Isolation, identification, and virtual screening of peptides with ferrous ion chelating activity from poultry blood hemoglobin

To improve the utilization and value of poultry blood, identification, virtual screening, and binding mode of Fe 2+ chelating peptide from poultry blood hemoglobin were investigated in this study. Virtual enzymatic hydrolysis results indicated that the peptide obtained from the hydrolysis of duck blood hemoglobin by thermolysin exhibited the highest Fe 2+ chelating activity. The crude peptides were separated, and the fraction with the best Fe 2+ chelating ability was identified. Subsequently, virtual screening and molecular docking were performed on the identified peptides. Finally, 6 peptides with potential biological activity as well as good intestinal absorption, without toxicity, allergenicity, and bitterness were screened through virtual screening. Among them, 4 peptides can stably bind to Fe 2+ . They showed two binding modes: peptides that presented a loop structure upon binding to Fe 2+ have a binding site at the C-terminus; peptides that showed a β-folded structure upon binding to Fe 2+ , with the binding site in the middle of the peptide chain. The carboxyl O atom was the main binding site. The poultry blood hemoglobin peptides with Fe 2+ chelating ability were isolated and identified, and the chelating modes were analyzed to offer a theoretical foundation and technical strategy for the development of new iron nutrition fortifiers. • Proteases were efficiently selected by virtual enzymatic hydrolysis. • Combined virtual enzymatic hydrolysis and experiments to quickly obtain Fe 2+ chelating peptides. • 6 novel potential bioactive peptides with application value were rapidly selected. • The binding modes of 4 peptides with Fe 2+ were explored through molecular docking.