Physicochemical and biological activities of polysaccharides from the waste residue of sea cucumber peptide production

This study was to investigate the physicochemical and biological activities of sea cucumber polysaccharides extracted from waste residue of peptide production (SCRP). The monosaccharide composition of SCRP was 20.03% mannose, 19.56% glucose, 18.63% galactose, 25.94% arabinose and 15.82% fucose with the Mw and Mn of SCRP of 57.5 and 51.3 kDa. The intrinsic viscosity of SCRP was 8.9 mL/mg with a liquid-like rheological behaviour. Two main endothermic peak temperatures of the SCRP sample were 85.03 and 231.80°C. SCRP rendered the early apoptosis of cells, as well as induced the loss of mitochondrial transmembrane potential and increase the reactive oxygen species (ROS) level with a concentration-dependence manner. The results implied that a by-product SCRP could be extracted from the waste residue during peptide production, and exhibited inhibitory effects against MDA-MB-231 cells.