Identification of umami peptides based on virtual screening and molecular docking from Atlantic cod (Gadus morhua)

Umami peptides have currently become the research focus in the food umami science field and the key direction for umami agent development. This is because umami peptides have good processing characteristics, umami and nutritional values. We here used virtual screening (including online enzymolysis through ExPASy PeptideCutter, bioactivity screening using the PeptideRanker, toxicity and physicochemical property prediction using Innovagen and ToxinPred software), molecular docking, and electronic tongue analysis to identify umami peptides generated from Atlantic cod myosin. Twenty-three putative umami peptides were screened from the myosin. Molecular docking results suggested that these 23 peptides could enter the binding pocket in the T1R3 cavity, wherein Glu128 and Asp196 were the main amino acid residues, and that hydrogen bonding and electrostatic interactions were the main binding forces. Twelve synthetic peptides tested on the electronic tongue exhibited umami taste and a synergistic effect with monosodium glutamate (MSG). Among them, GGR, AGCD, and SGDAW had higher umami intensities than the other peptides, while SGDAW and NDDGW exhibited stronger umami-enhancing capabilities in 0.1% MSG solution. This study offers a method for the rapid screening of umami peptides from marine protein resources and places the foundation for their application in the food industry.