title: Inhibitory effects of naphthols on the activity of mushroom tyrosinase.
abstract: Tyrosinase (EC 1.14.18.1), a copper-containing multifunctional oxidase, was known to be a key enzyme for biosynthesis in fungi, plants and animals. In this work, the inhibition properties α-naphthol and β-naphthol toward the activity of tyrosinase have been evaluated, and the effects of α-naphthol and β-naphthol on monophenolase and diphenolase activity of tyrosinase have been investigated. The results showed that both α-naphthol and β-naphthol could potently inhibit both monophenolase activity and diphenolase activity of mushroom tyrosinase, and that β-naphthol exhibited stronger inhibitory effect against tyrosinase than α-naphthol. For monophenolase activity, β-naphthol could not only lengthen the lag time but also decrease the steady-state activity, while α-naphthol just only decreased the steady-state activity. For diphenolase activity, both α-naphthol and β-naphthol displayed revisible inhibition. Kinetic analyses showed that both α-naphthol and β-naphthol were competetive inhibitors.
authors.affiliation: College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Yi-Fen
authors.initials: YF
authors.lastname: Lin
authors.forename: Yong-Hua
authors.initials: YH
authors.lastname: Hu
authors.forename: Yu-Long
authors.initials: YL
authors.lastname: Jia
authors.forename: Zhi-Cong
authors.initials: ZC
authors.lastname: Li
authors.forename: Yun-Ji
authors.initials: YJ
authors.lastname: Guo
authors.forename: Qing-Xi
authors.initials: QX
authors.lastname: Chen
authors.forename: He-Tong
authors.initials: HT
authors.lastname: Lin
mesh_terms: D000363:Agaricales / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D007700:Kinetics; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D009284:Naphthols / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D004791:Enzyme Inhibitors; D009284:Naphthols; D014442:Monophenol Monooxygenase