New tyrosinase inhibitors, (+)-catechin-aldehyde polycondensates.
In this study, new tyrosinase inhibitors, (+)-catechin-aldehyde polycondensates, have been developed. Tyrosinase is a copper-containing enzyme that catalyzes the hydroxylation of a monophenol (monophenolase activity) and the oxidation of an o-diphenol (diphenolase activity). In the measurement of tyrosinase inhibition activity, (+)-catechin acted as substrate and cofactor of tyrosinase. On the other hand, the polycondensates inhibited the tyrosine hydroxylation and L-DOPA oxidation by chelation to the active site of tyrosinase. The UV-visible spectrum of a mixture of tyrosinase and the polycondensate exhibited a characteristic shoulder peak ascribed to the chelation of the polycondensate to the active site of tyrosinase. Furthermore, circular dichroism measurement showed a small red shift of the band due to the interaction between tyrosinase and the polycondensate. These data support that the polycondensate acts as an inhibitor of tyrosinase.
Kim
Young-Jin
YJ
Department of Materials Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
Chung
Joo Eun
JE
Kurisawa
Motoichi
M
Uyama
Hiroshi
H
Kobayashi
Shiro
S
D000363:Agaricales / Q000201:enzymology; D000447:Aldehydes / Q000737:chemistry / Q000494:pharmacology; D002392:Catechin / Q000737:chemistry / Q000494:pharmacology*; D002942:Circular Dichroism; D004563:Electrochemistry; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D013053:Spectrophotometry
D000447:Aldehydes; D004791:Enzyme Inhibitors; D002392:Catechin; D014442:Monophenol Monooxygenase