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Abstract

Glycosphingolipids were prepared from pig lung and pooled into two fractions with (i) < or = 3 sugar residues, and (ii) > or = 3 sugar residues. Oligosaccharides were prepared and used for gas chromatography, gas chromatography/mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry. The glycolipid fractions i and ii were further characterised and purified using a novel method based on high performance liquid chromatography "on-flow" proton nuclear magnetic resonance. The LC "on-flow" NMR technique showed good chromatographic separation and gave NMR spectral information which could be used as guidance for pooling of the separated mixture glycolipids. Conventional 1H NMR, thin layer immunostaining, gas chromatography, gas chromatography/mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry were used to characterise the glycolipids and to validate LC-NMR spectral data.

Carbohydrate Structural Determination by NMR Spectroscopy: Modern Methods and Limitations

“…One approach is to measure normal 1D 1 H or 13 C spectra of mixtures of, e.g., polysaccharides and then with the use of spectra from isolated structures deduce the composition of the mixtures using statistical methods. , For even more complex mixtures such as blood plasma, information about the content of low molecular weight compounds such as monosaccharides can be obtained using high-field NMR. , It is advantageous to suppress the signals from the high molecular weight compounds using methods based on relaxation or diffusion . Finally, chromatography with inline NMR detection has been used for the identification of carbohydrate components in complex mixtures. − …”

“…225 Finally, chromatography with inline NMR detection has been used for the identification of carbohydrate components in complex mixtures. [226][227][228][229] A special application of NMR to complex mixtures of oligosaccharides is the determination of the substrate specificity for carbohydrate hydrolyzing enzymes directly in the NMR tube. This offers detailed information compared to other methods because intermediate products can be identified positively in the mixture.…”

Polyglycosylceramides, Poly-N-acetyllactosamine-Containing Glycosphingolipids: Methods of Analysis, Structure, and Presumable Biological Functions

“…These powerful techniques are now under development in many laboratories, and one can anticipate that they will gradually replace traditional analytical approaches used for analysis of complex mixtures of molecules. New reports constantly appear on various applications of LC-MS, ,, CE-MS, and LC NMR . However, at present, laborious combinations of traditional and modern techniques are still in practical use, including chemical and enzymatic fragmentations, other chemical modifications, traditional methylation analysis, MS and/or NMR of separated molecules or fragments, etc.…”

Isolation and Structural Elucidation of Steroid Oligoglycosides from the StarfishAsteriasrubens by Means of Direct Online LC-NMR-MS Hyphenation and One- and Two-Dimensional NMR Investigations

“…Although LC-NMR [3] has frequently been used for analyses of mixtures of natural products during recent years, [4][5][6][7][8][9][10][11] this technique has not yet been applied to saponins in the molecular weight range of 1200-1400 a.m.u.…”