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Published on: March 31, 2021
Antimicrobial compounds from Coleonema album (Rutaceae)
Lindy L Esterhuizen1, Riaan Meyer, Ian A Dubery
1Department of Biochemistry, Kingsway Campus, University of Johannesburg, P.O. Box 524, Auckland Park 2006, South Africa.
Zeitschrift Fur Naturforschung. C, Journal of Biosciences
|September 23, 2006
Summary
Coleonema album, a South African plant, exhibits potent antimicrobial activity against a broad spectrum of bacteria and fungi. Its extracts, rich in coumarin aglycones, show promise as a source for novel drug development.
Area of Science:
- Phytochemistry
- Microbiology
- Pharmacognosy
Background:
- Coleonema album is a plant species native to the South African fynbos biome.
- Secondary metabolites from medicinal plants are a rich source of novel therapeutic compounds.
- Antimicrobial resistance necessitates the discovery of new antimicrobial agents.
Purpose of the Study:
- To evaluate the antimicrobial activity of Coleonema album extracts.
- To identify the bioactive secondary metabolites responsible for the observed activity.
- To explore the potential of C. album as a source for new antimicrobial drugs.
Main Methods:
- Extraction of plant material using ethanol and acetone.
- Bioassay-guided fractionation and TLC-bioautography for activity screening.
- Serial microdilution assay to determine minimum inhibitory concentrations (MICs).
- Preparative TLC and LC-MS for identification of active compounds.
Main Results:
- C. album extracts demonstrated significant antimicrobial activity against all tested microorganisms, including Gram-positive bacteria, Gram-negative bacteria, and fungi.
- MICs were found to be in the low mg/mL range, indicating potent activity.
- Coumarin aglycones were identified as the primary compounds responsible for the antimicrobial effects.
Conclusions:
- Coleonema album possesses broad-spectrum antimicrobial properties.
- The identified coumarin aglycones are key contributors to the plant's bioactivity.
- Further research into C. album extracts and their constituents is warranted for potential drug development.
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