Abstract

Studies were carried out to investigate the effect of root extract from a tropical plant Synadenium glaucescens against two pathogenic species of bacteria in mice. A total of 120 mice were used in two experiments involving two bacterial species, Staphylococcus aureus and Pseudomonas aeruginosa. In each experiment, 60 mice were randomly divided into 6 groups with or without bacterial infection and with or without root extract. Clinical signs and survival of the mice were monitored; skin, kidneys and livers were examined for gross lesions, histopathological changes and bacterial counts. Results indicated that mice infected with the two bacteria and treated with the root extract from S. glaucescens had significantly less (P < 0.05) severe skin lesions compared to mice from the untreated groups. Histopathological examination of liver and kidney tissues showed hydropic degeneration and inflammatory reaction in uninfected groups receiving the extracts. Protein in tubular lumens, desquamated tubular epithelium and necrosis around central veins were observed in livers of mice infected with S. aureus and treated with the extract at 50 mg/kg body weight. It is concluded that root extract from S. glaucescens had significant antibacterial activity against the tested bacteria. Histopathological changes in the kidneys and livers of mice which received the extract alone suggested that high doses of the tested extract could be harmful to the mice. Further studies are needed to find out optimum dosage and whether the extract is harmful to other organs.

Key words: Synadenium glaucescens, root extract, antibacterial activity, mice.