Identification and characterization of antioxidant peptides from Chinese dry-cured mutton ham

BACKGROUND Chinese mutton ham is a dry-cured meat product with a long ripening time. The aim of this study was to identify and characterize antioxidant peptides from Chinese mutton ham. RESULTS Mutton ham peptides (MHPs) were purified by gel filtration, anion exchange and reversed-phase high-performance liquid chromatography steps. The 2,2 '-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) free radical scavenging capacity was used to guide the purification of MHPs. Three antioxidant peptides were identified by liquid chromatography with tandem mass spectrometry (LC-MS/MS) as Met-Trp-Thr-Asp (MWTD), Ala-Pro-Tyr-Met-Met (APYMM) and Phe-Trp-Ile-Ile-Glu (FWIIE), with molecular weights 551.61, 611.76, and 706.84 Da, respectively. Among them, APYMM exhibited the highest ABTS radical scavenging activity. The three peptides had the ability to inhibit lipid oxidation and Fenton's reagent-induced protein oxidation and DNA damage. After simulated gastrointestinal digestion, FWIIE and APYMM showed increased antioxidant activity, while MWTD showed decreased activity. CONCLUSION Three novel peptides isolated from Chinese mutton ham had strong biological activity. Chinese mutton ham is potentially a functional food and an excellent source of natural antioxidants. (c) 2019 Society of Chemical Industry