Evaluation of the Antibacterial Effect of Salvia Officinalis Essential Oil and its Synergistic Effect with Meropenem

Warnings by WHO concerning the antibacterial resistance was an encouragement to investigate the antibacterial effects of extracted and purchased Salvia officinalis essential oils against S. aureus, L. monocytogenes, S. pyogenes, E. coli, P. aeruginosa, and K. pneumonia by the agar well diffusion method. Besides, the checkerboard method evaluated the potential synergistic antibacterial activity of volatile sage oil and meropenem against multi-drug resistant E. coli. Results showed that the purchased oil did not have antimicrobial activity against any of the tested pathogens, while the extracted oil of S. officinalis inhibited the growth of all the tested microorganisms except the MDR K. pneumonia. The extracted oil showed the highest activity against the E. coli with an IZ of 18±0.4 mm and MIC of 6.25± 0.2 mg/ml, and the lowest activity was recorded against P. aeruginosa with an IZ of 10±0.2 mm and MIC of 25 mg/ml. In addition, SoEO showed a promising synergistic effect with meropenem against MDR E. coli. Results suggest that the EOs of S. officinalis possess antimicrobial activity, and therefore, they can be used to treat infections caused by some pathogens.