Int J Biol Sci 2009; 5(2):153-160. doi:10.7150/ijbs.5.153 This issue

Research Paper

Activity of Chitosans in combination with antibiotics in Pseudomonas aeruginosa

San Tin1,2, Kishore R. Sakharkar1,3, Chu Sing Lim1,2, Meena K. Sakharkar1,2 ✉

1. Biomedical Engineering Research Centre, Nanyang Technological University, Singapore
2. Advanced Design and Modeling Lab, Nanyang Technological University, Singapore
3. OmicsVista, Singapore

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Tin S, Sakharkar KR, Lim CS, Sakharkar MK. Activity of Chitosans in combination with antibiotics in Pseudomonas aeruginosa. Int J Biol Sci 2009; 5(2):153-160. doi:10.7150/ijbs.5.153. Available from

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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 and PAO1) and 2 mutant strains (PT121 and PT149) of P. aeruginosa are investigated for drug-drug interactions in vitro. 10 antimicrobial agents (antibiotics) are combined with different degree of deacetylated Chitosans and Chitosan oligosaccharide. All the chitosans show synergistic activity with sulfamethoxazole, a sulfonamide antimicrobial agent. It is interesting to observe that the MIC value for the MexEF-OprN overexpressing mutant strain of P. aeruginosa is 5 fold higher than the other strains under investigation suggesting a possible role of this efflux pump in Sulfamethoxazole efflux. The findings suggest on the use of chitosans as enhancing agent in combination with antibiotics in pharmaceutical preparations.

Keywords: Synergy, additive, combination therapy, Chitosan, chitin, drug resistance.