Eradication of biofilms formed by bacteria isolated from diabetic foot infections by potential antibiofilm agents alone and in combination with ciprofloxacin

Abstract

This study was performed to investigate the resistance of biofilm forming bacteria isolated from diabetic foot infection to different antibiotics and the eradicating activity of some potential antibiofilm agents alone and in combination with ciprofloxacin. Imipenem was the most active against biofilms formed by all tested strains, while tetracycline was the least active. For biofilms of Gram-positive bacteria, azithromycin and imipenem were the most potent, while tetracycline and vancomycin showed the lowest activity. Similarly, imipenem showed the highest activity against biofilms of Gram-negative bacteria, while ciprofloxacin, tetracycline and cefoperazone were the least active. Potential antibiofilm agents exerted antibacterial and biofilm eradicating activities. Apple and grape vinegars showed the highest activities, followed by estradiol, ambroxol and piroxicam. Dexamethasone, manuka and citrus honeys were less active. Ambroxol showed the highest synergistic activity with ciprofloxacin, followed by dexamethasone, manuka honey, piroxicam, estradiol and grape vinegar, while apple vinegar and citrus honey showed intermediate activity. In conclusion, this study recommends the use of antibiofilm agents in combination with antibiotics to combat the resistance of biofilms to antibiotics. Key words: Diabetic foot infections, biofilm eradication, antibiofilm agents, ciprofloxacin, synergy.