Article

Competitive inhibition of mushroom tyrosinase by 4-substituted benzaldehydes

Departamento de Bioquímica y Biología Molecular A, Unidad Docente de Biología, Facultad de Veterinaria, Universidad de Murcia, E-30080, Murcia, Spain.
Journal of Agricultural and Food Chemistry (Impact Factor: 3.11). 09/2001; 49(8):4060-3. DOI: 10.1021/jf010194h
Source: PubMed

ABSTRACT A kinetic study of the inhibition of mushroom tyrosinase by 4-substituted benzaldehydes showed that these compounds behave as classical competitive inhibitors, inhibiting the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) by mushroom tyrosinase (o-diphenolase activity). The kinetic parameter (K(I)) characterizing this inhibition was evaluated for all of the seven compounds assayed. Cuminaldehyde showed the most potent inhibitory activity (K(I) = 9 microM). It also inhibited the oxidation of L-tyrosine by mushroom tyrosinase (o-monophenolase activity) in a competitive manner. The corresponding kinetic parameter for this inhibition was evaluated (K(I) = 0.12 mM).

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    • "It suggested that the position of the substituent influenced the tyrosinase inhibitory potency, and in the investigation, the amide group at the position-4 of the phenyl ring was more efficacious for the inhibitory activity. It was consistent with previous reports by Kubo [17], Jimenez [18]. "
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    • "First 300 ȝL of 2.5 mM 3,4-dihydroxyphenylalanine (L-DOPA)solution was added to 700 ȝL of 0.1 M phosphate buffer (pH 7.5). The mixture was preincubated at 37Gfor 5 min and 100 ȝL of potato extract was added, and the reaction was monitored by dopachrome formation at 475 nm (İ = 3700 Mcm -1 ) (Jiménez et al., 2001 "
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    • "에 정리하였다. 앞서와 같이, 기질분자 중 hydroxyl-치환기들은 수용체의 반응점 내 구리원자와의 배위결합으로 인한 비경쟁적 인 저해반응[Neeley 등, 2009]과 반응점 주변의 아미노산 잔기 들 사이의 수소결합으로 인한 경쟁적인 저해반응[Mercedes 등, 2000]에 관여하여 안정한 기질-수용체 착 화합물 "
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