ISOLATION WITH CHARACTERIZATION OF COLUMBIN AND NOVEL CLERODANE FURANO-DITERPENE WITH GC-MS AND ANTIMICROBIAL ANALYSES OF ESSENTIAL OILS FROM Sphenocentrum jollyanum Pierre

Abstract

jollyanum Pierre, was subjected to partition chromatography in gradient elutions, using vacuum liquid chromatography (VLC) and HPLC techniques. It led to the isolation of two compounds labelled as DO5d-2 and DO6, whose structures were determined by complete analyses of their spectroscopic data, utilizing modern techniques (LC-MS, 1H- and 13C-NMR, DEPT-NMR, HSQC, HMBC, COSY and NOESY). The Essential oils of the leaf and stem were extracted by hydro-distillation using Clevenger-typed apparatus and analysed by GC-MS technique. It was subsequently subjected to antimicrobial analysis using the agar diffusion method. The major isolated compound – DO6, was further characterized as ‘columbin’, while DO5d-2 was characterized as a new clerodane type furano-diterpene, which has not been previously reported. Essential oils obtained by hydro distillation from leaf and stem of Sphenocentrum jollyanum Pierre, were dominated by aldehydes in 10.93% and 15.14% respectively. Fifty (50) compounds were identified in leaf oil comprising 68.73% of it, with phytol (6.62%) and n-hexanol (6.28%) as most abundant compounds. Twenty-eight (28) compounds identified in the stem oil comprised 44.90% containing pentadecanal (14.72%) and phytol (6.38%) as its prominent compounds. The antimicrobial result showed the oil from the leaf was active against all the bacterial and fungi tested, while that from the stem revealed moderate activity against the tested bacterial and fungi.