Screening of algal extracts antimicrobial activity for cheese preservation and characterization of active extracts
Ariane Tremblaya, Martha Paola Rivera Rodrígueza, Nellie Francezona,b, Samuel Cashman-Kadria, Samuel Côtéa, Lucie Beaulieua,c,*
aInstitut sur la nutrition et les aliments fonctionnels, Département des sciences des aliments, Université Laval, 2425 rue de l’Agriculture, Pavillon Paul-Comtois, Québec, QC, Canada, G1V 0A6
bInstitut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), 42 Rue Georges Morel, 49070 Beaucouzé, France
cQuébec-Océan, 1045 avenue de la Médecine, Pavillon Alexandre-Vachon, Université Laval, Québec, QC, Canada, G1V 0A61
Cheese is a food at risk of spoilage by undesirable bacteria and mold. These microorganisms can compromise the cheese’s organoleptic properties, safety, and shelf life. There is also an increased consumer awareness about the composition of their food. Indeed, there is a need to develop natural antimicrobials as alternatives to conventional food additives. It was previously demonstrated that diverse algal compounds (peptides, lectins, polysaccharides, phenolic compounds, terpenes, fatty acids) exhibit antimicrobial activities. However, there are only a few studies about the antibacterial activity of seaweed extracts from Eastern Canada, and their antifungal activity is undocumented. The study aimed to produce seaweed extracts and test them for their antifungal and antibacterial activity.Food-grade aqueous and ethanolic extracts from various seaweed species (Alaria esculenta, Chondrus crispus, Fucus vesiculosus, Palmaria palmata, Porphyra umbilicalis and Saccharina latissima) were produced, as well as aqueous, hexane and ethyl acetate sub-fractions from ethanolic extracts. Their antifungal and antibacterial activities were assessed against alteration strains from the dairy industry. No antifungal activity was found. However, some ethanolic extracts and their sub-fractions exhibited antibacterial activities against thermoresistant strains (Clostridium tyrobutyricum MK183, Lactobacillus plantarum RKG 2-212) from the cheese industry. The minimal inhibitory concentrations ranged from 0.063 to 0.50 mg/mL. Potential antibacterial molecules such as 2,2'-(2-Hydroxy-1,3-phenylene)bis(oxoacetic acid), rosmarinic acid, 3-methoxysalicylic acid and astilbin were identified. The results obtained open new prospects for the use of seaweed extracts as a natural agent for cheese defects prevention and cheese preservation.
