Abstract

The need to turn seafood wastes that hitherto constitute an environmental pollution into important pharmaceutical excipients is gaining ground worldwide. This study investigated the extraction and characterization of chitosan from two oyster shells: Mytilus edulis and Laevicardium attenuatum from different continents. Demineralization and deproteinization were carried out to obtain chitin from the shells, followed by deacetylation to obtain chitosan. Percent yield, degree of deacetylation and other physicochemical characteristics were determined for the extracted chitosan from the two oyster shells. The yield of chitosan from Mytilus edulis was 51.8% and 43.8% from Laevicardium attenuatum. The degree of deacetylation (DD) of chitosan from Mytilus edulis was 69.6% while that of Laevicardium attenuatum was 37.3%. The Laevicardium attenuatumchitosan had higher swelling ratio. Calcium was the predominant metal ion in the two chitosan. While the micrograph of Mytilus edulis chitosan showed a non-uniform particle distribution, Laevicardium attenuatum chitosan showed a brick-like structure. This work has shown that it is more economical to produce chitosan from Mytilus edulis, and the polymer has higher degree of deacetylation. The higher degree of deacetylation implies better solubility and the chitosan could be more suitable as a permeation enhancer. The Laevicardium attenuatumchitosan could be more suitable for sustained release formulation.

Keywords: Chitosan, Mytilus edulis, Laevicardium attenuatum, Oyster Shells