Lipophilic Extractives of the Inner and Outer Barks of Eucalyptus globulus

Abstract

Summary The chemical compositions of the dichloromethane extracts of inner and outer barks of E. globulus were studied by gas chromatography-mass spectrometry. The two fractions show very different chemical compositions: triterpenic acids, such as betulinic, ursolic and oleanolic acids, were the major components of the outer bark extract, whereas β-sitosterol and β-amirin along with palmitic, linoleic and oleic acids predominate in the inner bark extract. Several α-and β-hydroxy fatty acids, recently reported for the first time as E. globulus wood components, were also identified in the outer and inner barks. In the outer bark extract, minor amounts of ferulic acid esters, also previously reported to occur in E. globulus wood were identified. In general, the inner bark lipophilic extractives resemble more closely that of E. globulus wood.