INTRODUCTION: Triterpene saponins are the major bioactive components in the root of Pulsatilla chinensis (Bunge) Regel (RPC), and have been reported to possess antitumor and immunological adjuvant activities. However, the isolation, purification and elucidation procedures of triterpene saponins from RPC are difficult and time consuming due to high polarity and structural similarity. OBJECTIVES: To develop an analytical strategy for discovering and elucidating triterpene saponins in RPC. METHODS: Methanolic extract of RPC is analysed by high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight-mass spectrometry (HPLC-ESI-QTOF-MS/MS). The MS and MS/MS experiments are conducted using the negative-ionisation mode, in order to provide molecular-mass information and production spectra for the structural elucidation of compounds. RESULTS: Based on retention times, accurate mass and mass spectrometric fragmentation, 24 triterpene saponins are identified or tentatively elucidated from RPC, of which nine triterpene saponins were not reported previously. CONCLUSION: The HPLC-ESI-QTOF-MS/MS could be employed as a rapid, effective technique to screen and identify triterpene saponins in RPC without tedious and time-consuming isolation of pure constituents.
INTRODUCTION:Triterpene saponins are the major bioactive components in the root of Pulsatilla chinensis (Bunge) Regel (RPC), and have been reported to possess antitumor and immunological adjuvant activities. However, the isolation, purification and elucidation procedures of triterpene saponins from RPC are difficult and time consuming due to high polarity and structural similarity. OBJECTIVES: To develop an analytical strategy for discovering and elucidating triterpene saponins in RPC. METHODS:Methanolic extract of RPC is analysed by high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight-mass spectrometry (HPLC-ESI-QTOF-MS/MS). The MS and MS/MS experiments are conducted using the negative-ionisation mode, in order to provide molecular-mass information and production spectra for the structural elucidation of compounds. RESULTS: Based on retention times, accurate mass and mass spectrometric fragmentation, 24 triterpene saponins are identified or tentatively elucidated from RPC, of which nine triterpene saponins were not reported previously. CONCLUSION: The HPLC-ESI-QTOF-MS/MS could be employed as a rapid, effective technique to screen and identify triterpene saponins in RPC without tedious and time-consuming isolation of pure constituents.