Identification and quantification of betulinic acid

Abstract

Betulinic acid was identified in the bark and in the wood of Platanus acerifolia (plane) and of Betula pendula (white birch) by thin layer chromatography, gas chromatography (GC), GC coupled with mass spectrometry (MS), electrospray ionisation MS, and 1H-nuclear magnetic resonance spectroscopy. Quantitative analysis by GC after derivatisation under mild silylating conditions and using squalane as internal standard showed 3.3% betulinic acid in the cork of plane while the wood content was much lower. The bark of white birch contained 0.3% betulinic acid. Copyright © 1999 John Wiley & Sons, Ltd.