Study of the bactericidal and bacteriostatic effects of olive oil, sesame oil and their synergism on Pseudomonas aeruginosa in vitro

Abstract

<strong>Background and aims:</strong> Nosocomial infections are common problems in developing and developed countries. One of the pathogens that causes these infections is <em>Pseudomonas aeruginosa</em>. According to the antibiotical resistance of this bacteria, It is essential to find new treatments like new herbal medicine. This study was aimed to determine <em>in vitro</em> antibacterial effects of sesame oil, olive oil and their synergism on <em>P. aeruginosa</em>.<br /><strong>Methods:</strong> In this experimental study, first, olive oil and sesame oil were obtained by cold-pressing assay. Then, <em>P.aeruginosa</em> ATCC 27853 was prepared from Iranian Research Organization for Science and Technology. Oils and their mixture with the same proportion were made in concentrations from 2 to 1024 mg/ml and the antibacterial character of these oils on <em>P.aeruginosa</em> was investigated by broth micro dilution method and then the amounts of the MIC and the MBC were demonstrated.<br /><strong>Results:</strong> The MIC of olive oil, sesame oil and their synergism on <em>P.aeruginosa</em> were reported; 16 mg/ml, 128 mg/ml and 128 mg/ml and the MBC of these oils were indicated; 64 mg/ml, 512 mg/ml and 512 mg/ml, respectively.<br /><strong>Conclusion:</strong> This study showed that sesame oil, olive oil and their synergism can inhibit bacterial growth. Olive oil has more antibacterial effect on this bacteria than sesame oil and their synergism. So, we conclude that there was no synergistic effect in these oils.