Anti-microbial Activities of <em>Pseudomonas</em> Metabolites Methanolic Extracts against Different MDR Bacterial Pathogens

Abstract

Background: A Multiple drug resistance (MDR) in pathogenic bacteria has become a significant public health issue for treatment. Among bacteria, Pseudomonas is another important genus except Streptomyces and Bacillus in production of antimicrobial compounds. The current study aim to to determine the antibacterial activity and preliminary characterization of antibacterial compounds produced by Pseudomonas species such as BB1D11, BN2D41, TG1D11, TR1D41, LH1D11 and TN1D41. Method: The antibacterial activity was checked by using bio autography method as well as agar well diffusion method, against four multiple drug resistant bacteria including three Gram negative bacteria (E.coli, Acinetobacter and Pseudomonas) and one Gram positive bacterium (Methicillin Resistant Staphylococcus aureus). Isolation test showed good activity against all the four MDR bacteria, by producing clear zone of diameter from 2mm up to 20mm. Optimum temperature for growth and antibiotic production of Pseudomonas BB1D11, BN2D41, TG1D11, TR1D41, LH1D11 and TN1D41 was 37C0. It produces more metabolites when subjected to shaking incubation. In thin layer chromatography, the extracts were repeatedly inserted on a silica gel coated plate, which was run in mobile phase. Normal HPLC was perform to reveal the presence of antibacterial compounds. Results: By well diffusion assay a zone of inhibition range from 2-18 mm of diameter against different test bacteria. The components were separated, resulting in the formation of bands with different colors, each showing a different compounds. Biological screening was performed by bio autography, metabolites showed a significant activity at retention factor of 0.89. While HPLC at retention time 2.50-2.90 showed presence of significant antibacterial compounds. Conclusion: Pseudomonas BB1D11, BN2D41, TG1D11, TR1D41, LH1D11 and TN1D41 showed promising anti-microbial activity against different MDR bacteria. It is concluded that HPLC revealed the presence of DAPG at retention time 2.90 which inhibit the growth of MDR bacterial strains.