The antibacterial activity of the water extracts of three species of Salvia on Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa

The aim of this study was to evaluate the antibacterial activity of the water extracts of three species of Salvia (S. perspolitana, S. palaestina, S. bracteata) on Staphylococcus aureus, Escherichia coli and Pseudomonas aeroginosa. The antibacterial activity of water extracts of the studied species on the bacterial strains was examined using well diffusion method and minimum inhibitory concentration (MIC). Results showed that only S. bracteata formed growth inhibitory zone (9 mm) on Staphylococcus aureus. The extracts of all three plants formed growth inhibitory zone on E.coli and P. aeroginosa. The extract of S. bracteata was more effective than that of the other species. Results for MIC also showed that the extracts of S. perspolitana had the lowest effect on St. aureus and its MIC was observed in a concentration of 1024 µg/ml. The extracts of this species had the inhibitory effect in a concentration of 256 µg/ml. The uppermost inhibitory effect was provided by the extract of S. bracteata, since the minimum inhibitory concentration of this species for S. aureus was equal to 64 µg/ml; and for the other two bacteria, it was equal to 128 µg/ml. The extracts of S. palaestina had the lowest effect on S. aureus and its MIC was observed in a concentration of 1024 µg/ml. The extracts of this species had an MIC equal to 512 µg/ml for the other two bacteria. It was concluded that S. bracreata could be considered a suitable species with anti-bacterial activities in future researches.