Farnaz Yousefi - MSC, Department of Microbiology, Urmia Branch, Islamic Azad University, Urmia, Iran
Maryam Parvini Kohneshahry - Assistant Professor, Department of Microbiology, Urmia Branch, Islamic Azad University, Urmia, Iran
Ali Soldozi - Associate Professor, Department of Chemistry, Urmia Branch, Islamic Azad University, Urmia, Iran
Javid Taghinejad - Department of Microbiology, Malekan Branch, Islamic Azad University, Malekan, Iran

Background and aim: Oxadiazoles are heterocyclic compounds whose medicinal nature has been proven in a wide range of biological activities. Also, studies have shown that the presence of different halogen groups leads to different antimicrobial activity in Oxadiazole derivatives. The purpose of this study is to investigate the antimicrobial activity of compounds derived from Oxadiazole on some Gram-positive, Gram-negative bacteria and fungi. Materials and method: First, different Oxadiazole compounds were synthesized and their antimicrobial effect on standard Gram-positive, Gram-negative bacteria and yeast was investigated. For this purpose, successive dilutions of each of the derivatives were prepared in a Nutrient broth culture medium. Finally, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were evaluated using McFarland's standard solution. Results: According to the obtained results, the highest amount of non-growth halo was related to Gram-positive bacteria Staphylococcus aureus, Bacillus subtilis and Bacillus cereus respectively. Also, the lowest amount of non-growth halo was related to Listeria monocytogenes, Streptococcus pyogenes, Pseudomonas aeruginosa and Escherichia coli bacteria, which did not form a halo in these cases. Also, the results of examining the minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the synthesized compounds showed that Gram-negative bacteria are more resistant to synthetic compounds compared to Gram-positive bacteria. Conclusion: The results of this study showed that the synthesized Oxadiazole compounds had a favorable effect on Gram-positive bacteria. Due to the high antimicrobial properties of these compounds against Gram-positive bacteria, these compounds can be used as effective antibiotics against Gram-positive bacteria.

Antimicrobial activity, Gram positive bacteria, Gram negative bacteria, Oxadiazole derivatives, yeast