Molecular Diversity

, Volume 15, Issue 2, pp 361–372 | Cite as

HPLC-based activity profiling for GABAA receptor modulators from the traditional Chinese herbal drug Kushen (Sophora flavescens root)

  • Xinzhou Yang
  • Igor Baburin
  • Inken Plitzko
  • Steffen Hering
  • Matthias HamburgerEmail author
Full-Length Paper


An EtOAc extract from the roots of Sophora flavescens (Kushen) potentiated γ-aminobutyric acid (GABA)-induced chloride influx in Xenopus oocytes transiently expressing GABAA receptors with subunit composition, α 1 β 2 γ 2S. HPLC-based activity profiling of the extract led to the identification of 8-lavandulyl flavonoids, kushenol I, sophoraflavanone G, (−)-kurarinone, and kuraridine as GABAA receptor modulators. In addition, a series of inactive structurally related flavonoids were characterized. Among these, kushenol Y (4) was identified as a new natural product. The 8-lavandulyl flavonoids are first representatives of a novel scaffold for the target.


GABAA receptor modulators HPLC-based activity profiling 8-Lavandulyl flavonoids Sophora flavescens Fabaceae 



Time of flight mass spectrometry


Photodiode array


Heteronuclear multiple-bond correlation


Heteronuclear single quantum coherence


Circular dichroism


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Xinzhou Yang
    • 1
  • Igor Baburin
    • 2
  • Inken Plitzko
    • 1
  • Steffen Hering
    • 2
  • Matthias Hamburger
    • 1
    Email author
  1. 1.Institute of Pharmaceutical BiologyUniversity of BaselBaselSwitzerland
  2. 2.Institute of Pharmacology and ToxicologyUniversity of ViennaViennaAustria

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