ABSTRACT
Background: The Jatropha curcas L.(Euphorbiaceae) herb is found in SouthWest; Nigeria and other parts of West Africa; and is claimed to possess anti-hypertensive property. Objective: The phytochemical screening and flavonoid quantification of the leaf extract of Jatropha curcas Linn were studied. Methods: The phytochemical screening of the methanolic leaf extract of J. curcas L. was carried using acceptable and standard methods. The flavonoid contents of the leaf extract of Jatropha curcas L. were determined using thin layer chromatography (TLC); infrared spectroscopy (IRS) and a reversed phase high performance liquid chromatography (HPLC). Results: The phytochemical screening of the methanolic extract of the leaves of the plant shows the presence of alkaloids; cardiac glycosides; cyanogenic glycosides; phlobatannins; tannins; flavonoids and saponins. To quantify the flavonoid contents of leaf extract of Jatropha curcas L ; extracts from the plant samples where examined in a C-18 column with UV detection and isocratic elution with acetonitrile; water (45:55). Levels of flavonoids (flavones) in leaves ranged from 6:90 to 8:85 mg / g dry weight. Conclusion : Results indicate that the methanolic extract of the leaves of Jatropha curcas L. contains useful active ingredients which may serve as potential drug for the treatment of diseases. In addition; a combination of TLC; IRS and HPLC can be used to analyse and quantify the flavonoids present in the leaves of Jatropha curcas L