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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Evaluation of the effect of Pelargonium reniforme Curtis extract on alcohol induced liver damage in Nkonkobe Municipality Eastern Cape Province South Africa

Adewusi, Emmanuel Adekanmi January 2009 (has links)
Alcohol abuse is a very common practice (just like in many other parts of the world) in Nkonkobe Municipality, Eastern Cape Province, South Africa. This is associated with liver disease. An ethnobotanical survey of plants used for the treatment of alcohol-induced liver damage in Nkonkobe Municipality was conducted. During the survey and also from information gathered in the literature, Pelargonium reniforme Curtis, was prominently mentioned, among other plants, as the species used generally for the treatment of alcohol-induced liver damage. This project was designed to evaluate the effects of the plant on alcohol-induced liver damage, including its antioxidant and antimicrobial properties. It also involves safety evaluation studies to determine if the plant is safe for consumption. Studies using rats of the Wistar strain were carried out to determine the protective and curative effects of P. reniforme on alcohol-induced liver damage. Results obtained showed that the plant extract can protect the liver cells as well as enhance recovery from tissue damage. The plant also showed good antimicrobial and antioxidant activity and this further validates its use in the treatment of liver diseases. Safety evaluation studies of the extract were carried out by investigating the effects of the oral administration on some haematological and biochemical parameters in male Wistar rats. The results obtained from the study suggest that the plant extract is not toxic at the doses used and is therefore safe for medicinal uses. The results of the various bioassays carried out in this project have justified the traditional uses of P. reniforme for the treatment of alcohol-induced liver damage.
102

The acceptability of medicinal plant gardens: Healers' perspective from Nkomanzi East Region

Kelatwang, Teresa Sebueng 01 August 2005 (has links)
The use and trade in medicinal plant products in South Africa is a cultivating sector of rural development. In order to conserve these plants and develop sustainable production, policies to promote domestication have been adopted. However, users view cultivated plants with scepticism. The key for policy makers is to understand how users respond to scarcity of species and whether domestication can be a solution. The main purpose of the study is to give an overview of variables that influence the rate of adoption of medicinal plant gardens. The last discussion will investigate whether domestication of species is an appropriate solution to conservation, or whether the intervention should be promoted as a local economic development option. The research took the form of a case study approach focusing on a specific area, with participatory and qualitative phases providing the basis for a semi-structured interview schedule, designed to assess the healer's acceptability of medicinal plant gardens, their comparative perception of cultivated and collected plants in their natural habitat/environment, and constraints in the establishment of medicinal plant gardens. Results indicated that:<li> The type of healer influences acceptability of medicinal plant gardens; •Healers use medicinal plant gardens to supply urban demand and provide income; • Healer and client perceptions of medicinal plant potency influence acceptability of cultivated plants; •Type of healer influences the environment in which species are collected. • Ancestral belief system forms an integral component of healers behavioural pattern.</li> The study concludes that:<li> Local scarcity of medicinal plants alone does not stimulate demand for nurseries; • Rituals associated with some treatments influence collection, storage and cultivation patterns; • Policy makers also need to promote domestication for commercial production and to investigate alternatives for propagating the population of some plant species in their natural habitat/environment to cater for specific needs of healers and • Interview responses, although useful, cannot always be taken at face value<//i>. / Dissertation (M Inst Agrar ( Agricultural Extension))--University of Pretoria, 2005. / Agricultural Economics, Extension and Rural Development / unrestricted
103

The effects of debarking and seasonal variations on physical structure; phenolic content and biological activities of Sclerocarya Birrea in the Nylsvley Nature Reserve

Nndwammbi, Matodzi 05 1900 (has links)
MSc (Botany) / Department of Botany / See the attached abstract below
104

Reproductive biology towards the conservation of securidaca longepedunculata fresen in theNylsvley Nature Reserve, Limpopo Province, South Africa

Tiawoun, Makuete Andre Patrick 15 February 2016 (has links)
MSc (Botany)
105

The antioxidant, cytotoxicity and antimicrobial activities of medicinal plants used for male sexual healing in Venda, Limpopo Province

Nelwamondo, Munyadziwa Rosette January 2022 (has links)
Thesis (M. Sc. (Microbiology)) -- University of Limpopo, 2022 / Sexually transmitted infections represent one of the main health problems related to reproductive and sexual function, constituting one of the main causes of infertility. Plants have been employed traditionally in treating diseases for centuries. Elephantorrhiza burkei, Securidaca longepedunculata and Wrightia natalensis medicinal plants were selected for this study based on their use in traditional medicine to treat sexual health problems in Limpopo Province. The aim of the study was to determine antimicrobial and antioxidant properties of the selected plants. Different extraction procedures coupled with solvents of varying polarities were used in the extraction of the plant materials. Possible microbial contaminants were identified using the VITEK 2 instrument. Qualitative phytochemical analysis was determined using standard chemical tests and Thin-Layer Chromatography. Total polyphenol content was quantified calorimetrically. Antioxidant activity was quantified using 2, 2-diphenyl- 1-picrylhydrazyl (DPPH) and ferric reducing power assays. In vitro antimicrobial activities were determined using a broth micro-dilution assay and bioautography. Combinational effects of the addition of multiple plant species on antimicrobial activity were investigated for additive, synergistic and antagonistic interactions. The plant species phytochemical profile contained polyphenols that are known to have antimicrobial effects against two Gram-positive bacteria, Staphylococcus aureus (ATCC 29213) and Enterococcus faecalis (ATCC 29212), a Gram-negative bacterium, as well as the fungus, Candida albicans (ATCC 10231). Elephantorrhiza burkei exhibited high antioxidant activity and antimicrobial activity against the test pathogens, although most of the interactions were antagonistic and indifferent. Toxicity was found in the herbal treatment and acute toxicity was found in the selected plants. Based on the good correlations which were found in E. burkei, it was selected for bioactivity guided by an isolation of antibacterial compounds. Elephantorrhiza burkei was not successfully isolated, but the fraction collected showed exceptional biological activity that validates its usage against disease-causing pathogens related to sexually transmitted infections, which compromises male sexual health. This study suggests that the evaluated plants are potential sources of novel anti-infective agents. Further in vivo and in vitro studies are recommended for all the plants, respectively. / University of Limpopo and CSIR
106

Antimycobacterial activity of synthetic compounds isolated from South African medicinal plants against mycobacterium tuberculosis

Ledwaba, Elizabeth Ramadimetsa 11 1900 (has links)
M. Tech. (Department of Health Sciences, Faculty of Applied and Computer Sciences), Vaal University of Technology. / Tuberculosis (TB) remains one of the most difficult infectious diseases to control in the world today. The disease spreads easily in overcrowded, badly ventilated places and among people who are undernourished. Trends in the incidence of TB together with the development of multi-drug (MDR-TB) and extensively drug resistant (XDR-TB) strains of TB raises the need to intensify the search for more efficient drugs to combat this disease. Herbal remedies used in traditional medicine provide an interesting and largely unexplored source for the discovery of potentially new drugs for infections such as TB. The aim of the study was to evaluate the in vitro antimycobacterial activity of synthesized compounds from medicinal plants against Mycobacterium tuberculosis (M. tuberculosis). About 40 synthesized compounds isolated from South African medicinal plants were screened against H37RV using microplate alamar blue assay (MABA). Identified active compounds were screened against resistant strains of M. tuberculosis (MDR, XDR and pre-XDR) and sensitive clinical isolates of TB. Cytotoxicity and synergistic drug combination studies were done on active compounds to validate their toxicity and synergy levels. Cytotoxicity was done by sulforhodamine assay (SRB) against the C2C12 cell line. Only six compounds showed activity against M. tuberculosis with minimum inhibitory concentration (MIC) below 10μg/ml. The results obtained indicated that the cytotoxicity effects of the three compounds on C2C12 cells demonstrated marginal toxicity except for MVB 282/61215 which showed a high toxicity at the lowest concentration of 0.156μg/ml with over 100% viable cells at the highest concentration (5μg/ml). MVB 282/61271 had the highest percentage cell viability (65%) at the lowest concentration. Only two compounds had a higher potency evoking a bigger response at low concentrations with treated cells still viable after 3 days of incubation with the compound which was comparable with the treatment of isoniazid (INH). Synergistic activity of the six compounds was less in INH combination as compared to the rifampicin’s (RIF) combination. The results demonstrated that the synergistic interaction between the compounds and RIF could the antituberculosis acitivity. In conclusion the synergistic effects with RIF translate to lower dosing requirements of the compounds and the potential to combat multidrug resistant TB. In deed there is no doubt that natural products, with their range of interesting chemical structures and powerful antimycobacterial effects are certain to remain important participants in the development of new generations of antimycobacterial drugs.
107

A scientific investigation of the immunomodulatory properties of an indigenous plant, Sutherlandia frutescens

Gonyela, Odwa 01 1900 (has links)
Traditional medicines prepared from Sutherlandia frutescens are used to manage diseases including HIV and cancer. This study aimed at isolating and identifying biologically active compounds isolated from S. frutescens. Sutherlandia frutescens plants were collected in Petrusburg and Paarl. Powdered plant material was extracted using ethanol or water and their metabolite composition was compared using UPLC-MS. A novel cycloartane, an acetylated variant of this compound as well as a Sutherlandioside B triterpenoid was isolated and characterised using chromatographic and analytical techniques such as NMR and UPLC-MS. Preliminary biological studies were conducted to assess the activity of plant extracts on cell toxicity, herpes virus replication and cytokine expression. The results of this study suggest that aqueous extracts from S. frutescens do not appear to be cytotoxic or show anti-herpetic activity, but may activate the immune system by increasing expression of IL-6, IL-10 and TNFα. Further research should be conducted to confirm and optimise these results. / Life and Consumer Sciences / M. Sc. (Life Science)
108

The medicinal properties of ipomoea oblongata E.Mey. ex Choisy

Polori, Ketlareng Liza January 2014 (has links)
Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, 2014. / Traditional medicine has been known by mankind since ancient times as a healthcare system. All cultures have used herbs throughout history and it was an integral part of the development of modern civilization. Primitive man observed and appreciated the great diversity of plants available to him. Plants provided food, clothes, shelter and medicine and still play a vital role in rural villages of South Africa. The medicinal uses of plants and animals have been developed through trial and error. Herbal plants produce and contain a wide variety of chemical substances that act upon the body’s immune system. The medicinal properties of Ipomoea oblongata (E.Mey.ex Choisy) in this study was to determine the phytochemical content, antioxidant, anti-cancer and anti-diabetic properties of I. oblongata (Mothokho), a medicinal plant used by traditional medical practitioners of Thaba-Nchu in the Free State. The study was carried out in order to validate the ethnomedicinal claims made by the traditional medical practitioners and to evaluate the plant’s potential as a novel therapeutic agent. Twelve traditional medical practitioners of the Kopanang Dingaka Association were interviewed on the knowledge and use of I. oblongata (Mothokho). The phytochemical constituents of the plant were determined using standard screening methods. Testing for antioxidant properties (free radical scavenging activity) was carried out by means of the 2, 2- diphenylpicrylhydrazyl (DPPH) assays. The Sulforhodamine B assay was used to screen for anti-cancer activity in breast (MCF7), colon (HCT116) and prostate (PC3) cancer cell lines. Glucose uptake in C2C12 muscle cells was used to evaluate the anti- iii diabetic potential of I. oblongata. Methanol extract was fractionated using Ultra-Pure Liquid Chromatography (UPLC) to identify active compounds. The traditional medical practitioners cited the plant roots as the main ingredient in the treatment of respiratory infections, sexually transmitted infections, postnatal womb treatments, inflammation, arthritis, wounds and cancer. The methanol extract of I. oblongata showed remarkable (99.03%, 98.39, 71.31%) antioxidant potential in all triplicates tested which explains its use in oxidative stress-related diseases such as arthritis and cancer. Phytochemical tests showed the presence of carbohydrates, glycosides, steroids, terpenoids, alkaloids, flavonoids and tannins. However, the extracts were inactive against the cancer cell lines used. Glucose uptake by the C2C12 muscle cells was increased by over 150% and was comparable to that of insulin and metformin, suggesting good anti-diabetic activity. Predicted compounds found were dihydroquercetin pentaacetate, actinorhodin and actinorhodine, using Chemspider analysis. These are possible compounds that could be found in the Ipomoea oblongata extracts when using nuclear magnetic resonance (NMR) to determine the structure and names of the active compounds. Ethnobotanical uses of Ipomoea oblongata were found to have a link with other ethnobotanical studies to capture the indigenous knowledge, culture and therapeutic uses. The phytochemical results of Ipomoea oblongata can contribute to the knowledge of new drug development as indicated by literature (Harbone; 1973, Soforowa, 1993; De et al., 2010) that plants contain phytochemical contents and phenolic compounds that are valuable as medicinal properties. Methanolic extract of Ipomoea oblongata presented high levels of antioxidant activity respectively, which can become a potential iv antimicrobial agent and remedy oxidative stress related diseases. The anticancer properties were inactive and the cytotoxicity levels were found to below in I. oblongata. Low levels of cytotoxicity allow medicinal plants to be consumed by humans with fewer side effects however doses must be standardized. High levels of glucose uptake in muscle cells were indicated from the aqueous extract of Ipomoea oblongata, therefore showing great potential as an antidiabetic agent. Many medicinal plants have been validated as antidiabetic therapeutic agents in South Africa and the world. New treatment of cancer, diabetes, bacterial and viral infections is required from natural products that are cost effective with minimal side effects that can be used in health care systems. There is a correlation between the medicinal properties found in I. oblongata and the ethnomedicinal uses cited by the traditional medical practitioners. The plant I. oblongata has six ethno-pharmaceutical uses. I. oblongata is a good source of anti-diabetic and antioxidant agents that can be developed further. However the plant is not a good source of anticancer properties. Future research will be into the isolation and identification of the active compounds.
109

Antioxidative, analgesic and anti-inflammatory activities of Acokanthera oppositifolia, Plantago lanceolata, Conyza canadensis, and Artemisia vulgaris

Ondua, Moise 02 1900 (has links)
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)
110

Intellectual property rights and the protection of traditional knowledge in Western Cape agriculture

Daya, Yusuf 12 1900 (has links)
Thesis (MComm)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: This study analyses the extent to which the current intellectual property system is suited to the protection of traditional knowledge in the Western Cape. Employing a multidisciplinary approach that incorporates economic and legal theory as well as legal philosophy, this study argues that although advances in the fields of biotechnology has brought with it the need for greater intellectual property rights protection, the protection of traditional knowledge has largely been ignored. Traditional ethnobotanical knowledge holds immense economic value for both commercial entities seeking to develop products based on traditional knowledge as well as for the communities that possess such knowledge. Protecting traditional knowledge is necessary to ensure that the communities contributing their knowledge are recognized and compensated for such contributions. In order for a system to provide adequate protection for traditional knowledge it has to be consistent with and suited to the needs of traditional knowledge holders. This study therefore evaluates the prevailing system of knowledge protection as embodied in the intellectual property rights regime as a means of protecting traditional knowledge. The analysis reveals that the dominant justification for the existence ofIPRs is based on utilitarian considerations that promote IPRs as a necessary incentive encouraging innovative activity. This utilitarian justification also provides the basis for an economic justification for the existence of IPRs that suggests that the conferring of exclusive rights (in the form of IPRs) to innovators ensure that such innovators are able to recover their research costs and realize profits from their inventions. The IPR system as it exists is underpinned by these considerations and embedded in principles of individualism and private property. The WTO reinforces and promotes this approach to intellectual property in the TRIPs agreement by recognizing intellectual property as a 'trade related' issue. The inclusion of IPRs as a 'trade related' issue in the multilateral framework of the WTO reflects the interests of multinational corporations and developed nations who rely extensively on these mechanisms to maintain their power and wealth in an increasingly knowledge driven global economy. The exclusion of traditional knowledge within the TRIPs, coupled with the desire to extend patents to cover life forms is also indicative of this bias inherent in the system. South African intellectual property legislation is then applied to the traditional knowledge of an indigenous medicinal plant to test whether IPRs are able to provide adequate protection to traditional knowledge. In this regard it is found that patent protection, which could potentially provide the greatest form of protection for traditional knowledge is. not suited to the needs of traditional knowledge holders. Problems of identifying owners, determining inventors and novelty, time limited rights and costs all limits the potential of patents as a tool for protecting traditional knowledge. Similar constraints limit the potential of other categories of IPRs to provide protection for traditional knowledge. However, it was found that IPRs do provide a certain measure of defensive protection. The study therefore concludes that the IPR system as it exists, both in the international trade environment as well as at the national level, fails to adequately address the threat of appropriation and the concerns of traditional knowledge holders. Amending the IPR system and/or developing sui generis systems of protection are therefore necessary to ensure that the knowledge of communities are protected and such communities are able to benefit from the exploitation oftheir knowledge and resources. / AFRIKAANSE OPSOMMING: Die doel van hierdie studie is om vas te stel in hoe 'n mate die huidige sisteem vir die beskerming van intellektuele eiendom geskik is vir die beskerming van tradisionele kennis in die Wes-Kaap. 'n Multidissiplinêre benadering, wat uit elemente van ekonomiese- en regsteorie sowel as regsfilosofie haal, is gevolg om te wys dat die beskerming van tradisionele kennis grootliks geïgnoreer is, alhoewel nuwe deurbrake in biotegnologie die behoefte skep vir groter bekerming van intellektuele eiendom. Tradisionele etnobotaniese kennis het geweldige ekonomiese waarde vir beide die kommersiële entiteite wat produkte uit sodanige kennis wil produseer sowel as vir tradisionele gemeenskappe aan wie die kennis behoort. Dus, indien sulke gemeenskappe voordeel wil trek uit hierdie kennis, is dit nodig dat hul bydraes erken moet word, en dat hulle daarvoor vergoed moet word. Sulke beskerming sal net doeltreffend wees indien dit aangepas is by die behoeftes van hierdie gemeenskappe. Dus word die huidige sisteem vir die beskerming van tradisionele kennis geevalueer in hierdie studie. Die ondersoek wys dat die sisteem vir die beskerming van intellektuele eiendom berus op die teoretiese basis van nutsmaksimering, waar die hoofdoel te vinde is in die bydrae wat dit kan maak tot ekonomiese welvaart deur middel van innovasie. In hierdie opsig word beskerming van intellektuele eiendom beskou as 'n manier waardeur die innoveerder sy navorsings- en ontwikkelingskostes kan delg en wins kan maak. Hierdie benadering word onderskryf deur die WTO in die TRIPS Ooreenkoms. In hierdie opsig word die belange van veral die ryk lande en die multinasionale maatskappye bevorder, 'n sleutelvoordeel in 'n wêreld waar kennis gepaardgaan met mag in die mark. Hierdie verskynsel word versterk deur die uitsluiting van tradisionele kennis van die TRIPS Ooreenkoms en die behoefte daaraan om patentregte uit te brei. Suid-Afrikaanse wetgewing oor intellektuele eiendom word vervolgens toegepas op die geval van tradisionele kennis oor 'n inheemse medisinale plant om te toets of intellektuele eiendomsreg genoegsame beskerming aan tradisionele kennis bied. Daar is gevind dat patentregte, wat potensieël die grootste mate van beskerming sou kon bied, nie gepas is in die geval van houers van tradisionele kennis nie. Probleme wat voorkom sluit in die identifisering van eienaars, innoveerders en innoverings, die tydsbeperking op regte, asook kosteoorwegings. Ander vorms van beskerming is aan soortgelyke kritiek onderhewig, alhoewel bevind is dat intellektuele eiendomsreg wel 'n mate van defensiewe beskerming bied. Die gevolgtrekking word dus gemaak dat die huidige vorms van beskerming vir intellektuele eiendomsreg, beide internasionaal sowel as in Suid-Afrika, nie die belange van die houers van tradisionele kennis beskerm nie. Dit is dus nodig om die huidige vorms aan te spreek, of om sui generis beskerming te ontwikkel om hiervoor te sorg.

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