Tabriz University of Medical Sciences Medical Journal of Tabriz University of Medical Sciences 2783-2031 35 6 2014 02 05 The Study of Antibacterial Activity of Alcoholic Extract of Brassica Napus L. On Some of Pathogenic Bacteria 74 79 EN Hadi Alizadeh Mehdi Ghiamirad Saeideh Ebrahimiasl Journal Article 2013 09 01 2013 11 04 Background and Objectives: As the awareness about the dangerous side effects of synthesis antibiotics is growing, the request for natural alternatives of these drugs has been increased. Natural materials reduce the danger of these side effects. Brassica Napus L. is a medicinal plant which has diverse applications in traditional medicine. This study aims to investigate the antibacterial effects of Brassica Napus L. alcoholic extract on some of pathogenic bacteria. Materials and Methods: In this experimental study, the turnip with scientific name of Brassica Napus L. has been used. Having prepared the alcoholic extract, the effect of 50mg/ml, 100 mg/ml, 200 mg/ml and 400 mg/ml of this extract were studied using well diffusion agar and disk diffusion agar on Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa bacteria. The test of defining the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) was done using serial tube dilution. Results: The Brassica Napus L. alcoholic extract prevented the growth of Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa bacteria. The Minimum Inhibitory Concentration from the growth of this bacteria ranges from 12.5 mg/ml to 100 mg/ml. Conclusion: The Brassica Napus L. alcoholic extract has significant inhibitory role in the growth of pathogenic bacteria in vitro. Meanwhile, more researches are recommended due to reaching more inclusive results.