تأثیر عصارۀ الکلی گیاهان بارهنگ و برگِ‌بو بر خواص ضد باکتری برخی از باکتری های گرم مثبت و منفی

Introduction: Antimicrobial activity of oils, plant extracts on various microorganisms has been reported from different areas. In the present study, we tried to exam the activity of Plantago major and Laurus nobilis extracts collected from Semnan province on some of gram-positive and gram-negative bacteria. Methods: This is an experimental study. Plantago major and Laurus nobilis extracts were prepared by soxhlet method. Antibacterial activity was evaluated by agar well diffusion. Average of inhibition zone diameter was recorded after triplicate repeat. Microplate titration was used for investigation of Minimum inhibitory concentration and Minimum bactericidal concentration. Spss software used for data analysis. Data are presented as frequency and percentage and mean and standard deviation. Results: The highest antibacterial activity of plant extract on gram positive bacteria was on Enterococcus faecium and Staphylococcus aureus, and Laurus nobilis extract had the most effect on Staphylococcus aureus bacteria. The lowest concentration of alcoholic extract of Laurus nobilis and Plantago plants that stop the growth of Staphylococcus aureus was 100 mg / ml, with a halo diameter of 13 mm. Conclusion: The most antibacterial activity of plant extract was detected against Staphylococcus aureus and Enterococcus faecium and the highest antibacterial activity of Leaf extract against Staphylococcus aureus was obtained.