Changes in abscisic acid, antioxidant concentration and the activities of antioxidant enzymes in Japanese apricot (Prunus mume) under short-term anoxic storage conditions

Application of an anoxic treatment is used as a chemical free and environmentally friendly technique to delay ripening, eliminate physiological disorders, promote antioxidant capacity and extent storage shelf-life of some fruits and vegetables. The effects of an anoxic treatment on lipid peroxidation, abscisic acid (ABA) concentration, antioxidant activity, and the activities of selected antioxidant enzymes in Japanese apricot (Prunus mume) were evaluated. In the anoxic treatment used in this study, mature green fruit were exposed to N₂ with a flow rate 200-250 mL min^‑1 for 6 h at 20°C. Non-treated fruit were used as a control treatment. Fruit were kept in corrugated boxes and subsequently stored at 20°C and 90-95% RH. They were randomly collected every two days for analysis. The anoxic treatment delayed changes in fruit color, induced 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, and ferric reducing antioxidant power (FRAP), and increased total phenolic concentrations (TPC). The anoxic treatment moderated the integrity of fruit membranes by delaying malondialdehyde (MDA) accumulation, increasing ABA concentrations, delaying the decline of superoxide dismutase (SOD) and catalase (CAT) activity, and promoting peroxidase (POD) activity. The results suggest that an anoxic treatment may delay the ripening processes in Japanese apricot by promoting the activities of antioxidants and the levels of antioxidant enzymes.