Inhibition of Melanin Synthesis and Skin Whitening Effect by Heat—induced Yeast Extract（Cerepron(R)）

Objectives The aim of this study is to investigate the effect of a newly developed heat-induced yeast extract（Cerepron(R)）on melanin synthesis and on human skin whitening. Methods The heat-induced yeast extract（Cerepron(R)）was added to mouse melanoma B16 cells, and the inhibitory effect on melanin synthesis was evaluated. To elucidate its inhibitory mechanism on melanogenesis, tyrosinase assay and quantitative real-time RT-PCR for tyrosinase gene expression were carried out. Then, the skin whitening effect of the yeast extract was evaluated in a clinical trial. Results The heat-induced yeast extract inhibited melanin synthesis in a concentration-dependent manner （1-5 mg╱mL）. The yeast extract did not inhibit the enzymatic activity of mushroom-derived tyrosinase up to 2 mg╱mL, but did suppress the expression of tyrosinase mRNA in a concentration-dependent manner （1-5 mg╱mL）. In the clinical trial, the daily intake of 100 mg of the yeast extract for 8 weeks exhibited significant skin whitening effect. Conclusions The newly-developed heat-induced yeast extract （Cerepron(R)）has inhibitory effect on melanin synthesis by suppressing tyrosinase gene expression, which leads to human skin whitening effect. Therefore, Cerepron(R) as a promising skin whitening material can serve both for cosmetic and dietary supplements.