草酸处理对杧果采后果实AsA-GSH循环系统的影响

Effects of Oxalic Acid Treatment on AsA-GSH Cycle in Mango Fruit During Storage at Room Temperature

杧果(Mangifera indicaL.)栽培品种‘圣心’采前套袋果实采后经5mmol·L-1草酸溶液浸泡10min后常温(25℃)下贮藏,期间果实硬度系数、病情指数、腐烂率、黄化都显著低于对照;其中,处理果实果皮的还原型抗坏血酸(AsA)和还原型谷胱甘肽(GSH)含量保持较高,抗坏血酸氧化酶(APX)和谷胱甘肽还原酶(GR)活性在贮藏9d后提高,同时,超氧阴离子()生成速率、过氧化氢(H2O2)含量和丙二醛(MDA)含量降低,说明草酸处理可通过提高果皮AsA-GSH循环系统中抗氧化酶活性和抗氧化剂水平来增强清除活性氧自由基(ROS)能力,减轻膜脂过氧化伤害,进而有利于延缓套袋杧果采后成熟衰老进程,提高果实的商品率。

Pre-harvest bagging mango fruit（Mangifera indica L.＇Shengxin＇）were dipped in 5 mmol · L-1 oxalic acid solution for 10 min after harvested and then stored at room temperatur（e25 ℃）.The results showed that,as compared to control fruit,higher firmness index,lower disease index and decay incidence,and decreaed yellowing were observed in treated fruit.In addition,higher levels of ascorbate acid（AsA）and glutathione（GSH）,and activation of enzymatic activities such as ascorbate peroxidase（APX）and glutathionereductase（GR）,and decreases in radical oxygen species（ROS）production（including superoxide, and hydrogen peroxide,H2O2）and malondialdehyde（MDA）content were also presented in the peel of treated fruit during storage.It was suggested that the physiological effects of oxalic acid,in increasing activity of antioxidant enzyme and in elevating level of antioxidant involved in AsA-GSH cycle,could be beneficial in delaying ripening process of bagging mango fruit during storage,and pre-storage application of oxalic acid could be a promising method to suppress postharvest deterioration and extend useful shelf-life of the bagging mango fruit.