【摘要】 研究γ-氨基丁酸（γ-aminobutyric acid,GABA）处理对冷藏猕猴桃果实冷害的影响及其与活性氧代谢的关系。采用2.0 mmol/L GABA溶液对采后猕猴桃果实浸泡处理20 min，评价果实在（4±1）℃、相对湿度（85±5）%贮藏条件下的冷害发生情况，并分析果实活性氧产生与清除系统的动态平衡情况。结果表明：与对照组相比，经GABA处理的猕猴桃果实在冷藏过程中冷害指数、细胞膜透性、丙二醛含量、超氧阴离子自由基产生速率和过氧化氢水平上升较缓；超氧化物歧化酶、过氧化氢酶、抗坏血酸过氧化物酶、谷胱甘肽还原酶、单脱氢抗坏血酸还原酶和脱氢抗坏血酸还原酶活力在贮藏前期均有所提高，并且在随后的贮藏期间维持在较高水平，同时果实抗坏血酸和还原型谷胱甘肽含量下降减缓，从而使果实具有较好的抗氧化能力。综上，外源GABA浸泡处理能够通过抑制冷藏猕猴桃果实活性氧积累、提高活性氧清除酶系统和非酶系统活力，维持较好的氧化还原动态平衡，减轻膜脂过氧化反应，维持细胞膜完整性，从而增强果实对低温胁迫的抗性，延缓冷害发生。更多还原

【Abstract】 The effect of γ-aminobutyric acid(GABA) treatment on chilling injury in cold-stored kiwifruit and its relationship with reactive oxygen species(ROS) metabolism were investigated. Postharvest kiwifruit were treated with 2.0 mmol/L GABA solution for 20 min and stored at(4 ± 1) ℃ and(85 ± 5)% relative humidity. Chilling injury development was evaluated and the changes in the dynamic balance between the production and removal of ROS were analyzed. The results showed that compared with the control group, GABA treatment could delay the increases in the chilling injury index, cell membrane permeability and malondialdehyde(MDA) content of cold-stored kiwifruit, inhibit the rate of superoxide anion radical production and the increase in hydrogen peroxide content, and increase and maintain superoxide dismutase(SOD),catalase(CAT), ascorbate peroxidase(APX), glutathione reductase(GR), monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR) activities. Moreover, GABA treatment slowed down the decrease in the contents of ascorbic acid and glutathione, which contributed to higher antioxidant capacity levels in the fruit. The above findings indicated that exogenous GABA treatment could maintain dynamic redox balance, attenuate membrane lipid peroxidation and preserve cell membrane integrity in cold-stored kiwifruit by inhibiting the accumulation of ROS, and increasing the activities of the enzymatic and non-enzymatic ROS systems, thereby enhancing cold stress resistance and ultimately delaying chilling injury.更多还原