Structure and properties of carrageenan-like polysaccharide from the red alga Tichocarpus crinitus (Gmel.) Rupr. (Rhodophyta, Tichocarpaceae)

摘要

Sulfated polysaccharides occurring in the red algae Tichocarpus crinitus cell wall were fractionated and purified. NMR and FT-IR spectroscopy analyses revealed that the non-gelling fraction contained a sulfated galactans having a new carrageenan-like structure. It is built with alternatively linked 1,3-linked β-D-galactopyranosyl-2,4-disulphates and 1,4-linked 3,6-anhydro-α-D-galactopyranosyl residues. Minor amounts of its biosynthetic precursor were detected in a water-extracted specimen. Brief analysis of rheological and biological properties of the non-gelling fraction was carried out. The carrageenan-like polysaccharide from T. crinitus displayed the properties of “random coil” polymer at high temperature, and possesses high anticoagulant activity at low concentration.