Iron-binding peptides are an alternative for increasing the bioavailability of iron and to decreasing its pro-oxidant effect. This study aimed to synthesize and characterize peptide-iron complexes using FeCl or FeSO as the iron precursor compounds. Whey protein isolate (WPI), WPI hydrolyzed with pancreatin, and its fractions obtained via ultrafiltration (cut-off 5kDa) were used as ligands. The fluorescence intensity of the ligands significantly decreased as the iron concentration increased as a result of metal coordination with the iron-binding sites, which may have led to changes in the microenvironment of tryptophan. For both iron precursor compounds, the primary iron-binding site was carboxylate groups, and the linkage occurred via a bidentate coordination mode with two vibrational modes assigned to the COOFe linkage. However, infrared spectroscopy and thermal analysis results showed that the dynamics of the interaction is different for the iron precursor. The iron source may be of great importance because it may impact iron absorption and the pro-oxidant effect of the mineral.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.