Study of the Combined Effect of Zataria multiflora Essential Oil with Tetracycline and Vancomycin against Biofilms of Enterococcus faecalis Clinical Isolates

Background and Aim : Introduction: Enterococci are optional gram-positive anaerobic bacteria that are naturally present in the human gastrointestinal flora, known as important pathogens around the world, especially in nosocomial infections. Given the role of biofilms in antibiotic resistance as well as the pathogenicity of new treatment methods to eliminate the appropriate conditions for the formation of biofilms by bacteria, which acts as a protective coating against the host immune system and antibiotics, it is necessary to it seems. One of the proposed methods to combat bacterial biofilm is the use of alternative antibacterial treatments, which include the combined use of herbal essential oils and antibiotics. The aim of this study was to investigate the combined effect of Zataria multiflora essential oil and tetracycline and vancomycin antibiotics against the biofilm of clinical strains of bacterial Enterococcus fecalis. Methods : This study was performed on ۳۰ samples of Enterococcus faecalis isolated from patients with office infections referred to Milad Hospital in ۲۰۰۹. Zataria multiflora essential oil was extracted and its chemical compounds were analyzed by gas chromatography device with mass spectrometry (GC-MS). Antibacterial activity of thyme essential oil and tetracycline and vancomycin antibiotics were investigated by microdermabrasion method against ۳۰ strains of Enterococcus faecalis and the minimum inhibitory concentration (MIC) alone and in combination was determined against the formation of biofilm on polystyrene microtiter plate. The results of antimicrobial interaction were obtained by checkerboard titration method by determining the fraction inhibitory concentration index (FICI). Results : Based on the results of this study, ۱۰ strains of Enterococcus faecalis were able to produce stable biofilm. The results also showed that Zataria multiflora essential oil alone and in combination with tetracycline and vancomycin antibiotics has anti-biofilm activity. Conclusion : Herbal essential oils can be used effectively to control the biofilms of Enterococcus faecalis. This issue highlights the importance of natural compounds as anti-biofilm and potential antimicrobial agents.

کلیدواژه ها:

Biofilm ، Enterococcus faecalis ، Zataria multiflora Essential Oil ، Tetracycline ، Vancomycin ، Synergistic