In vitro activity of chitosans in combination with antibiotics against pseudomonas aeruginosa and staphylococcus aureus
Date of Issue2010
School of Mechanical and Aerospace Engineering
Chitosan and its derivative water soluble chitosan oligosaccharide are used in a variety of applications in pharmaceutical preparations. In this study, 2 wild (ATCC 15729, PAOl) and 2 mutant strains (PT121, PT149) of Pseudomonas aeruginosa and one strain of MRSA Staphylococcus aureus (ATCC43300) are investigated for drug-drug interactions in vitro. Ten antimicrobial agents (antibiotics) are combined with different degree of deacetylated chitosans and chitosan oligosaccharide. All the chitosans exhibit synergistic activity with sulfamethoxazole against all P. aeruginosa strains. Chitosan oligosaccharide-sulfamethoxazole and high molecular weight chitosan-sulfamethoxazole combination are more effective than other chitosan preparations against S. aureus. Microscopic studies of bacteria cell membrane show evidence of the collapse of membrane integrity after treating with the combined drugs. This suggests the membrane disruption function of the chitosan and disruption of cell membrane synthesis function of sulfamethoxazole act synergistically. In conclusion, chitosan and chitosan oligosaccharide are effective against both gram-negative and gram-positive bacteria in combination with sulfamethoxazole.
Nanyang Technological University