果实成熟衰老与保护酶系统的关系

Relationship Between Ripening and Senescence of Fruits and Antioxidase

果实成熟衰老与活性氧代谢和膜脂过氧化作用有关。自由基清除剂中ＳＯＤ、ＰＯＤ、ＣＡＴ等保护酶系统可以有效地清除活性氧、自由基，保持体内活性氧的平衡，降低膜脂过氧化作用和ＭＤＡ积累量。ＳＯＤ、ＰＯＤ、ＣＡＴ等酶活性的高低可以作为判定果实耐藏性大小的指标和果实成熟衰老的标志。在贮藏过程中，果实的ＳＯＤ、ＰＯＤ、ＣＡＴ活性会发生变化，且在不同种类果实中表现出不同趋势。贮藏温度、气体指标等贮藏条件和振动胁迫、冷激、热激、涂膜等处理会影响到ＳＯＤ、ＰＯＤ、ＣＡＴ活性的大小，从而影响果实的成熟衰老进程。

The senescence of fruit is related to the active oxygen metabolism and membrane lipid peroxidation. Active oxygen and free radicals are effectively cleared away by some scavengers of free radicals-SOD,POD and CAT,while maintain the balance of active oxygen in fruit and decrease membrane lipid peroxidation and MDA accumulation contents.Activities of SOD,POD,CAT are seemed as the indices deciding the storage life of fruit and the marks of fruit ripening.During storage periods,the activities of SOD,POD and CAT cause to change as well as show different tendency among the different varieties. The activities of SOD,POD and CAT are influenced by storage temperatures,gas conditions,vibration stress,cold shock,heat shock and coating treatments, thereby, influence the process of ripening and senescence in fruit.