title: LC-UV assay method and UPLC/Q-TOF-MS characterisation of saponins from Ilex paraguariensis A. St. Hil. (mate) unripe fruits.
abstract: BACKGROUND
  Ilex paraguariensis A. St. Hil. (mate) is known in several South American countries because of the use of its leaves in stimulant herbal beverages. High saponin contents were reported in mate leaves and unripe fruits that possess a dissimilar composition. Two LC-UV methods previously reported for mate saponins assay focused on mate leaves and the quantification of the less polar saponin fraction in mate fruits.
  
  
  OBJECTIVE
  To develop and validate a LC-UV method to assay the total content of saponins in unripe mate fruits and characterise the chemical structure of triterpenic saponins by UPLC/Q-TOF-MS.
  
  
  METHODS
  From unripe fruits of mate a crude ethanolic extract was prepared (EX40) and the mate saponin fraction (MSF) purified by solid phase extraction. The LC-UV method was validated using ilexoside II as external standard. UPLC/Q-TOF-MS was adjusted from the LC-UV method to obtain the fragmentation patterns of the main saponins present in unripe fruits.
  
  
  RESULTS
  Both LC-UV and UPLC/Q-TOF-MS methods indicate a wide range of Ilex saponins polarity. The ilexoside II and total saponin content of EX40 were 8.20% (w/w) and 47.60% (w/w), respectively. The total saponin content in unripe fruits was 7.28% (w/w). The saponins present in MSF characterised by UPLC/Q-TOF-MS are derived mainly from ursolic/oleanolic, acetyl ursolic or pomolic acid.
  
  
  CONCLUSIONS
  The validated LC-UV method was shown to be linear, precise, accurate and to cover several saponins previously isolated from Ilex species and could be applied for the quality control of unripe fruit saponins.
authors: Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil.
authors: Maria Paula Garofo
authors: MP
authors: Peixoto
authors: Samuel
authors: S
authors: Kaiser
authors: Simone Gasparin
authors: SG
authors: Verza
authors: Pedro Ernesto
authors: PE
authors: de Resende
authors: Janine
authors: J
authors: Treter
authors: Cabral
authors: C
authors: Pavei
authors: Gustavo Luís
authors: GL
authors: Borré
authors: George González
authors: GG
authors: Ortega
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D000431:Ethanol / Q000737:chemistry; D005638:Fruit / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry; D030019:Ilex paraguariensis / Q000737:chemistry*; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000379:methods*; D015394:Molecular Structure; D009828:Oleanolic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results; D012503:Saponins / Q000032:analysis / Q000737:chemistry*; D052616:Solid Phase Extraction; D014315:Triterpenes / Q000737:chemistry; D014466:Ultraviolet Rays; D000097245:Ursolic Acid
chemical_list: D000431:Ethanol; D006027:Glycosides; D009828:Oleanolic Acid; D010936:Plant Extracts; D012503:Saponins; D014315:Triterpenes; D000097245:Ursolic Acid; C554779:ilexside II; C115535:pomolic acid