TITLE:
Chemical Compositions of Lonchocarpus cyanescens Benth., (Fabaceae)—Case Study of Its Volatile Oils, and Two Triterpenoids
AUTHORS:
Dorcas Olufunke Moronkola, Ibrahim Adebayo Oladosu
KEYWORDS:
Lonchocarpus cyanescens; Fabaceae; Antimalaria; Phytochemistry; Essential Oils; GC, GC-MS, HPLC, IR, 1H and 13C-NMR
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.8,
August
5,
2013
ABSTRACT:
Leaf and stem
essential oils of Lonchocarpus cyanescens Benth., (Fabaceae) were obtained by hydro-distillation, using all-glass
apparatus adapted to British Pharmacopeia specifications with yields of 0.03%
and 0.17% respectively. The oils were investigated by GC and GC-MS analyses.
Results show seven compounds were responsible for 90.4% of leaf; eleven compounds
responsible for 97.6% of stem volatile oils. Phytol (62.5%) and hexadecanoic
acid (12.4%) dominate the leaf oil; octadecenoic (24.1%) and hexadecanoic acids
(17.2%) are predominant in the stem oil. Phytochemical screening of stem, leaf,
and root methanol extracts of Lonchocarpus
cyanescens reveal presence of following seven classes of metabolites:
saponin, tannin, steroid, terpenoid, cardiac glycosides, phlobatannins and
flavonoids. Partitioning of methanol extract from dried leaf of it with ethylacetate
gave fraction, which was chromatographed using gradient elution. TLC with high
Rf was used in monitoring elution. Two white crystalline
solids eluted at 5% and 10% ethylethanoate in hexane, were re-crystallized
and characterized. They were subjected to Infra-Red spectra, mass spectrometry
(ESI technique), 1H and 13C-NMR
analyses, which confirmed they are triterpenoids. Above mentioned metabolites may be
responsible for literature acclaimed bio-activities L. cyanescens display [anti-inflammatory, anti-arthritic, anti-microbial
effects]. This paper presents details of above results which are new in literature.