1. Antibacterial activity against porcine respiratory bacterial pathogens and in vitro biocompatibility of essential oils
- Author
-
Katy Vaillancourt, Geneviève LeBel, Philippe Bercier, and Daniel Grenier
- Subjects
Cinnamomum zeylanicum ,Pasteurella multocida ,Streptococcus suis ,Swine ,Respiratory Tract Diseases ,Microbial Sensitivity Tests ,Bacterial Physiological Phenomena ,Biochemistry ,Microbiology ,Actinobacillus suis ,Thymus Plant ,03 medical and health sciences ,chemistry.chemical_compound ,Oils, Volatile ,Genetics ,Animals ,Plant Oils ,Carvacrol ,Molecular Biology ,Actinobacillus pleuropneumoniae ,Thymol ,Nisin ,030304 developmental biology ,Swine Diseases ,0303 health sciences ,Bacteria ,biology ,030306 microbiology ,Satureja ,Bacterial Infections ,General Medicine ,Antimicrobial ,biology.organism_classification ,Anti-Bacterial Agents ,chemistry ,Biofilms ,Monoterpenes ,Winter savory ,Cymenes - Abstract
Bacterial respiratory infections affecting pigs such as pneumonia, pleuropneumonia, and pleurisy, are a major health concern in the swine industry and are associated with important economic losses. This study aimed to investigate the antibacterial activities of essential oils against major swine respiratory pathogens with a view to developing a potential alternative to antibiotics. Their synergistic interactions with the bacteriocin nisin was also examined. Lastly, we assessed the in vitro biocompatibility of the most efficient essential oils using a pig tracheal epithelial cell line. Of the nine essential oils tested, those from cinnamon, thyme, and winter savory were the most active against Streptococcus suis, Actinobacillus pleuropneumoniae, Actinobacillus suis, Bordetella bronchiseptica, Haemophilus parasuis, and Pasteurella multocida, with minimum inhibitory concentrations and minimum bactericidal concentrations ranging from 0.01 to 0.156% (v/v). The main component found in cinnamon, thyme, and winter savory oils were cinnamaldehyde, thymol, and carvacrol, respectively. Treating pre-formed S. suis and A. pleuropneumoniae biofilms with thyme or winter savory oils significantly decreased biofilm viability. We also observed a synergistic growth inhibition of S. suis with mixtures of nisin and essential oils from thyme and winter savory. Concentrations of nisin and cinnamon, thyme and winter savory essential oils that were effective against bacterial pathogens had no effect on the viability of pig tracheal epithelial cells. The present study brought evidence that essential oils are potential antimicrobial agents against bacteria associated with porcine respiratory infections.
- Published
- 2019