Isoorientin, a Selective Inhibitor of Cyclooxygenase-2 (COX-2) from the Tubers of Pueraria tuberosa

Nat Prod Commun. 2015 Oct;10(10):1703-4.

Abstract

Bioassay-guided fraction of the methanol extract of the roots of Pueraria tuberose DC yielded puerarin, an isoflavone C-glycoside (PT-1), isoorientin, a flavone C-glycoside (PT-2) and mangiferin, a xanthone C-glycoside (PT-3). The extracts and the isolated compounds were screened for potent anti-inflammatory components inhibiting the cyclooxygenases (COX-1 and COX-2) and 5-lipoxygenase (5-LOX), the target enzymes of inflammation, by employing spectroscopic/polorographic methods. Among these, isoorientin was found to be a potent inhibitor of COX-2with an IC50 value of 39 μM. Docking studies were carried out to understand the interactions of isorientin (PT-2) with COX-2.The structures of the isolates were determined by mass spectrometry and 2D-NMR techniques including HSQC, HMBC, NOESY and 1H-1H COSY experiments. Although isoorientin and mangiferin have been reported from several plant sources, this is the first report of their isolation from a Pueraria species.

MeSH terms

  • Cyclooxygenase 2 / metabolism
  • Cyclooxygenase 2 Inhibitors / chemistry
  • Cyclooxygenase 2 Inhibitors / pharmacology*
  • Humans
  • Luteolin / chemistry*
  • Luteolin / pharmacology
  • Models, Molecular
  • Molecular Structure
  • Plant Tubers / chemistry*
  • Pueraria / chemistry*
  • Recombinant Proteins

Substances

  • Cyclooxygenase 2 Inhibitors
  • Recombinant Proteins
  • homoorientin
  • Cyclooxygenase 2
  • Luteolin