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Direct characterization of bitter acids in a crude hop extract by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry

  • Xiaozhe Zhang
  • Xinmiao LiangEmail author
  • Hongbin Xiao
  • Qing Xu
Articles

Abstract

The applicability of on-line coupling of reversed-phase high-performance liquid chromatography to atmospheric pressure ionization tandem mass spectrometry for the separation and characterization of hop acids mixture from the crude extract of Humulus lupulus was investigated. The solvent system consisting of acetonitrile-aqueous formic acid was used to give proper separation of the six main hop bitter acids within 30 min. Further structural information about the components was acquired by collision-induced dissociation (CID). On the basis of analyses of the fragmentation patterns of the major α- and β-bitter acids respectively, identification of the minor ones was performed using selected reaction monitoring (SRM) with a group of qualitatively relevant selected precursor-product ion transitions for each bitter acid in a single high performance liquid chromatography (HPLC) run. Using this technique, six minor hop acids, including “adprelupulone” observed for the first time in natural resources, were detected along with the six major acids. This hyphenated techniques provides potency for rapid qualitative determination of analogs and homologs in mixtures.

Keywords

High Performance Liquid Chromatography Select Reaction Monitor Bitter Acid Pressure Chemical Ionization Mass Spectrometry Centrifugal Partition Chromatography 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© American Society for Mass Spectrometry 2004

Authors and Affiliations

  • Xiaozhe Zhang
    • 1
  • Xinmiao Liang
    • 1
    Email author
  • Hongbin Xiao
    • 1
  • Qing Xu
    • 1
  1. 1.Group of Pharmaceutical Chemistry, Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina

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