黑豆过氧化物酶的酶学特性研究

Study on properties of peroxidase in blackbean

试验用磷酸缓冲液提取黑豆中的过氧化物酶(POD),并对其进行酶学特性研究。结果表明,POD在磷酸盐缓冲液中最适pH为5.0,最适反应温度为30℃;用Lineweaver-Burk法进行双倒数作图,POD对愈创木酚和过氧化氢的表观Km值分别为0.49 mmol/L和0.62 mmol/L;在供试浓度范围内,Cu2+可激活POD酶活性,Mg2+、Al3+、K+、Na+对酶活性有抑制作用,而抗坏血酸(维生素C)、柠檬酸、乙二胺四乙酸(EDTA)、乙二胺四乙酸二钠(EDTA-Na2)均是黑豆POD的抑制剂。

Peroxidase （POD）in blackbean was extracted by phosphate buffer, and the properties of POD were studied. The results showed that：the optimum pH of POD was 5.0 in phosphate buffer,and the optimum temperature was 30 ℃.By the Lineweaver-Burk plot,the apparant Km values of 4-methylcatechol and H202 were 0.49 mmol/L and 0.62 mmol/L, respectively. Under different concentration, Cu^2＋ was the activator of POD,while Mg^2＋、Al^3＋、K＋、Na＋ were the inhibitors of POD.And the results also showed that vitamin C, citric acid, EDTA and EDTA-Na2 were the inhibitors of POD.