Extraction, characterization and antioxidant property of chitosan from cuttlebone Sepia kobiensis (Hoyle 1885)

Chitin was extracted from the cuttlebone of Sepia kobiensis and chitosan was prepared through deacetylation. The chitosan was characterized for its structural, physical and thermal (CHN, DDA, FT-IR, NMR, XRD, Viscometric analysis, SEM and DSC) properties. Further, the chitosan exhibited the antioxidant activity of 50.68-74.36% at 1-10 mg ml−1 and it also showed the reducing power of 0.28% at 1 mg ml−1. At 10 mg ml−1, the chitosan exhibited the scavenging ability of 46.17%, on 1,1-diphenyl-2-picrylhydrazyl radicals, 23.38-73.70% on superoxide radicals at 0.05-1.6 mg ml−1 and 18.34% to 62.39% (0.1-3.2 mg ml−1) on hydroxyl radicals; whereas at 1-10 mg ml−1 the chelating ability on ferrous ions was calculated as 49.74-73.59%. Based on the potential antioxidant activity, scavenging ability on hydroxyl radicals and chelating abilities on ferrous ions, the chitosan from the cuttlebone of S. kobiensis may not only be used as a potent natural antioxidant but also as a possible food quality enhancer ingredient in the pharmaceutical industry.