In this paper, the enzymatic characteristics of peroxidase in jun -jujube was studied by spectrophotometric method, using Xinjiang jun-jujube as raw material, In pH 6.0 phosphate buffer solution, 30 %hydrogen peroxide, guaiacol mixture as substrate. The results showed that the optimal temperature was 45 ℃, the optimal pH was 6.8-7.2 and the optimal concentration of substrate was 0.088 2 mol/L. the maximum velocity of POD in Jun Jujube was 49.2 U/min and Km was 0.387 mol/L, the passivation effect was significantly when the temperature is over 55℃,and the POD was passivated completely treated 20 min at 80℃. The passivation of POD by heat treatment fit the first-order kinetics, the ZT was 22.83℃and the Ea was 242.076 kJ/mol.%以新疆骏枣为原料，以pH6.0磷酸缓冲溶液、30%双氧水和愈创木酚的混合液为底物，采用分光光度法研究了红枣中过氧化物酶（POD）的酶学特性及其钝化动力学。结果表明：红枣POD最适温度为45℃，最适pH为6.8~7.2，最适底物浓度为0.0882 mol/L；最大反应速度Vmax=49.2 U/min，Km=0.387 mol/L；当温度大于55℃时，热处理对POD的钝化效果比较显著，80℃处理25 min即可完全钝化红枣POD；热处理对红枣POD的钝化符合一级反应动力学，其ZT=22.83℃，Ea=42.076 kJ/mol。
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