Carbohydrates polysaccharide

The ranking of carbohydrates/polysaccharides according to mass percentages of subclasses reads ... 

Although carbohydrates/polysaccharides exist in such huge amounts, their industrial processing is expensive due to enormous quality fluctuations of succeeding raw material batches. The reason for these fluctuations is a high variability on the molecular level, particularly in the degree of polymerization distribution, in branching characteristics, and in complex interactive properties. 

From the organochemical point of view, carbohydrates/polysaccharides are more or less substituted polyhydroxy aldehydes (e.g., glucose—>glucans) or polyhydroxy ketons (e.g., fructose-n fructans). From the physicochemical point of view, an enormous heterogeneity also exists in... 

Characteristics due to chemical functionalities (e.g., carboxyl groups) of sample components that control solubility of the sample in aqueous media, viscosity of carbohydrate/polysaccharide solutions, and stability of obtained solutions. 

Carbohydrates (polysaccharides) — starches, cellulose of cotton and wood. 

Complex Carbohydrate polysaccharides such as cellulose and starch Compound a substance consisting of atoms of two or more different elements chemically bonded... 

Finally, this section would remain incomplete without a few comments on the applications of HPLC to a particular group of carbohydrates—polysaccharides—whose determination, both qualitatively and quantitatively, has received much less attention than the rest (56). This may be surprising when the importance of these compounds, in terms of both functional properties and nutrition, is considered, but it is not so surprising when the difficulty of the analyses required is studied. High-performance LC can be used in this field, either to characterize the polysaccharides per se or to study their carbohydrate composition and the nature of bonding after acid or enzymic hydrolysis. 

Carbohydrates in algae and plants are often classified based on methodological discrimination. The structural carbohydrates are not water-soluble, whereas the other types of carbohydrates are water-soluble and typically extracted by hot water. In Phaeocystis five different pools of carbohydrates can be distinguished. Like all algal and plant cells, both solitary and colonial cells produce (1) structural carbohydrates, polysaccharides that are mainly part of the cell wall, (2) mono- and oligosaccharides, which are present as intermediates in the synthesis and catabolism of cell components, and (3) intracellular storage glucan. Colonial cells of Phaeocystis excrete (4) mucopolysaccharides, heteropolysaccharides that... 

Glycodrug Carbohydrate Polysaccharides Glycoprotein Biopharmaceutical Therapeutic antibody Lysosomal disease Lectin Vaccine... 

Many C NMR spectra have been published for humin in peat (Hatcher et al., 1980c, 1983a Preston and Ripmeester, 1982 Dereppeetal., 1983) and all appear to contain peaks for carbohydrates and aromatic, carboxyl, and paraffinic carbons, the proportions of which vary considerably. Hatcher et al. (1983a) pointed out that, while the presence of carbohydrates (polysaccharides) and hgnin was expected, the discovery of significant quantities of paraffinic carbons by C NMR has made a major contribution to our knowledge of the components of peat humin. 

This process of linking (polymerization) can be repeated indefinitely, to build up chains of sugar units. Such chains, which may be several hundreds of units long, are carbohydrates (polysaccharides), the first of the giant molecules we shall shortly discuss. 

Some of the most usefiil materials for the chromatography of labile natural products are the fairly inert polymers of carbohydrates. Polysaccharides can be crosslinked to produce three-dimensional networks (see Fig. 7). These polymeric materials can then be formed into beads. 

The effects of water on the destruction of the protective food structure in some specific dehydrated foods is probably involved in prevention of lipid oxidation in heated meat systems (Karel, 1986). In systems in which there are both surface lipids and lipids encapsulated within a carbohydrate, polysaccharide, or protein matrix, the surface lipids oxidize readily when exposed to air. The encapsulated lipids, however, do not oxidize until the structure of the encapsulated matrix is modified and/or destroyed by adsorption of water as shown by Simatos and Karel (1988). In some IM meats, muscle may be considered as being encased in or surrounded by a humectant matrix. However, free lipid may be left on the surfaces. The unwarranted overuse of lipids, which often happens in the indirect drying process to improve heat transfer and to prevent burning, is detrimental to the products. Prevention of this structural change is of considerable... 

A variety of spectroscopic techniques have been applied to DOC isolated from seawater by cross-flow ultrafiltration or adsorption onto XAD resins. The two techniques isolate very different organic fractions from seawater. Hydrophobic fractions (such as marine humic material) are isolated on XAD resins [48], whereas the organic matter extracted by ultrafiltration is retained primarily on the basis of its molecular size and shape [49], resulting in isolates rich in nitrogen and carbohydrates (polysaccharides). Nuclear magnetic resonance (NMR) spectroscopy has proven successful in distinguishing between the specific structures of XAD-bound humics and the carbohydrates concentrated into colloidal size fractions. 

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