Abstract

Medicinal plants contain a variety of chemical substances with important therapeutic properties that can be utilized in the treatment of human diseases. Hydonora africana is used in folklore remedies for the treatment of diarrhoea, dysentery, kidney and bladder complaints among other ailments; hence we assessed the in vitro antimicrobial activity of this plant against three bacterial species (Helicobacter pylori ATCC 43526, Helicobacter pylori PE 252C, Staphylococcus aureus NCTC 6571 and Aeromonas hydrophila ATCC 35654). The agar well diffusion method was used to determine the susceptibility of bacterial strains to crude extracts of the plant. The minimum inhibitory concentration (MIC₅₀) and minimum bactericidal concentration (MBC) of the active crude extracts were determined by the microdilution test. Ciprofloxacin (0.0125 mg/mL) was used as positive control. The presence of phytochemicals was also assessed using standard methods. Results were analyzed statistically by the one-way ANOVA test. Hydnora africana demonstrated antimicrobial activity against all the organisms with a mean zone diameter of inhibition ranging from 0 to 22 mm. The MIC₅₀ of the extracts ranged from 0.078 to 2.5 mg/mL and MBC ranged from 0.78 to 25 mg/mL. Phytochemical assay revealed the presence of alkaloids, tannins, flavonoids, saponins and steroids in the extracts. It is concluded that H. africana may contain compounds with therapeutic activity.

Key words: Hydnora africana, medicinal plant, minimum inhibitory concentration, minimum bactericidal concentration, phytochemicals.