Mechanisms of epigallocatechin-3-gallate-loaded metal−organic framework in preventing oxidative degradation of shrimp (Litopenaeus vannamei) surimi gel

Abstract

This work aimed to elucidate the deterioration mechanisms of shrimp surimi gels during refrigerated storage, and the regulatory mechanisms of epigallocatechin-3-gallate loaded cyclodextrin-based metal−organic framework (EGCG@CD-MOF) as a model antioxidant. Labele-free proteomics provided a quantitative analysis of the differential proteomic signatures of degraded proteins. Structural proteins, like myosin, paramyosin, titin, laminin, and α-actinin, along with calcium regulatory proteins, like calcineurin and sarcoplasmic calcium-binding protein were found to be highly susceptible to oxidative degradation during refrigeration. In contrast, EGCG@CD-MOF significantly mitigated protein degradation. Electron spin resonance (ESR) data demonstrated that EGCG@CD-MOF efficiently inhibited free radical accumulation over the 8-week refrigeration period. Scanning electron microscopy (SEM) further confirmed its ability to prevent network structural deterioration. Additionally, rheological, infrared, and molecular dynamics analyses supported the sustained interaction between EGCG@CD-MOF and proteins, with key interaction sites identified at residues ASP-131, ARG-92, SER-97, ASP-98, Lys-12, Gly-168, Glu-170, Arg-8, and Gly-6.