A study on the extraction of chitin and chitosan from the invasive sea urchin Diadema setosum from Iskenderun Bay in the Northeastern Mediterranean

Abstract

This work presents, for the first time, the extraction and characterization of chitin and chitosan from the testa (T) and spines (S) of the invasive sea urchin (Diadema setosum) from the İskenderun Bay in the Northeastern Mediterranean. Testa chitin (T-CT), spine chitin (S-CT), testa chitosan (T-CS), and spine chitosan (S-CS) were isolated following demineralization, deproteinization (chitin), and deacetylation (chitosan). The yield of chitin extraction from dry sea urchin testa (T-CT) and spines (S-CT) were 57.2 ± 1.43% and 67.1 ± 0.17%, respectively. The yield of chitosan produced from extracted testa (T-CS) and spines (S-CS) chitin were 87.3 ± 1.82% and 74.04 ± 1.27%, respectively. Degree of deacetylation (DD%) value were calculated using FT-IR (84.19% and 85.80%), resulting in a high DD. They were perfectly soluble in acidic solution. We also characterized the isolated chitin (T-CT and S-CT) and chitosan (T-CS and S-CS) by determining its physicochemical properties using X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscope analysis (SEM). Overall, the results indicated that the preparation of chitin and chitosan from the invasive sea urchin testa and spines could open the opportunity for the value-added seafood waste to be utilized in a wide range of practical applications such as medicine, pharmaceutical, and biotechnology.