A Toxicological Evaluation and Anti-Candidal Activity of Plants used by Women in Northern Maputaland (South Africa) for the Treatment of Gynaecology and Obstretrics Ailments
Loading...
Date
2021
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Zululand
Abstract
Medicinal plants still play an important role in the primary healthcare of lay people in northern Maputaland in spite of the availability of hospitals and clinics. According to an ethnobotanical survey conducted in 2014, the lay people in northern Maputaland use plant species independently and in combination to treat gynaecology and obstetrics medical conditions. These plant species were generally regarded as safe by the lay people except for one plant species, Trichilia dregeana. Consequently, this study’s aim was to investigate the safety of medicinal plant species used by the lay people in northern Maputaland. Furthermore, as these plant species were used to treat medical conditions specifically related to woman, the inclusion of the efficacy of these plant species against Candida stains was included due to the prevalence of vaginal thrush.
The aqueous and organic (1:1 methanol-dichloromethane) extracts were prepared from 51 plant samples (including leaf samples collected for potential substitution for the roots). Toxicology of these plants was assessed using the brine shrimp lethality assay (BSLA) and the Ames assay (using Salmonella typhimurium TA98 and TA100 strains) for mutagenicity. The anti-Candidal activity was assessed using the antimicrobial micro-dilution assay to determine the minimum inhibitory concentration of of the plant samples aginst Candida albicans ATCC 10231, C. tropicalis ATCC 750 and C. glabrata ATCC 900300.
There were three plant spescies (Acalypha villicaulis root, Grewia occidentalis root and Gymnosporia senegalensis leaves) that indicated neither toxicity nor mutagenicity in this study. All the toxic plants samples (in BSLA) were further subjected to two-fold dilution and demonstrated acceptable toxic concentrations, which were found to range from 0.98 to 0.10 mg/ml. However, Hermannia boraginiflora, Sapium integerrimum, Scadoxus puniceus and Tabernaemontana elegans remained toxic even after diluted to the lowest concentration of 0.031 mg/ml.
Plant species combinations that were found to be non-toxic in BSLA in both aqueous and organic extract were Euphobia tirucalli (root) + Ozoroa engleri (bark) + Scadoxus puniceus (bulb) + Senecio serratuloides (whole plant), Bridelia cathartica (root) +
iii
Opuntia stricta (stem) + Searsia nebulosa (bark) and B. cathartica (root) + Erythrina humeana (root).
In the Ames test, plant samples that appeared to be non-mutagenic against both S. typhimurium TA98 and TA100 strains were A. villicaulis root, Cyperus natalensis root, Euclea natalensis leaves, G. occidentalis root, Ochna natalitia leaves, S. integerrimum leaves and S. puniceus bulb. However, Hypoxis hemerocallidea and O. stricta appeared to be the most mutagenic against both the S. typhimurium TA98 and TA100 strains with both aqueous and organic extracts showing mutagenicity.
The antimicrobial microdilution assay indicated a small number of plant species that were active against Candida strains and were in most cases these were the methanoldichloromethane extracts. A moderate activity against C. albicans was observed with the aqueous extract of Euclea natalensis root and Rhoicissus digitata leaves. The methanol-dichloromethane extracs of O. stricta stem, P. africanum root and S. birrea stem were also active (moderately) against C. albicans. Against the C. tropicalis, a moderate activity was observed against A. villicaulis leaves, Acanthospermum glabratum whole plants, B. cathartica leaves, Cassytha filiformis whole plant, Euphorbia tirucalli stem and Garcinia livingstonei root. A noteworthy anti-Candidal activity was observed with Commiphora neglecta root and leaves both with the minimum inhibitory concentration (MIC) of 0.13 mg/ml against Candida tropicalis. There was no activity observed against C. glabrata.
This study has indicated that medicinal plant species may have toxic and/ or mutagenic effects, even without any noteworthy signs after consumption. However, it was determined that toxicity can be reduced by carefully managing the dose. The reduction of concentration is not known whether it may affect the efficacy, therefore further studies on the efficacy are recommended.
Description
A thesis submitted to the Faculty of Faculty of Science, Agriculture and Engineering in fulfilment of the requirements for the Degree Master of Science in the Department of Botany at the University of Zululand, South Africa, 2021.
Keywords
anti-Candidal activity, gynaecological, obstetrics ailments