Physicochemical Characterization of Water-Soluble Chitosan Derivatives with Singlet Oxygen Quenching and Antibacterial Capabilities

NOELIA L. VANDEN BRABER,LADISLAO I. DÍAZ VERGARA,FAUSTINO E. MORÁN VIEYRA, CLAUDIO D.BORSARELLI, MARIANA M. YOSSEN, JORGE R. VEGA, SILVIA G. CORREA, MARIANA A. MONTENEGRO

INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2017

0141-8130

New water-soluble chitosan derivatives (WSCh) were obtained by Maillard reaction (MR) betweenglucosamine (GA) with both low and medium molecular weight chitosans (Ch). The WSCh showedlarger solubility than the respective Ch, while their deacetylation degree (DD) decreased byapproximately 12 %. Infrared spectroscopy experiments of WSCh confirmed the formation of iminebonds after MR with intensified pyranose structure, and sugar molecules as polymer branches.However, a 6-times reduction of the molecular weight of WSCh was measured, indicating thebreakdown of the polysaccharide chain during the MR. The polysaccharides quenched singletmolecular oxygen (1O2), with rate quenching constants correlating with the DD value of thesamples, suggesting the important role of amino groups (NH2) in the deactivation of 1O2.Additionally, all polysaccharides presented antimicrobial activity against pathogenic bacteria, e.g.Staphylococcus aureus, Escherichia coli, Salmonella sp., Enterococcus faecalis and Listeriaivanovii, as tested by their minimum inhibitory concentration (MIC). This way we obtained newwater-soluble polysaccharides, with similar functional properties to those presented by native Ch,enhancing its potential application as carrier material for bioactive compounds