Chemical Characterization and Biological Activity of Flavonoids in Some Medicinal Plants

In this study Three plants species from eastern and western Sudan were studied: Namely Acacia nubica benth( Laot), Citrus paradise (grapefruit ) and Combretum Hartmonnina Schweinf (Habeel )The plant material was extracted using 95% ethanol.The crude extracts were subjected to a phytochemical screening which revealed the presence of flavonoids among other phytochemicals .The crude extracts were purified by thin layer chromatography utilizing different solvent systems ,and characterized using : IR,UV, HNMR and Mass spectroscopy . Aflalavonoid :7,5 ´ ,6 ´ - trihydroxy-5-methyl-isoflavone was isolated from the bark of Combretum Hartmonnina Schweinf (Habeel )5,7,4 ´ ,5 ´ -tetrahydroxy-6,8,1´ ,2 ´ ,6 ´ -pentamethoxyflavanone was isolated from the leaves of Acacia nubica and7-oglycosyl-5,4 ´ dihydroxyflavanone was isolated from the leaves of Citrus paradiseThe isolated flavonoids revealed promising antimicrobial potential.