Inhibitory effects on mushroom tyrosinase by some alkylbenzaldehydes.
The inhibition kinetics on the diphenolase activity of mushroom tyrosinase by some alkylbenzaldehydes has been investigated. The results show that the alkylbenzaldehydes assayed can lead to reversible inhibition to the enzyme; o-tolualdehyde and m-tolualdehyde are mixed-type inhibitors and p-alkylbenzaldehydes are uncompetitive inhibitors. For the p-alkylbenzaldehydes, the inhibition potency follows the order: p-tolualdehyde < p-ethylbenzaldehyde < p-propylbenzaldehyde = p-Isopropylbenzaldehyde < p-tert-butylbenzaldehyde = p-butylbenzaldehyde < p-pentylbenzaldehyde < p-hexylbenzaldehyde > p-heptylbenzaldehyde > p-octylbenzaldehyde, indicating the hydrophobic p-alkyl group played an important role in inhibition to the enzyme. The inhibitory effects of alkylbenzaldehydes on the monophenolase activity have also been studied. The results show that o-tolualdehyde and m-tolualdehyde can lengthen the lag time and decrease the steady-state activity of the enzyme, but p-alkylbenzaldehydes only decrease the steady-state activity and do not lengthen the lag time, indicating that their inhibitory mechanisms are different.
The Key Laboratory of Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen 361005, People's Republic of China. chenqx@jingxian.xmu.edu.cn
Qing-Xi
QX
Chen
Kang-Kang
KK
Song
Qin
Q
Wang
Huang
H
Huang
D000363:Agaricales / Q000201:enzymology*; D001547:Benzaldehydes / Q000378:metabolism / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000378:metabolism / Q000494:pharmacology*; D007700:Kinetics; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010088:Oxidoreductases / Q000037:antagonists & inhibitors
D001547:Benzaldehydes; D004791:Enzyme Inhibitors; D010088:Oxidoreductases; C412191:monophenolase; D014442:Monophenol Monooxygenase; C093384:2-methylbenzaldehyde