Molecular weight polysaccharides and

Prior to xylan removal it is possible to extract from the plant material those hemicelluloses soluble in dilute alkali. Soluble hemicelluloses of this type are the principal impurities extracted with xylan and consist for the most part of low molecular weight polysaccharides and polyuronides. Corn cob holocellulose may be freed of these compounds (called hemicellulose-B fraction, see Figure 2) by extraction with potas-... 

Low molecular weight polysaccharides and oligosaccharides are common synthetic targets [21]. Many of them have found applications as pharmaceuticals [22,23] and nutriceuticals [24,25] (also known as fimctional foods). As specialty chemicals, these materials have been used, for example, as binders, encapsulants, protective colloids, bulking agents, and film formers. 

It is well known the tendency of polysaccharides to associate in aqueous solution. These molecular associations can deeply affect their function in a particular application due to their influence on molecular weight, shape and size, which determines how molecules interact with other molecules and water. There are several factors such as hydrogen bonding, hydrophobic association, an association mediated by ions, electrostatic interactions, which depend on the concentration and the presence of protein components that affect the ability to form supramolecular complexes. 

Richmond, M. D. and Yeung, E. S., Development of a laser-excited indirect fluorescence detection for high-molecular weight polysaccharides in capillary electrophoresis, Anal. Biochem., 210, 245, 1993. 

The power and potential of microorganisms to adapt and prosper in a wide range of environments are well known. They have the ability to break down high molecular weight carbon and energy sources into small molecules, convert these to primary metabolites such as amino acids, nucleotides, vitamins, carbohydrates, and fatty acids, and finally build these basic materials into proteins, coenzymes, nucleic acids, mucopep-tides, polysaccharides and hpids used for growth. 

N-terminal amino acid Amino acid with an amino end group, nucleoside Contains a pentose and base, nucleotide Contains a phosphate, pentose, and base, oligosaccharide Low molecular weight polysaccharide, phenotype The observable, physical characteristics of an organism. 

Wood contains about 40-50% cellulose with the remaining being lignin and lower-molecular-weight polysaccharides. Treatment of wood pulp with acid and steam followed by basic sodium sulfide yields a product that is 92-98% cellulose. 

Yu, L. -P, Rollangs, J. E. (1987). Low-angle laser light scattering-aqueous size exclusion chromatography of polysaccharides molecular weight distribution and polymer branching determination. Journal of Applied Polymer Science, 33, 1909-1921. 

Wagner et al. 33) have shown that two distinct polysaccharide fractions from Echinacea purpurea exhibited pronounced activities characterized by a high rate of phagocytosis stimulation. One polysaccharide was shown to be a heteroxylan of molecular weight 35000 and an arabinorhamnogalactan of molecular weight 450000. The main characteristics of these polysaccharides from Echinacea were the optimal solubility in water, the high content of uronic acids, and the very complex structure. 

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