Abstract Melatonin reportedly delays postharvest fruit senescence, but information on its in vivo effects on pesticide degradation in postharvest fruit is limited. In this study, we investigated the effect of melatonin on the regulation of pesticide degradation and antioxidant nutrient accumulation in jujube fruit after storage. The results showed that melatonin treatment markedly promoted the degradation of three different types of pesticide (chlorothalonil, malathion, and glyphosate) in postharvest jujube fruit. However, this melatonin-enhanced pesticide degradation was greatly reduced by p-chlorophenylalanine (a specific inhibitor of melatonin synthesis) and l -buthionine-sulfoximine (a specific inhibitor of glutathione). Furthermore, pesticide-induced glutathione and melatonin accumulation, coupled with increased glutathione reductase and glutathione S-transferase activities, was further enhanced by melatonin in jujube fruit after storage. Pesticide-delayed fruit senescence (evaluated by weight loss, decay incidence, and firmness) was also further enhanced by melatonin. Interestingly, pesticide-impaired ascorbic acid contents, total phenolics accumulation, and total antioxidant capacities (as evaluated by Fe3+ reducing power) recovered with melatonin treatment in postharvest jujube fruit. This study provides a new biodegradable method for pesticide removal and improves postharvest fruit quality in agronomic production.

中文翻译：

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褪黑素减少农药残留，延缓衰老，提高采后枣果实抗氧化营养积累

摘要 据报道，褪黑激素会延迟果实采后衰老，但关于其对采后果实中农药降解的体内影响的信息有限。在本研究中，我们研究了褪黑激素对贮藏后枣果中农药降解和抗氧化养分积累的调节作用。结果表明，褪黑素处理显着促进了采后枣果实中三种不同类型农药（百菌清、马拉硫磷和草甘膦）的降解。然而，对氯苯丙氨酸（褪黑激素合成的特异性抑制剂）和 l-丁硫氨酸-亚砜亚胺（谷胱甘肽的特异性抑制剂）大大减少了这种褪黑激素增强的农药降解。此外，农药引起的谷胱甘肽和褪黑激素的积累，再加上谷胱甘肽还原酶和谷胱甘肽S-转移酶活性的增加，贮藏后枣果实中的褪黑激素进一步增强。褪黑激素还进一步增强了农药延迟的果实衰老（通过体重减轻、腐烂发生率和硬度进行评估）。有趣的是，在采后枣果实中，用褪黑激素处理后，农药受损的抗坏血酸含量、总酚类物质积累和总抗氧化能力（通过 Fe3+ 还原能力评估）得以恢复。该研究为农药去除提供了一种新的可生物降解方法，并在农艺生产中提高了果实采后质量。和坚定）也进一步增强了褪黑激素。有趣的是，在采后枣果实中，用褪黑激素处理后，农药受损的抗坏血酸含量、总酚类物质积累和总抗氧化能力（通过 Fe3+ 还原能力评估）得以恢复。该研究为农药去除提供了一种新的可生物降解方法，并在农艺生产中提高了果实采后质量。和坚定）也进一步增强了褪黑激素。有趣的是，在采后枣果实中，用褪黑激素处理后，农药受损的抗坏血酸含量、总酚类物质积累和总抗氧化能力（通过 Fe3+ 还原能力评估）得以恢复。该研究为农药去除提供了一种新的可生物降解方法，并在农艺生产中提高了果实采后质量。