Antimicrobial Susceptibility ofEscherichia coliStrains Isolated fromAlouattaspp. Feces to Essential Oils
This study evaluated thein vitroantibacterial activity of essential oils fromLippia graveolens(Mexican oregano),Origanum vulgaris(oregano),Thymus vulgaris(thyme),Rosmarinus officinalis(rosemary),Cymbopogon nardus(citronella),Cymbopogon citratus(lemongrass), andEucalyptus citriodora(eucalyptus) againstEscherichia coli(n=22) strains isolated fromAlouattaspp. feces. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for each isolate using the broth microdilution technique. Essential oils of Mexican oregano (MIC mean = 1818 μg mL−1; MBC mean = 2618 μg mL−1), thyme (MIC mean = 2618 μg mL−1; MBC mean = 2909 μg mL−1), and oregano (MIC mean = 3418 μg mL−1; MBC mean = 4800 μg mL−1) showed the best antibacterial activity, while essential oils of eucalyptus, rosemary, citronella, and lemongrass displayed no antibacterial activity at concentrations greater than or equal to 6400 μg mL−1. Our results confirm the antimicrobial potential of some essential oils, which deserve further research.