一氧化氮对采后李果实线粒体膜氧化损伤的影响

【目的】研究一氧化氮(NO)对采后李果实线粒体膜氧化伤害的影响。【方法】分别用0、10、15、30μL.L-1NO处理李果实,测定25℃贮藏13d内果实呼吸速率、活性氧(ROS)含量、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)的活性、线粒体通透性转换孔开放程度、膜电位、膜流动性、细胞色素(Cyt)c/a的变化。【结果】与对照和其它NO处理相比,15μL.L-1NO提高了果实中SOD、CAT和POD活性,有效减少了果实中氢过氧化物和超氧阴离子自由基等ROS的含量,抑制了线粒体通透性转换孔的开放,延缓了线粒体膜通透性的升高和Cytc的释放,维持了较高的膜电位。随着浓度升高,30μL.L-1NO对线粒体膜的保护作用降低。【结论】15μL.L-1NO有效减轻了ROS对李果实线粒体膜的氧化伤害,保护线粒体膜的完整性。

Effect of NO on Oxidative Damage to Mitochondrial Membrane in Harvested Plum Fruit

【Objective】 This paper aimed to study the effects of nitric oxide (NO) on oxidative damage by reactive oxygen species (ROS) to mitochondrial membrane in harvested plum fruit (Prunus salicina Lindl.). 【Method】 The plum fruits were fumigated with 0, 10, 15 and 30 μL?L-1 NO gas and then stored for 13 days at 25℃. The physiological and biochemical properties, including respiration, contents of hydroperoxide and superoxide radical, activities of superoxidase (SOD), catalase (CAT) and peroxidase (POD), the opening of mitochondrial permeability transition pores, electric potential and cytochrome c/a were determined. 【Result】 Compared with the control and treatment with 10 or 30 μL?L-1 NO, treatment with 15 μL?L-1 NO increased the activities of SOD, CAT and POD, decreased effectively the contents of hydroperoxides and superoxide radical, inhibited the opening of mitochondrial permeability transition pores, delayed the increase of mitochondrial permeability and Cyt c/a, maintained high electric potential. With high concentration of NO, the protection by treatment with 30 μL?L-1 NO reduced. 【Conclusion】 Application of 15 μL?L-1 NO can effectively alleviate oxidative damage by ROS to mitochondrial membrane in harvested plum fruits, protect the integrity of mitochondrial membrane.