Phytochemical Investigation On The Root Of Rhynchosia MinimaLinn

Abstract

The root of the medicinal plant, Rhynchosia minima, was subjected to solvent extraction using methanol. The crude methanol extract was dissolved in distilled water and then subjected to solvent-solvent partitioning using hexane, chloroform, ethylacetate and methanol. The methanol extract was then subjected to phytochemical screening tests following standard methods which led to identification of alkaloids, flavonoids, Saponins, tannins and steroids in the crude extracts. After repeated CC the methanol extract afforded two tripterpene saponins, whose structures were elucidated by using IR, 1H and 13C NMR techniques as 2-[5,4-dihydroxy-2-hydroxymethyl-6-(4,4,6α,6β,8α,11,11,14β-octamethyl- 1,2,3,4,4α,5,6,6β,7,8,8α,9,10,11,12β,13,14,14α,14β-eicosahydro-picen-3-yloxy)-tetrahydropyran- 3-yloxy]-6-hydroxymethyl-tetrahydropyran 3,4,5-triol, (Rhynchosiaside-2) and (2, 2,6α,6β,9,9,12α-Heptamethyl-10-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydo-pyranylo, xy)-3,4,5,6,6α,6β,7,8,8α,9,10,11,12,12α, 12β,13,14,14α-octadecahydro-2Hpicene-4α carboxylic acid (Rhynchosiaside-1). It is reported that R. minima is used in folk medicine for the treatment of venereal diseases, internal inflammation, tumorous out growths, stomach ailments and lethargy in cattle. Therefore, antimicrobial assay of the methanol extract of root of R. minima was performed on three bacterial pathogens; viz. Klebsiella pneumonia, Escherichia coli and Staphylococcus aurous. The results showed that the root of R. minima contain some components such as saponins, tannins, steroids and triterpenoids. These compounds may not contribute for inhibiting effect against tested microorganisms.