Antimicrobial effects of marine algal extracts and cyanobacterial pure compounds against five foodborne pathogens

Dominic Dussault, Khanh Dang Vu, Tifanie Vansach, F. David Horgen, Monique Lacroix

INRS-Institut Armand-Frappier, Canadian Irradiation Center, Research Laboratories in Sciences Applied to Food, 531, Blvd des Prairies, Laval, QC H7V 1B7, Canada.

Abstract

The marine environment is a proven source of structurally complex and biologically active compounds. In this study, the antimicrobial effects of a small collection of marine-derived extracts and isolates, were evaluated against 5 foodborne pathogens using a broth dilution assay. Results demonstrated that algal extracts from Padina and Ulva species and cyanobacterial compounds antillatoxin B, laxaphycins A, B and B3, isomalyngamide A, and malyngamides C, I and J showed antimicrobial activity against Gram positive foodborne pathogens (Listeria monocytogenes, Bacillus cereus and Staphylococcus aureus) at low concentrations (500 μg/ml). None of the algal extracts or cyanobacterial isolates had antibacterial activity against Gram negative bacteria (Escherichia coli and Salmonella enterica serovar Typhimurium).

Keywords: Antimicrobial; Foodborne pathogens; Marine algae; Cyanobacteria.