antibacterial effects of origanum vulgare essence against multidrug-resistant acinetobacter baumannii isolated from selected hospitals of tehran, iran

Infection due to acinetobacter baumannii has become a significant challenge to modern healthcare systems. the rapid emergence and global dissemination of a. baumannii as a major nosocomial pathogen is remarkable and it demonstrates its successful adaptation to the 21st century hospital environment. recent studies have discussed about essential oil of origanum vulgare against a range of bacteria, including various species of staphylococcus, pseudomonas, bacillus and escherichia coli. the present study aimed to investigate the inhibitory effects o. vulgare essence against multidrug-resistant (mdr) strains of a. baumannii from selected hospitals in tehran, iran. this oil was obtained using the hydrodistillation method and analyzed by gas chromatography mass spectrography (gc/ms). the antimicrobial activity against mdr isolates was achieved using disc diffusion method and macro-broth dilution assay. analysis of the essential oil revealed the presence of pulegone (68.59%) piperitone (7.8%), piperitenone (7.8%), 1, 8-cineole (1.3%), and carvacrol (1.6%) as the major components. the results showed a significant activity against mdr a. baumannii with inhibition zones and minimal inhibitory concentration values in the ranges of 7-15 mm and 20-35 µl/ml respectively. this investigation showed that the essence oil of o. vulgare had a potent antimicrobial activity against mdr a. baumannii. further research is required to evaluate the practical values of therapeutic applications.