Composition and Chemical Variability of Ivoirian Xylopia staudtiiLeaf Oil

The chemical composition of a leaf oil sample from Ivoirian Xylopia staudtiiEngler & Diels (Annonaceae) has been investigated by a combination of chromatographic [GC(RI)] and spectroscopic (GC-MS, 13C NMR) techniques. Thirty-five components that accounted for 91.8% of the whole composition have been identified. The oil composition was dominated by the furanoguaiadienes furanoguaia-1,4-diene (39.0%) and furanoguaia-1,3-diene (7.5%), and by germacrene D (17.5%). The composition of twelve other leaf oil samples demonstrated qualitative homogeneity, but quantitative variability. Indeed, the contents of the major components varied substantially: furanoguaia-1,4-diene (24.7–51.7%) and germacrene D (5.9–24.8%). The composition of X. staudtiileaf oil is close to that of X. rubescensleaf oil but varied drastically from those of the essential oils isolated from other Xylopiaspecies. 13C NMR spectroscopy appeared as a powerful and complementary tool for analysis of sesquiterpene-rich essential oils.