Presence of potent inhibitors of bacterial biofilm associated proteins is the key to Citrus limon’s antibiofilm activity against pathogenic Escherichia coli

Abstract

In an era of antibiotic resistance where natural antibiotic substitutes are considered essential, the antimicrobial and antibiofilm activities of Citrus limon extract on strains of pathogenic Escherichia coli isolated from pork were evaluated. The strains which form biofilms were more resistant (MIC₅₀ = 2.5 mgml⁻¹) compared to non-biofilm forming strains (MIC₅₀ = 1.25 mgml⁻¹). Use of C. limon extract at 20 mgml⁻¹ concentration has resulted in inhibition of biofilm formation by 53.96%. Cyclobarbital, 5, 8-dimethoxycumarin, orotic acid and 3-methylsalicylhydrazide were the major phytochemicals in C. limon extract with highest docking affinities against the biofilm associated proteins in E. coli. The results of simulation studies have clearly illustrated the energy stability of the protein-ligand complexes. Absorption, distribution, metabolism, excretion and toxicity (ADMET) profiles revealed that the phytochemicals in C. limon could be used in the drug design studies to preferentially target the specific receptors to combat biofilms associated with E. coli.

Keywords:

• Citrus limon
• phytochemicals
• biofilm
• Escherichia coli
• molecular docking

Acknowledgement

The authors wish to thank Indian Council of Agricultural Research for the financial assistance to undertake this work.

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.