Effects of nitric oxide on reactive oxygen species and antioxidant capacity in Chinese Bayberry during storage

Chinese bayberry fruit were fumigated with 20 mu ll(-1) NO for 2 h at 20 degrees C,then stored at 1 +/- 0.5 degrees C and 90% relative humidity for 10 days. Postharvest disease incidence, ethylene production, fruit firmness, membrane permeability, lipid peroxidation, H2O2 contents, rate of superoxide anion (O-2(center dot-)) production, antioxidant enzymes activities, and antioxidant ability were determined after storage. The results showed that fumigation with NO inhibits ethylene production and disease incidence, and delay the decrease in firmness, total phenolics contents and DPPH radical-scavenging activity in Chinese bayberry fruits. NO treatment reduced the increases in membrane permeability and lipid peroxidation, delayed the increases in both the rate of O-2(center dot-) production and H2O2 contents, and increased activities of SOD, CAT and APX. These results indicate that NO might maintain the balance between the formation and detoxification of ROS, enhance the resistance of tissues to decay and preserve better quality of Chinese bayberries. (C) 2012 Elsevier B.V. All rights reserved.