GCMS and FTIR analysis of ethanol and methanol leave extract of Urena lobata (Caesar weed) for bioactive phytochemical constituents

Abstract

This study was designed to apply the highly sophisticated biological and chemical characterization techniques–(GC-MS) Gas chromatography-mass spectrometry and FTIR spectroscopy to screen for bioactive phytocompounds present in ethanol and methanol extracts of U. lobata .The leaves of the plant were collected from a farm in Umuode village in Osisioma Ngwa local government area of Abia state, Nigeria. Ethanol and methanol extracts of the leaves were prepared and analyzed using Buck M910 Gas chromatography system with HP-5MS column (30m in length x250µm in diameter x 0.25µm in thickness film). Analysis of functional groups in the phytocompounds were done using Buck scientific M530 USA FTIR.12 vibrational functional groups were revealed by the FTIR screening in the ethanol and methanol extracts of U. lobata leaves. Some of the functional groups were indicative of alcohols, phenols, aromatic compounds, unsaturated hydrocarbons, vinyl ethers, amines, isonitriles and aliphatic compounds. GC-MS analysis of the ethanol leaf extract revealed 41 bioactive compounds with the following being most abundant, 9-octadecenoic acid(16.8%), dodecenoic acid(13.43%),n-hexadecanoic acid(11.73%), octadecanoic acid (9.78%), 1-docosene(9.57%) while the methanol extract revealed 47 bioactive compounds with the following having the highest abundance, n-hexadecanoic acid (26.65%) and (9.11%), dodecanoic acid(6.89%), 1-docosene(6.06%), erucic acid(4.09%).These phytocompounds and many others present in the leaf have been reported to possess multiple therapeutic activities. This therefore explains the use of this leaf in ancient medicine to treat numerous disease conditions. It further implies that the leaf could be exploited for the formulation of therapeutic molecules.
 Keywords: Urena lobata, GC-MS, FTIR, Spectroscopy, Phytocompounds, Functional group, Phytoconstituents