Abstract:
In order to explore the effects of ozone treatment on ascorbic acid-glutathione cycle and cell membrane lipid peroxidation during postharvest storage of prunes, '
France' prunes were used as materials in this experiment, and ozone at 96.3 mg/m
3 was used to treat prunes every 15 days. The fruit was stored at near ice temperature (−1~−1.5 ℃) and relative humidity (80%~90%) for 120 days. Ascorbic acid-glutathione cycle and cell membrane lipid peroxidation related indicators were measured. The results showed that 96.3 mg/m
3 ozone treatment could maintain the contents of ascorbic acid (AsA), glutathione reductase (GR) and glutathione oxidized (GSSG), and reduce the production of dehydroascorbic acid (DHA) during storage. The key enzymes of ascorbic acid metabolism, including ascorbate peroxidase (APX) and monodehydroascorbate reductase (MDHAR), were regulated by ozone treatment. The activities of glutathione reductase (GR) and dehydroascorbate reductase (DHAR) maintained the oxidative balance in cells, and activated the antioxidant metabolic enzyme system, significantly elevating the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) (
P<0.05). It reduced hydrogen peroxide (H
2O
2) content and superoxide anion (O
2−·) production rate, inhibited lipoxygenase (LOX) activity, reduced malondialdehyde (MDA) production, At the end of 120 days of storage, the LOX activity of the 96.3 mg/m
3 ozone treatment group was 32.73% lower than that of the control group, and the MDA content was 14.18% lower than that of the control group (
P<0.05). Therefore, 96.3 mg/m
3 ozone treatment can delay fruit senescence by accelerating the ascorbic acid-glutathione cycle, increasing the activity of antioxidant metabolic enzymes, reducing the damage caused by harmful substances to the cell membrane, so as to maintain the storage quality of prunes and prolong the storage period of prunes.