Constituents of leaf, stem bark and root volatile oils of <i>Anogeissus leiocarpus</i> DC. Guill. & Perr.

Abstract

We report volatile compounds in Anogeissus leiocarpus, which is scarce in literature. Here in Nigeria leaf, stem bark and root essential oils were obtained by hydro-distillation using Clevenger-type apparatus, analyzed by GC and GC-MS. 88% leaf oil comprised of eleven compounds, with abundance of z-9-octadecenoic acid (29.0), n-hexadecanoic acid (21.4), n-octadecanoic acid (12.7), methyl-7E-7-octadecenoate (8.5), and methylhexadecanoate (5.4). Thirteen compounds amount to 80% of the stem bark oil, its significant compounds being z-9-octadecenoic acid (22.8), n-hexadecanoic acid (20.8), methyl-9z-octadecenoate (12.4), methylhexadecanoate (7.8) and eicosane (4.1). Fourteen compounds make-up 91% of root oil, dominated by methyl-7E-7-octadecenoate (18.1), n-hexadecanoic acid (17.6), methyl linoleate (16.2),  z-9-octadecenoic acid (15.7) and methylhexadecanoate (14.2). Leaf, stem bark and root oils are characterized by the following classes of compounds respectively (%): fatty acids [65.8, 43.6, 36.7]; esters [17.9, 20.2, 49.9]; hydrocarbons [3.2, 15.7, 1.7]; leaf and root oils contain terpenoids [1.1, 1.1]; dl-arabinose (sugar) is in stem bark oil. Methylhexadecanoate and hexadecanoic acid are common to the three oils. They can serve as chemotaxonomic markers characteristic for this species. Compositions of Anogeissus leiocarpus three oils vary, are unique and of different chemo-types. This report is first of its kind in literature for ‘axlewood’ plant.

Keywords: Combretaceae, Anogeissus leiocarpus, essential oil, GC-MS.