Chitosan has found wide application in the biomedical field due to its interesting biological properties that include: biocompatibility, biodegradability, hemostatic activity and bacteriostatic effect. In this present study, antibacterial activity of chitosan solutions for wound dressing were investigated against Stophylococcus aureus (isolated from an activated sludge) and Escherichia coli (ATCC 25922) that are potential wound pathogens. Moreover, the effects of plasticizer addition and chitosan concentration on antibacterial activity of chitosan solutions were also evaluated. According to the antibacterial activity study, chitosan solutions, plasticized or not, showed inhibitory activity against Escherichia coli. However, they did not inhibit Staphylococcus aureus growth, possibly because this bacterium strain would become resistant due to mutations caused by industrial effluent exposure. Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA.245-246 515518Kurita, K., (1998) Polym. Degrad Stabil, 59, p. 117Berger, J., (2004) Eur. J. Pharm. Biopharm, 57, p. 19Hoemann, C., (2005) Osteoarthr. Cartilage, 13, p. 318Denkbas, E., (2004) J. Biomater. Appl, 18, p. 291Ueno, H., (2001) Adv. Drug Deliver Rev, 52, p. 105Helander, I.M., (2001) Int. J. Food Microbiol, 71, p. 235Bowler, P.C., (2001) Clin. Microbiol. Rev, 14, p. 244Uri, J.V., (1994) Acta Microbiol. Immunol. Hung, 41 (2), p. 215Suyatma, N., (2005) J. Agr. Food Chem, 53, p. 3950Liu, H., (2004) Int. J. Food Microbiol, 95 (2), p. 147