Extraction and identification of tannins from the stems of Geum urbanum L.

Mette Rams, Mikkel Pyndt Andersen & Helene Nørgaard Bachmann

Studenteropgave: Semesterprojekt

Abstrakt

A common cause of cancer is oxidative damage to cells due to decreased conversion of reactive oxygen species (ROS). Hence compounds with antioxidant activities are of great interest. Hydrolyzable and condensed tannins are known to have antioxidant effects and have been found in several plants. We examined dried stems of Geum urbanum L. and detected tannins using thin layer chromatography (TLC). We separated the tannins using three types of columns; Sephadex LH-20, partition column chromatography with cellulose and Diaion HP-20. Separated tannins were analysed using electrospray ionization mass spectroscopy (ESI MS) and nuclear magnetic resonance spectroscopy (1H NMR). Due to lack of time the tannins for structural analysis were not completely pure which hindered an accurate structure determination. By comparing our structural data with data from the literature possible structures of the isolated tannins were suggested, but further analysis is needed for unambiguous determination. However it is concluded that the dried Geum urbanum L. stems contains tannins which can be extracted with the method used.

UddannelserKemi, (Bachelor/kandidatuddannelse) Bachelor el. kandidat
SprogEngelsk
Udgivelsesdato17 jun. 2011
VejlederePoul Erik Hansen

Emneord

  • NMR
  • Hydrolysable tannins
  • Oxidative damage
  • Experiment
  • ROS
  • ESI-MS
  • Geum urbanum L.
  • Extraction
  • Column chromatography
  • Condensed tannins