The Effect of Deacetylation of Chitin and Chitosan on Wound Healing in Rats

ABSTRACT

Chitin and chitosan, polysaccharides made up of polymeric N-acetly glucosamine and D-glucosamine, are widely found in nature, forming the skeletons of crustaceans and insects, as well as the components of bacteria cell walls. Chitin and chitosan have been known to have many useful biological properties such as biocompatibility, biodegradability, antimicrobial activity, and wound healing. There properties have been known to be different depending on the degree of deacetylation of chitin, but it has not yet been fully evaluated. The purpose of this study was to evaluate the wound healing effect by the degree of deacetylation. Full-thickness skin incision was made on the backs of Sprague-Dawley rats. Three concentrations of powder, comprising 90% chitin, 50% chitin and 10% chitin, were separately embedded in the wounds of 3 rat groups. The wound-breaking strength and the collagen-hydroxyproline content of the skin at the wound sites were measured and histological examination was performed at postoperative 3, 7, and 10 days. The 50% chitin group had the highest tensile strenght of all groups. But the 50% chitin and 90% chitin groups had the lowest collagen hydroxyproline levels among all groups. The wounds treated with 50% chitin powder were completely reepithelialized and granulation tissue in the wound was observed 7 days after initial wounding. The arrangement of collagen fibers in the skin was ordered and similar to normal skin The 50% chitin powder is considered to be the most efficient wound healing accelerator among different concentrations of chitin powder.