ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Radical-scavenging activity of glutathione, chitin derivatives and their combination‡

Katarína Valachová, Tamer Mahmoud Tamer, Mohamed Mohy Eldin, and Ladislav Šoltés

^aLaboratory of Bioorganic Chemistry of Drugs, Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Dúbravská cesta 9, 84104 Bratislava, Slovakia

E-mail: katarina.valachova@savba.sk

Abstract: Since chitosan and its amino-, cinnamo- or cinnamo-amino- derivatives are acid-soluble, the effect of acetic acid on hyaluronan (HA) macromolecules degraded by Cu(II) ions and ascorbate was examined to produce reactive oxygen species (ROS). Further, the effects of glutathione (GSH), chitosan and its derivatives, added individually or in combination, on the quenching of ROS and ABTS^•+ cation radical were examined using rotational viscometry and ABTS assay, respectively. The results of the rotational viscometry indicated a rapid degradation of HA by ROS after the addition of acetic acid. Chitosan and its derivatives moderately decreased the rate of HA degradation, while GSH decreased the rate of HA degradation more significantly. Moreover, GSH enhanced the protection of HA macromolecules against their degradation in the presence of chitosan or its derivatives. The results of the ABTS assay confirmed the results of the rotational viscometry. The GSH in the combination with chitosan and its derivatives reduced ABTS^•+ more intensively than when added individually.

Keywords: ABTS assay – glycosaminoglycans – polysaccharides – radical-scavenging activity – thiols – wound-healing

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2016-0011

Chemical Papers 70 (6) 820–827 (2016)