Jean-François Cavalli,* Félix Tomi and Joseph Casanova, Antoine-François Bernardini

Abstract: Six commercial samples of the essential oil of Tagetes bipinata from Madagascar were analyzed by GC (retention indices), GC/MS and 13C-NMR. Tagetes bipinata produces a monoterpene-rich oil dominated by (Z)-b-ocimene and acyclic unsaturated ketones among which dihydrotagetone was present in the six samples at appreciable content (11.9–24.4%) and is reported for the first time in the oil of T. bipinata.

Several species belong to the genus <i>Tagetes</i> (Asteraceae) and their essential oils and solvent extracts contain bioactive compounds (terpenoids, flavonoids, thiophenes, polythiophenes and pyrethroids) which have been reviewed (1,2), as well as the composition of <i>Tagetes</i> oils (3–5). Among <i>Tagetes</i> species, <i>Tagetes bipinata</i> L., a herbaceous plant is found in Madagascar, in savannas, along the verges of roads or in the areas more or less ruderalized (6). Locally, <i>T. bipinata</i> is named “Mavoadaladia” or “Tsipolibazaha” (7). Only one study reported on the composition of the essential oil of <i>T. bipinata</i>. All the samples of Malagasy origin, obtained from aerial parts, were dominated by (Z)-b-ocimene and unsaturated ketones, (E)- and (Z)-tagetenones, myrcenone, (E)-tagetone (7). As part of our ongoing studies on the characterization of aromatic plants from Madagascar through the composition of their essential oils (8-10), we investigated several samples isolated from <i>Tagetes bipinata</i>. The analysis has been carried out by combination of GC (Retention Indices), GC/MS and 13C-NMR spectroscopy.