暗诱导绿豆叶片衰老期间多酚氧化酶、过氧化物酶和过氧化氢酶活性的变化

CHANGES IN THE ACTIVITIES OF POLYPHENOLOXIDASE, PEROXIDASE AND CATALASE DURING THE DARK INDUCED SENESCENCE OF MUNG BEAN LEAVES

绿豆(PhaseolusraditusL.)五日龄连体叶片暗诱导衰老过程中,叶绿素和可溶性蛋白含量分别干暗培养的第2和第3天开始降低,多酚氧化酶、过氧化物酶和过氧化氢酶活性在衰老起始后明显增加。黑暗培养7天,多酚氧化酶和过氧化氢酶活性增加了2倍,过氧化物酶活性增加了5倍左右。衰老叶片的总酚含量则相应减少。本文对以上酶活性的变化与衰老的关系进行了讨论。

During the senescence of attached leaves of 5-day-old mung bean (Phaseolus raditus L. ) seedlings induced in dark , the contents of chlorophyll and soluble protein started to decline after kept in dark for 2 and 3 days repectively. Simultaneously, the activities of polyphenoloxidase, peroxidase and catalase markedly enhanced in company with a slow decrease in the level of total phenolics. Remaining in dark for 7 days increased the activities of polyphenoloxidase and peroxidase by 2 folds,and even 5 folds for catalase. The leaves remaining under light showed no significant increase in the activities of those enzymes , but a slow accumulation of total phenolics. The relationship between the changes in those enzyme activities and leaf senescence was discussed.