Potencial antimicrobiano e antiaderente do óleo essencial de Origanum vulgare contra Enterobacter cloacae.

Abstract

Enterobacter cloacae, a bacterium found in the gastrointestinal tract and oral cavity of healthy individuals, can represent an important opportunistic microorganism that causes hospital-acquired infections, such as aspiration pneumonia in patients admitted to Intensive Care Units. This bacterium is able to form biofilms, secrete cytotoxins and is resistant to various antimicrobials. In this sense, it is worth highlighting the growing search for natural products with antimicrobial, antifungal and anti-adherent properties, such as essential oils, as they are products of plant origin, low cost and easily accessible to the population. Among the many essential oils with pharmacological properties, Origanum vulgare stands out. The aim of this study was to analyze the antibacterial and anti-adherent activity of Origanum vulgare essential oil against Enterobacter cloacae. Methodological tests were carried out using broth microdilution techniques in 96-well plates to determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC), and the inclined tube technique to determine the Minimum Inhibitory Concentration of Adherence (MICA), in the presence of 5% sucrose. The essential oil of Origanum vulgare was found to have an MIC of 128 µg/mL and CBM of 256 µg/mL against the Enterobacter cloacae strain. The MICA of the essential oil and the positive control (0.12% chlorhexidine digluconate) were not found at the concentrations tested. Therefore, it was possible to conclude that the essential oil of Origanum vulgare had a high antimicrobial potential and was considered bactericidal against Enterobacter cloacae, although there was no anti-adherent activity at the concentrations tested and in the methodology applied.