IR and UV Analysis oF VLC Fractions Derived from Ethylacetate Extracts from the Roots of Maranthes Polyandra

Abstract

The research work was aimed at examining the medicinal value of the root of the plant, Maranthes polyandra as well as isolation and analysis of secondary metabolites using available spectroscopic techniques. The roots of M. polyandra were collected, dried, crushed and extracted with ethyl acetate via cold extraction method. The crude extract was fractionated using Vacuum Liquid Chromatography (TLC grade silica gel as the stationary phase and solvents of increasing polarity as mobile phase) and monitored using Thin Layer Chromatography. Fractions with similar TLC Rf values were pooled together and assigned Pool Number 1 to 14. White crystals were observed for pool number 4 – 11 and relabeled A – H. The crystals isolated were subjected to melting point, IR and UV spectroscopic analysis. Preliminary phytochemical screening of the ethyl acetate root extracts revealed the presence of alkaloids, cardiac glycosides, saponins, sterols, terpenoids, and tannins which are responsible for the therapeutic effects of M. polyandra in African traditional medicine. IR analysis showed characteristic absorption bands at 3440-3200 cm-1, 1705-1760 cm-1, 1680-1600 cm-1, and 1300-1000 cm-1 which are indicative of the presence of hydroxyl (–OH), carbonyl (C=O), alkene/aromatic (C=C) and ester (C-O) functional groups respectively. Other absorption bands include: 3000-2850 cm-1, 3100-3000 cm-1, 1470-1370 cm-1 and 900-690 cm-1 which depicts Sp3 C-Hstr (asymmetric and symmetric), Sp2 C-Hstr, C-Hbend of alkanes and C-Hbend of aromatics respectively. UV analysis showed major absorption bands at longer wavelengths (> 300 nm) and shorter wavelengths (< 250 nm). This can be attributed to n → π* and π → π* transitions respectively which is characteristic of carbonyl functional groups. The m.pt of the white crystals isolated ranged between 141 – 173 OC.