Abstract
Background: The outbreaks of multidrug-resistant Acinetobacter baumannii related to nosocomial infections the organism which the leading cause of mortality in hospitalized patients. Therefore, exploration for alternative antibacterial agents, essential oils have become of major interest.
Objectives: This study aimed to determine the effect of Satureja khuzestanica Jamzad essential oil on multidrug-resistant nosocomial isolates of A. baumannii.
Methods: Twenty one non-repetitive multidtug-resistant isolates of A. baumannii were collected in 2014 from Imam Hossein and Shahid Motahari Burn hospitals in Tehran. Antibacterial susceptibility to 12 antibiotics was measured by disc diffusion. Essential oil extraction of S. khuzestanica aerial parts was carried out with Hydro-distillation, and susceptibility to the oil was initially determined using discs containing 1.64 mg essential oil in 10% dimethyl sulfoxide. Minimum inhibitory and bactericidal concentrations of the essential oil were determined by broth microdilution.
Results: The disc diffusion results showed that all isolates were resistant to nine of the 12 antibiotics test which is determined as multidrug-resistant. The disc diffusion results for S. khuzistanica essential oil were revealed inhibition zones of 29 - 42 mm. MIC values were 0.31 mg/mL for all test isolates and MBCs were from 0.31 to 0.62 mg/mL which shows the bactericidal activity of the essential oil.
Conclusions: The carvacrol-rich essential oil of S. khuzistanica showed strong antibacterial activity against all multidtug-resistant as clinical isolates of A. baumannii.