Structure and Anticoagulant Activity of a Galactofuranose-Containing Sulfated Polysaccharide from the Green Seaweed, Codium isthmocladum

A water-soluble sulfated polysaccharide, F2-1, was obtained from the marine green alga, Codium isthmocladum, using ion-exchange and size-exclusion chromatography. Structure analysis showed that the F2-1 was a sulfated arabinan comprising Ara, Rha, Man, Gal, and Xyl with an 18% sulfate content and a molecular weight of 100 kDa. Methylation analysis combined with desulfation, GC-MS, IR, and NMR spectroscopy showed that the backbone of F2-1 was -> 4)-beta-L-Arap(1 -> residue. Its 2-O and/or 3-O positions showed sulfate modification; additionally, the 2-O or 3-O position showed branch points. The side chains were composed of -> 5)-beta-D-Galf, (1 -> 2,6)-beta-D-Galf(1 ->, (1 -> 2)-beta-L-Rhap4S, -> 4)-alpha-D-Glcp(1 ->, and terminal alpha-D-Galp(1 -> and beta-D-Xylp(1 ->. Polysaccharides containing beta-D-galactofuranose are rarely found in seaweed. F2-1 exhibited significant anticoagulant activity in vitro. Our findings suggested that the green-tide alga, Codium isthmocladum, can be considered as a useful resource for bioactive polysaccharides.

Automated summary

A water-soluble sulfated polysaccharide, F2-1, was extracted from the marine green alga Codium isthmocladum. The polysaccharide showed significant anticoagulant activity and can be considered as a potential bioactive polysaccharide resource.