Qualitative Phytochemical Screening and In Vitro Antimicrobial Activities of Solanum americanum mill.
The use of plants as medicine is an ancient practice common to all societies especially the African societies and particularly some part of Northern Nigeria. Solanum americanum leaf sample was collected at Kona Road Garden, Bakin Kogi, Jalingo, Nigeria. The plant material was air-dried under shade and pulverized into coarse powder. After extraction with reflux apparatus for four hours using 70% methanol, the air-dried concentrated extract was then subjected to phytochemical evaluation and subsequent antimicrobial activities against some pathogenic microorganisms: Bacillus subtilis, Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Candida albicans using standard methods of analyses. The phytochemical results of the crude extract revealed the presence of alkaloids, anthraquinones, cardenolides, saponins, tannins and flavonoids. The antimicrobial activity of the plant extract was assayed using disc diffusion technique. The crude extract of S. americanum had the highest zone of inhibition of 15.00±0.00 mm against Candida albicans while the least inhibition zone of 7.33±0.47 mm was found against Streptococcus pyogenes. Other microorganism Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Klebsiella pneumoniae were found to be resistant at all concentrations. These findings shows that S. americanum can only be effective against infections related to Candida albicans and Streptococcus pyogenes. Hence, the use of S. americanum in traditional medical practice for the treatment of some microbial-related infections.