Pterocarpus erinaceus Poir. (Fabaceae) est une plante médicinale utilisée dans la prise en charge de nombreuses pathologies dont les maladies à composante inflammatoire au Burkina Faso. Les feuilles, le tronc, et les racines sont utilisés comme remède dans le traitement des dermatoses, de l’inflammation, de l’ulcère, du rhumatisme, de la dysenterie, le paludisme, etc. L’objectif de ce travail était de mener des études phytochimiques et pharmacologiques sur des extraits de Pterocarpus erinaceus Poir. (Fabaceae) afin d’évaluer l’innocuité et l’efficacité de cette plante en vue d’obtenir des pré-requis pour le développement d’un phytomédicament. L’étude phytochimique a été réalisée en utilisant des méthodes chromatographiques (CCM, SPE, CC, VLC, MPLC, CLHP) et spectroscopiques (RMN 1D et 2D). Cette étude a permis d’isoler 18 molécules dont 14 identifiées à savoir la friedeline (2 fois), le lupeol, l’épicatechine, la rutine, la lutéoline, la quercétine-3-O-sophoroside, le kaempferol-3-Osophoroside, la quercétine-3-O-β-glucose, le stigmastérol, la friedeline, le 3α-hydroxyfriedelan-2-one, l’α-sophoradiol et le maltol 6-O-apiofuranoside-glucopyranoside. L’étude sur la toxicité aiguë a montré que les décoctés des feuilles (DECFEU), d’écorces de tronc (DECEC), d’écorces de racines (DECRA) et les extraits méthanoliques des feuilles (MeOH K), d’écorces du tronc (MeOH B) sont considérés comme des substances faiblement toxiques selon l’échelle de toxicité de Hodge et Sterner et de l’OMS. Les effets antiinflammatoires, analgésiques et antipyrétiques des extraits issus des écorces de tronc, des feuilles et des racines ont été validés sur des modèles animaux. Les résultats obtenus dans les tests in vitro (antioxydant, tests sur l’inhibition de la production de TNF α et de nitrite cellulaires, de la peroxydation lipidique et de la lipoxygénase) montrent que les extraits manifestent des effets intéressants; plus particulièrement l’extrait méthanolique des écorces du tronc (MeOH B) qui a le meilleur pouvoir antioxydant (ARP = 5 ; TEAC = 0,9) et la forte inhibition sur la peroxydation lipidique (37,25 %) et sur la lipoxygénase (97,69 %). Par contre l’extrait méthanolique des feuilles (MeOH K) a présenté la forte inhibition à la concentration de 50 μg/mL sur la production de TNF α (37,35 % et 30 %) et de NO (95 % et 50%) dans la culture de macrophages activés par LPS et LPS/IFN γ / Pterocarpus erinaceus Poir. (Fabaceae) is a medicinal plant used in the treatment of several diseases including diseases inflammatory component in Burkina Faso. The leaves, stem and roots are used as a drug in the treatment of skin diseases, inflammation, ulcer, rheumatism, dysentery, malaria. The aim of this study was to carry out phytochemical and pharmacological studies on extracts of Pterocarpus erinaceus Poir. (Fabaceae) to evaluate the safety and efficacy of this plant to obtain the data for the development of a drug. Phytochemical study has been performed using chromatographic methods (TLC, SPE, CC, VLC, MPLC, HPLC) and spectroscopic (1D and 2D NMR). This study has been leading to isolated 18 molecules including 14 identified namely friedelin, lupeol, epicatechin, rutin, luteolin, quercetin-3-O-sophorosid, kaempferol-3-O-sophorosid, quercetin-3-O-β-glucose, stigmasterol, 3α-hydroxyfriedelan-2-on, α-sophoradiol, maltol-6-O-apiofuranosideglucopyranoside. The test on acute toxicity showed that the decoction of the leaves (DECFEU), stem (DECEC), roots (DECRA) and methanol extracts of leaves (MeOH K), stem bark (MeOH B) are considered slightly toxic substances according to the toxicity scale of Hodge and Sterner and WHO. The anti-inflammatory, analgesic and antipyretic extracts from the stem bark, leaves and roots have been validated en animal models. The results obtained in vitro test (antioxidant test, tests on the inhibition of the production of cellular TNF α and nitrite, lipid peroxidation and lipoxygénase) showed that the extracts exhibited effects, especially the methanol extract stem bark (MeOH B) which has the best antioxidant power (ARP = 5; TEAC = 9) and the strongest inhibition of lipid peroxidation (37.25 %) and lipoxygénase (97.69 %). However the methanol extract of leaves (MeOH K) presented strong inhibition at a concentration of 50 μg/mL on the production of TNF α (37.35 % and 30 %) and NO (95 % and 50 %) in the macrophages cultures active by LPS and LPS/INF-γ

Thesis (Ph.D. (Biochemistry)) --University of Limpopo, 2009 / Refer to document / National Research Foundation (NRF) and University of Limpopo

For centuries Traditional Health Practitioners (THPs) used their indigenous knowledge (IK) in conserving medicinal plants and environments to maintain sustainability. With the rapid environmental, social, economic and political changes occurring in many areas inhabited by rural people exist the danger that the loss of biodiversity from habitat destruction and unsustainable harvesting practices will result in some species becoming extinct. The main aim of the study was to determine the natural habitat of extinction-prone traditional medicinal plants combining the insight of THPs with an ultimate goal of guiding research for the conservation, propagation and cultivation of traditional medicinal plants. Despite problems, opportunities and challenges expressed and identified by THPs, the analysis of data from interview schedule and personal observations, show that the THPs' practices are shaped by historical processes and local cultural values, social norms and their management strategies that are influenced by a broad range of factors. / Agriculture, Animal Health and Human Ecology / M.A. (Human Ecology)

Thesis (Ph.D. (Biochemistry)) --University of Limpopo, 2009 / Commelina benghalensis Linn is used in traditional medicine in several Asian and African countries for the treatment of various ailments such as stomach irritations, burns, sore throat and feet, diarrhoea and as an anti-inflammatory agent. Recently, our laboratory showed that the crude methanolic extract of Commelina benghalensis L (CMECB) exhibits growth inhibitory and proapoptotic effects in Jurkat T and Wil-2 NS cancer cell lines. In this study, the precise molecular mechanism(s) associated with CMECB-induced growth inhibitory and apoptosis inducing effects in Jurkat T and Wil-2 NS cell lines were investigated. This was achieved by investigating the effects of the extract on the cell division cycle distribution profile as well as its effects on various cell division cycle and apoptosis regulatory genes. Ground stems of C. benghalensis L were extracted with absolute methanol to obtain a crude extract. To assess the effect of CMECB on cancer cell growth, experimental cell cultures were exposed to various concentrations (0 to 600 μg/ml) of CMECB for up to 72 hours. The results demonstrated a significant reduction in cell viability and inhibition of proliferation of experimental cell cultures as determined by the trypan blue dye exclusion assay and the Coulter counter method, respectively. Analysis of nuclear morphological changes in cells stained with Hoechst 33258 confirmed apoptosis as the mode of cell death that is associated with the growth inhibitory effects of CMECB in both the Jurkat T and Wil-2 NS cell lines. This assertion was based on the observed presence of nuclear morphological changes such as chromatin condensation and fragmentation and apoptotic bodies in cells exposed to CMECB. In order to get an insight on the pro-apoptotic mechanisms of CMECB, Western blot xxi and quantitative real-time PCR (qrt-PCR) were used to investigate the expression profiles of various apoptosis and cell division cycle regulatory genes. Qrt-PCR results showed a lack of a clear up- and/or down-regulatory effects of CMECB on the mRNA expression levels of bax and bcl-2 in both Jurkat T and Wil-2 NS cells. Western blot analyses demonstrated that CMECB induced apoptosis by facilitating Bax protein translocation from the cytosol to the mitochondria in both Jurkat T and Wil-2 NS cells. In addition, CMECB down-regulated Bcl-2 protein expression which, as a result, led to the shift in the Bax/Bcl-2 protein ratio at certain time points and concentration in both Jurkat T and Wil-2 NS cells. The modulation of the Bcl-2 family members led to mitochondrial cytochrome c release into the cytosol and activation of caspases-9 and -3; this was also confirmed by caspase activity assays and eventual degradation of PARP. Furthermore, CMECB induced Jurkat T and Wil-2 NS cell division cycle arrest at the G2/M phase as determined by flow cytometric analysis. Western blot analyses of G2/M phase regulatory proteins demonstrated that the CMECB-induced cell division cycle arrest was associated with the downregulation of cyclin B1 and Cdc2 protein expression levels. Western blot analyses results further revealed that the arrest of Wil-2 NS cells at the G2/M phase was independent of p21 protein activity. However, Jurkat T cell division cycle arrest was found to be mediated, in part, by p21. Quantitative real-time PCR results did not show a clear trend in terms of the down- or up-regulatory effects of the extracts on the G2/M phase regulatory genes. The CMECBinduced apoptosis and G2/M arrest was found to occur in a p53-independent xxii manner due to the lack and down-regulation of p53 protein levels in both Jurkat T and Wil-2 NS cells, respectively. In conclusion, CMECB induces its anticancer activity by inducing G2/M phase arrest and mitochondrial-mediated apoptosis independent of p53 protein activity. Although the study did not perform in vivo experiments to ascertain the efficacy of extracts of CMECB against specific tumour types in animal models, the present findings somehow validate the traditional use of C. benghalensis L as an anticancer agent. A more definitive study needs to be done to ascertain this assertion. / National Research Foundation and the University of Limpopo research office

Thesis (M.Sc. (Botany)) -- University of Limpopo, 2013 / Traditional medicine plays a major role in the primary health care of many people residing in rural areas. People in these areas still consult traditional healers who utilise plants as medicine. Medicinal plants have come under increasing pressure due to a number of factors, which have resulted in the decline of certain species, extinction in others, and a general decrease in biodiversity of high use areas of South Africa, Blouberg Mountain included. To date there has been a lack of information on how traditional healers utilise the Blouberg Mountain with respect to amounts and species removed, or where the most important collecting sites are located. Thus, no conservation strategy exists for the Blouberg Mountain to ensure sustainable management of its natural resources. Furthermore, there is a perception amongst elders of this area that, as with indigenous knowledge around the world, the knowledge centered around Blouberg’s medicinal plants is declining, and little formal documentation of that knowledge has taken place. Consequently, this study investigated aspects related to medicinal plant use such as collection, patterns of collection, legislation, storage and packaging of medicinal plants by traditional healers around Blouberg Mountain. These were documented via a semi-structured questionnaire and a data collection sheet. Furthermore, traditional harvesting methods employed by traditional healers, and in situ conservation issues related to species removal from the mountain were investigated. Data was collected between September 2010 and September 2011. Sixteen villages in close proximity to the mountain, and 32 healers (two per village) were selected. In addition 16 consulting rooms were sampled (one per village) in order to gather information on the number of species collected from the mountain and stored in the consulting rooms. The 16 most used (indicated by village traditional healers) collection tracks, (one per village surrounding Blouberg Mountain), were travelled with traditional healers to record botanical and vernacular names of the medicinal plants, vegetation type, habitat, parts used, harvesting method, replacement value of plant species and perceived rarity of collected material. A Garmin GPS was used to record waypoints for the beginning and end of each track. Co-ordinates were logged automatically every 10 m. A map using Quantum GIS software to capture the position of the healers’ collection tracks, overlaid with topographical and vegetation information, and protected area information of the Blouberg Mountain, was generated. Geographic Information System software was used to geo-process the collection tracks of the healers with respect to where medicinal plants were collected relative to the various vegetation types. This gave information on vegetation types important to healers. The majority of traditional healers were females. Most of them had no formal education, with only a minority reaching secondary school. Due to their low level of literacy they tended to shy away from sources of written information, with the result that none of the questioned healers had any knowledge of the various national or provincial environmental legislations. The majority of them see between 15 and 20 patients per month. Most of the healers had more than 30 years of experience in traditional healing. The study found 64 plant species commonly used for medicinal purposes. Most of them were harvested for their roots and bark. According to the healers, Boophane disticha and Hypoxis hemerocallidea are declining in Blouberg Mountain, with Warburgia salutaris, endangered in South Africa, not perceived as rare or declining. However, a number of plant species recorded in the Red Data List as of least concern, or not threatened, are seen as rare by the healers. These include Clivia caulescens, Erythrina lysistemon, Lannea schweinfurthii and Maerua juncea. No exotic species were documented from the surveyed tracks. However, two naturalised exotics were collected from the mountain, namely Cassytha filiformis and Corchorus tridens. Cocculus hirsutus, a naturalised exotic and Abrus precatorius, an exotic species were found in one of the consulting rooms. Dichrostachys cinerea, Philenoptera violacea and Tarchonanthus camphoratus, which are indicators of bush encroachment, were identified on selected tracks. Tracks on which indicators of bush encroachment are present should be investigated more thoroughly to ascertain the extent and severity of such a threat. vii Investigations into healers’ collection tracks showed that the Soutpansberg Mountain Bushveld vegetation type is the most heavily utilised of the five vegetation types around Blouberg Mountain. This vegetation type is vulnerable to human population densities as most species were collected from it, therefore it should be conserved and managed if possible as it is targeted for plant species of medicinal value. The most travelled tracks were found in the Catha-Faurea Wooded Grassland community. Solutions to the problems of over harvesting of medicinal plants require local innovations and the full participation of traditional healers in resource management initiatives. The development of medicinal plant nurseries together with propagation of key species will be a crucial management tool, as this will reduce over harvesting of natural resources from the wild. In conclusion, it was found that although most species utilised around Blouberg Mountain are abundant and not threatened, healers are nevertheless concerned about dwindling medicinal plant supplies. They would welcome conservation initiatives and the use of GIS maps would be useful in prioritising conservation areas.

Le platane est un arbre de la famille des Platanaceae très commun en ville en particulier en Europe et dans toutes les zones tempérées. Les espèces du genre Platanus et plus particulièrement l’espèce Platanus orientalis, très répandue en Grèce, sont sévèrement attaquées par des agents phytopathogènes provoquant le chancre coloré du platane, l’anthracnose ou l’oïdium. En revanche, Platanus acerifolia, un hybride obtenu entre P. occidentalis and P. orientalis, très commun en France, se montre plus résistant vis-à-vis de ces pathogènes. L’étude par HPLC d’extraits de deux espèces de Platanaceae européennes P. acerifolia et P. orientalis a montré des différences selon le solvant d’extraction. L’extrait dichlorométhanique de P. acerifolia s’est montré plus riche en composés que l’espèce P. orientalis. Par contre, les chromatogrammes obtenus à partir des extraits méthanoliques sont très similaires et dominés par les deux composés majoritaires (tiliroside et platanoside). Des techniques préparatives comme la chromatographie de partage centrifuge (CPC), la moyenne pression (MPLC), la chromatographie sur colonne de Sephadex ou sur résine XAD-7 ont été utilisées afin d’isoler les différents constituants majoritaires et d’identifier les composés qui diffèrent d’une espèce à l’autre. L’élucidation structurale est réalisée grâce à des techniques telles que HR-EIS-MS et RMN 1D & 2D. L’étude de l’extrait dichlorométhanique nous a permis de compléter la connaissance phytochimique de ces deux plantes européennes et a conduit à l’isolement et à la détermination structurale de 38 molécules dont 7 composés nouveaux (1 coumarine, 3 flavonols prenylés, 2 dihydrochalcones, un terpénoïde. Par ailleurs, l’extrait méthanolique a conduit d’une part à l’isolement du tiliroside et du platanoside majoritaires et d’autre part à l’isolement de composés minoritaires, trente-trois autres molécules dont 5 nouveaux composés (1 flavonol glucosylé, 3 coumarines, 1 dihydrochalcone). Enfin, l’évaluation biologique des composés isolés in vitro ou in vivo a été réalisée sur différentes cibles : activités antifongiques, anti-âge, antioestrogéniques. Les activités cytotoxiques sur les cellules de cancer du sein MCF-7 et sur les cellules de cancer de l’endomètre (ISHIKAWA). / Platanus is a small genus of trees belonging to Platanaceae family, very common in Europe and temperate zones. Platanus species, and especially Platanus orientalis (Oriental plane), wide-spread in Greece are known to be severely attacked by phytopathogens such as Ceratocystis fimbriata f. sp. platani for canker stain, Apiognomonia veneta for anthracnose and Microsphaera platini for powdery mildew. However Platanus acerifolia (London plane), a hybrid between the P. occidentalis and P. orientalis, which is very common in France, have been found to be resistant to these pathogenic fungi. The HPLC profile of the dichloromethane extracts of the two species P. orientalis and P. acerifolia revealed a qualititative difference whereas, the methanol extracts were found to be similar with two predominant phenolic constituents (tiliroside and platanoside) present in both species. Further isolation and purification of their secondary metabolites were performed using various chromatographic techniques (CPC, MPLC, CC, XAD-7, Sephadex LH20, prep-TLC) and their identification was performed by HRMS and NMR (1 & 2D) spectroscopy. The studies of dichloromethane extract allowed us to deal with phytochemical knowledge of these two European plants in depth and led to isolation and structural elucidation of 38 compounds including 7 news constituents (1 coumarin, 3 flavonols, 2 dihydrochalcones and 1 terpenoid). Moreover, the methanol extract led to the isolation of their major constituents (tiliroside and platanoside) in one step. Furthermore, 33 minors compounds were isolated including 5 news compounds (one flavonol glycoside 3 coumarins and 1 dihydrochalcone). In addition, the isolated compounds have been subjected to in vitro or in vivo evaluation on different targets: antifungal, anti-ageing, anti-oestrogenic properties. Finally, the cytotoxic activity was studied on breast cancer cells (MCF-7) and endometrial cancer (Ishikawa).

Pour la première fois, l’étude de la flore fongique endophytique de cinq plantes médicinales soudanaises : Calotropis procera (Ait.), Catharanthus roseus (L.), Euphorbia prostrata (Ait.), Trigonella foenum-graecum (L.), and Vernonia amygdalina (Del.) a été réalisée. Un total de 23 souches de champignons endophytes ont été isolées à partir des plantes après la stérilisation de surface puis les différentes analyses biologiques ont été effectuées. Les extraits bruts d’acétate d’éthyle de 21 endophytes ainsi que de leurs plantes hôtes ont été évalués pour leur teneur en phénols totaux et leur activité antioxydante en utilisant respectivement la méthode colorimértrique Folin-Ciocalteu et le piégeage des radicaux libres par la méthode 1,1,-diphényl-2-picrylhydrazil (DPPH) in vitro. Une évaluation générale de la cytotoxicité de 16 endophytes sélectionnés ainsi que de leurs plantes hôtes a été réalisée selon le test MTT sur trois types de cellules cancéreuses : carcinome du sein humain (MCF7), adénocarcinome du côlon (HT29 et HCT116). Ces extraits ont été aussi testés, selon la méthode de dilution en bouillon, sur deux souches bactériennes représentatives, Escherichia coli et la souche résistante à la méthicilline de Staphylococcus aureus. La teneur en phénols totaux (89,9 ±7,1 mg Equivalent d’Acide Gallique EAG/g) ainsi que l’activité antioxydante (IC50: 18±0,1 µg/mL) les plus élevées ont été observées pour l’endophyte, Aspergillus terreus 2 isolé à partir des graines de T. foenum-graecum. Byssochlamys spectabilis a montré l’activité cytotoxique la plus importante (1,51 ± 0,2 µg/mL), suivi par Cladosporium cladosporioides 2 (10,5 ± 1,5 µg/mL), puis par Alternaria sp. (13,5 ± 1,8 µg/mL). Seules six souches ont montré une activité contre S. aureus avec des valeurs de MIC qui se situent entre 0,125 et 2 mg/mL dont: Alternaria alternata (0,125 mg/mL), Alternaria sp. (0,250 mg/mL), Byssochlamys spectabilis (0,5 mg/mL). 10 composés purs (0,3 à 40 mg) ont été isolés à partir des extraits bruts d’acétate d’éthyle de Curvularia papendorfii. Le nouveau composé pur (AFB) 3,7,11,15-Tetrahydroxy-18-hydroxymethyl-14,16,20,22,24-pentamethyl-hexacosa-4E,8E,12E,16,18-pentaenoic acid (acide Khartomique) a montré une activité antibactérienne modérée contre S. aureus avec une CIM de 62,5 µg/mL et une faible activité cytotoxique sur les cellules MCF7 avec une IC50 > 100 µM. Le composé pur AF1 a montré une activité cytotoxique modérée sur les cellules HT29 avec une IC50 de 29,78 µM et une très faible activité antibactérienne contre S. aureus. Ces deux composés ne présentent pas d’activité antioxydante. / This study investigated, for the first time, the endophytic fungi flora of five Sudanese medicinal plants: Calotropis procera (Ait.), Catharanthus roseus (L.), Euphorbia prostrata (Ait.), Trigonella foenum-graecum (L.) and Vernonia amygdalina (Del.). A total of 23 endophytic fungal strains were isolated from the plants after surface disinfection and different biological tests were performed. Total phenolic content (TPC) and total antioxidant activity of ethyl acetate crude extracts of 21 endophytes and their host plants were estimated using respectively the Folin-Ciocalteu colorimetric method and 1,1,-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging in vitro method. General evaluation of the cytotoxicity of 16 selected endophytes and their host plants was performed by the MTT assay using cancer cells type: Human breast carcinoma (MCF7) and Colon adenocarcinoma (HT29 and HCT116). Preliminary antibacterial screening was done for the 16 endophytes. These extracts were also tested against two representative bacterial strains, Escherichia coli and methicillin-resistant Staphylococcus aureus, by broth dilution tests. The endophyte, Aspergillus terreus 1 from T. foenum-graecum seeds had the highest TPC in term of Gallic Acid Equivalent (89.9 ± 7.1 mg GAE/g) and antioxidant activity (IC50: 18±0.1µg/mL). Byssochlamys spectabilis showed strong cytotoxicity (1.51 ± 0.2 µg/mL) followed by Cladosporium cladosporioides 2 (10.5 ± 1.5 µg/mL), then Alternaria sp. (13.5 ± 1.8 µg/mL). Only six strains showed activity against methicillin-resistant S. aureus with MIC values ranging between 0.125-2 mg/mL, Alternaria alternata (0.125 mg/mL) Alternaria sp. (0.250 mg/mL) and Byssochlamys spectabilis values (0.5 mg/mL). Ten pure compounds (0.3 to 40 mg) were isolated from ethyl acetate crude extract of Curvularia papendorfii .The new pure compound (AFB) 3,7,11,15-Tetrahydroxy-18-hydroxymethyl-14,16,20,22,24-pentamethyl-hexacosa-4E,8E,12E,16,18-pentaenoic acid (Khartoumic acid) revealed moderate antibacterial activity against S. aureus with MIC value 62.5 µg/mL and weak cytotoxicity with a IC50 > 100 µM against MCF7 cells. The pure compound AF1 showed moderate cytotoxic activity with IC50 value of 29.78 µM against HT29 and weak antibacterial activity with MIC 250 µg/mL against S. aureus. Both compounds displayed no antioxidant activity.

PhD (AGR) (Animal Science) / Department of Animal Science / Horticultural by-products such as seed and nut oil residues have the potential to replace conventional protein and energy sources in diets for ruminants. The objective of the study was to evaluate the nutritive value of Macadamia oil cake and Baobab seed cake as nutrient supplements for feedlot animals. Several experiments were carried-out to evaluate the nutritive value of Macadamia oil cake and Baobab seed cake as feed for ruminants. The nutrient composition of the cakes were determined using both proximate and modern methods of analysis of feeds and a t-test was used to compare the means of Macadamia oil cake and Baobab seed cake. The in sacco technique was used to determine the rumen degradability parameters of dry matter, crude protein and Amino acids of the cakes. This experiment was conducted using a completely randomized design. A three step-in vitro technique was used to conduct a post ruminal digestibility trial and the study was arranged in a completely randomized design. An apparent digestibility trial was conducted using metabolism cages and fecal bags to avoid the mixing of urine and faeces and the experiment was carried out as a completely randomized design arranged in a 2 x 2 factorial. A growth trial was conducted using a completely randomized block design arranged in a 2x2 factorial with two protein supplements and two inclusion levels as factors and blocked by sex of the lambs. The two cakes had similar (P>0.05) dry matter, fat, hemicellulose and gross energy contents. Baobab seed cake had significantly (P<0.05) higher ash, crude protein, acid detergent lignin and nitrogen free extract than macadamia oil cake. Macadamia oil cake had significantly (P<0.05) higher crude fiber, acid detergent fiber, neutral detergent fiber and cellulose concentrations. Baobab seed cake had significantly (P<0.05) higher calcium, magnesium, potassium, phosphorus (macroelements), zinc, and copper than macadamia oil cake. Macadamia oil cake was significantly (P<0.05) higher in manganese and iron contents than Baobab seed cake. Sodium content was not significantly (P>0.05) different between the two cakes. Baobab seed cake had more (Tryptophan, Cysteine, Arginine, Aspartic acid, Glutamic acid, Valine, Phenylalanine, Isoleucine, Leucine) Amino acids which were significantly (P<0.05) higher in quantity than macadamia oil cake with the two cakes having similar (P>0.05) remaining Amino acids contents. Generally Macadamia oil cake had more (P<0.05) saturated and mono-unsaturated fatty acids than Baobab seed cake whereas Baobab seed cake had more (P<0.05) poly-unsaturated fatty acids. v The in sacco rumen degradability characteristics of baobab seed cake and macadamia oil cake were estimated for dry matter and crude protein of the cakes. Macadamia oil cake had significantly (P<0.01) higher a value for dry matter than boabab seed cake. Baoaba seed cake had significantly (P<0.01) higher a value for crude protein than macadamia oil cake. the b, c, and a+b values for dry matter of both Baobab seed cake and Macadamia oil cake were not significantly (P>0.05) different form each other. However, the potential degradability (a+b) value for crude protein of baobab seed cake was significantly (P<0.01) higher than that of macadamia oil cake. The b and c constants of the two cakes for crude protein were not significantly (P>0.05) different from each other. The ED (Effective degradability) values calculated at three outflow rates (0.02, 0.05, 0.08) were estimated for dry matter and crude protein of Baobab seed cake and macadamia oil cake. The ED of the two cakes calculated at 0.02 outflow rate did not significantly (P>0.05) differ from each other. However, baobab seed cake had significantly (P<0.05) higher ED value at outflow rate of 0.05 whereas macadamia oil cake had significantly (P<0.05) higher ED value calculated at outflow rate of 0.08. The ED values of baobab seed cake for crude protein calculated at the three outflow rate were significantly (P<0.01) higher than those of macadamia oil cake. The two cakes did not significantly (P>0.05) differ in dry matter ruminal degradability but baobab seed cake had significantly (P<0.05) higher ruminal crude protein disappearance from 16 to 72 hours of incubation than macadamia oil cake. The in situ Amino acid degradation was determined on 0, 12, 16, 24, and 48 hour of ruminal incubation of the cakes’ samples and generally they were significant (P<0.05) differences for both cakes according to different incubation periods. The 3-step in vitro digestibility trial revealed that baobab seed cake had significantly (P<0.05) higher dry matter, crude protein and Amino acids digestibility values than macadamia oil cake. Apparent digestibility study revealed that nutrient intake, faecal and urine outputs, and digestibility of nutrients were not significantly (P>0.05) different between baobab seed cake and macadamia oil cake. However, lambs on 10% macadamia cake having retained significantly (P<0.05) more nitrogen than the lambs on 15% macadamia oil cake, 10% and 15% baobab seed cakes diets. However, the inclusion of either baobab seed cake or macadamia oil cake at 10% or 15% in the diets of lambs did not significantly (P>0.05) affect the DOMR, microbial protein yield and purine derivates output. For the growth trial the lambs were offered four diets formulated to contain 10% MOC (control), 15% MOC, 10 BSC and 15% BSC. The inclusion of 15% MOC and 10% BSC in the diets of lambs did not significantly (P>0.05) affect their final body weight, total weight gain, average daily feed intake, average daily weight gain, warm and cold carcass masses between these two vi groups. The inclusion of 10% MOC and 15% BSC in the diets of lambs did not significantly affect average daily feed intake and animal performance between these two groups. However, lambs on 10% MOC and 15% BSC had significantly (P<0.05) higher average daily feed intake and animal performance compared to lambs on 15% MOC diet. The feed conversion efficiency and of the lambs in the four diets were not significantly (P>0.05) different. The dressing percentage, carcass length, neck weight, fat thickness, body weight thickness and rib eye area of the carcasses of lambs in this trial did not differ significantly (P>0.05) except for spleen and skin with lambs on 10% BSC diets having the least skin weight and lambs on 10% MOC diet having heaver spleens. Generally BSC had higher (P<0.05) nutrient content than MOC. BSC and MOC were highly degradable in the rumen whereas BSC was higly digestible post-ruminally compared to MOC. The diets of fattening lambs formulated to include 10% or 15% of BSC or MOC as protein supplements did not affect the apparent digestibility of the diets. Macadamia oil cake can be incomporated in the diet of finishing lambs as a protein supplement at 10% inclusion level without compromising the growth and carcass characteristics of the lambs. Baobab seed cake as a protein supplement can be included in the diet of finishing lambs at up to 15% inclusion level without deleteriously compromising on the growth and carcass characteristics of the animals. ______________________________________ / NRF

Abstract in English / The number of studies focused on the digital preservation of indigenous knowledge has been growing steadily over the years. Despite the growth in this area of research, there is still a lack of information technology tools that preserve and disseminate indigenous knowledge. Indigenous knowledge has been highlighted as an area that can advance sustainable development, and its preservation is therefore of the utmost importance. Indigenous knowledge is mostly present within older generations, and if it is not preserved, this knowledge will die with its custodians. African communities rely heavily on indigenous medicine. A digital platform needs to be explored that can preserve practices relating to these medicines for future generations. Since indigenous knowledge is dynamic and is constantly evolving, there is a need to explore a digital tool that can highlight this dynamic nature. Current methods of preserving indigenous knowledge of medicinal plants were found to be less than effective and marred by constraints such as space and time. The main objective of this study was therefore to develop a model that could be used to guide the design of a new e-learning system aimed at facilitating the preservation of indigenous knowledge of Namibia’s medicinal plants. In this study, e-learning technology was used to determine the requirements for presenting indigenous knowledge of Namibia’s medicinal plants in such a way as to ensure that individuals can internalise and preserve this knowledge. An interpretivist qualitative approach was followed. Data was collected by conducting a literature review and carrying out a survey. A prototype e-learning system was developed and evaluated based on the collected data. It was found that preserving indigenous knowledge of medicinal plants through e-learning would require, among other things, engagement with the relevant knowledge custodians, leveraging multimedia, and offering content in indigenous languages. / School of Computing / M.Sc. (Computing)

The anti-inflammatory properties of four medicinal plants were investigated. These plant extracts were subjected to screening for their possible effects as antioxidative, analgesic, and anti-inflammatory agents. In the antioxidant activity, the Plantago lancelota extracts resulted in an IC50 value of 0.4 mg/mL compared to the positive control quecertin with IC50 0.04 mg/mL Plantago lanceolata inhibited COX-2 activity with IC50 values of 0.41 mg/mL. However, the COX-1 inhibition indicated an IC50 of 68.99 mg/mL. The lipoxygenase assay indicated that Plantago lanceolata was the most active plant species with an IC50 value of 4.86 mg/mL compared to the positive control (quecertin) with an IC50<2mg/mL. The nitric oxide assay of the plant extracts indicates a dose-dependent activity of our plant extracts. Likewise the cell viability result indicated a good activity at dose 100 mg/mL. / Life and Consumer Sciences / M. Sc. (Life Sciences)