Study on the mechanism of browning inhibited by methyl jasmonate treatment on fresh-cut pear

In order to develop new methods in keeping fruits and vegetables fresheness, effects of different concentrations of methyl jasmonate treatment on enzymatic browning of fresh-cut crystal pear during room temperature storage were investigated. The results showed that the relative conductivity increased rapidly, the content of polyphenol and the activity of polyphenol oxidase (PPO) increased then formed enzymatic browning showed the L* value decreasing gradually in pear after cutting, and the damage from cutting aggravated membrane lipid peroxidation, and induced the activity of peroxidase (POD) , superoxide dismutase (SOD) , catalase (CAT) to remove excess free radicals for increasing the stress resistance of the fruit. Methyl jasmonate treatment protected the cell membranes, inhibited the leakage of phenolic compounds and PPO activity, weaken the trend of enzymatic browning;and it delayed the rising of POD, SOD, CAT activity in order to maintain longer time the capacity of scavenging free radical thus postponed the membrane lipid peroxidation process. Especially, 1μmol/L methyl jasmonate treatment was more effective in maintaining the storage quality of fresh-cut pears and delaying the aging of fresh-cut pear.