Analysis of iminosugars and other low molecular weight carbohydrates in Aglaonema sp. extracts by hydrophilic interaction liquid chromatography coupled to mass spectrometry

Abstract

A method by hydrophilic interaction liquid chromatography coupled to tandem mass spectrometry (HILIC-MS2) has been successfully developed for the simultaneous analysis of bioactive iminosugars and other low molecular weight carbohydrates in Aglaonema leaf extracts. Among other experimental chromatographic conditions, mobile phase eluents, additives and column temperature were evaluated in terms of retention time, resolution, peak width and symmetry provided for target carbohydrates. In general, narrow peaks (wh: 0.2–0.6 min) with good symmetry (As: 0.9–1.3) and excellent resolution (Rs > 1.8) were obtained for iminosugars using an acetonitrile:water gradient with 5 mM ammonium acetate in both eluents at 55 °C. Tandem mass spectra were used to confirm the presence of previously detected iminosugars in Aglaonema extracts and to tentatively identify for the first time others such as miglitol isomer, glycosyl–miglitol isomers and glycosyl–DMDP isomers. Concentration of total iminosugars varied from 1.35 to 2.84 mg g−1 in the extracts of the different Aglaonema samples analyzed. To the best of our knowledge, this is the first time that a HILIC-MS2 method has been proposed for the simultaneous analysis of iminosugars and other low molecular weight carbohydrates of Aglaonema sp. extracts.