Polysaccharides, sulfated

Similar instances, in which analytical data were of prime importance and where no products were isolated, are the oxidations of various di-D-fructose dianhydrides,80 inositols,81 the trisaccharide moiety of the alkaloid solamargine,82 2-O-a-L-fucopyranosyl-L-fucitol derived from fucoidin83 (a polysaccharide sulfate ester), trehalose and neotrehalose,84 maltotetraose,85 D-galactopyranosyl-glyceritol,86 and a 3-pentulose.87... 

The anticoagulant heparin is a polysaccharide sulfate which can form an electrostatic complex with blood-clotting factors (see ASIDE on blood clotting) and prevent the cascade from progressing. 

It is conceivable that a polysaccharide sulfate acts as the substrate in the mineralization of a protozoan group, the acantharid radiolaria, that deposit a celestite (SrS04) skeleton with small amounts of barite (BaS04) in solid solution295). Other polysaccharides are known with carbonate groups and they are likely candidates in carbonate deposition. Thus, a number of polysaccharides exist that can selectively... 

R. Takano, J. Hayashi, K. Hayashi, S. Hara, and S. Hirase, Structure of a water-soluble polysaccharide sulfate from the red seaweed Joculator maximus Manza, Bot. Mar., 39 (1996) 95-102. 

M. Matsuo, R. Takano, K. Kamei-Hayashi, and S. Hara, A novel regioselective desulfation of polysaccharide sulfates Specific 6-O-desulfation with N, 0-bis(trimethylsilyl)acetamide, Carbohydr. Res.,2A (1993) 209-215. 

E. Legendre, Etude par chromatographic d affinite liq-uide haute performance des interactions entre des pro-teines de la coagulation et des polysaccharides sulfates a activite anticoagulante immobilises sur des supports de silice enrobde, thesis. University Paris 13,1996. 

An investigation of polysaccharide sulfates has further demonstrated this particular application of infrared spectroscopy to the structural analysis of these compounds, but, at the same time, it serves to emphasize the need for the simultaneous observation of other properties. 

Finally, mention should be made of another kind of sulfatase, extracted from a red alga. This sulfatase is not a hydrolase, but converts residues of L-galactose 6-sulfate within a particular polysaccharide, porphyran, into 3,6-anhydro-L-galactose residues, thus simulating the action of alkali. It is not yet known whether this enzyme will function on suitably sulfated oligosaccharides, or whether it is specific for the polysaccharide sulfate, porphyran. 

Polysaccharide suMate esters, polysaccharide sulfates sulfate esters of polysaccharides, synthesized by the action of sulfokinases. There are two possible mechanisms of biosynthesis 1. Sulfation of the polysaccharide chain by phosphoadenosinc phosphostil-fate (PAPS) 2. Polymer formation from sulfated sugar nucleotides. 

Sulfate esters R-O-S-O- II o o Phenol sulfates polysaccharide sulfates... 

Native polysaccharides with acid groups other than the uronic type are not very common except for the sulfate esters. Total acidity may be estimated by direct titration, but erroneous results are obtained if the polysaccharide is alkali-labile as is the case with many oxidized polysaccharides. Addition of calcium acetate (7, 8) or sodium bromide 8, 9) to the polysaccharide solution increases the accuracy of the titration. Other methods for the estimation of carboxyl and other acidic groups involve determination of the amount of methylene blue absorbed, or determination of the amount of silver salt formed by exchange from a solution which contains silver in combination with a very weak acid. The sulfate content of polysaccharide sulfates, such as agar, is obtained by ordinary sulfate analysis of the completely hydrolyzed or ashed polysaccharide. 

Hyaluronic acid is generally prepared from umbilical cords. Most of the protein is removed by digestion with pepsin and trypsin, and the residual protein is separated by the chloroform - amyl alcohol procedure. Hyaluronic acid may be precipitated by fractionation with ammonium sulfate in the presence of pyridine (32). This step also removes a contaminating polysaccharide sulfate. 

Hirabayashi K, Iwata S, Ito M, Shigeta S, Narui T, Mori T, Shibata S (1989) Inhibitory effect of a lichen polysaccharide sulfate, GE-3-S, on the replication of human immunodeficiency virus (HIV) in vitro. Chem Pharm BuU 37 2410-2412... 

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