Rapid screening and taste mechanism investigation of novel umami peptides from krill using combined virtual and actual enzymatic hydrolysis
Minli Tian, Gailing Tang, Yue Zhang, Xinyu Gao, Huali Wang, Suwen Liu, Qingdai Liu, Jianhui Liu, Hao WangAbstract
To enhance the utilization value of krill, this study investigated umami peptides in krill using cutting-edge techniques, including virtual proteolysis combined with actual enzymatic hydrolysis, machine learning models, molecular docking, and molecular dynamics simulations. Virtual proteolysis results indicated that peptides derived from dual proteolysis with alkaline protease and papain exhibited a high degree of hydrolysis and umami intensity, which was selected as the actual hydrolysis method. LC-MS/MS analysis of the hydrolysate identified 948 peptide fragments. Three non-toxic, water-soluble potential umami peptides DEDFPW (DW6), DWDDMEKIW (DW9), and NWDDMEKVW (NW9) were identified through virtual screening and machine learning. Molecular docking indicated umami peptide-receptor complexes primarily bind through hydrogen bonds and hydrophobic interactions, with 18 amino acid residues playing a pivotal role. Molecular dynamics simulations (MDS) indicated DW9 exhibited the highest stability. Sensory evaluation results demonstrated that DW9 exhibited the most pronounced umami intensity and flavour-enhancing capacity.