Background: β-lactamase enzymes are one of the most important factors in generating antibiotic resistance among gram-negative bacteria. Klebsiella pneumoniae is an opportunistic pathogen from the Enterobacteriaceae family, which plays a major role in the development of hospital infections and people with underlying diseases. This study was aimed to investigate the antimicrobial effect of vitreous essential oil on strains containing antibiotic resistant genes in clinical isolates of Klebsiella pneumoniae in Zahedan.Methods and Materials: In order to identify chemical compounds and to investigate the antibacterial effects of Teucrium Polium extract, the leaves of this plant were collected from their natural habitat in May 2018 at full flowering stage. Extraction was carried out by water distillation method. Antibacterial activity of the extract of this plant, the least inhibitory concentration of growth on the resistant strains of Klebsiella pneumoniae was performed.Results: The essential oil yield of the Teucrium Polium was 75%. Of the 29 compounds identified in the essential oil of the Teucrium Polium, the combination of alphapinene with 12.52%, linalool was the highest in the essential oil of 10.63%. Of the 120 isolates of Klebsiella pneumoniae, 52 isolates in the initial screening were positive for ESBL production, of which 39 isolates (32.5%) were positive in the phenotypic confirmatory assay. 11 isolates (10.8%) had AmpC gene. Based on the results of PCR, 76.9%, 12.8%, 30.8%, 28.2%, 25.7%, 56.4% of the isolates were carriers of MOX, CIT, DHA, ACC, EBC genes and FOX, respectively.Conclusion: The results of antimicrobial resistance study of isolates showed that the highest resistance to Erythromycin Antibiotics (92.5%), Cefotaxime (38.4%) and Ceftriaxone (35.9%), respectively, while the highest susceptibility was observed in Colistin antibiotics (98.3%), Imipenem (90%) and Amikacin (88.3%), respectively. The essential oil of the Teucrium Polium had a significant antibacterial effect. Due to the high percentage of high concentrations of alphapinene and linalool in the essential oil of the Teucrium Polium with antibacterial properties and can be used to cope with certain pathogenic bacteria.
