Polysaccharides from Sargassum tenerrimum: Structural features, chemical modification and anti-viral activity

Herpes simplex viruses (HSVs) display affinity for cell-surface heparan sulfate proteoglycans with biological relevance in virus entry. Here, we exploit an approach to inhibiting HSV infection by using a sulfated fucoidan, and a guluronic acid-rich alginate derived from Sargassum tenerrimum, mimicking the active domain of the entry receptor. These macromolecules have apparent molecular masses of 30 +/- 5 and 26 +/- 5 kDa, respectively. They and their chemically sulfated derivatives showed activity against herpes simplex virus type 1 (HSV-1). Their inhibitory concentration 50% (IC50) values were in the range 0.5-15 mu g/ml and they lacked cytotoxicity at concentrations up to 1000 mu g/ml. The anti-HSV activity increased with increasing sulfate ester content. Our results suggest the feasibility of inhibiting HSV infection by blocking viral entry with polysaccharide having specific Structure. (C) 2009 Elsevier Ltd. All rights reserved.