title: Simultaneous identification of multiple celangulins from the root bark of Celastrus angulatus using high-performance liquid chromatography-diode array detector-electrospray ionisation-tandem mass spectrometry.
abstract: BACKGROUND
  Celangulins are a small family of β-dihydroagarofuran sesquiterpenoids endowed with diverse polyoxygenated polyol esters and various biological properties. Since our research focuses on celangulins, the development of rapid and sensitive online analytical methods to analyse and characterise them is of great significance.
  
  
  OBJECTIVE
  To develop an HPLC-DAD-ESI-MS/MS method capable of simple and rapid analysis of celangulins in crude extract of root bark of C. angulatus extracts.
  
  
  METHODS
  High-performance liquid chromatography coupled with a diode array detector and electrospray ionisation tandem mass spectrometry was established for the efficient and rapid identification of the celangulins. Chromatographic separations of celangulins were performed on a Hypersil Gold C(18) reverse-phase column by gradient elution with acetonitrile-water as mobile phase at a flow-rate 0.2 mL/min.
  
  
  RESULTS
  ESI/MS/MS analysis of sodium adduct ion ([M + Na](+) ) of each celangulin shows that all the celangulins produced very similar fragmentation profiles, and that the characteristic fragments at m/z 245, m/z 229 and m/z 231 were defined as the diagnostic ions for celangulins. Simultaneously, 46 components in the extracts of this plant were separated, and 36 of them were characterised as celangulins by online ESI/MS/MS and by comparing their retention times, UV and MS spectra with those of authentic compounds.
  
  
  CONCLUSIONS
  HPLC-DAD-ESI-MS/MS was demonstrated to be a powerful tool for the characterisation of minor celangulins in complex samples.
authors.affiliation: Institute of Pesticide Science, Northwest A&F University, Yangling, Shaanxi, 712100, People's Republic of China.
authors.forename: Shaopeng
authors.initials: S
authors.lastname: Wei
authors.forename: Jinming
authors.initials: J
authors.lastname: Gao
authors.forename: Wenjun
authors.initials: W
authors.lastname: Wu
authors.forename: Zhiqin
authors.initials: Z
authors.lastname: Ji
authors.forename: Jiwen
authors.initials: J
authors.lastname: Zhang
mesh_terms: D031247:Celastrus / Q000737:chemistry*; D002681:China; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D012717:Sesquiterpenes / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D004365:Drugs, Chinese Herbal; D012717:Sesquiterpenes; C079978:dihydroagarofuran