山药过氧化物酶的特性及抑制研究

Study on properties and inhibitions of peroxidase from Dioscorea Hemsleyi

以愈创木酚为底物,470nm处测定山药过氧化物酶(POD)的活性,研究了温度、pH、底物浓度、酶浓度、抑制剂和激活剂对其活性的影响。结果表明,山药过氧化物酶的最适反应温度为60℃,最适反应pH为6.0,Km=0.08231mol/L,Vmax=541.518U/(g·min);五种抑制剂对POD的抑制作用由强到弱依次为:VC>L-Cys>NaHSO3>柠檬酸>EDTA,两种激活剂对POD活性的激活作用由强到弱依次为:CuSO4>FeCl3。

Peroxidase（POD） of Dioscorea Hemsleyi was determined spectrophotometrically at 470nm using guaiacol as substrate, and the effect of different temperature, pH, substrate concentration, enzyme concentration, inhibitor and activator on POD were studied.The results showed that the optimum pH and temperature of POD were pH6.0 and 60℃ respectively,and Km = 0.08231mol/L, Vmax = 541.518U/（ g · min）.The order of inhibitors effects on POD was as follows.Vc 〉 L-Cys 〉 NaHSO3 〉 citric acid 〉 EDTA, and the order of activators effects on POD was as follows ：CuSO4 〉 FeCl3.