Low temperature mitigates mango quality deterioration by improving antioxidant ability and gene expression levels

Mango (Mangifera indica) is a tropical, climacteric fruit with unique flavor and rich nutrition, but its postharvest shelf life is limited due to softening, rotting, and cold damage susceptibility. Recent research indicates that storage at 12 °C can preserve mango fruit well, but the underlying preservation mechanism remains poorly understood. In this study, postharvest quality changes and antioxidant mechanism of 'Tainong No.1' mango stored at 12 and 30 °C with 90% ± 5% RH for 24 d were explored. The results showed that, compared with storage at 30 °C, storage at 12 °C significantly maintained fruit firmness, while reducing weight loss rate and malondialdehyde (MDA) content. Better cell morphology and delayed starch degradation were found at 12 °C through microscopic analysis. Moreover, the mango fruit stored at 12 °C showed significantly enhanced activities of antioxidant enzymes, including peroxidase (POD), superoxide dismutase (SOD), phenylalanine ammonia lyase (PAL), and ascorbate peroxidase (APX). Induced expressions of enzyme genes supported the corresponding enhanced enzyme activities. Furthermore, correlation analysis demonstrated that SOD, total phenols, and flavonoids might have a greater contribution to balancing the ROS homeostasis of postharvest mangoes. These findings suggest that storage at 12 °C might maintain mango quality and prolong the storage period by regulating fruit antioxidant capacity.