Effects of Quercetin on Mushroom Tyrosinase and B16-F10 Melanoma Cells

Molecules

Isao Kubo¹  Teruhiko Nitoda² 

[1] id="af1-molecules-12-01045">Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720-3114, U

关键词: Quercetin;    mushroom tyrosinase;    adducts;    murine B16-F10 melanoma cells;    cytotoxicity;   

DOI  :  10.3390/12051045

来源: mdpi

【 摘 要 】

In searching for tyrosinase inhibitors from plants using l-3,4-dihydroxyphenylalanine (l-DOPA) as a substrate, quercetin was found to be partially oxidized to the corresponding o-quinone under catalysis by mushroom tyrosinase (EC 1.14.18.1). Simultaneously, l-DOPA was also oxidized to dopaquinone and both o‑quinones were further oxidized, respectively. The remaining quercetin partially formed adducts with dopaquinone through a Michael type addition. In general, flavonols form adducts with dopaquinone as long as their 3-hydroxyl group is free. Quercetin enhanced melanin production per cell in cultured murine B16-F10 melanoma cells, but this effect may be due in part to melanocytotoxicity. The concentration leading to 50% viable cells lost was established as 20 μM and almost complete lethality was observed at 80 μM.

【 授权许可】

Unknown   
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