Sulfated polysaccharides from Laminaria angustata: Structural features and in vitro antiviral activities

► Two series of sulfated polysaccharides have been generated from Laminaria angustata. ► Sulfated xylogalactofucan has higher potency than the sulfated alginate. ► These macromolecules inhibit viral adsorption/attachment to cells. ► Sulfate content seemed to be important hallmark of their anti-HSV activity.