Antimicrobial effect against different bacterial strains and bacterial adaptation to essential oils used as feed additives

作者：Brandao Melo Antonio Diego; Amaral Amanda Figueiredo; Schaefer Gustavo; Luciano Fernando Bittencourt; de Andrade Carla; Costa Leandro Batista; Rostagno Marcos Horacio

来源：Canadian Journal of Veterinary Research, 2015, 79(4): 285-289.

The aim of this study was to evaluate the antimicrobial activity and determine the minimum bactericidal concentration (MBC) of the essential oils derived from Origanum vulgare (oregano), Melaleuca alternifolia (tea tree), Cinnamomum cassia (cassia), and Thymus vulgaris (white thyme) against Salmonella Typhimurium, Salmonella Enteritidis, Escherichia coli, Staphylococcus aureus and Enterococcus faecalis. The study also investigated the ability of these different bacterial strains to develop adaptation after repetitive exposure to sub-lethal concentrations of these essential oils. The MBC of the essential oils studied was determined by disc diffusion and broth dilution methods. All essential oils showed antimicrobial effect against all bacterial strains. In general, the development of adaptation varied according to the bacterial strain and the essential oil (tea tree. white thyme. oregano). Therefore, it is important to use essential oils at efficient bactericidal doses in animal feed, food, and sanitizers, since bacteria can rapidly develop adaptation when exposed to sub-lethal concentrations of these oils.

• 出版日期2015-10