Antibacterial activity of peptides extracted from tryptic hydrolyzate of whey protein by nanofiltration.
Gilles Robitaille , Demers-Mathieu, V., S. F. Gauthier, M. Britten, I. Fliss and J. Jean
Nom de la revue: International dairy journal 28(2): 94-101.
Ultrafiltration permeate of whey protein tryptic hydrolyzate was processed by nanofiltration (NF) to obtain retentate (NFR) and permeate (NFP) that were then tested as inhibitors of Listeria, Staphylococcus aureus and Escherichia coli. NFR at 20pmgpmLp# was most effective as an inhibitor (Pp<p0.001); whereas E.pcoli was relatively resistant, the effect on Listeria and S.paureus was greater at 20pmgpmLp# than at 10pmgpmLp# (Pp<p0.01). Peptide analysis revealed that NFR was rich in anionic peptides over eight amino acid residues in length. The antibacterial activity of two anionic peptides (8491 and 125135) and a cationic peptide (3642) derived from o-lactoglobulin was tested. Peptide 125135 was more inhibitory (Pp<p0.05) than peptide 8491 against Listeria monocytogenes and S.paureus; peptide 3642 was not inhibitory. NFR appears to have potential as a natural bio-preservative.