ausblenden:
Schlagwörter:
Evaporative light scattering (ELS)
Free carbohydrate (FC)
Liquid
chromatography (LC)
Mass spectrometry (MS)
Non-structural carbohydrate
(NSC)
Plant sample
Polysaccharide
Pulsed amperometry (PA)
Refractive
index (RI)
Sample preparation
anion-exchange chromatography
pulsed amperometric detection
ionization
mass-spectrometry
light-scattering detection
scots pine-seedlings
allium-cepa l
sugar phosphates
carbon
extraction
tissues
Zusammenfassung:
This article summarizes the current methods of determination of non-structural carbohydrates (NSCs) in plant samples based on liquid chromatography (LC). NSCs comprise several types of carbohydrates: sugar alcohols (e.g., sorbitol), monosaccharides (e.g., glucose and fructose), disaccharides (e.g., sucrose), oligosaccharides (e.g., raffinose) and polysaccharides [e.g., starch and polyfructans (e.g., inulin)]. NSCs are important in plant metabolism and have to be strictly distinguished from all sorts of structural carbohydrates (e.g., polysaccharide cellulose) that make up the backbone of the plants. Consequently, preservation of structural carbohydrates is a crucial step during sample preparation for NSC determination and is therefore addressed. Sugar alcohols, monosaccharides, disaccharides and those oligosaccharides that are easily soluble in polar solvents can be analyzed directly by high-performance LC. They are also referred to as free carbohydrates (FCs). However, polysaccharides are generally submitted to hydrolyzation into monomers prior to their quantitative analysis. This can be done either chemically, using acids, or enzymatically - both methods are discussed. For identification and quantification of the NSCs after LC separation, the following detectors are used: pulsed amperometry, refractive index, evaporate light scattering and finally, mass spectrometry. (C) 2011 Elsevier Ltd. All rights reserved.
