Determination monosaccharide composition

If oligosaccharides are not cleaved from the protein by acid hydrolysis but by y0-elimination for determining monosaccharide composition, as is done for... 

The monosaccharide composition of all the samples was determined by GLC analysis of the trimethylsilyl methyl glycoside derivatives [1]. 

For monitoring the extent of polysaccharide hydrolysis, l.c. methods that sepeu ate and analyze the non-fermentable oligosaccharides (d.p. 3-30) derived from cellulose, hemicellulose, and pectins are useful, and have already been described (see Section III,l,c). For determination of the monosaccharide composition of completely hydrolyzed, plant polysaccharides, l.c. is especially useful and has been applied to the compositional analysis of hydrolyzed plant fiber,wood pulps,plant cell-walls,and cotton fibers.In these representative examples, the major sugars of interest, namely, glucose, xylose, galactose, arabinose, and mannose, have traditionally been difficult to resolve by l.c. The separa-... 

Structural studies of glycosphingolipids involves determination of the structure of the oligosaccharide chain and of the lipid moiety. For the oligosaccharide chain, it is necessary to determine the composition, molar ratio, and sequence of the monosaccharides, their pyranose or furanose nature, and the position of glycosidic bonds and their configuration for the lipid moiety, the composition of the fatty acids and sphingosine bases must be determined. Used for these purposes are the classical, chemical methods, conventionally accepted in the chemistry of carbohydrates and lipids and based on the degradation of compounds, enzymic, and physicochemical methods, primarily mass spectrometry and n.m.r. spectroscopy. 

Determination of the monosaccharide composition by gas chromatography of alditol acetates is commonly used for cell wall analyses because the procedure gives a single peak for each sugar. An alternative is to prepare trimethylsilyl (TMS) derivatives. However, these are easily hydrolyzed by moisture in the atmosphere and therefore should be analyzed in the gas chromatograph immediately, whereas alditol acetates are relatively more stable and could be rerun on the gas chromatograph the following day if required. 

In this procedure, the cell walls are first treated with TFA to determine the neutral monosaccharide composition of the noncellulosic polysaccharides. The TFA-insoluble residue is then hydrolyzed using a two-stage sulfuric acid procedure to determine cellulose content. 

Harris, P.J., Blakeney, A.B., Henry, R.J., and Stone, B.A. 1988. Gas chromatographic determination of the monosaccharide composition of plant cell wall preparations. J. Assoc. Off. Anal. Chem. 71 272-275. 

Integrated, 13C-n.m.r. spectra have been used extensively to study mutarotational equilibria of monosaccharides, especially of ketoses, which do not have well-resolved, H-n.m.r. spectra,26-33 and also have been used to determine the composition of crude reaction-mixtures.34... 

Today (2000), GC/MS is still the method of choice for the determination of the monosaccharide composition of oligosaccharides and is widely used. The analysis starts with the hydrolysis or alcoholysis of the oligosaccharide to monosaccharides, which after derivatization (mostly by trimethylsilylation) are analysed by GC/MS. [221] Monosaccharide identification is based on comparison of retention time and fragmentation pattern with references. 

From a study of 2,3-anhydro derivative of cellulose by infrared spectroscopy combined with the determination of the monosaccharide composition of the products of its acetylation and interaction with sodium methylate, we conclude that the mixed polysacdiaride synthesized contains glucose and 2,3-anhydromannose units. 

In addition to determining the monosaccharide composition, linkage types, and sequence of residues in a cell wall polysaccharide, it is also essential to determine the anomeric configuration of the glycosyl residues. As with determining the sequence of glycosyl residues, the method of choice, be it chemical, enzymic, or physical, are dependent on the type of material under investigation and the amount available. 

Despite the development of ESI and MALDI modes of ionization, GC/MS is still a popular method for determination of the monosaccharide composition of carbohydrate chains [13]. This method involves breaking the oligosaccharide into constituent monosaccharides by hydrolysis or methanolysis. Following derivatization, the released monosaccharides are analyzed by GC/MS to identify sugar residues through their retention times and mass spectral profile. Common derivatization procedures are methylation, acetylation, and trimethylsilylation. 

Following acid hydrolysis the monosaccharide composition of the carbohydrate fraction was determined by HPLC or by thin-layer chromatography. 

Zanetta J-P, Timmerman P, and Leroy Y (1999a) Gas-liquid chromatography of heptafluorobutyrate derivatives of the O-methyl glycosides on capillary columns a method for the quantitative determination of the monosaccharide composition of glycoproteins and glycoli-pids. Glycobiology 9 255-266. 

F.a.b.m.s. on multisulfated oligosaccharides from human respiratory mucous glycoprotein, combined with monosaccharide composition, allowed for determination of carbohydrate sequence, and die number and position of sulfate esters. ... 

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