Evalution and Molecular Docking of Benzimidazole and its Derivatives as a Potent Antibacterial Agent

Abstract

The study was performed to identify a potent antibacterial benzimidazole derivative using in vitro and in silico techniques. Benzimidazole and its derivatives were synthesized by reflux process. The derivatives were screened for antibiotic susceptibility test (AST) and minimum inhibitory concentration (MIC) against Gram-negative and Gram-positive clinical isolates and compared with the positive control Norfloxacin. Insilico molecular docking was performed to screen the binding potential of the derivatives with target enzymes topoisomerase II /DNA gyraseof Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) along with the control Norfloxacin.Totally fifty-four isolates were screened for antimicrobial supectibility test (AST) and minimum inhibitory concentration (MIC) and 35 clinical isolates of Gram-negative showed 86% resistance to Norfloxacin and 19 isolates of Gram-positive showed 90% resistance to Norfloxacin. However, these isolates were found to be sensitive to 1-(4-((1H–benzimidazol-1-yl) methylamino) phenyl) ethanone (3) (C2), and 2-methyl-1H-benzimidazole (C4) compounds, with MIC ranges from 6.25- 12.5 µg/ml. Molecular docking analysis revealed that the compound C2 exhibited better binding affinity towards topoisomerase II / DNA gyrase of E.coli and S.aureus when compared with C4 and control Norfloxacin. The antibacterial activity of these may due to the inactivation of these enzymes which is supported by the MIC results.The obtained in vitro and in silico results suggested that C2 showed better antimicrobial activity.