Structural characterization and antiviral activity of two fucoidans from the brown algae Sargassum henslowianum

Carbohydr Polym. 2020 Feb 1;229:115487. doi: 10.1016/j.carbpol.2019.115487. Epub 2019 Oct 20.


Purified fucoidans SHAP-1 and SHAP-2 with apparent molecular weights of 6.55 × 105 and 5.89 × 105, respectively, were isolated from Sargassum henslowianum by ion-exchange and gel-filtration column chromatography. They are both composed of fucose and galactose at a ratio of around 3:1 and 31.9% sulfate. The backbone of two fucoidans consists of α-(1→3)-linked L-Fucp residues which are mainly sulfated on the C-2 and C-4 positions. Side chains composed of terminally linked α-L-Fucp and α-D-Galp residues, and (1→2)-, (1→6)-, and (1→2,6)-linked β-D-Galp residues attach mainly at O-4 position of backbone residues. Antiviral test showed that the IC50 values of SHAP-1 and SHAP-2 against HSV-1 were estimated to be 0.89 and 0.82 μg/mL by plaque reduction assay, respectively, whereas both as low as 0.48 μg/mL against HSV-2. The antiviral mechanism of the fucoidans might be at least through blocking HSV-2 virion adsorption to host cells. These results suggest that the fucoidans have potential clinical applications.

Keywords: Antiviral; Brown algae; Fucoidans; Herpes simplex virus; Sargassum henslowianum.

MeSH terms

  • Antiviral Agents / chemistry*
  • Antiviral Agents / pharmacology*
  • Herpesvirus 1, Human / drug effects
  • Herpesvirus 2, Human / drug effects
  • Polysaccharides / chemistry*
  • Polysaccharides / pharmacology*
  • Sargassum / chemistry*


  • Antiviral Agents
  • Polysaccharides
  • fucoidan