RHAMNAN SULFATE FROM CELL-WALLS OF MONOSTROMA-LATISSIMUM

Rhamnan sulfate from cell walls of Monostroma latissimum was purified through subsequent chromatographic systems. The purified polysaccharid e consisted of large amounts of rhamnose residues and appeared to be a n entire homopolysaccharide. Antithrombin activity was lower than rham nan sulfate previously obtained from M. nitidum but similar to standar d heparin. Studies of the major structural parts of the rhamnan sulfat e by periodate oxidation, Smith degradation and permethylation, showed it to consist of 1,3- and 1,2 linked rhamnose residues in a ratio of 3:2. Sulfate was mainly substituted at C-3 or C-4 in the 1,2-linked rh amnose residue. The detection of oligosaccharides by matrix-assisted l aser desorption/ionization time-of-flight mass spectrometry supports t his structure. These results suggested that rhamnan sulfate from the M onostromaceae has quite different structural properties from ulvan fro m the Ulvaceae. (C) 1998 Elsevier Science Ltd. All rights reserved.