Abstract

PHYTOCHEMICAL AND ANTIBACTERIAL ANALYSIS OF AQUEOUS AND ALCOHOLIC EXTRACTS OF VERNONIA AMYGDALINA (DEL.) LEAF

*Tsaku Alumbugu Paul, Ibrahim Taibat, Ekeleme Ike Kenneth, Nkenne Istifanus Haruna, Oti Victor Baba and Abimiku Rejoice Helma

Abstract

Medicinal plants offer an attractive array of phytochemicals with novel microbial disease – controlling potentials, due to the spectrum of secondary metabolites present in their extracts. The aim of this study was to investigate the phytochemicals present in leaf extracts of V. amygdalina and to examine its antibacterial properties against some clinical bacterial isolates. Ethanol, methanol and water were used as solvents in the extraction. The phytochemical screening showed that the ethanolic and aqueous extracts had tannins, flavonoids, alkaloids, saponins, phytate and oxalate in varying proportions while alkaloid was the only exclusion in the methanolic extract. The antibacterial activity of the ethanolic extract showed an average diameter inhibition zone between 9.0 mm to 24.0 mm against some clinical bacterial isolates such as, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Streptococcus pneumoniae and Klebsiella pneumoniae. The methanolic extracts showed significant level of activity against the bacterial isolates tested, with average diameter inhibition zones between 10.0 mm – 17.0 mm. The aqueous extracts showed antibacterial activity against the clinical bacterial isolates tested with average diameter inhibition of 9.0 mm – 19.0 mm. The plant leaf is recommended as a source of broad spectrum antibiotic for treatment of Gram positive and negative bacterial infections.

Keywords: Vernonia amygdalina, phytochemical, plant extract, antibacterial activity.