Chao Du,Zhenzhen Hui,Na Li,Kaiyue Liu,Yong Wang,Ping Wang,Shuyang Sun
This investigation sought to identify antioxidative peptides derived from Meretrix meretrix L. (MML) throughout simulated gastrointestinal digestion (SGD) via in vitro and in silico strategies. The study demonstrated that hydrolysates from MML captured at various SGD phases showcased robust antioxidative activity. These hydrolysates also displayed a protective role against hydrogen peroxide-induced stress in Raw 264.7 cells. Notably, hydrolysates sourced from the intestinal phase of digestion (MMLHs-I) markedly inhibited the reduction of cell viability, limited the generation of reactive oxygen species under oxidative stress conditions, and promoted the activity of key antioxidant enzymes including superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase, thus amplifying the cells' antioxidative defense system. Through nLC-MS/MS analysis, 105 peptides tracing back to 18 parent proteins were pinpointed in MMLHs-I, with 18 of these peptides previously reported in the BIOPEP-UWM database. Subsequent in silico analysis, alongside empirical antioxidant activity assays, pinpointed the peptide WLV as an exceptional antioxidative agent, demonstrating an IC 50 of 0.125 mg/mL in the ABTS assay and an impressive 15.18 μmol Trolox/mg in the ORAC assay. The outcomes highlight MML's promise as a novel source of antioxidative peptides, positioning peptide WLV as a potentially valuable addition to functional foods designed to combat oxidative stress.
Purpose This study investigated the basic composition, in vitro digestibility, biological activities, and potential bioactive peptides of Pacific oyster (PO), Mytilus edulis (ME), Argopecten irradians (AIS), and Meretrix meretri x L. (MML) after simulated gastrointestinal digestion (SGD). Methods SGD products were prepared using the INFOGEST 2.0 model, and their nutritional properties and biological activities were analyzed. A comprehensive peptidomic profiling of the digested samples was conducted using nano-liquid chromatography-tandem mass spectrometry (nano-LC MS/MS) analysis. Results All four shellfish exhibited a nutritional profile characterized by high protein and low-fat content. The digestibility of shellfish increased progressively, while the average molecular weight (MW) of the hydrolysates gradually decreased during SGD, with the intestinal hydrolysates showing the highest overall digestibility. Biological activity analysis demonstrated that intestinal digestion products from all four species exhibited notable ABTS radical scavenging activity and α-glucosidase inhibition activity, with PO and ME exhibiting the strongest effects. A total of 349, 99, 314 and 105peptides were identified from the digestion products of PO, ME, AIS, and MML, respectively. Among these, PO and AIS showed the highest sequence similarity, sharing 69 identical peptides. By contrast, MML displayed distinct peptidomic characteristics, including a higher proportion of large MW peptides. Conclusion This study provides a comprehensive peptide catalog of shellfish digestion products and offers new insights into the biological activities of shellfish-derived peptides, supporting their potential as functional food resources.