Antibacterial and cytotoxic activity of Kenyan medicinal plants

Antibacterial and cytotoxic activity of Kenyan medicinal plants

Wagate G Cyrus, Gakuya W Daniel, Mark O Nanyingi, Francis K Njonge, James M Mbaria

Department of Public Health, Pharmacology and Toxicology 1Department of Clinical Studies, Faculty of Veterinary Medicine, University
of Nairobi, PO Box 29053, 00625 Nairobi, Kenya 2Department of Chemistry, Jomo Kenyatta University of Agriculture and Technology,
Nairobi, Kenya

Abstract
Seven medicinal plant extracts traditionally used in Kenya, mainly for management of infectious conditions, were chosen and screened for their antibacterial activity against Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and Gram-positive (Bacillus cereus and Staphylococcus aureus) bacteria. Antibacterial activity was tested using the broth dilution method. Harrisonia abyssinica and Terminalia kilimandscharica extracts showed significant activity against Gram+ and Gram- bacteria. The methanolic extracts of T. kilimandscharica bark and H. abyssinica bark and leaves showed minimum inhibitory activity against all tested bacteria, with minimal inhibitory concentrations ranging from 25-150 mg/mL. Ajuga remota and Amaranthus hybridus, which are lethal to brine shrimp nauplii,
showed significantly lower antibacterial activity than those that were relatively non-toxic.

Key words: antibacterial - cytotoxicity - medicinal plants

link www.scielo.br/pdf/mioc/v103n7/04.pdf