猕猴桃衰老过程中PG、果胶质和细胞壁超微结构的变化

Changes of Polygalacturonase, Pectin and Ultrastructure of Cell Wall in Kiwifruit during Senescence

采后美味猕猴桃秦美果肉组织乙烯生成不断增加的同时,PG(多聚半乳糖醛酸酶)活性迅速提高,致使原果胶大量降解为可溶性果胶,细胞结构受损,胞壁纤维松弛、细胞器逐步空泡化,果肉由硬变软。PG活性和果肉硬度的变化呈明显的负相关。

This paper studied the changes of polygalacturonase (PG) activity, pectin contents in kiwifruit ( Actinidia deliciosa C. F Liang et A. R. Ferguson, cv. Qinmei) and the ultrastructure of the cell wall. The results indicated that ethylene production of kiwifruit gradually increased after picking, at the same time PG activity rised quickly. The protopectin content of the fruit decreased and soluble pectin content of the fruit increased. Then fiber of the cell wall relaxed, followed by the gradual disappearance of the cell organelles. At last, the flesh firmness of kiwifruit decreased. There was a negative correlation between the PG activity and the firmness of fruit.