Systematic Characterisation of Secondary Metabolites from Ixeris sonchifolia by the Combined Use of HPLC-TOFMS and HPLC-ITMS

Introduction - Ixeris sonchifolia (Bunge) Hance, a folk medicine, has been widely used in China for its anti-inflammatory and haemostatic effects. However, the miscellaneous component composition of this herbal medicine is not well known. Objective - To develop a fast and comprehensive analytical method for the characterisation of various components from I. Sonchifolia, as a tool for the quality control of the herb and its related preparations. Methodology - Ixeris sonchifolia samples were extracted with 60% aqueous methanol, purified by solid-phase extraction and then analysed by the combinatorial use of HPLC-TOFMS and HPLC-ITMS. Results - A total of six sesquiterpene lactones, six phenolic acids and seven flavonoids were identified or tentatively characterised. Five of them were reported for the first time in I. sonchifolia and, in particular, two amino acid-sesquiterpene lactone conjugates, 11,13-dihydro-13-prolyl-ixerin Z and 11,13-dihydro-13-prolyl-ixerin Z(1), that were first found in this plant source. Conclusion - A global profile of I. sonchifolia constituents was described, which could be useful for the quality control of this herb and its related preparations. The employed combination of HPLC-TOFMS and HPLC-ITMS could also be a promising tool for the analysis of other herbal medicines containing sesquiterpene lactones, phenolic acids or flavonoids. Copyright (C) 2010 John Wiley & Sons, Ltd.