Antibacterial Effects of Extract of Sage and Betony Plants on Staphylococcus aureus: In Vitro and Animal Model

Background and Aim : Infectious diseases are one of the most common diseases around the world which impose enormous financial burden on society. Staphylococcus aureus is an important causes of nosocomial infections and multi drug resistance. Although synthetic antibiotics have been able to play an important role in treatment of infectious diseases in past decades, however problems related to microbial resistance of antibiotics have caused that the medical plants to be considered as an alternative.Methods : In this study, aqueous and ethanolic extracts were prepared from dried leaves of the Salvia officinalis and Stachys lavandulifolia, then anti-bacterial activities of the extracts for Staphylococcus aureus were experimented, first by the method of well diffusion in agar, and later the amount of the MIC and MBC of the extracts were measured by broth dilution method. In animal model study, first ۵×۱۰۵ CFU/ml of bacteria was intraperitoneally injected and after ۲۴ hours, ۰.۵ml (as MBC concentration of each the extracts) of extracts, to female BALB/c mice was intrapertioneally injected. Then, the counting of bacterial clonies in spleen were determined with cultivation on Mueller Hinton agar after ۷ days as the standard protocol.Results : The experiment results concerning the determination of growth inhibition diameter in agar showed that the maximum of growth inhibition diameter is related to the ethanolic extract of Salvia officinalis (۲۰ mm), and the minimum of growth inhibition diameter is related to ethanolic extract of Stachys lavandulifolia (۱۰ mm) at the highest concentration (۴۰۰ mg/ml). In conditions of in vivo, after ۴۸ hours spleen supernatant cultivation, the average number of bacteria for ethanolic extracts of the Salvia officinalis and Stachys lavandulifolia were ۱.۸×۱۰۳ CFU/ml and ۶.۶×۱۰۳ CFU/ml respectively and for aqueous extract of Salvia officinalis was ۱۴.۶×۱۰۳ CFU/ml. These results showed significantly decrease in number of bacteria in all experimental groups (p˂۰.۵) compared to control group.Conclusion : In general, the results of evaluations in experimental conditions and the animal model showed that ethanolic and aqueous extracts of Salvia officinalis and ethanolic extract of Stachys lavandulifolia have the effective antibacterial activity against mentioned bacteria and can be useful to treatment of nosocomial infections.

کلیدواژه ها:

Antimicrobial ، Salvia officinalis ، Stachys lavandulifolia ، Staphylococcus aureus