Inhibitory Effect of Ferulic Acid on Oxidation of L-DOPA Catalyzed by Mushroom Tyrosinase

The inhibitory effect of ferulic acid on the diphenolase activity of mushroom tyrosinase and the kinetic behavior were studied with L-3,4-dihydroxyphenylalanine （L-DOPA） as substrate. The inhibitor concentration leading to 50% relative activity lost （IC50） was estimated to be 0.15 mmol·L^-1. The inhibition mechanism obtained from Lineweaver-Burk plots shows that ferulic acid is a competitive inhibitor and the inhibition of tyrosinase by ferulic acid is a reversible reaction. The equilibrium constant for ferulic acid binding with the tyrosinase was determined to be 0.25 mmol·L^-1 for diphenolase. Keywords tyrosinase, ferulic acid, kinetics, inhibition, L-DOPA, diphenolase

在 mushroomtyrosinase 和运动行为的 diphenolase 活动的 ferulic 的禁止的效果作为底层与 L-3,4-dihydroxyphenylalanine (L-DOPA ) 被学习。导致失去的 50% 相对活度(IC_(50 )) 的禁止者集中被估计是 0.15mmol · L ^(-1) 。从 Lineweaver-Burk 阴谋获得的抑制机制证明 thatferulic 酸是竞争性抑制物，由 ferulic 的 tyrosinase 的抑制是可逆反应。为与 tyrosinase 有约束力的 ferulic 的平衡常数决心是 0.25mmol · L ^( 为 diphenolase 的 -1) 。