Antibacterial and antifungal activities of extracts of Zanthoxylum chalybeum and Warburgia ugandensis, Ugandan medicinal plants
Abstract
Measles is a killer disease of children in Uganda. The treatment of the disease is mainly directed at the secondary microbial infections. A large proportion of the population in Uganda still relies on the use of herbal remedies, which have been claimed to produce beneficial responses. In this study, the efficacy of Warburgia ugandensis and Zanthoxylum chalybeum against common bacteria and fungi was investigated. Bactericidal and antifungal assays were done using extracts derived from Z. chalybeum and W. ugandensis (agar well diffusion, disc diffusion and colony count assays). All extracts (ethanolic, petroleum ether and aqueous) of Z. chalybeum did not show antimicrobial activity. Phytochemical investigations of Zanthoxylum chalybeum (seed) yielded a pure crystalline alkaloid (27-135D) which was characterized as skimianine based on 1H-NMR spectroscopy and comparison with spectra of authentic samples. Skimmianine did not have antimicrobial activity in this test system. W. ugandensis water extracts elicited antibacterial activity against both Escherischia coli and Staphylococcus aureus in the agar well assay but not in the disc diffusion assay. Warburgia ugandensis water extracts and fraction 27-163D also showed antifungal activity against Candida albicans. Chromatography of extracts of Warburgia ugandensis stem bark afforded compound 49-169K, which was characterized as the sesquiterpine muzigadial (by 1H-NMR spectroscopy), which did not show antibacterial activity but had antifungal activity against C. albicans. Therefore, the claimed efficacy of W. ugandensis could be attributable to antibacterial and antifungal activity of its components. Since Z. chalybeum extracts had neither antifungal nor antibacterial activities, its mode of action is unclear from these results.African Health Sciences 2001; 1(2): 66-72
While African Health Sciences has been freely accessible online there have been questions on whether it is Open Access or not. We wish to clearly state that indeed African Health Sciences is Open Access. There are key issues regarding Open Access needing clarification for avoidance of doubt:
- 1. Henceforth, papers in African Health Sciences will be published under the CC BY (Creative Commons Attribution License) 4.0 International. See details on https://creativecomons.org/)
- 2. The copyright owners or the authors grant the 3rd party (perpetually and in advance) the right to disseminate, reproduce, or use the research papers in part or in full, format/medium as long as:
- No substantive errors are introduced in the process
- Attribution of authorship and correct citation details are given
- The referencing details are not changed.
Should the papers be reproduced in part, this must be clearly stated.
- 3. The papers will be freely and universally accessible online in an easily readable format such as XML in at least one widely recognized open access repository such as PUBMED CENTRAL.
B. ABRIDGED LICENCE AGREEMENT BETWEEN AUTHORS AND African Health Sciences
I submitted my manuscript to African Health Sciences and would like to affirm that:
1.0 I am authorized by my co-authors to enter into these arrangements.
2.0 I guarantee, on behalf of self and co-authors:
- That the paper is original, and has not been published in any other peer-reviewed journal; nor is it under consideration by other journal (s). It does not infringe existing copyright or any other person’s rights
- That we are/I am the sole author(s) of the paper and with authority to enter into this agreement. My granting rights to African Health Sciences is not in breach of any other obligation
- That the paper contains nothing unlawful, or libelous. Nor anything that would constitute a breach of contract, confidence or commitment given to secrecy, if published
- That I/we have taken care to ensure the integrity of the article.
3.0 I and all co-authors, agree that the paper, if accepted for publication, shall be licensed under the Creative Commons Attribution License 4.0. (see https://creativecommons.org/)