title: Rapid identification of new minor chemical constituents from Smilacis Glabrae Rhizoma by combined use of UHPLC-Q-TOF-MS, preparative HPLC and UHPLC-SPE-NMR-MS techniques.
abstract: BACKGROUND
  Herbs are an important resource for new drug development. However, the conventional approach for the discovery of new compounds from herbs was time-consuming, tedious, and inefficient.
  
  
  OBJECTIVE
  Establish a quick approach to identify new minor constituents in herbs.
  
  
  METHODS
  The constituents in herbs were firstly analysed using ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). Based on the accurate masses, isotopic ions, and the characteristic fragmentation ions in the mass spectra, the molecular compositions and possible structures of compounds were first deduced. After being enriched by a preparative HPLC method, the potential new minor structures were definitely identified by an on-line UHPLC-solid phase extraction-nuclear magnetic resonance-mass spectrometry (UHPLC-SPE-NMR-MS) approach.
  
  
  RESULTS
  By combined the use of UHPLC-Q-TOF-MS, preparative HPLC and UHPLC-SPE-NMR, three new minor compounds were definitely identified as bis-3,4-dihydroxyphenylpropanoid-substituted catechins (A2 and A3) and 4″-formyl-astilbin (B5). In addition, five isomers of bis-dihydroxyphenylpropanoid-substituted catechin (A1, A4-A7), four isomers of 4″-formyl-astilbin (B1-B4), engeletin formates and isomers (C1-C5), formyl-cinchonains (D1-D4), formyl-caffeoylshikimic acid (E1-E4) were also tentatively determined by MS and MS/MS characterisation.
  
  
  CONCLUSIONS
  The combination of UHPLC-Q-TOF-MS, preparative HPLC and UHPLC-SPE-NMR-MS techniques is a quick and effective approach for finding new minor constitutes from herbs.
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.|Faculty of Chinese Medicines, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
authors.forename: Wan-Yi
authors.initials: WY
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
authors.forename: Elaine Lai-Han
authors.initials: EL
authors.lastname: Leung
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
authors.forename: Liang
authors.initials: L
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau.
authors.forename: Jian-Lin
authors.initials: JL
authors.lastname: Wu
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D055808:Drug Discovery / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D010946:Plants, Medicinal / Q000737:chemistry*
chemical_list: D004365:Drugs, Chinese Herbal; C528109:Rhizoma Smilacinus compound
keywords: Bis-phenylpropanoid-substituted catechin (phenylpropanoid-substituted cinchonains); LC-SPE-NMR-MS; Smilacis Glabrae Rhizoma; UHPLC-Q-TOF-MS; formyl-asitilbin; formyl-caffeoylshikimic acid; formyl-cinchonain; formyl-engeletin