Determination of regioisomeric distribution in carbohydrate fatty acid monoesters by LC-ESI-MS.
A new LC-ESI-MS method for characterizing the regioisomeric distribution in carbohydrate monoesters with long-chain fatty acids is described. Sucrose monolaurate mixtures were used for development of the method. The surfactant nature and high polarity of these compounds make them appropriate analytes for being detected by electrospray-ionization mass spectrometry (ESI-MS). Despite the structural similarity of regioisomers, an excellent resolution of all regioisomers present in the different samples studied (sucrose monodecanoates, sucrose monolaurates, sucrose monopalmitates and melezitose monolaurates) is achieved. Reversed-phase liquid chromatography with isocratic acetonitrile-water mixtures was used for a proper separation of the analytes. Finally, the superiority of this chromatographic method for determining the regioselectivity in enzymatic carbohydrate acylation reactions, with respect to the typical methodology based on routine 13C NMR spectroscopy, is also discussed.
Pérez-Victoria
Ignacio
I
Departamento de Química, Puleva Biotech, SA, 18004 Granada, Spain.
Zafra
Alberto
A
Morales
Juan Carlos
JC
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005227:Fatty Acids / Q000737:chemistry*; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D002241:Carbohydrates; D005227:Fatty Acids