Unwashed surimi(UWS)is susceptible to severe lipid oxidation during frozen storage,yet the underlying mechanism remained poorly understood and methods to solve this problem were limited.This study aimed to elucidate t...Unwashed surimi(UWS)is susceptible to severe lipid oxidation during frozen storage,yet the underlying mechanism remained poorly understood and methods to solve this problem were limited.This study aimed to elucidate the core oxidative pathways in frozen UWS and screen for potent,food-derived polyphenolic antiox-idants.We systematically investigated the effects of 17 food polyphenol extracts(FPEs),revealing a novel mechanistic insight:hemoglobin(Hb)autoxidation is the primary source of the hydroxyl radical(⋅OH),which directly triggers lipid oxidation.Correlation analysis further confirmed that lipid oxidation was significantly and positively correlated with Hb autoxidation and the activities of key radical-producing enzymes,specifically xanthine oxidase(XOD)and nitric oxide synthase(NOS).Among the tested FPEs,apple polyphenol extract demonstrated unparalleled efficacy,inhibiting thiobarbituric acid reactive substances(TBARs)formation by 67%after three freeze-thaw cycles(P<0.05).Mechanistically,its superiority stems from a dual-action capability:it not only exhibited strong free radical-scavenging activity(2,2-Diphenyl-1-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS⋅^(+))scavenging>75%)but also potently inhibited key pro-oxidative enzymes,with remarkable inhibition rates against lipoxygenase(LOX,92.15%)and,crucially,XOD(98.04%).These findings provide a crucial theoretical basis for selecting highly effective natural antioxidants to delay lipid oxidation and enhance the frozen storage quality of UWS.展开更多
基金supported by National Natural Science Foundation of China(32372412).
文摘Unwashed surimi(UWS)is susceptible to severe lipid oxidation during frozen storage,yet the underlying mechanism remained poorly understood and methods to solve this problem were limited.This study aimed to elucidate the core oxidative pathways in frozen UWS and screen for potent,food-derived polyphenolic antiox-idants.We systematically investigated the effects of 17 food polyphenol extracts(FPEs),revealing a novel mechanistic insight:hemoglobin(Hb)autoxidation is the primary source of the hydroxyl radical(⋅OH),which directly triggers lipid oxidation.Correlation analysis further confirmed that lipid oxidation was significantly and positively correlated with Hb autoxidation and the activities of key radical-producing enzymes,specifically xanthine oxidase(XOD)and nitric oxide synthase(NOS).Among the tested FPEs,apple polyphenol extract demonstrated unparalleled efficacy,inhibiting thiobarbituric acid reactive substances(TBARs)formation by 67%after three freeze-thaw cycles(P<0.05).Mechanistically,its superiority stems from a dual-action capability:it not only exhibited strong free radical-scavenging activity(2,2-Diphenyl-1-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS⋅^(+))scavenging>75%)but also potently inhibited key pro-oxidative enzymes,with remarkable inhibition rates against lipoxygenase(LOX,92.15%)and,crucially,XOD(98.04%).These findings provide a crucial theoretical basis for selecting highly effective natural antioxidants to delay lipid oxidation and enhance the frozen storage quality of UWS.
