Improvement of chilling tolerance and postharvest quality in mango fruit by pre-storage dopamine application

Mangoes were treated with dopamine (200 μmol L^-1) and stored at 5 °C for 28 days (d). Samples were taken at 7 d intervals and subsequently subjected to 3 d shelf storage at 20 °C to evaluate the effects of dopamine on chilling injury (CI), oxidative stress markers, membrane permeability, lipid peroxidation, antioxidant system activity, γ-aminobutyric acid (GABA) shunt, proline metabolism, and cell wall degradation. Dopamine treatment reduced disease incidence, CI symptoms, oxidative stress, respiration rate, ethylene production, malondialdehyde content, membrane permeability, and degradation of cell wall components. Conversely, treated mangoes exhibited enhanced activities of antioxidant enzymes, elevated levels of proline and its related enzymes, and increased GABA content along with higher activities of its biosynthetic enzymes. In contrast, untreated mangoes showed higher total soluble solids and higher cell wall-degrading enzyme activity, whereas dopamine-treated mangoes maintained higher titratable acidity. In conclusion, dopamine improved chilling tolerance and preserved the postharvest quality of mango.