Cai Xuanyi, Xiang Wen, Zhao Liangyi, Liu Ziao, Li Ye, Zeng Yuan, Shen Xinyan, Bao Yinqiu, Zheng Yonghua, Jin Peng
College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
Foods. 2025 Jun 26;14(13):2265. doi: 10.3390/foods14132265.
Peach fruit faces severe postharvest losses due to thin epidermis and susceptibility to -induced soft rot. Chemical control risks residue and resistance issues, demanding eco-friendly alternatives. This study elucidated the mechanism by which trans-2-hexenal (E2H) mitigated postharvest soft rot caused by in peach ( cv. Hujing Milu) fruit. The results demonstrated that E2H treatment significantly delayed lesion expansion by 44.7% and disease incidence by 23.9% while effectively maintaining fruit quality by delaying firmness loss, reducing juice leakage, and suppressing malondialdehyde (MDA) accumulation. E2H treatment upregulated phenylpropanoid pathway gene expression, enhancing key phenylpropanoid metabolism enzymes activities (phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), 4-coumarate-CoA ligase (4CL), polyphenol oxidase (PPO), peroxidase (POD)), leading to the increase of total phenolics by 7.9%. E2H treatment analysis revealed significant enhancements in both chitinolytic activity (CHI) and β-1,3-glucanase (GLU) activity by 85.7% and 12.9%, indicating potentiation of the enzymatic defense system. Concurrently, E2H treatment could improve the redox modulation capacity of peach fruits through promoting catalytic efficiency of redox-regulating enzymes, increasing the accumulation of ascorbic acid (AsA) by 8.1%, inhibiting the synthesis of dehydroascorbic acid (DHA) by 18.6%, as well as suppressing the biosynthesis of reactive oxygen species (ROS). These coordinated enhancements in pathogenesis-related proteins (CHI, GLU), phenylpropanoid metabolism activation, and antioxidant systems are strongly associated with E2H-induced resistance against , though contributions from other factors may also be involved.
桃果实由于表皮薄且易受感染引发软腐，采后损失严重。化学防治存在残留和抗性问题，因此需要环保的替代方法。本研究阐明了反-2-己烯醛（E2H）减轻桃（品种：湖景蜜露）果实采后由[具体病原菌未给出]引起的软腐的机制。结果表明，E2H处理显著延缓了病斑扩展44.7%，降低了发病率23.9%，同时通过延缓硬度损失、减少汁液渗漏和抑制丙二醛（MDA）积累有效地保持了果实品质。E2H处理上调了苯丙烷类途径基因表达，增强了关键苯丙烷类代谢酶活性（苯丙氨酸解氨酶（PAL）、肉桂酸4-羟化酶（C4H）、4-香豆酸辅酶A连接酶（4CL）、多酚氧化酶（PPO）、过氧化物酶（POD）），使总酚含量增加了7.9%。E2H处理分析显示，几丁质酶活性（CHI）和β-1,3-葡聚糖酶（GLU）活性分别显著提高了85.7%和12.9%，表明酶促防御系统得到增强。同时，E2H处理可通过提高氧化还原调节酶的催化效率来改善桃果实的氧化还原调节能力，使抗坏血酸（AsA）积累增加8.1%，抑制脱氢抗坏血酸（DHA）合成18.6%，并抑制活性氧（ROS）的生物合成。病程相关蛋白（CHI、GLU）、苯丙烷类代谢激活和抗氧化系统的这些协同增强与E2H诱导的对[具体病原菌未给出]的抗性密切相关，不过可能也涉及其他因素的作用。
