Characterization and assessment of antioxidant and antibacterial activities of sulfated polysaccharides extracted from cuttlefish skin and muscle

Abstract

In this study, novel polysaccharides extracted from cuttlefish skin (CSP) and muscle (CMP), by precipitation with cetylpyridinium, were characterized and their antioxidant and antibacterial activities were investigated. CMP showed the highest amounts of sulfated groups (6.6%), uronic acids (9.2%) and proteins (3.7%). Infrared spectroscopic analysis indicated the presence of sulfonyl (OSO) and acetyl (CH3CO−) groups for both CSP and CMP. In addition, CSP showed the presence of glucuronic acid (GlcA) and galacturonic acid (GalA) as major components, while CMP showed highest amount of GalA in its monosaccharide composition. Sulfated polysaccharides were found to display important antibacterial activity against several Gram+ and Gram− bacteria. In addition, they exhibited strong antioxidant activities as showed by various in vitro tests. Fractionation of cuttlefish polysaccharides, by DEAE-cellulose column showed one peak during the buffer elution phase and three major fractions for CMP and two peaks for CSP during the linear gradient of NaCl. The last eluting sulfated fraction from each sample, characterized by the highest negative charge, was found to exhibit the best antioxidant and antibacterial activities. The obtained results demonstrated that cuttlefish polysaccharides and their fractions could serve as natural antioxidant and antibacterial agents.