succinic acid into chitosan remarkably increases the oxygen sorption rate onto both chitosan flakes and chitosan beads (Fig. 6), compared to that onto untreated chitosan. Analysis of antimicrobial activity demonstrated that chitosan modified by succinic acid decreased the viability of E. coli by a factor of 50 as compared to that of reference. It should be mentioned that the onset of bacterial growth in water samples containing such chitosan was observed only after 30 days of incubation