Structural features and anti-HIV-1 activity of novel polysaccharides from red algae Grateloupia longifolia and Grateloupia filicina

• Published in: International journal of biological macromolecules 2007-10, Vol.41 (4), p.369-375
• Main Authors: Wang, S.C., Bligh, S.W.A., Shi, S.S., Wang, Z.T., Hu, Z.B., Crowder, J., Branford-White, C., Vella, C.
• Format: Article
• Language: English
• Subjects: Antiviral Agents - pharmacology; Antiviral Agents - toxicity; Cell Survival - drug effects; Cells, Cultured; Chromatography, Gel; Cytotoxicity; Galactans - chemistry; Galactans - isolation & purification; Galactans - pharmacology; Grateloupia; Grateloupia filicina; HIV-1 - drug effects; Human immunodeficiency virus 1; Inhibitory Concentration 50; Leukocytes, Mononuclear - drug effects; Leukocytes, Mononuclear - virology; Molecular Weight; Nuclear Magnetic Resonance, Biomolecular; Polysaccharides - chemistry; Polysaccharides - isolation & purification; Polysaccharides - pharmacology; Polysaccharides - toxicity; Potent HIV-1 inhibition; Rhodophyta - chemistry; Spectrophotometry, Infrared; Sulfur Compounds - chemistry; Sulphated galactans; Virus Replication - drug effects
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2007.05.008

Since sulphated polysaccharides have antiviral activity in vitro, we examined the structure and antiretroviral activity of native sulphated galactans extracted from the red algae, Grateloupia filicina (GFP) and Grateloupia longifolia (GLP). The sulphate contents of GFP and GLPE (the 1,4-α- d-glucan-glucanohydrolase digest of GLP) were 25.7 and 18.5%, respectively. The sulphate ester groups were located at carbon 2 for GFP and at carbon 2 and 6 for GLPE. Antiretroviral activity was investigated with a primary isolate (PI) of HIV-1 and human peripheral blood mononuclear cells (PBMCs) rather than T-cell line adapted (TCLA) HIV-1 and T-cell lines because it is more representative of the in vivo situation. Both compounds and their derivatives had potent anti-HIV-1 activity when added at the time of infection, and 2 h post-infection (EC 50s 0.010–0.003 μM, EC 90s 0.87–0.33 μM) and low cytotoxicity. Their potential medical application as virucidal vaginal formulations is discussed.