Phytochemical and antimicrobial screening of three Nigerian medicinal plants used to treat infectious diseases traditionally

Abstract

Three medicinal plants: Carpolobia lutea, Curculigo pilosa and Strophanthus hispidus used in the treatment of infectious diseases and other ailments traditionally were screened for secondary metabolites and antimicrobial activity. All the three plants contained saponins; C. lutea and S. hispidus contained cardenolides, while only C. lutea contained alkaloid in detectable quantity. Using agar cup diffusion method the crude extracts of the plants inhibited most of the test organisms: Staphylococcus aureus NCTC 6571, Bacillus subtilis, Escherichia coli NCTC 9001, Pseudomonas aeruginosa NCTC 6570, Aspergillus niger and Candida albicans at concentrations 10-100mg/ml. S. hispidus extracts were the most active. The study has demonstrated the antimicrobial potential of the plants and the basis for their inclusion in herbal preparations used to treat infectious diseases