title: Evidence of Antibacterial Activities in Peptide Fractions Originating from Snow Crab (Chionoecetes opilio) By-Products.
abstract: Antibacterial peptide fractions generated via proteolytic processing of snow crab by-products exhibited activity against Gram-negative and Gram-positive bacteria. Among the bacterial strains tested, peptide fractions demonstrated inhibitory activity against the Gram-negative bacteria such as Aeromonas caviae, Aeromonas hydrophila, Campylobacter jejuni, Listonella anguillarum, Morganella morganii, Shewanella putrefasciens, Vibrio parahaemolyticus and Vibrio vulnificus and against a few Gram-positive bacteria such as Listeria monocytogenes, Staphylococcus epidermidis and Streptococcus agalactiae. The principal bioactive peptide fraction was comprised mainly of proteins and minerals (74.3 and 15.5%, respectively). Lipids were not detected. The amino acid content revealed that arginine (4.6%), glutamic acid (5.3%) and tyrosine (4.8%) residues were represented in the highest composition in the antibacterial peptide fraction. The optimal inhibitory activity was observed at alkaline pH. The V. vulnificus strain, most sensitive to the peptide fraction, was used to develop purification methods. The most promising chromatography resins selected for purification, in order to isolate peptides of interest and to carry out their detailed biochemical characterization, were the SP-Sepharose™ Fast Flow cation exchanger and the Phenyl Sepharose™ High Performance hydrophobic interaction media. The partially purified antibacterial peptide fraction was analyzed for minimum inhibitory concentration (MIC) determination, and the value obtained was 25 μg ml(-1). Following mass spectrometry analysis, the active peptide fraction seems to be a complex of molecules comprised of several amino acids and other organic compounds. In addition, copper was the main metal found in the active peptide fraction. Results indicate the production of antibacterial molecules from crustacean by-products that support further applications for high-value bioproducts in several areas such as food and health.
authors.affiliation: Université du Québec à Rimouski (UQAR), 300 allée des Ursulines, Rimouski, QC, G5L 3A1, Canada. lucie_beaulieu@uqar.qc.ca.|Institute of Nutraceuticals and Functional Food (INAF), Université Laval, Québec, QC, G1V 0A6, Canada. lucie_beaulieu@uqar.qc.ca.
authors.forename: Lucie
authors.initials: L
authors.lastname: Beaulieu
authors.affiliation: Université du Québec à Rimouski (UQAR), 300 allée des Ursulines, Rimouski, QC, G5L 3A1, Canada.
authors.forename: Jacinthe
authors.initials: J
authors.lastname: Thibodeau
authors.affiliation: Aquatic Products Technology Centre (CTPA, MAPAQ), 96, montée de Sandy Beach, office 1.07, Gaspé, QC, G4X 2V6, Canada.
authors.forename: Michel
authors.initials: M
authors.lastname: Desbiens
authors.affiliation: Institut des sciences de la mer (ISMER, UQAR), 310 allée des Ursulines, Rimouski, QC, G5L 3A1, Canada.
authors.forename: Richard
authors.initials: R
authors.lastname: Saint-Louis
authors.affiliation: Université de Caen, Esplanade de la Paix, 14032, Caen cedex, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Zatylny-Gaudin
authors.affiliation: Aquatic Products Technology Centre (CTPA, MAPAQ), 96, montée de Sandy Beach, office 1.07, Gaspé, QC, G4X 2V6, Canada.
authors.forename: Sharon
authors.initials: S
authors.lastname: Thibault
keywords: Antibacterial activities; Peptide fractions; Snow crab by-products