不同品种皱皮木瓜过氧化物酶特性的比较研究

Study on the characterization of POD from different cultivars of Chaenomeles spiciosa(Sweet) Nakai

摘要: 以不同品种的皱皮木瓜为原料,用Tris-HCl缓冲液提取过氧化物酶（POD）,以愈创木酚-H2O2为底物,采用比色法对3个品种的皱皮木瓜POD酶学性质进行了比较研究。结果显示,品种YATS 066（A）、YATS153（B）、YATS251（C）的POD最适温度分别为20、25、30℃,都在20℃以内能较好的保持活性。三个品种的POD都有两个最适p H,p H稳定性范围分别在7.5⁹、3⁶、3.5⁷。金属离子对A、B的影响基本相同。对三个品种的抑制能力最强的抑制剂是SDS,其次为抗坏血酸。

Abstract: The peroxidase was isolated from Chaenomeles spiciosa( Sweet) Nakai by Tris- HCl buffer.With guaiacol- H2O2 as substrate,the enzyme characterization of three Chaenomeles spiciosa( Sweet) Nakai cultivars was monitored by measuring the absorbance.In YATS 066( A),YATS153( B),YATS251( C),the results showed that the optimum temperature for POD activity were respectively 20,25,30℃.The POD of all cultivars could keep stabilized under 20℃.The peroxidases of three cultivars all had two optimum p H.And the p H stability range was at p H7.5~9,p H3~6,p H3.5~7.Metal ions had the same effects on the POD activity of A,B and C.The optimum inhibitor of POD activity in all three Chaenomeles spiciosa( Sweet) Nakai cultivars was SDS,and then followed by ascorbic acid.