Saman Shalibeik - Department of Microbiology, Faculty of biological Sciences, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
Farzaneh Mohammadzadeh Rostami - Department of Bacteriology and Virology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
Mohammad Dakhili - Department of Mycology & Parasitology, Faculty of Medicine, Qom Branch, Islamic Azad University, Qom, Iran
Mohammad Arjomandzadegan - Tuberculosis and Pediatric Infectious Research Center and Department of Microbiology, Arak University of Medical Sciences, Arak, Iran

Background and Aim : The increasing incidence of infections caused by extended-spectrum beta-lactamase (ESBL) producing Escherichia coli in Iran is of serious concern. The aim of study was to investigate the effect of aqueous hypericum perforatum extract on Escherichia coli producing ESBLs.Methods : ۴۰ strains of Escherichia coli bacteria ESBLS from clinical purified samples were taken from Arak medical university microbial research center infectious diseases and E. coli ATCC۲۵۹۲۲. Antibiogram and Biochemical tests were taken in order to verify Escherichia coli bacteria. The hypericum perforatum plant is prepared freshly from farm herb. Before drying plant in a traditional way, it should be washed with water for several times, hypericum perforatum aqueous extracts were excavated by means of reflux device with distillation and investigating the antibacterial effects of hypericum by disk diffusion method, minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC).Results : Result showed that hypericum perforatum extract to Escherichia coli ESBLs in the concentrations of ۸, ۴ and ۲ mg/ml, ۵۷.۵ percentages of bacteria out of %۱۰۰ have halo and ۴۲.۵ percentages of bacteria out of %۱۰۰ are non-halo. In these concentrations ۱, .۵, .۲۵, .۱۲۵, .۰۶۲۵, .۰۳۱۲, .۰۱۵۶ mg/ml, the percentage of sensitive bacteria (having halo) is decreased and the percentage of resistant bacteria (non-halo) increased. MIC against Escherichia coli taken in different concentrations, which concentration ۰.۰۰۷۸mg/ml was lowest among them.Conclusion : The findings demonstrate that by making a suitable herbal medicine, it is possible to hope for the treatment of resistant infections.

hypericum perforatum, E. coli, Drug resistance, ESBL