Patchouli Alcohol: A Potent Tyrosinase Inhibitor Derived from Patchouli Essential Oil with Potential in the Development of a Skin-Lightening Agent

The inhibitory effects of Pogostemon cablin essential oil (patchouli essential oil, PEO) and its primary bioactive compound, patchouli alcohol (PA), on tyrosinase and melanin were investigated in vitro and ex vivo. Treatment with PEO and PA significantly, as well as dose-dependently, reduced forskolin (FRK)-induced melanin biosynthesis, cellular tyrosinase activity, and tyrosinase (TYR) protein expression. However, the transcriptional levels of TYR and tyrosinase-related proteins (TRP-1 and TRP-2) remained unaffected. These results suggest that PEO and PA may directly interrupt tyrosinase enzyme activity, leading to a reduction in melanin biosynthesis. Further experiments supported this notion, revealing that both PEO and PA significantly and dose-dependently inhibited mushroom tyrosinase activity in both the monophenolase and diphenolase phases. Additionally, an in silico molecular docking analysis was performed, utilizing a homology model of human tyrosinase. In conclusion, these findings strongly suggest that patchouli essential oil and its primary bioactive component, patchouli alcohol, hold promise as potential treatments for hyperpigmentary skin conditions and in the development of cosmetic products designed to lighten the skin.