Bamboo leaf extract treatment alleviates the surface browning of fresh-cut apple by regulating membrane lipid metabolism and antioxidant properties

BACKGROUNDThe effect of bamboo leaf extract (BLE) on controlling the browning of fresh-cut apple stored at 4 degrees C was investigated. Browning index, H2O2 content, O2- production rate, malondialdehyde (MDA) contents, total phenolic content (TPC) and soluble quinone content (SQC), the activities of polyphenol oxidase (PPO), peroxidase (POD), lipoxygenase (LOX), superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), DPPH (2,2-diphenyl-2-picryl-hydrazyl) and ABTS [2,2-azinobis(3-ethylbenzothiazoline- 6-sulfonic acid)] radical scavenging activities, and the expression of genes related to browning were all investigated.RESULTSBLE effectively alleviated the surface browning of fresh-cut apple, accompanied by a reduction in SQC, LOX activity, H2O2, O2- production rate and MDA accumulation. Furthermore, BLE treatment enhanced the TPC, enzymatic (SOD, CAT, APX and POD) and non-enzymatic antioxidant activities. Principal component analysis and Pearson correlation analysis found the browning inhibition by BLE is not through the reduction of phenolic substrates and PPO activity.CONCLUSIONBLE controls the browning of fresh-cut apple by increasing the antioxidant capacity to scavenge ROS, which could alleviate oxidative damage and maintain the membrane integrity. (c) 2023 Society of Chemical Industry.