M Heidart Sureshjani - Department of Food Science and Technology, Ferdowsi University of Mashhad, Iran
F Tabatabaei Yazdi - Department of Food Science and Technology, Ferdowsi University of Mashhad, Iran
A Mortazavi - Department of Food Science and Technology, Ferdowsi University of Mashhad, Iran
F Shahidi - Department of Food Science and Technology, Ferdowsi University of Mashhad, Iran

According to biologically active compounds and traditional use of the Satureja bachtiarica, seem that this plant has significant antimicrobial effects. In this study antimicrobial effect of extracts evaluated by two methods, Collins method and disk agar diffusion method on Escherichia coli PTCC 1330 and Staphylococcus aureus PTCC 1337 microorganisms. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for both species determined by using a dilution method. Statistical analysis was carried out by analysis of variance (ANOVA). All ethanolic extract concentrations had an inhibitory effect on the disk agar diffusion method. In Collins method ethanolic extract in 2000 μg/ml concentration, could prevent the growth of both strains on medium. The aqueous extract, had no antimicrobial significant effect in 2000 μg/ml concentration. The ethanolic extract MIC of Satureja bachtiarica for Staphylococcus aureus was 8 mg/ml, and for Escherichia coli was 16 mg/ml. But the aqueous extracts MIC of Satureja bachtiarica for Staphylococcus aureus was 32 mg/ml and for Escherichia coli was 64 mg/ml. The ethanolic extract MBC of Satureja bachtiarica for Staphylococcus aureus was 16 mg/ml, and for Escherichia coli was 32 mg/ml. But the aqueous extracts MBC of Satureja bachtiarica for Staphylococcus aureus was 64 mg/ml and for Escherichia coli was 256 mg/ml. The Satureja bachtiarica extract presented the more effective impact on the growth of Staphylococcus aureus PTCC 1337 than Escherichia coli PTCC 1330 (p<0.05). The results indicate that ethanolic extract of Saturejabachtiarica has the greatest effect on gram positive bacteriumStaphylococcus aureus PTCC 1337

Satureja bachtiarica, Escherichia coli, Staphylococcus aureus, Antimicrobial