Antibacterial and anti-inflammatory activities of some plants used for medicinal purposes in Kenya.

Aqueous, hexane and methanol extracts of 12 plant species, traditionally used in Kenya for treatment of ailments of infectious and/or inflammatory nature were screened for in vitro antibacterial and anti-inflammatory activities. Antibacterial activity was tested using the agar diffusion method while anti-inflammatory activity was tested using the cyclooxygenase (COX-1) assay. All the antibacterial activity was against Gram-positive bacteria with nine plant species showing some activity against Staphylococcus aureus. The highest activity was found in the methanol extracts of Maytenus senegalensis, Plectranthus barbatus, Zanthoxylum chalybeum, Zanthoxylum usambarense and hexane extracts of Spiranthes mauritianum. All the plant species showed some anti-inflammatory activities. In most cases, methanol extracts caused higher inhibition than aqueous and hexane extracts.