Cussonia species (commonly known as Cabbage trees) are indigenous to South Africa and are used in traditional medicine to treat an assortment of diseases. Due to their attractive growth form, they are assets in gardens. However, there are no developed methods for propagating these species. The use of three selected species, Cussonia paniculata (Eckl. & Zeyh.), C. spicata (Thunb.) and Schefflera umbellifera (Sond.) Baill, = C. umbellifera), in traditional medicine was validated. Rapid propagation protocols for C. paniculata and C. spicata were investigated and ultimately developed for the former species. Cussonia paniculata, C. spicata and C. umbellifera were screened for their medicinal properties, mainly focussing on anti-bacterial, anti-inflammatory and anti-malarial activities. In the anti-bacterial screening, C. spicata bark and root extracts showed activity against selected Gram-positive and Gram-negative bacterial strains at a concentration of 50 mg ml ¯¹ . The highest inhibition was observed with ethanol and ethyl acetate root extracts against Staphylococcus aureus. The other two species did not show anti-bacterial activity. Ethanol and ethyl acetate extracts of all species showed anti-inflammatory activity in the cyclooxygenase assay (COX-1) at a concentration of 8 μg ml ¯¹, These active extracts showed an inhibition percentage that was greater than 50 % against cyclooxygenase. In the anti-malarial screening , bark extracts were screened. C. umbellifera bark extracts exhibited the best inhibition against P. falciparum, a malaria-causing agent in humans. The percentage inhibition of these extracts was up to 100% at a concentration of 200 μg ml ¯¹ . While C. spicata is known to be used to treat malaria, the screening results showed much less activity (less than or equal to 35 %) as compared to C. umbellifera, which is preferably used to treat malaria. The results obtained from screening these three species validated their use in traditional medicine. This means that the people or traditional healers use these species for different treatments by possibly relying on past knowledge about the effects after administering the medicine. Fingerprinting using Thin Layer Chromatography (TLC) was used in an attempt to determine whether there are any chemical differences or similarities between the three species. There were similarities between the plant parts across the species as well as some differences. However, this method cannot be used as an unequivocal test to deduce that compounds that are present in a certain species and not in others are the ones responsible for bringing about a certain biological activity. That can only be achieved by a bioassay-guided isolation of possible compounds. A tissue culture protocol was developed to produce a large -number of plants of C. paniculata. Explants were derived from nodal explants of in vitro germinated seeds and cultured on Murashige and Skoog (MS) (1962) medium supplemented with 3% sucrose, 2.5 mg l ¯¹ BA and solidified with 3 g l ¯¹ Gelrite. These explants produced multiple shoots. The average number of shoots per explant ranged between 1 to 3.5. Multishoots were subcultured on to rooting media and roots were produced on MS with 0.75 mg l ¯¹ IBA and 1 mg l ¯¹ NAA. Callus from zygotic embryos also produced plantlets on MS supplemented with 1.5 mg l ¯¹ 2,4-D and 0.5 mg l ¯¹ BA. Hyperhydricity was encountered in this study. This problem was reversed successfully by transferring the shoots from medium solidified with 3 g l ¯¹ Gelrite to medium solidified with 8 g l ¯¹ agar. Plantlets were successfully acclimatized for planting ex vitro. The percentage of healthy plants after a 35-day acclimatization period was 63 %. C. spicata was not successfully micropropagated from shoot-tip explants. However, a protocol was developed for decontaminating shoot-tips from the mother plants. The plant material was successfully decontaminated with 0.01% HgCl₂ for 15 min. The decontamination percentage was up to 80 %. Browning of the explants was observed and it was successfully treated with soaking the explants in a 15 mg l ¯¹ ascorbic acid solution for 15 min. A high percentage of shoot-tip regeneration (80 %) was observed when they were cultured on MS medium supplemented with 2 mg l ¯¹ BA, 1 mg l ¯¹ IAA and 1 mg l ¯¹ GA₃. However, multishoots were not observed as in C. panicualata. Shoot elongation in vitro was similar to shoot elongation as it occurs in nature. The shoots elongated and a flush of palmitately arranged leaves were produced. Further research is required to investigate a commercially viable protocol for rapid propagation and conservation of the germplasm of Cussonia species. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

The medicinal plant Sutherlandia frutescens (SF) is commonly consumed in South Africa, and is traditionally applied to a range of ailments. Yet its popularity stems from the use of SF as a cancer treatment. This plant contains a range of active compounds including L-canavanine (L-CAV), D-pinitol and gamma (γ)-aminobutyric acid, all of which contribute to the therapeutic properties of SF. It is also endorsed by the South African Ministry of Health as a supplementary treatment for HIV/AIDS. Maize is the staple crop of South Africa, and can be frequently contaminated by the mycotoxin fumonisin B1 (FB1). The mycotoxin is linked to an extensive list of livestock diseases. Although little is known about its role in human disease, FB1 has been epidemiologically linked to oesophageal cancer in South Africa. Both SF and FB1 have been shown to promote apoptosis, and the effect(s) of consuming both in combination is currently unknown. The principle aim of this study was to determine whether SF and FB1 had either synergistic or antagonising effects in combination, by investigating immune cell toxicity Jurkat cells. Apoptotic parameters such as caspase activation, mitochondrial depolarisation, phosphatidylserine (PS) externalisation and ATP quantification were analysed. Levels of caspase activation were highest in cells treated with SF only (caspase-3: 86.79 RLU, no significance compared to other treatments; caspase-8: 40.1 RLU, significance compared to other treatments [p<0.05]; caspase-9: 11.07 RLU, significance compared to FB1 and control treatments [p<0.05]). ATP levels were significantly highest in SF-treated cells compared to other treatments (8.17 RLU, [p<0.05]). Mitochondrial depolarisation was also highest in SF-treated Jurkat cells at 18.5% depolarisation with no significance compared to other treatments, however PS externalisation were significantly lower in SF-treated cells compared with other treatments (3.69% [p<0.05]). Oxidative stress parameters were also investigated, including thiobutyric acid reactive species (TBARS), Glutathione (GSH) and Reactive Nitrogen Species (RNS) assays. TBARS levels were significantly higher in FB1 treated cells (OD 1.95, [p<0.05]) compared to SF and control. Glutathione and RNS levels were also lowest in FB1-treated cells. The data suggests that SF induces apoptosis, characteristic of its nature as an anti-cancer treatment, and FB1 induces oxidative stress, which is characteristic of its carcinogenic properties. Based on this preliminary study, it appears that FB1 and SF both synergises and antagonises the other in combination, yet further investigation is needed into its effects in vivo. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, 2011.

<p>Artemisia Afra, a popular South African traditional herbal medicine is commonly administered as a tea infusion of the leaves. However, clinical trials proving it safety and efficacy are lacking mainly due to the absence of good quality dosage forms and credible placebos for the plant. The objectives of this study were to prepare a standardized preparation of the plant leaves and freeze-dried aqueous extract powder of the leaves, in a tea bag dosage form and to design and prepare credible placebos for these plant materials.</p>

<p>In South Africa, the crude aqueous extract from Hypoxis hemerocallidea is used by AIDS patients to treat opportunistic infections, such as tuberculosis. The rapid emergence of multidrug-resistant tuberculosis, and extreme drug resistant tuberculosis, in recent years, is a major threat to human health. The treatment of TB, nosocomial bacterial infections, and fungal infections is now a clinical challenge, especially in the immuno-compromised individual. There is a dire need for novel antibiotic alternatives with phytotherapies and plant-derived compounds as potentially promising alternatives. The main objective of this study was to investigate the antimycobacterial activity of Hypoxis hemerocallidea, a South African medicinal plant, using Mycobacterium smegmatis.</p>

Thesis (M.A.)--University of Waterloo, 1994. / Includes bibliographical references (p. 131-142).

Thesis (M.A.)--University of Waterloo, 1994. / Includes bibliographical references (p. 131-142).

Thesis (Ph. D.) (Botany)--University of Pretoria, 2002.

Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 132-147). Also available on the World Wide Web.

Thesis (MSc.(Pharmacology)--Faculty of Health Sciences)-University of Pretoria, 2007.

Thesis (M.S.)--The University of North Carolina at Greensboro, 2008. / Directed by Nadja Cech; submitted to the Dept. of Chemistry and Biochemistry. Title from PDF t.p. (viewed Apr. 13, 2010). Includes bibliographical references (p. 62-68).