title: Determination of macrocyclic ellagitannin oenothein B in plant materials by HPLC-DAD-MS: method development and validation.
abstract: BACKGROUND
  Oenothein B (OeB) is a dimeric macrocyclic ellagitannin occurring mainly in the genus Oenothera. In the literature no validated HPLC method for quantification of this compound has been reported.
  
  
  OBJECTIVE
  To develop and validate an efficient HPLC method for quantification of OeB in plant materials.
  
  
  METHODS
  Extraction conditions of OeB from plant material were optimised. Then the first validated HPLC method for quantification was developed.
  
  
  RESULTS
  We have shown that ultrasonic-assisted extraction at 40 °C in 15 min using water are the most optimal conditions for OeB extraction. We have quantified OeB in several plant materials belonging to Oenotheraceae family. The lowest amount of OeB was present in Circaea lutetiana herb (27.64 ± 0.26 mg/g) and the highest was quantified in Epilobium hirsutum aerial parts (72.91 ± 1.38 mg/g).
  
  
  CONCLUSIONS
  The first HPLC method for quantification of OeB in plant materials was developed and validated. We also for the first time optimised the extraction conditions for OeB.
authors.affiliation: Department of Pharmacognosy and Molecular Basis of Phytotherapy, Faculty of Pharmacy, Medical University of Warsaw, Poland. sgranica@wum.edu.pl
authors.forename: Sebastian
authors.initials: S
authors.lastname: Granica
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Bazylko
authors.forename: Anna K
authors.initials: AK
authors.lastname: Kiss
mesh_terms: D005591:Chemical Fractionation / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D031666:Epilobium / Q000737:chemistry; D047348:Hydrolyzable Tannins / Q000032:analysis*; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000379:methods*; D029594:Onagraceae / Q000737:chemistry; D035261:Plant Components, Aerial / Q000737:chemistry; D014465:Ultrasonics
chemical_list: D047348:Hydrolyzable Tannins; C013515:ellagitannin; C080077:oenothein B