Regulation of melanin synthesis by selenium-containing carbohydrates.

This study reports depigmenting potency of selenium-containing carbohydrates, which would be based upon the finding of direct inhibition to mushroom tyrosinase. Two selenoglycosiede, SG-3 (bis(2,3,4-tri-O-acetyl-beta-D-arabinopyranosyl) selenide) and SG-8 (4'-methylbenzoyl 2,3,4,6-tetra-O-acetyl-D-selenomanopyranoside) among eleven selenium-containing compounds examined, were discovered to be effective depigmenting compounds on a mushroom tyrosinase inhibitory assay. SG-3 exhibited a competitive inhibition effect that was similar to kojic acid, well-known tyrosinase inhibitor. At 100 microM and 150 microM, SG-8 had an uncompetitive inhibitory effect that was higher than kojic acid. A study of a melan-a cell originated-tyrosinase inhibition assay showed that SG-8 had a lower inhibitory effect than kojic acid. SG-3 showed a similar inhibition effect to kojic acid on the melan-a cell-originated tyrosinase inhibitory assay. SG-8 showed dose-dependently cytotoxicity in a study of inhibition melanin synthesis by melan-a cells. Most melan-a cells did not survive after being treated with 20 microM of SG-8. At 10 microM, SG-3 inhibited melanin synthesis in the melan-a cells, and the effect was similar to phenylthiourea, which is a well-known inhibitor of melanin synthesis. Therefore, SG-3 is a new candidate for depigmenting reagents.