Extracts obtained from the leaves, stem-bark and roots of two ethnomedicinal plants: Morinda lucida Benth and Trema guineensis Schumm and Thorn were screened for antimicrobial activities against eleven test organisms (five bacteria and six fungi) namely: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Bacillus subtilis, Candida albicans, Trichopyton tonsurans, T. rubrum, T. mentagrophytes, Basidobolus haptosporus and Aspergillus niger. The agar plate, cup-plate and broth dilution methods were used for the antimicrobial analysis. The minimal inhibitory concentrations (MIC) and the minimum biocidal concentrations (MBC) of the extracts were determined in vitro.The results showed that most of these extracts posses in vitro antimicrobial activities against the tested clinical isolates of bacteria and fungi. These antimicrobial activities have been attributed to the presence of some or all of the following secondary plant metabolites: alkaloids, tannins, saponins, flavonoids, steroids and glycosides. Key Words: Plant extracts, antimicrobial activities, medicinal plants, methanol. Bio-Research Vol.2(1) 2004: 39-46
EI Nweze, JI Okafor, O Njoku
