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Hai-xue Kuang - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of bioactive components and pharmacokinetics of Caulophyllum robustum in rat plasma after oral administration by UPLC-ESI-MS/MS.
    Journal of Asian Natural Products Research, 2019
    Co-Authors: Ji-xin Duan, Hai-xue Kuang, Yuyan Guo, Qiuhong Wang
    Abstract:

    A UPLC–MS/MS method was developed and validated the determination and pharmacokinetic study of magnoflorine, cauloside C, hederagenin, and oleanolic acid from Caulophyllum robustum. Digoxin was use...

  • analysis of bioactive components and pharmacokinetics of Caulophyllum robustum in rat plasma after oral administration by uplc esi ms ms
    Journal of Asian Natural Products Research, 2019
    Co-Authors: Ji-xin Duan, Hai-xue Kuang, Yuyan Guo, Qiuhong Wang
    Abstract:

    A UPLC–MS/MS method was developed and validated the determination and pharmacokinetic study of magnoflorine, cauloside C, hederagenin, and oleanolic acid from Caulophyllum robustum. Digoxin was use...

  • Energy-resolved technique for discovery and identification of malonyl-triterpene saponins in Caulophyllum robustum by UHPLC-electrospray Fourier transform mass spectrometry.
    Journal of Mass Spectrometry, 2016
    Co-Authors: Yong-gang Xia, Jun Liang, Bing-you Yang, Hai-xue Kuang
    Abstract:

    Malonyl-triterpene saponins (MTSs) attract scientific attentions because of their structural diversities and valuable bioactivities. However, its thermal instability brings a huge amount of challenges for isolation and purification of this class of compounds. To our best knowledge, there has been no report on isolation and analysis of MTSs from genus Caulophyllum. In this study, a strategy combining data acquisition using an energy-resolved technique and the narrow widow extracted ion chromatograms as data mining method was developed for discovery and identification of MTSs in Caulophyllum robustum hair roots by ultra high liquid chromatography coupled to electrospray ionization Fourier transform mass spectrometry. The method was performed at an independent MS full scan using our bottom-up energies by in-source collision induced dissociations with 0, 25, 50 and 100 eV in both positive and negative modes. Precursor ion as well as fragment ion information was simultaneously collected from four energy-resolved MS spectra in a single run of 18 min. The fragmentation pathways of intact deprotonated, protonated and sodium ions of MTSs were proposed for the structural elucidation of Caulophyllum MTSs. A flowchart involving a stepwise procedure based on key fragments from ESI- /ESI+ -FT-MS(1, 1) to MS(1, 4) spectra was constructed for the identification of structural elements in the MTSs. As a result, a total of 23 MTSs were discovered and tentatively identified, which had not been reported from Caulophyllum species before. All of these were potentially new compounds. This study provides an excellent example for discovery and identification of MTSs in herb medicines. Copyright © 2016 John Wiley & Sons, Ltd.

  • Analysis of oligosaccharide sequences of trace Caulophyllum robustum saponins by direct infusion multiple-stage tandem mass spectrometry.
    Journal of Pharmaceutical and Biomedical Analysis, 2015
    Co-Authors: Yong-gang Xia, Jun Liang, Bing-you Yang, Hai-xue Kuang
    Abstract:

    Abstract The saponins in Caulophyllum robustum have not yet been fully characterized. Furthermore these saponins are often present in trace amounts and are structurally complex. Here, a simple direct infusion electrospray ion trap multiple-stage tandem mass spectrometry (DI-ESI-IT-MS n ) method was described for the characterization of trace C. robustum saponins. Eight reference saponins from the C. robustum hairy root were investigated by DI-ESI-IT-MS n in positive ion mode. Some fragmentation approaches were proposed through analysis of the [M+Na] + ions: (1) preferential cleavage of the C-28 ester glycosidic bond to provide complementary [Y 0 α +Na] + and [B α +Na] + ions for bidesmosidic saponins; (2) diagnostically neutral loss of CO 2 from free carboxyl groups at C-28 for monodesmosidic saponins; and (3) the ion intensity ratio between [C 2 β +Na] + and [B 2 β +Na] + , which is sensitive to the structural differences between the two isomeric β -sugar chains (Glc→ 2 Ara and Glc→ 3 Ara). The DI-ESI-IT-MS n method was successfully used for the analysis of trace C. robustum saponins with [M+Na] + ions at m / z 1745.6, 1729.5, 1583.7, 1567.7, 1421.7 and 1405.7. This article highlights the discovery and identification of complex α - and β -oligosaccharide moieties in Caulophyllum saponins by glycosidic product ions along with cross ring cleavage product ions. Five oligosaccharide moieties were unambiguously or tentatively identified as Rha→ 4 Glc→ 6 Glc→ 4 Rha→ 4 Glc→ 6 Glc, Glc→ 4 Glc→ 6 Glc→ 4 Rha→ 4 Glc→ 6 Glc, Rha→Glc→Glc (Glc)→ 2,3 Ara, Glc→Glc (Glc) → 2,3 Ara and Glc (Glc)→ 2,3 Ara. Accuracy of the analytical procedure was demonstrated by structural identification of two saponins isolated using 1D and 2D-NMR spectroscopy. The DI-ESI-IT-MS n method facilitates rapid discovery and analysis of trace Caulophyllum saponins and is a powerful and practical tool for structural characterization of complex oligosaccharide moieties in triterpene saponins.

  • A strategy for characterization of triterpene saponins in Caulophyllum robustum hairy roots by liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry.
    Journal of Pharmaceutical and Biomedical Analysis, 2014
    Co-Authors: Yong-gang Xia, Jun Liang, Bing-you Yang, Hai-xue Kuang, Catharine A. Ortori, David A. Barrett
    Abstract:

    Abstract Triterpene saponins are important bioactive constituents widely distributed in many plants. Saponins present in Caulophyllum (Berberidaceae) have not been fully characterized. In this study, we studied triterpene saponins from Caulophyllum robustum using liquid chromatography combined with electrospray ionization quadrupole time-of-flight mass spectrometry (LC-qTOF-MS). Rapid identification of Caulophyllum saponins was facilitated using low and high MS cone voltages to induce controlled fragmentation in positive mode. The full scan spectra at low cone voltage of 40 V provided considerable structural information relating to aglycone skeletons, sugar types, and linked sequences for Caulophyllum saponins. Seven Caulophyllum aglycones were differentiated and identified by their diagnostic fragment ions combined with accurate mass measurements and characteristic fragmentation pathways. Peak intensity ratio of [aglycone+H−2H2O]+ to [aglycone+H−H2O]+ in full scan spectra acquired with low cone voltage is correlated with structural features of hederagenin and echinocystic acid and is useful for the discrimination of these positional isomers. However, at a high voltage of 200 V, the saponin [M+H]+ ion and its fragmentation ions were not present; and the single saponin [M+Na]+ generated [Bα+Na]+ and [Y0α+Na]+ by in-source fragmentation, which provided structural information on the α- and β-sugar chains in the saponins. This approach enabled simultaneous acquisition of structural information on both aglycones and sugar chains from full scan spectra in one injection. Based on the developed strategy, 51 triterpene saponins of seven different classes were fully characterized or tentatively identified, of which 32 constituents were the first to be reported in genus Caulophyllum and 18 compounds were characterized as potentially new compounds.

Qiuhong Wang - One of the best experts on this subject based on the ideXlab platform.

Ji-xin Duan - One of the best experts on this subject based on the ideXlab platform.

Yong-gang Xia - One of the best experts on this subject based on the ideXlab platform.

  • Energy-resolved technique for discovery and identification of malonyl-triterpene saponins in Caulophyllum robustum by UHPLC-electrospray Fourier transform mass spectrometry.
    Journal of Mass Spectrometry, 2016
    Co-Authors: Yong-gang Xia, Jun Liang, Bing-you Yang, Hai-xue Kuang
    Abstract:

    Malonyl-triterpene saponins (MTSs) attract scientific attentions because of their structural diversities and valuable bioactivities. However, its thermal instability brings a huge amount of challenges for isolation and purification of this class of compounds. To our best knowledge, there has been no report on isolation and analysis of MTSs from genus Caulophyllum. In this study, a strategy combining data acquisition using an energy-resolved technique and the narrow widow extracted ion chromatograms as data mining method was developed for discovery and identification of MTSs in Caulophyllum robustum hair roots by ultra high liquid chromatography coupled to electrospray ionization Fourier transform mass spectrometry. The method was performed at an independent MS full scan using our bottom-up energies by in-source collision induced dissociations with 0, 25, 50 and 100 eV in both positive and negative modes. Precursor ion as well as fragment ion information was simultaneously collected from four energy-resolved MS spectra in a single run of 18 min. The fragmentation pathways of intact deprotonated, protonated and sodium ions of MTSs were proposed for the structural elucidation of Caulophyllum MTSs. A flowchart involving a stepwise procedure based on key fragments from ESI- /ESI+ -FT-MS(1, 1) to MS(1, 4) spectra was constructed for the identification of structural elements in the MTSs. As a result, a total of 23 MTSs were discovered and tentatively identified, which had not been reported from Caulophyllum species before. All of these were potentially new compounds. This study provides an excellent example for discovery and identification of MTSs in herb medicines. Copyright © 2016 John Wiley & Sons, Ltd.

  • Analysis of oligosaccharide sequences of trace Caulophyllum robustum saponins by direct infusion multiple-stage tandem mass spectrometry.
    Journal of Pharmaceutical and Biomedical Analysis, 2015
    Co-Authors: Yong-gang Xia, Jun Liang, Bing-you Yang, Hai-xue Kuang
    Abstract:

    Abstract The saponins in Caulophyllum robustum have not yet been fully characterized. Furthermore these saponins are often present in trace amounts and are structurally complex. Here, a simple direct infusion electrospray ion trap multiple-stage tandem mass spectrometry (DI-ESI-IT-MS n ) method was described for the characterization of trace C. robustum saponins. Eight reference saponins from the C. robustum hairy root were investigated by DI-ESI-IT-MS n in positive ion mode. Some fragmentation approaches were proposed through analysis of the [M+Na] + ions: (1) preferential cleavage of the C-28 ester glycosidic bond to provide complementary [Y 0 α +Na] + and [B α +Na] + ions for bidesmosidic saponins; (2) diagnostically neutral loss of CO 2 from free carboxyl groups at C-28 for monodesmosidic saponins; and (3) the ion intensity ratio between [C 2 β +Na] + and [B 2 β +Na] + , which is sensitive to the structural differences between the two isomeric β -sugar chains (Glc→ 2 Ara and Glc→ 3 Ara). The DI-ESI-IT-MS n method was successfully used for the analysis of trace C. robustum saponins with [M+Na] + ions at m / z 1745.6, 1729.5, 1583.7, 1567.7, 1421.7 and 1405.7. This article highlights the discovery and identification of complex α - and β -oligosaccharide moieties in Caulophyllum saponins by glycosidic product ions along with cross ring cleavage product ions. Five oligosaccharide moieties were unambiguously or tentatively identified as Rha→ 4 Glc→ 6 Glc→ 4 Rha→ 4 Glc→ 6 Glc, Glc→ 4 Glc→ 6 Glc→ 4 Rha→ 4 Glc→ 6 Glc, Rha→Glc→Glc (Glc)→ 2,3 Ara, Glc→Glc (Glc) → 2,3 Ara and Glc (Glc)→ 2,3 Ara. Accuracy of the analytical procedure was demonstrated by structural identification of two saponins isolated using 1D and 2D-NMR spectroscopy. The DI-ESI-IT-MS n method facilitates rapid discovery and analysis of trace Caulophyllum saponins and is a powerful and practical tool for structural characterization of complex oligosaccharide moieties in triterpene saponins.

  • A strategy for characterization of triterpene saponins in Caulophyllum robustum hairy roots by liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry.
    Journal of Pharmaceutical and Biomedical Analysis, 2014
    Co-Authors: Yong-gang Xia, Jun Liang, Bing-you Yang, Hai-xue Kuang, Catharine A. Ortori, David A. Barrett
    Abstract:

    Abstract Triterpene saponins are important bioactive constituents widely distributed in many plants. Saponins present in Caulophyllum (Berberidaceae) have not been fully characterized. In this study, we studied triterpene saponins from Caulophyllum robustum using liquid chromatography combined with electrospray ionization quadrupole time-of-flight mass spectrometry (LC-qTOF-MS). Rapid identification of Caulophyllum saponins was facilitated using low and high MS cone voltages to induce controlled fragmentation in positive mode. The full scan spectra at low cone voltage of 40 V provided considerable structural information relating to aglycone skeletons, sugar types, and linked sequences for Caulophyllum saponins. Seven Caulophyllum aglycones were differentiated and identified by their diagnostic fragment ions combined with accurate mass measurements and characteristic fragmentation pathways. Peak intensity ratio of [aglycone+H−2H2O]+ to [aglycone+H−H2O]+ in full scan spectra acquired with low cone voltage is correlated with structural features of hederagenin and echinocystic acid and is useful for the discrimination of these positional isomers. However, at a high voltage of 200 V, the saponin [M+H]+ ion and its fragmentation ions were not present; and the single saponin [M+Na]+ generated [Bα+Na]+ and [Y0α+Na]+ by in-source fragmentation, which provided structural information on the α- and β-sugar chains in the saponins. This approach enabled simultaneous acquisition of structural information on both aglycones and sugar chains from full scan spectra in one injection. Based on the developed strategy, 51 triterpene saponins of seven different classes were fully characterized or tentatively identified, of which 32 constituents were the first to be reported in genus Caulophyllum and 18 compounds were characterized as potentially new compounds.

  • Genus Caulophyllum: An Overview of Chemistry and Bioactivity
    Evidence-based Complementary and Alternative Medicine, 2014
    Co-Authors: Yong-gang Xia, Jun Liang, Bing-you Yang, Hai-xue Kuang
    Abstract:

    Recently, some promising advances have been achieved in understanding the chemistry, pharmacology, and action mechanisms of constituents from genus Caulophyllum. Despite this, there is to date no systematic review of those of genus Caulophyllum. This review covers naturally occurring alkaloids and saponins and those resulting from synthetic novel taspine derivatives. The paper further discussed several aspects of this genus, including pharmacological properties, mechanisms of action, pharmacokinetics, and cell membrane chromatography for activity screening. The aim of this paper is to provide a point of reference for pharmaceutical researchers to develop new drugs from constituents of Caulophyllum plants.

Shigetomo Yonemori - One of the best experts on this subject based on the ideXlab platform.