We investigated the effect of methyl jasmonate (MeJA) on the quality and antioxidant capacity in ‘Xiahui 8’ peach fruit during storage at 20°C and 90–95% relative humidity (RH) for 7 days. Exogenous MeJA maintained better fruit quality during storage, as indicated by reduced weight loss, respiration rate, ethylene production and total soluble solids, as well as maintained appearance and firmness. MeJA treatment significantly improved the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in peach fruit, therefore, reducing the accumulation of superoxide anion (O₂⁻), hydrogen peroxide (H₂O₂) and malondialdehyde (MDA). Additionally, MeJA treatment enhanced the metabolic intensity of AsA-GSH cycle, as key enzyme activities involved in AsA-GSH cycle were markedly increased. These MeJA-promoting effect increased the content of reduced ascorbate (AsA) and glutathione (GSH), and the ratios of reduced to oxidized forms of AsA and GSH, contributing to higher redox status in peach fruit. Collectively, these results suggest that MeJA can maintain better fruit quality and improve antioxidant ability through enhancing AsA-GSH cycle, thus suitable for postharvest application.

我们研究了茉莉酸甲酯 (MeJA) 在 20°C 和 90-95% 相对湿度 (RH) 条件下贮藏 7 天对'夏惠 8' 桃果实品质和抗氧化能力的影响。外源 MeJA 在贮藏过程中保持了更好的果实品质，表现为减重、呼吸速率、乙烯产量和总可溶性固形物减少，并保持外观和硬度。MeJA处理显着提高了桃果实中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和过氧化物酶（POD）的活性，从而减少了超氧阴离子（O ₂ ^-）、过氧化氢（H ₂ O ₂) 和丙二醛 (MDA)。此外，MeJA 处理增强了 AsA-GSH 循环的代谢强度，因为参与 AsA-GSH 循环的关键酶活性显着增加。这些 MeJA 促进作用增加了还原型抗坏血酸 (AsA) 和谷胱甘肽 (GSH) 的含量，以及还原型与氧化型 AsA 和 GSH 的比例，从而提高了桃果实的氧化还原状态。总之，这些结果表明MeJA可以通过增强AsA-GSH循环来保持更好的果实品质并提高抗氧化能力，因此适合采后应用。