Comparison of chemical compositions of essential oils from the fresh and dried leaves of Tapinanthus bangwensis (Engl. and K. Krause) Danser [Loranthaceae]

Abstract

The essential oil of T. bangwensis(Loranthaceae)leaves was obtained by hydrodistillation and the essential oilschemical constituents were analysed by gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS).Volatile oils were obtained differently from fresh and dried leaves of T. bangwensis in yields of 0.76% and 0.67% (v/w) respectively. A total of ten and ninecompounds representing 99.9% and 99.8% of the total oil contents were identified respectively from the fresh and dried samples. Major constituentsin the freshleavesare pentacosane (18.4%) heptacosane (12.5%), hexacosane (12.5%), heneicosane (12.4%), tetracosane (10.5%), and octacosane(10.4%) while the dried leaves consist mainly of (Z)-9-octadecenamide (27.9%), n-hexadecanoic acid (13.8%), pentadecane (12.5%), hexadecane (11.2%) and tetradecanamide (11.2%). It was found that n-hexadecanoic acid was present in both samples though in different percentage. The oil constituents of fresh sample were found to be majorly hydrocarbons while amide was found to be the major constituent of the dried sample.