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.
Department of Materials Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
Young-Jin
YJ
Kim
Joo Eun
JE
Chung
Motoichi
M
Kurisawa
Hiroshi
H
Uyama
Shiro
S
Kobayashi
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