Metalloantibiotics: Synthesis, characterization and antimicrobial evaluation of bismuth-fluoroquinolone complexes against Helicobacter pylori

Pharmacy Department, Faculty of Technology and Engineering, The M. S. University of Baroda, Vadodara-390001, India.
Acta Pharmaceutica (Impact Factor: 0.91). 09/2009; 59(3):259-71. DOI: 10.2478/v10007-009-0027-6
Source: PubMed


Novel organometallic compounds have been prepared by complexing the fluoroquinolones, norfloxacin, ofloxacin, ciprofloxacin, sparfloxacin, lomefloxacin, pefloxacin and gatifloxacin, with bismuth. The complexes were characterized by UV, IR, atomic absorption spectroscopy, elemental analysis, differential scanning calorimetry, thermogravimetric analysis and mass spectrometry. Their antibacterial potential against Helicobacter pylori and other microorganisms was investigated. These compounds were found to possess strong activity against Helicobacter pylori with a minimum inhibitory concentration of 0.5 mg L-1. They also exhibited moderate activity against Escherichia coli, Staphylococcus aureus, Bacillus pumilus and Staphylococcus epidermidis. These bismuth-fluoroquinolone complexes have the potential to be developed as drugs against H. pylori related ailments.

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    • "LFX-metal complexes were found to exhibit enhanced activity on bacterial or fungal growth compared to free LFX activity (Mohamed et al, 2011). Organmetallic complex of LFX with bismuth has been prepared and their antibacterial potential against H. pylori was more potent (lower MIC) compared to the free LFX (Shaikh et al, 2009). The increased activity of LFX complexes can be related to the enhanced lipophilicity of complexes which leads to breakdown of the permeability barrier of the bacterial cell (Mohamed et al, 2011). "
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