Given the increasing demand for fruit safety assurance and environmental protection, plant essential oils have gained significant attention as natural alternatives for control of postharvest decay caused by various pathogens. In postharvest management, it is particularly important to effectively control postharvest decay without compromising the quality attributes of fruits. Although oregano essential oil (OEO) has been extensively studied for its antimicrobial properties against various postharvest pathogens, few studies have focused on its interactions with postharvest fruits. In this study, OEO was applied for management of postharvest decay of Pyrus sinkiangensis caused by Penicillium expansum, and its antifungal mechanisms and impacts on the quality attributes of pears were investigated. The OEO exhibited notable inhibitory effects, with determined MIC (0.02%) and MFC (0.04%) against P. expansum, which highlighted its potential as a viable alternative to synthetic fungicides. Our findings revealed that OEO disrupted P. expansum by compromising the integrity of the fungal plasma membrane, as evidenced by changes in plasma membrane permeability and the leakage of cellular components. The OEO treatment significantly reduced weight loss, maintained firmness, and preserved soluble-solid content in the treated pears. In addition, OEO treatment stimulated the intrinsic antioxidant mechanisms of pears, as demonstrated by elevated activities of superoxide dismutase and catalase during storage. This study provides compelling evidence for the antifungal and quality-preserving properties of OEO in the postharvest management of pears, underscoring its potential as an alternative to synthetic fungicides for controlling postharvest decay. The elucidation of the interaction between OEO and P. sinkiangensis would greatly enhance our comprehensive understanding of the biological activities of OEO and facilitate its practical application in the postharvest management of pears.

In response to the growing need for sustainable and safe postharvest strategies, plant essential oils have emerged as promising natural alternatives to synthetic fungicides. Mango (Mangifera indica L.), as a vital tropical fruit, suffers significant postharvest losses due to anthracnose caused by Colletotrichum gloeosporioides. This study investigated the antifungal efficacy of oregano essential oil (OEO) against C. gloeosporioides and its regulatory effects on the postharvest quality of mango fruit. The potent antifungal activity of OEO is demonstrated by its low MIC (0.005%) and MFC (0.01%) against C. gloeosporioides. The antifungal mechanism was primarily attributed to the disruption of plasma membrane integrity of C. gloeosporioides, as indicated by increased propidium iodide uptake, elevated extracellular conductivity, and leakage of cellular proteins. The OEO treatment inhibited peel color transformation, reduced weight loss, maintained firmness, and slowed the increase in the soluble solids content to acidity ratio. Furthermore, OEO enhanced the fruit’s antioxidant capacity by sustaining higher superoxide dismutase activity and suppressing the activities of polyphenol oxidase and peroxidase, leading to a marked reduction in malondialdehyde accumulation. These findings comprehensively demonstrate the dual functionality of OEO as a direct fungicidal agent and a systemic physiological regulator that delays senescence and preserves mango quality. This study underscores the potential of OEO as a sustainable alternative for integrated postharvest management of mango anthracnose, offering insights for its practical application in the fruit industry.