The Effects of Hot Water, 1-Methylcyclopropene and Calcium Chloride Treatment on Antioxidant Enzyme Activities of Cherry Laurel (Prunus Laurocerasus L.) Fruits

Cherry laurel metabolism continues actively after harvest, but quality deterioration is exacerbated by the accumulation of reactive oxygen species (ROS). Hot water (HW), 1-methylcyclopropene (1-MCP) and calcium chloride (CaCl2) have a significant effect on attenuating the postharvest metabolism of vegetables and fruits. This research aimed to evaluate the ROS scavenging effect of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), ascorbate peroxidase (APX), glutathione peroxidase (GPX) and dehydroascorbate reductase (DHAR) activities in cherry laurel fruits of postharvest HW (45, 50, and 55 & DEG;C), 1-MCP (0.5, 1, and 5 & mu;L L-1) and CaCl2 (1 and 2%) treatments. The results indicated that compared to the control cherry laurel fruits treated with HW, 1-MCP and CaCl2 fruits maintained higher levels of activities of SOD, CAT, GR, APX and DHAR at the end of storage (30 days), but exhibited lower SOD, CAT, GR, APX and GPX up to 20 days. The decrease in antioxidant enzyme activity during 20 days of cold storage after all treatment periods is due to the inhibition of ROS synthesis, which maintains cell integrity and stability. Correlation analysis revealed that the change in SOD activity was associated with CAT, APX and GPX. In conclusion, HW, 1-MCP, and CaCl2 treatments all inhibited ROS production until day 20 of cold storage and delayed postharvest quality deterioration in cherry laurel by increasing the activities of antioxidant enzymes on day 30 of storage. CaCl2 could be used in cherry laurel to extend shelf-life and improve commercial quality because it is simple and cost-effective.