Constituents in evening primrose oil with radical scavenging, cyclooxygenase, and neutrophil elastase inhibitory activities

J Agric Food Chem. 2002 Sep 25;50(20):5533-8. doi: 10.1021/jf025581l.

Abstract

Cold-pressed, non-raffinated evening primrose oil was found to contain lipophilic radical scavengers. A highly enriched fraction of these compounds could be obtained from the oil by extraction with aqueous ethanol and subsequent liquid-liquid partitioning with petroleum. LC-DAD-MS analysis revealed that the fraction contained three aromatic compounds with identical UV and ESI-MS spectra. The compounds were isolated by RP-HPLC and their structures established by chemical and spectroscopic means as 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid. The morolic acid derivative was a new compound. The three esters exhibited pronounced radical scavenging activity against the stable 2,2-diphenyl-1-picrylhydrazyl radical and were potent inhibitors of neutrophil elastase and cyclooxygenase-1 and -2 in vitro. Commercial samples of evening primrose oils contained only traces of these lipophilic antioxidants.

MeSH terms

  • Antioxidants / analysis
  • Betulinic Acid
  • Chromatography, High Pressure Liquid
  • Chromatography, Liquid
  • Cyclooxygenase Inhibitors / analysis
  • Cyclooxygenase Inhibitors / pharmacology*
  • Enzyme Inhibitors / analysis
  • Enzyme Inhibitors / pharmacology*
  • Esters / pharmacology
  • Fatty Acids, Essential / chemistry*
  • Fatty Acids, Essential / pharmacology*
  • Free Radical Scavengers / analysis
  • Free Radical Scavengers / pharmacology*
  • Leukocyte Elastase / antagonists & inhibitors*
  • Linoleic Acids
  • Mass Spectrometry / methods
  • Oenothera biennis
  • Oleanolic Acid / analysis
  • Pentacyclic Triterpenes
  • Plant Oils
  • Triterpenes / chemistry
  • gamma-Linolenic Acid

Substances

  • Antioxidants
  • Cyclooxygenase Inhibitors
  • Enzyme Inhibitors
  • Esters
  • Fatty Acids, Essential
  • Free Radical Scavengers
  • Linoleic Acids
  • Pentacyclic Triterpenes
  • Plant Oils
  • Triterpenes
  • morolic acid
  • evening primrose oil
  • Oleanolic Acid
  • gamma-Linolenic Acid
  • Leukocyte Elastase
  • Betulinic Acid