The Screening Strategy and Activity Investigation of Skipjack Tuna (Katsuwonus pelamis) Umami Peptides Based on Computer Simulation Prediction and Experimental Hydrolysis

Marine-derived proteins are important sources in the preparation of umami peptides due to their delicious and unique taste. The research endeavored to elucidate the established umami peptide library derived from Skipjack tuna protein through a combined approach of computational and experimental proteolysis. A total of five potential shared umami peptides (GVGGHGAGG, GVTGVG, GGVAGCQGK, MANR, and SPAAK) were identified through database and molecular docking, which revealed that hydrogen bonds and electrostatic forces critically influence the interaction between peptides and T1R1/T1R3. The specific amino acids within the T1R1/T1R3 corresponding to glutamic acid, serine, arginine, aspartic acid, and histidine significantly influenced the affinity for umami peptides. It was verified through sensory and electronic tongue analysis that all these peptides exhibit umami performance and flavor-enhancing effects. Furthermore, bioinformatic predictions and computer simulations exploring the biological activity of umami peptides revealed that GVGGHGAGG, GVTGVG, and GGVAGCQGK, combined with Keap1, presented potential antioxidant activity. These observations offered new insights for identifying bioactive umami peptides from aquatic products and a theoretical foundation for developing novel seasonings.