Comparative study on the chemical composition of lipophilic fractions from three wood tissues of Eucalyptus species by gas chromatography-mass spectrometry analysis

摘要

Abstract The chemical compositions of lipophilic fractions from Eucalyptus urograndis and Eucalyptus urophylla cultivated in Brazil and Eucalyptus camaldulensis from Mexico were determined by gas chromatography-mass spectrometry (GC-MS) before and after alkaline hydrolysis followed by derivatization. In all fractions, fatty acids (including small amounts of α-and ω-hydroxy fatty acids) and sterols were the most abundant components followed by smaller amounts of long-chain aliphatic alcohols, phenolic acids, and hydrocarbons. The presence of steroid esters and triacylglycerols in all three species was indirectly confirmed by the increased amount of fatty acids and sterols (manly β-sitosterol) in the hydrolyzed fractions compared with the corresponding nonhydrolyzed fractions. The amount of liphophilic compounds (mainly fatty acids and sterols) identified in hydrolyzed fractions of E. urograndis, E. camaldulensis, and E. urophylla corresponded to 1921, 1915, and 634 mg kg−1 of dry matter, respectively. The lower abundance of fatty acids and sterols in the fractions from E. urophylla indicates that problems related to pitch formation will be less severe for this species than for the other two.