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.</jats:p
