The natural yeast extract isolated by ethanol precipitation inhibits melanin synthesis by modulating tyrosinase activity and downregulating melanosome transfer

Biosci Biotechnol Biochem. 2015;79(9):1504-11. doi: 10.1080/09168451.2015.1032880. Epub 2015 May 6.


This study was conducted to examine the effects of EP-2, a natural yeast extract isolated by ethanol precipitation from Saccharomyces cerevisiae, on melanogenesis and to determine its underlying mechanism of action. Our results show that although EP-2 is not a direct tyrosinase inhibitor, when EP-2 was added to the culture media of B16F10 melanoma cells, intracellular tyrosinase activity was decreased. However, EP-2 had no effect on the expression of microphthalmia-associated transcription factor or tyrosinase. EP-2 was found to inhibit melanogenesis and melanosome transfer when it was added to melanocytes and keratinocytes in coculture. In addition, protease-activated receptor 2, a key protein associated with melanosome transfer from melanocytes to keratinocytes, was downregulated in the presence of EP-2. In conclusion, EP-2 is a potent inhibitor of melanogenesis and its hypomelanogenic effect is related to the inhibition of tyrosinase activity and transfer of melanosomes.

Keywords: ethanol precipitation; melanogenesis; melanosome; tyrosinase; yeast.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Gene Expression Regulation, Neoplastic / drug effects
  • Melanins / biosynthesis*
  • Melanocytes / drug effects
  • Melanocytes / pathology
  • Melanoma, Experimental / drug therapy*
  • Melanoma, Experimental / enzymology
  • Melanoma, Experimental / pathology
  • Melanosomes / drug effects
  • Mice
  • Monophenol Monooxygenase / biosynthesis*
  • Oxidation-Reduction / drug effects
  • Saccharomyces cerevisiae / chemistry*


  • Melanins
  • Monophenol Monooxygenase