Comparative Chemical Study and Cytotoxic Activity of Uvariodendron angustifolium Essential Oils from Benin Jean-Pierre Noudogbessi 1 , Magali Gary-Bobo 2 , Aristide Adomou 3 , Elvis Adjalian 1 , Guy Alain Alitonou 1 , Félicien Avlessi 1 , Marcel Garcia 2 , Dominique C. K. Sohounhloue 1 and Chantal Menut 2* 1 Université d’Abomey-Calavi, Ecole Polytechnique d’Abomey-Calavi, Laboratoire d’Etude et de Recherche en Chimie Appliquée (LERCA), 01 BP 2009 Cotonou, Benin 2 Institut des Biomolécules Max Mousseron, UMR 5247, Equipe « Glyco et nanovecteurs pour le ciblage thérapeutique », Faculté de Pharmacie, 15 Avenue Charles Flahault, BP 14491, 34093 Montpellier, France 3 Herbier National, Département de Botanique, Faculté des Sciences et Techniques, Université d’Abomey-Calavi, République du Bénin chantal.menut@univ-montp2.fr Received: October 27 th , 2013; Accepted: November 19 th , 2013 This study aimed to compare the chemical composition of volatile extracts obtained by hydrodistillation of leaves, stems, bark and roots of Uvariodendron angustifolium (Engl. & Diels) R. E. Fries. The essential oils, obtained with yields between 0.12 and 0.66%, were analyzed by GC/FID and GC/MS. A great variability in the chemical composition was observed depending on the plant part treated. The essential oils obtained from leaves and stems contained mainly neral (29.7-30.5%) and geranial (42.9-47.3%), while methyl eugenol was the major component of the volatile extracts from bark (68.3%) and roots (85.3%). Interesting cytotoxic properties of these essential oils on human breast cancer cells MCF-7 were demonstrated. Keywords: Uariodendron angustifolium, Citral, Methyl eugenol, Cytotoxic properties, IC 50 . Uvariodendron angustifolium, syn. Uvaria angustifolia (Annonaceae), is a West African forest tree which can reach 15-40 ft high [1]. This species, which is found in the south of Benin, is used in traditional medicine to treat rheumatics, gastric ailments, and paludism, as well as for flavoring local dishes (leaves) [2]. The only chemical investigations of the Uvariodendron genus concern two species: U. connivens, which is characterized by phenylpropanoid compounds in its seeds (elemicin, cinnamaldehyde and 3,4,5-trimethoxy cinnamyl alcohol) [3] and U. calophyllum, which furnished, by hydrodistillation of its wood, stem bark and roots, essential oils rich in sesquiterpenes (mainly (E)-β- caryophyllene and α-santalene) [4]. To the best of our knowledge, no phytochemical studies have been undertaken on U. angustifolium; furthermore, no study has been reported on the cytotoxic character of U. angustifolium essential oil and its major compounds, in particular on MCF-7. However, in the literature, the antiproliferative properties of some essential oils have been described [5-9]. The present article reports the results of our chemical investigations on the oils obtained from different parts of U. angustifolium and their potential antiproliferative properties on human breast cancer cells MCF-7. The oils were obtained with the following yields (w/w vs fresh material): 0.12% for the stems; 0.14% for the stem-barks; 0.54% for the roots and 0.66% for the leaves. The combination of capillary GC/FID and GC/MS analysis allowed the identification of 28 to 43 components in the U. angustifolium leaf, stem, stem-bark and root essential oils, which accounted respectively for 95.9%, 98.4%, 97.2% and 98.8% of the whole composition (Table I). The essential oils obtained from leaves and stems were characterized by high proportions of oxygenated monoterpenes (81.4% and 87.0%), while the stem-bark and root essential oils contained high amounts of aromatic oxygenated compounds (75.4% to 89.3%). Indeed, the essential oils from leaves and stems were mostly dominated by citral (geranial: 42.9-47.3% and neral: 29.7-30.5%), whereas those from stem-bark and root were dominated by (E)-methyl eugenol (68.3% and 85.3% respectively). The accurate concentrations of these two major compounds were determined by a method based on the calculation of response factors [10]. The concentrations obtained were respectively 74.5% for citral (neral + geranial) in leaf essential oil and 88% for methyl eugenol in root oil, whereas these values were evaluated by the normalization method at respectively 73.4% and 85.3% (Table 1). As reported in the literature, the oxygenated compounds tend to produce a high response factor [11]. These compounds were accompanied by less significant percentages of other constituents such as (E)-methyl isoeugenol (5.2%), selin-11-en-4-α-ol (3.5%) and caryophyllene oxide (2.7%) in the stem-barks, linalool (3.1%) in the stems, camphene (2.9%) in the roots, and geraniol (2.0-2.3%) in the leaves and stems. Finally, the predominant constituents of the essential oils extracted from U. angustifolium do not correspond with the aromatic compounds (elemicin; 3,4,5-trimethoxycinnamaldehyde; 3,4,5-trimethoxy cinnamyl alcohol) isolated from U. connivens seeds [3]. They also differ from the major components (α-santalene: 20.8-48.0%, β-caryophyllene: 8.5-32.5%, β-bisabolene: 4.0-8.9%, cis-α- bergamotene: 4.8-7.4%, caryophyllene oxide: 6.7-6.8%, β- bisabolol: 3.5-6.0%) identified in the volatile extracts of the wood, stem-barks and roots of U. calophyllum from Cameroon [4]. The cytotoxicity of the essential oils obtained from different parts of U. angustifolium was estimated on human breast cancer cells MCF- 7. The results revealed some difference in the MCF-7 cells behavior in the presence of various concentrations of U. angustifolium volatile extracts. The IC 50 values of the leaf, stem, stem-bark and root volatile extracts determined for that purpose were respectively 220; 270; 320 and 460 µg/mL (Figure 1). According to these values, the four essential oils tested were active on MCF-7 cells. Indeed, NPC Natural Product Communications 2014 Vol. 9 No. 2 261 - 264