Fast and automated characterization of major constituents in rat biofluid after oral administration of Abelmoschus manihot extract using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry and MetaboLynx.

In drug metabolism research, the setting up of a complex series of mass spectrometry experiments and the subsequent analysis of the large amounts of data produced are often time-consuming. In this paper, we describe a strategy using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/QTOFMS) with automated data analysis software (MetaboLynx) for fast analysis of the metabolic profile of flavonoids in Abelmoschus manihot. Rat plasma and urine samples collected 1 h and 0-12 h after oral administration of Abelmoschus manihot were analyzed by UPLC/QTOFMS within 15 min. The post-acquisition data were processed using MetaboLynx. With key parameters carefully set, MetaboLynx is able to show the presence of a wide range of metabolites with only a limited requirement for manual intervention and data interpretation time. A total of 16 and 38 metabolites were identified in plasma and urine compared with blank samples. The results indicated that methylation and glucuronidation after deglycosylation were the major metabolic pathways of flavonoid glycosides in Abelmoschus manihot. The present study provided important information about the metabolism of flavonoid glycosides in Abelmoschus manihot which will be helpful for fully understanding the mechanism of action of this herb. Furthermore, this work demonstrated the potential of the UPLC/QTOFMS approach using MetaboLynx for fast and automated identification of metabolites from Chinese herbal medicines. Copyright (c) 2010 John Wiley & Sons, Ltd.