In vitro antibacterial activities of three plants used in traditional medicine in Sierra Leone.

The antibacterial activities of the methanol and hot and cold aqueous extracts of the leaves of Aspilia africana, Ficus exasperata and Mareya micrantha were bioassayed against three Gram-negative and three Gram-positive bacterial species: Aerobacter aerogenes, Agrobacterium tumefaciens, Bacillus subtilis, Clostridium sporogenes, Escherichia coli and Staphylococcus aureus. The methanol and aqueous extracts of the leaves of Aspilia africana and Mareya micrantha and the undiluted oil of M. micrantha exhibited differential antibacterial activities on both Gram-positive and Gram-negative bacterial species at concentrations ranging from 0.1 to 0.5 g/ml. Extracts of Ficus exasperata leaves were inactive at all concentrations tested.