【摘要】 用丙酮自香蕉皮中提取多酚氧化酶，用氧电极法测得酶促儿茶酚氧化反应的表现活化能为２３．６ｋＪ·ｍｏｌ－１，米氏常数为１．５８×１０－２ｍｏｌ／Ｌ，测试了９种化合物对酶活性的抑制效果。以苯甲酸为抑制剂研究了抑制动力学及机理，测出蕉皮酚酶中含有铜离子，它起着活化反应物的作用，抑制剂与铜离子的结合抑制了酶的催化活性。更多还原

【Abstract】 The polyphenoloxidase has been isolated from banana peel by extraction with coldacetone. The catechol oxidation reaction catalyzed by polyphenoloxidase is selected as a mod-el to study the oxidase catalyzed oxidation by using an oxygen electrode,The activation ener-gy of the reaction was calculated to be 23. 6kJ· mol￣(-1),and the Michae’s constant 1· 58×10￣(-2) mol/L. Nine compounds were found to have inhibition effects on the activity of the oxi-dase,The inhibition kinetics and the mechanism of the catechol oxidation have been investi-gated by using benzoic acid as inhibitor. The results showed that the copper ions which wasfound in the polyphenoloxidase may activate the substrates and the combination of the copperions with inhibitor results in the inhibition effect on the catalytic oxidation.更多还原