Abstract

The leaf and root extracts of Senna italica were screened for phytochemical properties and antibacterial activity using standard methods.  Alkaloids, steroids and flavonoids were detected in aqueous-methanol, n-hexane and aqueous extracts while tannins, glycosides and saponins were not detected in all the extracts.  Sensitivity testing of the extracts showed a strong activity against all the test bacteria (Staphylococcus aureus, Salmonella typhi,Escherichia coli, Pseudomonas aeruginosa and Streptococcus pneumoniae), which increased with increasing concentration of the extracts (30, 60, 90 and 120 mg/ml). Thus, inhibition zones of 20.0 ± 0.82, 32.0 ± 0.50, 32.0 ± 0.50, 33.0 ± 1.64 and 31.25 ± 0.25 mm were recorded at the highest concentration of 120 mg/ml for the leaf extracts against S. aureus, S. typhi, E. coli, P. aeruginosa and S. pneumoniae respectively. Similar trend was observed for the root extracts. Therefore, on the ground of the pronounced activity of the extracts against the test bacteria as well as the presence of alkaloids, flavonoids and steroids in the extracts, it could be suggested that this plant has a potential as a source of therapeutic agents. This supports the traditional use of the plant in curing human diseases. It is therefore suggested that further studies be carried out using different solvents as well as to isolate, purify and identify the active compounds present in the extracts with a view to justifying these claims.

Key words: Senna italica, phytochemical screening, antibacterial activity, clinical isolates.