MAO-A inhibitory activity of quercetin from Calluna vulgaris (L.) Hull

J Ethnopharmacol. 2009 Jan 12;121(1):178-81. doi: 10.1016/j.jep.2008.10.012. Epub 2008 Nov 1.


Aim of the study: This study investigated MAO-A inhibitory activity of methanol extract of Calluna vulgaris (L.) Hull., which traditionally has been used as a nerve calming remedy.

Materials and methods: A methanolic extract of Calluna vulgaris was partitioned against heptane, ethyl acetate and water. The three fractions were tested in a photometric peroxidase linked MAO-A bioassay. The ethyl acetate phase showed the highest MAO-A inhibitory activity. Quercetin was isolated by VLC through bioassay-guided fractionation and purified by re-crystallisation. The structure was elucidated by LC-MS and (1)H NMR.

Results: The IC(50)-value for MAO-A inhibition by quercetin was 18+/-0.2 microM in an assay where the IC(50)-value for MAO-A inhibition by clorgylin was 0.2+/-0.02 microM.

Conclusion: The content of quercetin in Calluna vulgaris might explain the reported nerve calming effect of the plant.

MeSH terms

  • Anti-Anxiety Agents / chemistry
  • Anti-Anxiety Agents / pharmacology*
  • Calluna / chemistry*
  • Chromatography, High Pressure Liquid
  • Chromatography, Liquid
  • Magnetic Resonance Spectroscopy
  • Mass Spectrometry
  • Monoamine Oxidase Inhibitors / chemistry
  • Monoamine Oxidase Inhibitors / pharmacology*
  • Plant Components, Aerial / chemistry
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Quercetin / chemistry
  • Quercetin / pharmacology*


  • Anti-Anxiety Agents
  • Monoamine Oxidase Inhibitors
  • Plant Extracts
  • Quercetin