Phytochemical and Antibacterial Investigation of Leaf Extracts of Vernonia amygdalina
Aliyu Ibrahim Yar’adua
Department of Biochemistry, Umaru Musa Yar’adua University, P. M. B. 2218 Katsina, Nigeria.
Lawal Shuaibu *
Department of Pure and Industrial Chemistry, Federal University Birnin Kebbi, P. M. B. 1157, Birnin Kebbi, Nigeria.
Abdullahi Nasir
Department of Biochemistry, Umaru Musa Yar’adua University, P. M. B. 2218 Katsina, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Vernonia amygdalina was assessed for phytochemicals. The results showed that the leaf extract of the plant possessed the biologically active substances; cardiac glycosides, alkaloids, saponins and tannins. The presence of these bioactive constituents has been linked to the antimicrobial activity of the plant. The disc diffusion method was used to determine the antimimicrobial activity against Staphylococcus aureus, Proteus vulgaris, Escherichia coli, Pseudomonas aeroginosae, Streptococcus species, Klebsialla pneumoniaand Salmonella typhi. Aqueous extract of the leaves showed antimicrobial activity against all the tested bacteria with the exception of Proteus vulgaris in the order of sensitivity as Klebsialla pneumonia> Pseudomonas aeroginosae> Staphylococcus aureus> Salmonella typhi> Escherichia coli> Streptococcus species. The leaves of Vernonia amygdalina can be used as a source of oral drugs to fight infections caused by susceptible bacteria.
Keywords: Vernonia amygdalina, antimicrobial activity, phytochemical, alkaloids, saponins, tannins, cardiac glycosides