Characterization and structure-activity relationship of novel umami peptides isolated from Thai fish sauce.

Fish sauce has a prominent umami flavor. In this study, umami peptides were isolated, purified and identified from Thai fish sauce, and their structure-activity relationships were analyzed. Six novel umami peptides were characterized and verified by using sensory evaluation and a electronic tongue. Molecular docking with T1R1/T1R3 receptors showed that the interaction forces were mainly hydrogen bonds, electrostatic interaction and van der Waals force. In the constructed three dimensional quantitative structure-activity relationship model (3D-QSAR) model, the regression coefficient (R2) for the degree of dispersion between the predicted molecular and the experimental values of the six peptides was 0.976. The association between the structure and activity of umami peptides was revealed through 3D-QSAR. Results showed that the spatial effect was significant for long chain peptides.