Characterization of Some Flavonoids from Acacia nilotica subsp. adstringens Seed, Smilax regelii Root, Acacia seiberiana Stem, and Acacia tortilis Leave and Biological Activity of Fractions

Abstract

This study was designed to investigate the major flavonoids of four multipurpose medicinal plants (Acacia nilotica subsp. Adstrings seeds, Smilax regelii root , Acacia seiberiana stem, and Acacia tortilis leave). The flavonoids were extracted with 95% ethanol, and the crude extracts were purified by thin layer chromatography where four flavonoids ( I,II,III, and IV )were isolated and partially characterized by some spectral data (UV, H1NMR). Qualitative test on alcoholic extracts of these plants were done. Also different fractions (ethanol, chloroform, ethyl acetate and n- butanol) of these plants were assessed for antimicrobial activity. Extract of Acacia nilotica subsp. Adstringens seeds revealed the presence of flavonoids, alkaloids, tannins, steroids and carbohydrates. The n-butanol , ethanol, chloroform and ethyl acetate fractions showed moderate antimicrobial activity. The isolated compound I was assigned the following partial structure. I Extract of Smilax regelii roots revealed the presence of flavonoids, alkaloids, steroids and saponins. The ethyl acetate, chloroform, n-butanol and ethanol fractions showed significant activity against OOCH3OOHCH3CH3 v Staphylococcus aureus. The isolated compound II was assigned the following partial structure. II Extract of Acacia seiberiana stem revealed the presence of flavonoids, alkaloids, steroids , carbohydrates and saponins. The chloroform , nbutanol and ethyl acetate fractions showed significant to moderate antimicrobial activities . The isolated compound III was assigned the following partial structure. III Extract of Acacia tortilis leaves revealed the presence of flavonoids, alkaloids, steroids, carbohydrates, tannins and saponins. The ethyl acetate , ethanol, n-butanol and chloroform fractions showed different antimicrobial responses. The isolated compound IV was assigned the following partial structure.