Investigation of antimicrobial activities of some fluorinated benzaldehyde derivative schiff base compounds

Multidrug resistant bacteria are a serious problem that has grown alarmingly in recent decades. There is an urgent need to identify ways to treat bacterial resistance because the emergence of resistant diseases caused by these germs has led to death and morbidity. In our study, we aimed to discover and find new antimicrobial drugs against microbes to resolve resistance and to evaluate the potential and efficacy of some fluorinated Schiff base compounds derived from benzaldehyde as antibacterial agents on the standard strains of Staphylococcus aureus Pseudomonas aeruginosa and Escherichia coli. At the beginning all of the bacterial strains have been reactivated in nutrient broth medium at 37 °C and for 24 h and all of the Schiff base compounds (C1-6) have been added into culture plates (96-well) in triplicate order at: 1, 10, 100 to 1000 μM doses. Reactivated Bacterial number adjusted at 0.5 McFarland standards, and then 100 μl added into each culture plate well, then was incubated at 37 °C and for 18 h after incubation, 10 μl of MTT dye (300 μM/ml concentration) have been added to each well and was incubated for 4 h eventually, 100 μl of dimethyl sulfoxide was added to each well, in order to dissolve formazan crystals. The optical density (OD) values for each well were recorded by an microplate reader at 570 nm and MIC50 value of any compound have been calculated through linear regression analysis. Gentamicin's MIC50 for E. coli, S. aureus and P. aeruginosa were found (2.14, 2.21, 2.19 μM, respectively). We found among six fluorinated phenylhydrazıne benzaldehyde compounds, C3 has most effective against E. coli (MIC50 value was 3.81 μM) C4 has most effective against S. aureus (MIC50 value was 3.45 μM) C6 has most effective against P. aeruginosa (MIC50 value was 3.31 μM).Our study could lead to the discovery of new antibacterial agent candidates which will benefit our country's drug industry and human health care. We believe that further testing of C3 for E. coli, C4 for S. aureus, and C6 for P. aeruginosa infections may result in important data for new drug research.