Anti-mycobacterial activity of five plant species used as traditional medicines in the Western Cape Province (South Africa).
BACKGROUND
Five plants used in traditional medicine in the Western Cape Province of South Africa, have been investigated for anti-mycobacterial activity: Olea capensis, Tulbaghia alliacea, Dittrichia graveolens, Leysera gnaphalodes and Buddleja saligna.


OBJECTIVE
The aim was to assess antimycobacterial activity in plants used in treatment of symptoms of TB, and through activity-guided fractionation of extracts to isolate compounds or mixtures with potential as anti-TB drug leads.


METHODS
Extracts and derived fractions were assayed against strains of Escherichia coli, Staphylococcus aureus, and Mycobacterium aurum A+. Isolated pure compounds were further tested against Mycobacterium species M. avium ATCC 25291, M. scrofulaceum ATCC 19981, M. microti ATCC 19422 and Mtb H37Rv, and for cytotoxicity against Chinese hamster ovarian cells.


RESULTS
Extracts of B. saligna and L. gnaphaloides exhibited significant anti-mycobacterial activity, primarily associated with the presence of non-cytotoxic triterpenoids oleanolic acid in B. saligna and both oleanolic and ursolic acids in L. gnaphaloides.


CONCLUSIONS
Anti-mycobacterial activity of extracts of selected plants is consistent with their traditional use. The identification of oleanolic and ursolic acids in these plants, and verification of their activity, underlines the potential for exploring structure-activity relationships of derivatives of these ubiquitous triterpenoids.
Bamuamba
Kapinga
K
Department of Molecular and Cell Biology, University of Cape Town, Rondebosch 7701, South Africa.
Gammon
David W
DW
Meyers
Paul
P
Dijoux-Franca
Marie-Genevieve
MG
Scott
Gillian
G
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002855:Chromatography, Thin Layer; D003124:Colorimetry; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D016488:Medicine, African Traditional; D008826:Microbial Sensitivity Tests; D009161:Mycobacterium / Q000187:drug effects*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D013019:South Africa; D021241:Spectrometry, Mass, Electrospray Ionization; D013778:Tetrazolium Salts; D013844:Thiazoles
D000900:Anti-Bacterial Agents; D010936:Plant Extracts; D013778:Tetrazolium Salts; D013844:Thiazoles; C022616:thiazolyl blue