Chemical composition of the essential oils from the aerial parts of two Malagasy endemic species (Apiaceae): Billburttia capensoides Sales & Hedge and Billburttia vaginoides Sales & Hedge

: The chemical composition of twenty-five essential oil samples from the aerial parts of two Malagasy endemic species Billburttia capensoides Sales & Hedge and B. vaginoides Sales & Hedge, were investigated for the first time. Based on chromatographic profiles, three selected samples were investigated using GC(RI), GC-MS and 13C NMR. The content of the main components varied drastically from sample to sample: p-mentha-1,3,8-triene (0.2-52.7%), terpinolene (2.8-40.7%) and dill apiole (0.0-22.2%). Statistical analysis of the 25 oil compositions allowed the distinction of two well-differentiated groups. Samples of group I contained mainly p-mentha-1,3,8-triene while the Group II was dominated by terpinolene and dill apiole.