冬枣果实过氧化物酶酶学特性分析  

Characteristics of peroxidase from Zizyphus jujuba Mill

作　　者：丁薪源[1] 周娜娜[1] 赵玉梅[1] 曹建康[1] 

机构地区：[1]中国农业大学食品科学与营养工程学院,北京100083

出　　处：《食品科技》2012年第4期31-34,39,共5页Food Science and Technology

基　　金：国家自然科学基金项目(31071625)

摘　　要：以冬枣(Zizyphus jujuba Mill.)果实为材料,研究了枣果实过氧化物酶(Peroxidase,POD)的酶学特性,并探讨了不同抑制剂和激活剂对POD活性的影响,为冬枣的加工与贮藏等过程中防止酶促褐变提供参考和理论依据。结果表明:冬枣枣皮POD活性是枣肉POD活性的10倍,枣果实POD的最适反应温度为40℃,最佳反应底物(愈创木酚)浓度为0.0002mol/L,最大反应速度为Vmax=2.86U/min,米氏常数Km=0.2516mol/L。在0～2.0mmol/L浓度范围内,抑制剂对POD抑制作用为:抗坏血酸>L-半胱氨酸>柠檬酸>EDTA。在0～20.0mmol/L浓度范围内,激活剂对POD激活作用为:FeCl3>CuCl2>吐温-20。Characteristic and inhibition of peroxidase（POD） from Zizyphus jujuba Mill were studied.Provide reference and theoretical basis to protect Zizyphus jujuba Mill from enzymatic browning in the course of processing and storage.The result showed that the activity of POD in the peel was 10 times higher than that in the pulp of the jujube.The optimum temperature was identified to 40 ℃.The optimum concentration of the reaction substrate（guaiacol） is 0.0002 mol/L.The reaction kinetic of enzyme was Michaelis Equation model.Using guaiacol as substrate,Vmax were 2.86 U/min and Km were 0.2516 mol/L,respectively.In the concentration range of 0～2.0 mmol/L,POD activities were inhibited by the following inhibitors：Vc,L-cys,citrate,EDTA.In the concentration range of 0～20.0 mmol/L,POD activities were stimulated by the following activators：FeCl 3,CuCl 2,Tween-20.

关 键 词：冬枣 酶学特性 过氧化物酶 

分 类 号：TS201.25[轻工技术与工程—食品科学]