Chemical composition of leaf and bark essential oils ofVepris unifoliolatafrom Madagascar

The chemical composition of leaf essential oil of Vepris unifoliolata was characterized by hydrocarbon monoterpenes, α-pinene (60.5%), myrcene (6.8%), limonene (5.1%), (E)-β-ocimene (4.9%) and β-phellandrene (4.7%). The chemical composition of bark essential oil of V. unifoliolata was original and characterized by a high content in heat-sensitive compounds isofuranodiene (43.9%) and germacrone (17.1%). These compounds bearing the (E,E)-1,5-cyclodecadiene structure were known to rearrange and degrade during the GC–FID and GC-MS. The true content of isofuranodiene/curzerene, germacrone/trans-β-elemenone, germacrene A/β-elemene and germacrene B/γ-elemene was evaluated by combination of 13C-NMR data (intensities of signals of selected carbons) and GC–FID. Thus, a correct quantitative analysis of bark oil of V. unifoliolata was provided.