SummaryMelatonin (MT), a natural signalling compound derived from tryptophan, has gained significant attention for delaying postharvest ripening and senescence in various fruits and vegetables. In the present study, the effect of MT treatment was evaluated on the postharvest shelf‐life of bell pepper. Fruits were dipped in various MT concentrations (70, 120, 170, 220 μmol L−1) for 20 min and stored at 10 ± 1 °C for 20 days. The bell pepper treated with 120 μmol L−1 MT significantly suppressed respiration, weight loss and delayed chlorophyll degradation. Additionally, MT (120 μmol L−1) treatment reduced loss of firmness, titratable acidity and retained total phenol, flavonoid and ascorbic acid content. It hindered malondialdehyde accumulation by enhanced DPPH radical scavenging and antioxidant enzyme activity like superoxide dismutase, catalase and peroxidase, over the control. Conclusively, 120 μmol L−1 MT prolongs the postharvest shelf‐life of bell pepper by 20 days with superior sensory quality, surpassing the control by 10 days. Therefore, MT treatment is a commercially useful technology for maintaining quality and prolonging the postharvest shelf‐life of bell pepper.

中文翻译：

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褪黑素处理可增强灯笼椒 (Capsicum annuum L.) 冷藏期间生物活性化合物的保留、抗氧化活性和保质期

摘要褪黑激素 (MT) 是一种源自色氨酸的天然信号化合物，因延迟各种水果和蔬菜采后成熟和衰老而受到广泛关注。在本研究中，评估了 MT 处理对甜椒采后保质期的影响。将水果浸入不同浓度的 MT（70、120、170、220 μmol·L−1) 20 分钟并在 10 ± 1 °C 下保存 20 天。 120 μmol·L处理的灯笼椒−1MT 显着抑制呼吸、体重减轻并延迟叶绿素降解。此外，MT（120 μmol·L−1) 处理减少了硬度、可滴定酸度的损失，并保留了总酚、类黄酮和抗坏血酸含量。它通过增强 DPPH 自由基清除能力和超氧化物歧化酶、过氧化氢酶和过氧化物酶等抗氧化酶活性来抑制丙二醛的积累。最终，120 μmol·L−1MT 使甜椒的采后保质期延长了 20 天，且感官品质优异，比对照提高了 10 天。因此，MT 处理是一项具有商业用途的技术，可用于保持甜椒的质量并延长采后保质期。