Novel umami peptides from Takifugu rubripes and evaluation of their umami perception through virtual screening and biolayer interferometry

Umami peptides from Takifugu rubripes muscle contribute significantly to its umami taste. This study employed both enzymatic hydrolysis and ultrasound pretreated enzymatic hydrolysis to generate potential umami peptides from T. rubripes . The umami properties of the identified peptides were evaluated, screened, synthesized, and validated. Through Nano-LC/MS analysis, ultrasound pretreated enzymatic hydrolysis yielded a greater number of peptides of varying size (162 peptides) and showed better umami flavor compared to single enzymatic method. Among the identified sequences, 24 peptides were predicted as umami using Q value, iUmami-SCM, and Umami_YYDS taste models. The umami properties of five synthetic peptides (VDFDDLHR, KEPNRQWTPR, PFGNTHNNFK, YDSTHGRFKGEVK, and TGESGAGKTVNTKR) were further confirmed through sensory evaluation, molecular simulation, and biolayer interferometry (BLI). Sensory evaluation revealed that the intensity thresholds for these peptides ranged from 0.37 to 0.49 mmol/L. Molecular simulations and BLI analyses provided further evidence of high umami intensity for these peptides, as evidenced by their effective interaction with the specific umami T1R1 receptor. Overall, this study provides an effective reference for the study of umami peptides in T. rubripes .