Of acidic polysaccharides

Separations of polysaccharides by fractionation on a preparative scale were also examined. Stemming from earlier work in his laboratory on the isolation of acidic polysaccharides by precipitation as their insoluble Cetavlon salts, Stacey and coworkers showed that it was possible to fractionate neutral polysaccharides by selective precipitation with Cetavlon after the formation of borate complexes. 

Shin, J.Y. et al., Immunostimulating effects of acidic polysaccharides extract of Panax ginseng on macrophage function, Immunopharmacol Immunotoxicol, 24, 469, 2002. 

S. Xu and M. Yonese, in Charge Densities and Nanoparticle Formation of Complexes Composed of Acid Polysaccharides and Protein, Nagoya, Japan, 1998, p. E1076. 

The occurrence in many polyglycosiduronic acids of relatively resistant linkages, usually those between uronic acid residues and adjacent residues, has resulted in the isolation of several aldobiouronic acids on graded hydrolysis of acidic polysaccharides. The isolation of such aldobiouronic acids, and subsequent conversion to their fully methylated derivatives, has become a standard procedure in structural studies on polyglycosiduronic acids, especially those of plant gums and mucilages.1 In other cases, partially methylated aldobiouronic acids have been isolated from the hydrolyzates of methylated polysaccharides. The sources and methods of isolation of the methyl ethers of aldobiouronic acids so far examined are given in Table I. Some properties of derivatives are recorded in Table Y. 

Quigley, M.S., Santschi, P.H., Hung, C.C., Guo, L., and Honeyman, B.D. (2002) Importance of acid polysaccharides for 234Th complexation to marine organic matter. Limnol. Oceanogr. 47, 367-377. 

Berth, G., Anger, H., Plashchina, I. G., Braudo, E. E., and Tolstoguzov, V. B. (1982). Structural study of the solutions of acidic polysaccharides. II. Study of some thermodynamic properties of the dilute pectin solutions with different degrees of esterification. Carbohydr. Polym. 2 1-8. 

Sjostrom, E., and Enstrom, B. (1967). Characterization of acidic polysaccharides isolated from different pulps. Tappi 50, 32-36. 

Scott, J. E., Aliphatic Ammonium Salts in the Assay of Acidic Polysaccharides... 

Ammonium Sedts, Aliphatic, in the Asst of Acidic Polysaccharides from Tissues... 

Roberts, R.M., Deshusses, J., and Loewus, F., 1968, Inositol metabolism in plants. V Conversion of myo-inositol to uronic acid and pentose units of acidic polysaccharides in root tips of Zea mays. Plant Physiol. 43 979-989. 

Calcified scales formed inside the Golgi and then extruded have so far only been found in coccolithophorids. In other forms, the matrix is formed in the Golgi but calcification takes place in the cytoplasm. In some cases, the plates of coccolithophorids calcify inside the T-shaped cisternae where the stem is associated with the Golgi stack while the scale is already forming with its future distal surface facing the stack. The scales of coccolithophorids always consist of two layers of a cellulose network of microfibrils radially and concentrically arranged. The outer layer of the scale is made up of acidic polysaccharides and small amounts of protein, probably containing hydroxy-... 

This short discussion illustrates that there is still much to be leamt about the complexing behavior of acidic polysaccharides. 

We chose the acidic polymer as the interior member of the capsule forming pair due to the expected compatibility with cells of acidic polysaccharides such as alginate and carboxymethyl cellulose. For this reason, droplet viscosity and, therefore, stability was improved by synthesizing the acidic polymers as higher molecular weight analogues of the corresponding polybases. 

Hydrolysis. Due to the stability of the glycosyluronic acid linkage to acid hydrolysis, it is difficult to achieve quantitative hydrolysis of acidic polysaccharides (Roden et al., 1972). Conrad et al. (1966) demonstrated that the linkage (Glc/iA-(l- 3)-Fuc/i was 30 times more stable to acid hydrolysis than the linkage (3-D-Glc -( l- 4)-Glc/>. Incomplete hydrolysis and the apparent loss of xylose has been observed with acidic xylans and arabinoxylans, which has been attributed to the accumulation of 2-0-(4-... 

Hydrolysis of acidic polysaccharides with 0.5 M H2SO4 for 4 h at 100°C is generally sufficient to hydrolyze most neutral sugar linkages while leaving aldobiouronic acids intact (Conrad et al., 1966). With this procedure in combination with ion-exchange chromatography the aldobiouronic acids from Phaseolus coccineus pectin (O Neill and... 

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