Evaluation of the Antibacterial Effect of Ethanol and Ethyl Acetate Extracts of Myrtus communis Against Antibiotic-Resistant Pseudomonas aeruginosa

Pseudomonas aeruginosa is a human and plant pathogen. The aim of this study was to investigate the antibacterial effects of ethanol and ethyl acetate extracts of Myrtus communis against antibiotic-resistant P. aeruginosa isolates. The plant was collected from the plains of Kerman province, and its ethanol and ethyl acetate extracts were prepared using a rotary machine. Pseudomonas aeruginosa strains were isolated from urine and blood samples of patients in Zabol, Iran. Antibiotic resistance pattern was determined by the agar diffusion method. Finally, the minimum inhibitory concentration (MIC) and minimum trace concentration (MTC) were determined by the microdilution method. The antibiotic-resistance patterns of the standard and clinical strains showed that P. aeruginosa was resistant to all antibiotics at the following rates: Azithromycin (25%), ampicillin (12.5%), gentamycin (0%), amoxi-clav (12.5%), cefazolin (12%), and amikacin (12.5%). The study of the effect of ethanol extract on clinical and standard P. aeruginosa strains showed that the MIC of the ethanolic extract against the standard strain of P. aeruginosa was 25 ppm. The results of this study showed good antimicrobial effects of the plant extracts against antibiotic-resistant P. aeruginosa, which can be used to treat Pseudomonas infections.