Purification and characterization of fucose-containing sulphated polysaccharides from Sargassum tenerrimum and their biological activity

The crude sulphated polysaccharides (ST-D) were extracted from Sargassum tenerrimum and purified using DEAE-Sepharose anion-exchange chromatography and yielded three fractions (ST-DFI 46.2% ( w / w ), ST-DFII 51.6% ( w / w ) and ST-DFIII 2.2% ( w / w )). The monosaccharide composition analysis showed fucose (40–43%) as the major sugar. The apparent molecular weight of ST-DF1, ST-DFII and ST-DFIII was found to be 233, 286 and 88 kDa, respectively. Structural investigation analysis by FTIR and NMR revealed the presence of sulphated polysaccharides with (1,3)-linked fucose with sulphation at C4 and C2 position. The ST-DFIII was the most biologically active fraction. It had the highest anticoagulant (APTT 265 ± 2.7 s) and radical scavenging activity (superoxide radical IC 50 26.1 ± 0.15 μg mL −1 ). ST-DFII was slightly less active than ST-DFIII but could be obtained in higher quantity. These results suggest that ST-DFII from S. tenerrimum could become a promising entity as nutraceutical molecule.