title: C-glucosidic ellagitannins from Lythri herba (European Pharmacopoeia): chromatographic profile and structure determination.
abstract: BACKGROUND
  Lythri herba, a pharmacopoeial plant material (European Pharmacopoea), is obtained from flowering parts of purple loosestrife (Lythrum salicaria L.). Although extracts from this plant material have been proven to possess some interesting biological activities and its pharmacopoeial standardisation is based on total tannin content determination, the phytochemical characterisation of this main group of compounds has not yet been fully conducted.
  
  
  OBJECTIVE
  To isolate ellagitannins from Lythri herba, determine their structures and develop chromatographic methods for their qualitative analysis.
  
  
  RESULTS
  Five C-glucosidic ellagitannins - monomeric- vescalagin and castalagin together with new dimeric structures - salicarinins A-C, composed of vescalagin and stachyurin, vescalagin and casuarinin, castalagin and casuarinin units connected via formation of valoneoyl group, were isolated using column chromatography and preparative HPLC. Structures were determined according to (1) H and (13) C-NMR (one- and two-dimensional), electrospray ionisation-time of flight (ESI-TOF), electrospray ionisation-ion trap (ESI-MS(n) ) and circular dichroism (CD) spectra, together with acidic hydrolysis products analysis. HPTLC on RP-18 modified plates and HPLC-DAD-MS(n) on RP-18 column methods were developed for separation of the five main ellagitannins.
authors.affiliation: Department of Pharmacognosy and Molecular Basis of Phytotherapy, Medical University of Warsaw, Faculty of Pharmacy, Banacha St. 1, 02-097, Warsaw. jakub.piwowarski@wum.edu.pl
authors.forename: Jakub P
authors.initials: JP
authors.lastname: Piwowarski
authors.forename: Anna K
authors.initials: AK
authors.lastname: Kiss
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002855:Chromatography, Thin Layer / Q000379:methods; D002942:Circular Dichroism; D047348:Hydrolyzable Tannins / Q000032:analysis* / Q000737:chemistry* / Q000302:isolation & purification; D031561:Lythrum / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D047348:Hydrolyzable Tannins; C472513:casuarinin; C111726:salicairine; C084709:vescalagin