Chemical Characterization of Some Flavonoids from the Roots of Acacia seyal , Tamarindus idica and the leaves of Acacia albida and The Biological Activity of their Extracts

Abstract

In the present study three Sudanese medicinal plants Acacia albida, Acacia seyal and Tamarindus indica were investigated for their chemical constituents and their in vitro antimicrobial activity. Phytochemical analysis revealed the presence of flavonoids, tannins and saponins in all plants and the absence of steroids in all plants.Alkaloids and triterpenes were not detected in Acacia albaida and Tamarindus indica. The alcoholic extracts of the three plants produced inhibition zones in all test microorganisms (Staphylococus aureus, Bacillus subtilis, Psuedomonas aeruginosa,Escherichia coli and the fungal species Candida albicans and Aspergillus niger). Chromatographic fractionation over silica gel plates led to the isolation of three flavonoids (I – III) from the leaves of Acacia albida , roots of Acacia seyal and Tamarindus indica . The structures of the isolated flavonoids were determined through a series of spectroscopic techniques including IR, UV, NMR and MS.