Annual variation in composition and in vitro anti-HIV-1 activity of the sulfated glucuronogalactan from Schizymenia dubyi (Rhodophyta, Gigartinales)

An account is given of the annual variation in composition and in vitro anti-HIV-l activity of the water-soluble sulfated glucuronogalactan from Schizymenia dubyi collected in Sicily. No marked variation seasonal chemical or physico-chemical features was observed, with the exception of L-galactose residues and viscosity. Evaluation of the anti-HTV-1 effect of the polysaccharide indicated that syncitial formation and HIV-associated reverse transcriptase in vitro were completely suppressed at 5 mu g ml(-1) by alga collected during the summer/spring period. This high anti-HIV-1 activity corresponded with a decrease in L-galactose, viscosity and sulfate content of the polysaccharide.