Molecular weight carbohydrates and

Glc analysis is limited to lower molecular weight carbohydrates, and does not usually exceed the level of tri- or tetrasaccharides. 

Hydrogen-bonding patterns in crystal structures of the cydodextrins and the simpler carbohydrates differ. The infinite, homodromic chains are common both in the low molecular-weight carbohydrates and in the cydodextrins. The principal difference lies in the frequency of occurrence of the homodromic and antidromic cycles, which are common in the cyclodextrin crystal structures and rare in the mono-, di-, and trisaccharides. The cyclic patterns are the rule in the clathrate hydrates and in the ices. From this point of view, the hydrogen-bonding patterns of the hydrated cydodextrins lie between those of the simpler hydrated carbohydrates and those of the hydrate inclusion compounds, discussed in Part IV, Chapter 21. 

Low molecular weight carbohydrates and cannot be hydrolysed further. 

For mixture.s the picture is different. Unless the mixture is to be examined by MS/MS methods, usually it will be necessary to separate it into its individual components. This separation is most often done by gas or liquid chromatography. In the latter, small quantities of emerging mixture components dissolved in elution solvent would be laborious to deal with if each component had to be first isolated by evaporation of solvent before its introduction into the mass spectrometer. In such circumstances, the direct introduction, removal of solvent, and ionization provided by electrospray is a boon and puts LC/MS on a level with GC/MS for mixture analysis. Further, GC is normally concerned with volatile, relatively low-molecular-weight compounds and is of little or no use for the many polar, water soluble, high-molecular-mass substances such as the peptides, proteins, carbohydrates, nucleotides, and similar substances found in biological systems. LC/MS with an electrospray interface is frequently used in biochemical research and medical analysis. 

For the most part, low molecular weight carbohydrates of commerce are made by depolymerization via enzyme- or acid catalyzed hydrolysis of polysaccharides. Only sucrose and, to a very much lesser extent, lactose, both disaccharides, are commercial low molecular weight carbohydrates not made in this way. 

Since polysaccharides are the most abundant of the carbohydrates, it is not surprising that they comprise the greatest part of industrial utiliza tion (9,22). Most of the low molecular weight carbohydrates of commerce are produced by depolymerization of starch. Polysaccharide materials of commerce can be thought of as falling into three classes cellulose, a water-insoluble material starches, which are not water-soluble until cooked and water-soluble gums. 

Herein, we investigated the contents, molecular weight distribution and carbohydrate comptosition of polyuronides and hemicelluloses, and PG activity in the ripening strawberry. 

A5.4.7 Simple sugars, lower-molecular weight oligomers, and carbohydrate polymers... 

Smith and coworkers152 published a relatively complete paper on the thin-layer chromatography, on silica gel, of carbohydrates of low molecular weight. Bancher and coworkers153 reported the thin-layer chromatography of degradation products of carbohydrates, including aldonic acids and aldonolactones. 

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. 

There are many recent examples of xylanase induction in fungi grown on media containing xylan, hemicellulose-rich material and low molecular weight carbohydrates (42-66). It has generally been observed that higher... 

Of the substances studied the most abundant in the Paleozoic rocks of the area are furfurals presumably derived from carbohydrates, higher molecular weight hydrocarbons, and in a few samples, amino acids. Acid and base soluble, low boiling substances having some properties of heterocyclic compounds, phenols, and organic acids exist in smaller amounts. 

Table III. Molecular Weight, Carbohydrate Content, and the Ratio of Avicelase to CMCase Activity...

The present utilization of carbohydrates as a feedstock for the chemical industry is modest, when considering their ready availability, low cost and huge potential [92], The bulk of the annually renewable carbohydrate biomass consists of polysaccharides, but their non-food utilization is still modest. The low-molecular-weight carbohydrates, that is, the constituent units of these polysaccharides, are potential raw materials for several commodity chemicals in fact, glucose (available from cornstarch, bagasse, molasses, wood), fructose (inulin), xylose (hemicelluloses) or the disaccharide sucrose (world production 140 Mtons year-1) are inexpensive and available on a scale of several ten thousands. 

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