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

<p>The chemical composition of twenty-five essential oil samples from the aerial parts of two Malagasy endemic species <i>Billburttia capensoides</i> Sales & Hedge and <i>B. vaginoides</i> 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: <i>p</i>-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 <i>p</i>-mentha-1,3,8-triene while the Group II was dominated by terpinolene and dill apiole.</p

Implications of a molecular phylogenetic study of the Malagasy genus Cedrelopsis and its relatives (Ptaeroxylaceae).

International audiencePtaeroxylaceae is an Afro-Malagasy family containing three genera, Bottegoa, Cedrelopsis, and Ptaeroxylon. Although the family is morphologically well delimited, it is currently considered part of the subfamily Spathelioideae in a broadly circumscribed orange family (Rutaceae). The Malagasy Cedrelopsis has traditionally been associated with different families of the order Sapindales and its phylogenetic placement in Rutaceae sensu lato has yet to be tested with molecular data. The present molecular phylogenetic study reaffirms the monophyly of Ptaeroxylaceae and its placement in Spathelioideae. Therefore, molecules and morphology support close affinities between Bottegoa, Cedrelopsis, and Ptaeroxylon and also their current generic circumscriptions. We report a case of an evolutionary change from one-seeded to two-seeded carpels within the Harrisonia-Cneorum-Ptaeroxylaceae clade of Spathelioideae. Finally, the sister-group relationship between the African Bottegoa and the Afro-Malagasy Ptaeroxylon-Cedrelopsis clade suggests an African origin of Cedrelopsis