Aspilia africana (Pers.) C.D.Adams is used in herbal medicine for the perceived presence of some bioactive
components in the leaves. Scientific reports suggest that different crude extracts
of the plant contain specific bioactive constituents that could have varied effects
on its biological activities. This study evaluated the phytochemical activities in
the meal; aqueous, chloroform and ethanolic extracts of A. africana leaves. The anti-microbial activity of the four samples of A. africana were tested on nine micro-organisms of six bacteria and three fungal strains using
the agar well diffussion technique. Results of the phytochemical screening and subsequent
quantification revealed the presence of high amount of some bioactive compounds; saponins,
tannins, alkaloids, flavonoids, terpenoids and phenols, but the absence of steroids
(leaf meal and all extracts), phylobatannin (chloroform and ethanolic extracts) and
cardiac glycoside (ethanolic extract) in the A. africana leaf products. Though the chloroform leaf extract had higher concentrations (P<0.05)
of these phytochemicals, significant (P<0.05) improvements were observed in the chemical
composition of the aqueous and ethanolic extracts. The anti-microbial activities observed
indicated that biological activities were dependent on the types of extractants and
the concentrations of principles present such as alkaloids and tannins. These activities
were comparable to those obtained for ampicillin and gentamycin. The susceptibility
of the microorganisms to the different A. africana leaf samples demonstrated its anti-bacterial and anti-fungal potentials and validated
its use as an anti-microbial agent in ethnoveterinary medicine. Further investigations
are required on their efficacies as phytobiotics in animal production.
