Antibacterial activity of Harungana madagascariensis leaf extracts.
Aqueous extracts of the leaf of Harungana madagascariensis were analysed phytochemically and evaluated for antimicrobial activity against strains of Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa. Glycosides, tannins, saponins, flavonoids and alkaloids were detected in the plant material. B. subtilis, E. coli and S. typhi, but not Ps. aeruginosa, showed susceptibility at MICs of 2.0 and 15.6 mg/mL; and MBCs of 2.0-3.9 mg/mL and 15.6-31.3 mg/mL, respectively, for the cold and hot extracts. Staph. aureus showed susceptibility only to the hot extract. Concentrations of 2.5-10.0 mg/mL of the cold extract killed over 7 log(10) of the test bacterial population within 30-60 min of exposure. The hot extract needed higher concentrations and longer treatment to achieve similar levels of bacterial cell killing. The results provide a rationalization for the traditional use of H. madagascariensis leaf extracts for the treatment of gastrointestinal disorders.
Okoli
A S
AS
Department of Microbiology, University of Nigeria, Nsukka, Enugu State, Nigeria.
Okeke
M I
MI
Iroegbu
C U
CU
Ebo
P U
PU
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects; D001419:Bacteria / Q000187:drug effects*; D002939:Ciprofloxacin / Q000494:pharmacology; D003080:Cold Temperature; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000187:drug effects; D005839:Gentamicins / Q000494:pharmacology; D006358:Hot Temperature; D016488:Medicine, African Traditional; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012485:Salmonella typhi / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects
D000900:Anti-Bacterial Agents; D005839:Gentamicins; D010936:Plant Extracts; D002939:Ciprofloxacin