Combined use of versatile peroxidase and aryl alcohol oxidase of Pleurotus eryngii to decolorize melanin on the skin

Melanin plays an important role in protecting skin cells from harmful UV radiation, but its uneven pigmentation in the skin sometimes demands cosmetic resolution. As a safe and effective way of evening the skin tone, enzymatic decolorization of melanin at the stratum corneum has been proposed. In this regard, the use of lignin peroxidase, in the presence of hydrogen peroxide and veratryl alcohol, an electron mediator, has been explored. Here, we first show that versatile peroxidase (VP) and aryl alcohol oxidase (AAO) purified from the Pleurotus eryngii liquid culture can be used to decolorize melanin without exogenous hydrogen peroxide. This resembles the oxidative degradation pathway of lignin in nature; AAO generates hydrogen peroxide from veratryl alcohol, and VP utilizes generated hydrogen peroxide while using veratryl alcohol as a mediator. We further explored the use of POX_Pe, the crude peroxidase preparation of the Pleurotus eryngii liquid culture, for melanin decolorization because of its better stability. Using POX_Pe and veratryl alcohol, over 60 % of melanin decolorization was obtained in 1 h in the absence of exogenous hydrogen peroxide addition. Furthermore, POX_Pe could decolorize melanin in a 3D human pigmented epidermis model, demonstrating its possible applications in cosmetics.