A novel mitigator of enzymatic browning--hawthorn leaf extract and its application in the preservation of fresh-cut potatoes

Objectives:The purpose of this study was to evaluate the antibrowning functions of hawthorn leaf extract on fresh-cut potato and its possible mechanism.Materials and Methods:Fresh-cut potatoes were treated with different concentrations(0.01%,0.05%,and 0.1%)of hawthorn leaf extract and preserved at 4 C for 8 days.The appears nee and colour of potato slices were evaluated,along with the content of the phenol,malondialdehyde(MDA),and hydrogen peroxide(H2O2)during cold storage.Meanwhile,the activities of polyphenol oxidase(PPO),peroxidase(POD),phenylalanine ammonia-lyase(PAL),lipoxygenase(LOX),catalase(CAT),superoxide dismutase(SOD),and the antioxidant capacity were determ in ed.Furthermore,the composition of hawthorn leaf extract was analyzed by high-performance liquid chromatographytandem mass spectrometry(HPLC-MS/MS).Results:The addition of hawthorn leaf extract effectively delayed the browning process.It not only enhanced the CAT activity and antioxidant capacity but also reduced the LOX activity and accumulation of MDA and H_(2)O_(2).Meanwhile,the activities of PPO,POD,and PAL as well as the content of phe nol were con trolled.Additionally,25 phe nols,34 flavonoids,and 5 proa nthocya nidins were identified through high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS),ideluding caffeic acid,quercetin and catechol.Conelusion:Hawthorn leaf extract significantly alleviated the browning of fresh-cut potato.It could serve as a n atural an tibrowning alter native by stabilizing the membra ne and modulating reactive oxygen species and redox reactions.