Chemical composition of the light petroleum extract of Hibiscus cannabinus bark and core

GC/MS studies of the light petroleum extracts obtained from different morphological regions of kenaf (Hibiscus cannabinus) showed large differences between the composition of the bark and of the core. The non-polar lipid constituents were essentially fatty acids (30.7 % in bark; 53.3 % in core), long chain alcohols (19.3 % in bark), alkanes (22.0 % in bark), sterols (12.5 % in bark; 25.4 % in core) and triterpenes (11.2 % in bark). Octacosanyl eicosanoate (15.7 %) was detected only in the bark extract and was identified by NMR and MS experiments, and by GC/MS after transesterification. Motiol, stigmast-4-en-3,6-dione (both reported here for the first time in the genus Hibiscus), beta -sitosterol and stigmast-4-en-3-one were isolated by TLC and their structures confirmed by NMR experiments and by MS. The NMR structural characterisations reported permit the correction of some previously recorded C-13 NMR data. Copyright (C) 2000 John Wiley & Sons, Ltd.