Antimicrobial effect of Rosmarinus officinalis extracts biofilm in some important human bacterial pathogens

Microorganisms form biofilm from a self-produced extracellular polymeric, substances under which they develop their colony. These biofilms are very tough to eradicate and microorganisms cause various infections. In this study, the anti-biofilm and antibacterial activities of extract Rosmarinus officinalis were examined. Materials and Methods: Bacterial strains were obtained from standard laboratory and growth and biofilm formation of strains were determined by microtiterplate method. Rosemary extracts were prepared by maceration. Results: The levels of MIC was observed ranges from 3.1 to 12.5 ppm. The highest MIC value was observed against Streptococcus pyogenes, Streptococcus pneumoniae and Staphylococcus saprophyticus and The minimum MIC value of rosemary extract concentration in 1/3 ppm that against Staphylococcus aureus. The results of this study showed that the rate of absorption (OD) for biofilm formation of Staphylococcus aureus and Streptococcus pneumoniae in concentrations ppm50 and ppm100 rosemary extract to zero value. Conclusion: Results of this study suggest that the extract of Rosmarinus officinalis may be useful alone to treat bacterial infections.