidant activity, the inhibitory activity of PGUE against tyrosinase, which is associated with melanogenesis, was greater than that of arbutin used as a positive control. Moreover, PGUE exerted an inhibitory effect on melanin synthesis in live melanoma cells and reduced the expression levels of superoxide dismutase-1 (SOD-1) and tyrosinase related protein-1 (TRP-1). These results indicate that PGUE has skin whitening and antioxidant effects, suggesting that this mixture can be used as the main ingredient in the development of effective whitening cosmetics.

Ginseng has been known to be highly effective for health as a traditional medicinal herb. Ginseng berry, or fruit of ginseng, contains ginsenoside, saponin, polyphenol, polyacetylene, alkaloid, etc. as the main compounds as does ginseng. The aim of this study is to evaluate any effect of ginseng berry water extract (GBE) on diabetic-associated molecules, such as enzymes, which are responsible for the glucose entry of the cells and the insulin receptor signaling molecules using HepG2 cells. Therefore, two enzymes, α-amylase and α-glucosidase, were selected and assayed for their activities in the presence of GBE in vitro. These two enzymes are responsible for producing glucose from dietary starch.Protein-tyrosine phosphatase 1B (PTP1B) and Akt1 are key proteins in the insulin receptor signaling pathway. These two intracellular signaling molecules were investigated for their expression levels in HepG2 cells after insulin and GBE treatment. GBE, at concentrations up to 1,000 μg/ml, did not exert any inhibitory effect on α-amylase and α-glucosidase. It was observed that the expression level of PTP1B was increased by insulin and the 25 μg/ml GBE treatment enhanced the PTP1B level. However, GBE at a concentration of 200 μg/ml reduced the expression level of PTP1B. In the case of Akt1, the Akt1 level by insulin was decreased by GBE treatment. These data suggest that the water extracts of ginseng berry have an influence on intracellular signaling by insulin.

Poria cocas has been reported to be effective in skin whitening. However, the direct effect of P. cocas ethanol extracts (PCEE) on melanin synthesis has not been scientifically studied. To elucidate the direct effect of PCEE on melanogenesis, a 3,4-dihydroxyindole-2-carboxylic acid (DOPA) synthesis assay, tyrosinase activity assay, and Western blotting for melanogenic proteins, including tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 were performed in mouse B16F1 cells. The results revealed that PGEE inhibited melanin production in a dose-dependent manner by blocking the synthesis of DOPA. Although the activation of tyrosinase was not affected, the expression levels of TRP-1 and TRP-2 were controlled. These results suggest that PCEE has a whitening effect, indicating that it may be a useful agent in the development of whitening cosmetics.