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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.
111

Knowledge and use of traditional medicinal plants by the Setswana-speaking community of Kimberley, Northern Cape of South Africa

Monakisi, Charlotte M. 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: The majority of South Africans still depend on the use of traditional remedies, as these are sometimes the only types of health care systems available, especially within rural communities. South Africa comprises approximately 400 000 traditional healers and an estimated 60 to 80% of individuals consulting such traditional healers. As a result, the over-harvesting of many traditional medicinal plants has become a threat to the country’s species diversity and has resulted in the scarcity of certain medicinal plant species. The non-sustainable use of traditional medicinal plants stems from their intense harvesting from the wild to supply the high demands from urban and rural markets. As a result of the escalating population growth rate; high rural unemployment; and fundamental value attached to traditional medicinal plants (socio-economic factors), the national and regional trade of traditional medicines is currently higher than it has ever been. Another reason for the increased threat to traditional medicinal plants is the degradation and weakening of customary laws that have previously regulated such resources. This study focuses on the use of traditional medicinal plants by the Setswana-speaking community for self-medication and as a form of primary health care. Research was conducted in Kimberley, Northern Cape of South Africa and focuses on the issue of the sustainability of medicinal plant use in the area, specifically on use and users as well as the acquisition of material sold by a single trader and harvesting techniques. This is to determine whether harvesting of medicinal plants is a potential threat to plant communities in the area. To address the shortcomings of medicinal anthropology the study also investigates the impacts of relocation and resettlement of various communities in the area, on plant use, methods of collection, the sustainability of the natural resource, as well as the transmission of Setswana indigenous knowledge inter-generationally. most abundant under high disturbances. Certain species reacted positively to disturbance and were most abundant in disturbed habitats. These included Elephantorrhiza elephantina and a Helichrysum sp. To minimise destructive harvesting in the Kimberley area and to ensure the sustainable harvesting of plant material, it is important that local harvesters are educated on proper harvesting techniques and that local gatherers are educated on sustainability issues as well as other ecologically fundamental issues. / AFRIKAANSE OPSOMMING: Die meeste Suid-Afrikaners is steeds afhanklik van tradisionele geneesmiddels aangesien dit soms, veral in landelike gemeenskappe, die enigste beskikbare gesondheidsorg is. Suid-Afrika het sowat 400 000 tradisionele geneeshere wat deur ’n geraamde 60% tot 80% van individue geraadpleeg word. As gevolg hiervan hou die oorontginning van talle tradisionele medisinale-planthulpbronne ’n bedreiging vir die land se spesiediversiteit in en het dit reeds tot ’n skaarste aan sekere medisinale plante gelei. Tradisionele medisinale plante word tans nievolhoubaar aangewend aangesien dit op groot skaal in die veld geoes word om in die groot vraag van stedelike en landelike markte te voorsien. As gevolg van die stygende bevolkingsgroeikoers, hoë landelike werkloosheidsyfer en die grondliggende waarde wat aan tradisionele medisinale plante geheg word (sosio-ekonomiese faktore), is die nasionale en streekhandel in tradisionele geneesmiddels tans groter as ooit tevore. Nog ’n rede vir die toenemende bedreiging van tradisionele medisinale plante is die verslapping en versagting van gewoonteregwetgewing wat voorheen sodanige hulpbronne gereguleer het. Hierdie studie fokus op die gebruik van tradisionele medisinale plante deur die Setswanagemeenskap vir selfbehandeling en as ’n vorm van primêre gesondheidsorg. Die navorsing vir die studie is in Kimberley in die Noord-Kaapprovinsie van Suid-Afrika gedoen en fokus op die kwessie van volhoubare medisinale-plantgebruik in die gebied, met bepaalde klem op gebruik en gebruikers, die verkryging van middels wat deur ’n enkele handelaar verkoop word, en oestegnieke. Die doel van die navorsing was om te bepaal of die oes van medisinale plante ’n moontlike bedreiging vir plantgemeenskappe in die gebied inhou. Om die tekortkominge van medisinale antropologie aan te pak, ondersoek die studie ook die uitwerking van die verskuiwing en hervestiging van verskeie gemeenskappe in die gebied op plantgebruik, oesmetodes, die volhoubaarheid van die natuurlike hulpbronne, asook die oordrag van inheemse Setswana-kennis oor geslagte heen. Selfbehandeling en die gebruik van tradisionele medisinale plante speel steeds ’n groot rol in Kimberley, aangesien die meeste van die individue wat aan die navorsing deelgeneem het steeds tradisionele geneesmiddels as deel van hulle kultuur en tradisie gebruik. Daar word in ’n uiteenlopende verskeidenheid plantmateriaal handel gedryf. Hoewel sommige van die middels plaaslik ingesamel word, word die meeste van ander dele van die land, en in party gevalle van buurlande soos Lesotho en Swaziland, ingevoer. Hoewel die meeste van die materiaal dus nie plaaslik ingesamel word en dus nie bepaald op hierdie studie betrekking het nie, is dit steeds aanduidend van oes- en volhoubaarheidskwessies in ander dele van die land. Die kruiekenner dryf in sewentig tradisionele medisinale-plantsoorte handel, waarvan party beskermd en erg bedreig is, waaronder Prunus africana en Warburgia salutaris wat slegs in beskermde gebiede in die land voorkom. Prunus africana is ’n gelyste spesie in CITES, aanhangsel 2. Ander bedreigde spesies sluit Ocotea bullata, Bersama lucens, Curtisia dentata en ’n Eugenia-spesie in. Die meeste van die plante wat (in Kimberley) geoes word, is in die vorm van ondergrondse bergingsorgane (uitlopers en bolle). Hoewel hierdie plante van stingelskade en die skade aan ondergrondse bergingsorgane kan herstel, vat hulle swak pos indien hulle oorgebruik en oorontgin word, en kan hulle dus mettertyd al hoe minder voorkom. In hierdie studie word die mettertydse afname in plantbevolkings deur die toename in reisafstande na insamelingspunte aangetoon. Hierdie tendens is egter nie in die handelsprys en -materiaalhoeveelhede oor die afgelope eeu weerspieël nie. Die meeste van die studiedeelnemers het bevestig dat die prys en hoeveelheid van die handelsmateriaal deurentyd betreklik stabiel gebly het. Van die teikenspesies wat vir kwesbaarheid of sensitiwiteit vir ontwrigting ondersoek is, het Withania somnifera, Boophane disticha, Dicoma anomala en Bulbine natalensis die laagste oorlewingspotensiaal en die hoogste ontwrigtingsensitiwiteit getoon. Die meeste van hierdie spesies het in baie klein hoeveelhede op die gekose terreine voorgekom. In die geval van Withania somnifera kon die negatiewe resultate egter met die laereënvalseisoen gedurende daardie betrokke jaar in verband gebring word. Hierdie spesie word oor die algemeen as ’n onkruid in ontwrigte gebiede geklassifiseer en kom meestal onder erg ontwrigte toestande voor. Sekere spesies, soos Elephantorrhiza elephantina en ’n Helichrysum-spesie, het positief op ontwrigting gereageer en het volop in ontwrigte habitatte voorgekom. Om vernietigende oestery in die Kimberley-omgewing te minimaliseer en die volhoubare ontginning van planthulpbronne te verseker, is dit belangrik dat plaaslike plukkers in gepaste oestegnieke, en plaaslike insamelaars oor volhoubaarheidskwessies en ander ekologies belangrike sake opgelei word.
112

In vitro propagation of Agathosma betulina an indigenous plant of economic importance

Witbooi, Hildegard January 2013 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Horticultural Sciences in the Faculty of Applied Sciences at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY Supervisor: Dr L Kambizi Co-supervisor: Dr NP Makunga Cape Town December 2013 / Agathosma betulina (Berg.) Pillans, previously known as Barosma betulina, is a member of the Rutaceae family, and indigenous to the fynbos botanical biome of the Western Cape of South Africa. It is commonly known as buchu. Extracts as well as powdered leaves have traditionally been used for the treatment of various ailments. The increase in the international demand for A. betulina for health as well as food and beverage benefits, have raised concerns over exploitation of wild populations and the lack of horticultural information necessitates this study to evaluate the propagation of this economical important species. The main objective of this study was to establish a simple and highly productive micropropagation protocol for A. betulina through experimenting with nodal explants. Testing of the effect of various treatments (physical scarification, chemical scarification, GA, stratification, smoke and combinations thereof) on the in vitro germination of A. betulina seeds was done to elucidate the factors which control seed germination. The study revealed that the physical scarification and smoke-induced germination had a significant effect on germination percentages. In terms of germination rate, the radical generally started to appear after approximately 10 days in the physical scarification with smoke treatment. Initial decontamination methods with the exposure of various concentrations of NaOCl gave fatal results, however 1.5% NaOCl had more phenolic reactions rather than fungal or bacterial contamination. Interestingly, contamination rates of explants were influenced by the stage of maturity of the explant material. This plant material was used to test different strengths of regeneration media, to ensure that the explants receive ample nutrients. Results made exhibited that ½ MS was the best strength for growing A. betulina nodal explants. Compared comparison between in vitro derived explants and ex vitro collected explants showed that the ex vitro derived explants had significant results, but the explants lost vigour soon after the initial exponential growth leading to the explants dying off. Furthermore, ex vitro decontaminated plant material was not economically viable to continue with. Seedlings derived from germinated seeds appeared to be the preferred method of propagation as this spent the least time in culture and produced a stable plant with an established root system, which is essential during the hardening off process after in vitro growth. When exposing nodal explants to phytohormone 2,4-D it responds best to dosages 0.5mg Lˉ¹ and 1mg Lˉ¹. Phytohormone BA was very effective in producing soft friable callus. The best results were shown when 0.5mg Lˉ¹ BA was applied to ½ MS media. For both shoot length and multiple shoot production, a combination of phytohormones BA-NAA (1: 0.5mgLˉ¹) had the most significant results. Interestingly, a higher phytohormone concentration of NAA is necessary to develop multiple adventitious roots. The effect of 3mg Lˉ¹ was significant in that it resulted in multiple adventitious roots, but fewer calli was observed in this treatment. Micropropagation becomes valuable as little attention between subcultures is needed; making it less labour intensive compared to conventional nursery propagation systems where weeding watering and spraying of plants are labour intensive. In the traditional world of medicine, more so in Southern Africa, extracts are prepared by adding boiling water to the plant material; however commercial ethanol is used as an extractant. Establishment of the essential oil quality of the in vitro cultures post exposure to various treatments was done. Analysis of essential oils from A. betulina resulted in the identification of twenty one compounds. The results showed qualitative as well as quantitative differences amongst the samples used in the study. The highest relative concentration of limonene was observed in the callus of nodal explants after it was exposed to 0.5mg lˉ¹ NAA. No pulegone was found in this treatment making it ideal for limonene production. This suggests that liquid culture with the same treatment may produce more calli making it ideal for the production of limonene.
113

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)
114

Social learning processes of HIV/AIDS women caregivers on their use of traditional foods and medicinal plants : the case of Raphael Centre and Keiskamma Art and Health Centre communities of practice, Eastern Cape Province, South Africa

Shonhai, Venencia F January 2009 (has links)
The scale of people being infected by HIV/AIDS (Human Immunodeficiency Virus /Acquired Immune Deficiency Syndrome) has meant that the family and the community have had to become involved in caring for the sick (Van Dyk, 2005). This has inevitably led to the emergence of informal caregivers in the form of family members caring for their relatives (Kipp, Nkosi, Laing & Jhangri, 2006). The research investigated the social learning of women caregivers looking after people living with HIV/AIDS, with emphasis on caregiving practices related to how they use traditional foods and medicinal plants. The research was undertaken in Grahamstown at the Raphael Centre and in Hamburg at Keiskkamma Health Centre and Art Project, Eastern Cape, South Africa. Data was collected using interviews, focus group discussions and diaries written by participants. The data was analyzed in two phases: the first phase involved reading the interview transcripts and collating the responses into analytical memos that were captured into broad categories, while the second phase made use of the community of practice analytical framework to further analyze the data to get better understanding of the social learning processes. This study reveals that participating in a community of practice like Raphael Centre and Keiskamma Health Centre enables caregivers to learn about caregiving. It also reveals that within these communities of practice there are varied learning processes that take place, such as observational and collaborative learning. The research also revealed that caregivers learn from the communities from which they come, for example caregivers learn about traditional food and medicinal plants which they use from their family members, friends, other caregivers as well as non governmental organizations. The research found that caregivers are influenced in their learning and practices by a number of factors which include their own experiences, ambivalent messages from different stakeholders concerned with fighting HIV/AIDS and exposure to new information. The research recommends that diverse learning processes in a community of practice and outside a community of practice should be encouraged and strengthened. It also recommends that HIV/AIDS caregiving options should be strengthened by drawing on experience and knowledge of caregivers. Caregivers should be encouraged to be selfsustaining to improve their caregiving practices. Stakeholders in the field of HIV/AIDS should be alert to and address ambivalence on use of medicinal plants. Existing programmes that enable women to learn about new information on HIV/AIDS should be strengthened.
115

The ethnobotany and pharmacognosy of selected Cape herbal medicines

Long, Helen Selma 01 July 2014 (has links)
M.Sc. (Botany) / A few poorly studied Cape herbal medicinal plants of historic and potential commercial interest which form part of the traditional medicine system of the Cape Region have been selected for this study. These are Centella glabrata L., Olea europaea L. subsp. africana (Mill.), Rafnia amplexicaulis (L.) Thunb. and Tulbaghia alliacea L.f. Centella C. asiatica is mainly used to treat skin conditions and wounds, tuberculosis and coughs and cooked and eaten as a vegetable in South Africa. The treatment of heartburn in the Wild Coast is a recent record. Decoctions of the leaves and stalks of C. glabrata were used for treating diarrhea and dysentery by the early Cape settlers. C. stenophylla or “klipdagga” is used in the treatment of high blood pressure and diabetes in the Still Bay area. This is also a recent new record. The anatomy of the few Centella species studied differed dramatically both in the leaf lamina and the petiole and could be used to differentiate between the species studied. A wider study would be very interesting and could be useful to distinguish between the species. This could have great potential as the ca. 45 species of Centella are often very difficult to distinguish from one another.
116

Development of conservation methods for gunnera perpensa l.: an overexploited medicinal plant in the Eastern Cape, South Africa

Chigor, Chinyere Blessing January 2014 (has links)
South Africa, many plants which are used in traditional medicines are collected from wild populations. The high demand for trade and use of these medicinal plants place an enormous pressure on their natural populations, especially because they are indiscriminately harvested. The most affected of these plant species are those harvested from their underground parts, among which is Gunnera perpensa L. Gunnera perpensa is of considerable ethnobotanical interest in traditional medicine because of its wide usage. The rhizomes are widely used and indiscriminately collected in large quantities from the wild to meet the ever increasing demand in traditional medicine markets. As a result, this valuable medicinal plant species is being endangered. According to the Red List of South African Plants, the conservation status of G. perpensa has been listed as ‘declining’. The ethnobotanical survey conducted as part of this research confirms the plant species as threatened. It is, therefore, important to develop propagation and conservation strategies for this medicinal plant. Clonal propagation of G. perpensa was conducted using varying lengths of the rhizome (1, 2, 3, 4 and 5 cm) segments as propagules. While regeneration was possible with all the rhizome lengths, most of the growth parameters were significantly higher in the 5 cm rhizomes than the other rhizome segments. The appropriate planting depth for the rhizomes was also determined and 4 or 5 cm planting depths were found appropriate. No significant difference was observed in the growth parameters amongst the planting depths; nevertheless, 4 cm depth gave higher growth and yield. The results of this study show that regenerating G. perpensa.
117

Determination and validation of plants used by resource-limited farmers in the ethno veterinary control of gastro-intestinal parasites of goats in the Eastern Cape Province, South Africa

Maphosa, Viola January 2009 (has links)
No description available.
118

Heavy metal content absorption and medicinal potential of Egeria densa (Planch.) Casp

Mgobozi, Vuyokazi January 2013 (has links)
The contamination of heavy metals in the environment is a looming concern worldwide. Egeria densa (Planch) (Submerged aquatic plant) from two ponds: Site A with co-ordinates (32º 48’22.04”S; 26°48’58.79” E) and Site B with co-ordinates (32°48’33.25”S; 26°48’33.25”S) in Alice (Eastern Cape) was evaluated for its ability to absorb heavy metals, phytochemical constituents, antimicrobial activity and ultra-structure using standard analytic procedures. Cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), and zinc (Zn) were measured in water, sediments and plant. The concentrations of these metal elements were determined with use of Inductively Coupled Plasma- Optical Emission Spectrometry (ICP-OES). In sediments, the heavy metals (mg/kg) decreased in the order of their average concentration as follows: Fe (40.320) > Zn (1.259) > Pb (0.564) > Mn (0.186) > Cu (0.037) in Pond 1 whereas in Pond 2 Fe (61.527) > Cd (0.999) > Mn (0.648) > Pb (0.586) > Zn (0.156) > Cu (0.045). The highest concentration of Fe was detected in both sites and Cu being the least. The concentrations of the metals in the plants sample (from Pond 1) were found in order of Mn > Pb > Cu > Fe whereas cadmium and zinc were not detected, while the concentration in Pond 2 decreases in order of Zn > Mn > Pb > Cd > Fe > Cu. In the water samples, concentrations of heavy metals (mg/L) decreased in the order of their average concentrations as follows: Pb (35.36) > Fe (3.07) > Mn (0.238) > Cu (0.104), both cadmium and zinc were below the limit of detection in Pond 1, whereas in Pond 2 the concentrations decreased as follows: Pb (13.033) >Fe (1.69) > Cu (0.270) > Mn (0.248) > Cd (0.004) and Zinc was not detected. Phytochemical analyses of the plant extracts revealed the presence of phenols, flavonoids, proanthocyanidin, flavonols, saponins, alkaloid and tannins in all the extracts (water, acetone and n-hexane). Both acetone and water extracts, showed high concentration of proanthocyanidin, while tannin was the lowest in acetone extract. Antimicrobial evaluation using, Gram positive (Staphylococcus aureus, Bacillus pumilus, Bacillus cereus, Streptococcus pyogenes, Enterococcus faecalis) and Gram negative (Klebsiella pneumonia, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris and Serratia marcescens) bacteria showed negative results for all the strain, except Streptococcus pyogenes which was inhibited at MIC of 0.1 mg/ml. Scanning electron microscopy (SEM) of ultra-structure of Egeria densa, showed that certain bacteria attached to the leaf, However more work has to be done on E. densa to verify the mechanism by which it accumulates heavy metals. The study shows that E. densa has a potential of accumulating heavy metals especial Manganese in plant.
119

The efficacy and toxicological effects of aloe ferox mill. used in the management of constipation in Nkonkobe municipality of the Eastern Cape province, South Africa

Wintola, Olubunmi Abosede A January 2011 (has links)
Herbal remedies are commonly used in developing countries for the treatment of various diseases, including constipation. The rationale for utilizing medicinal plants for the treatment of diseases rested largely on the belief that they are safe and free of side effects. However, there is limited scientific evidence on the safety and efficacy of these herbal medicines to back up their continued therapeutic application. Aloe ferox Mill. (Aspodelaceae), known as Cape aloe, locally called ikhala is a medicinal plant used by the people of the Eastern Cape Province for the treatment of gastrointestinal problems and constipation. The plant is a perennial shrub with thick succulent leaves bearing brown thorns on the margin and bright orange flowers arranged in oval lanceolate. It occurs in all weather in bush veld, road side, gardens and undisturbed places. According to the ethnomedicinal information, A. ferox is used as purgative. This research project was therefore designed to evaluate its ability in the treatment of constipation and to investigate its possible toxicological property. At the beginning of this programme, a survey of plants used for the treatment of constipation in Nkonkobe Municipality of the Eastern Cape Province was carried out using a questionnaire, which was administered to herbalists, traditional healers and rural dwellers. The study revealed 10 plant species from 8 families that are used for the treatment of constipation in the province. Four plants, Aloe ferox Mill, Boophone distischa L.f Herb, Alepidea amatybica Eckl and Artemisia afra Jacq, were repeatedly mentioned. Based on the frequency of usage, perceived efficacy and availability to the rural dwellers and the traditional healers, Aloe ferox was the most commonly used of the plants for the treatment of constipation. The plant was thus, chosen for the study. The invivo laxative effect of the aqueous extract of Aloe ferox in the treatment of loperamide-induced constipation in Wistar rats was investigated at varying concentrations. The leaf extract at all the dosages investigated (50, 100 and 200 mg/kg body weight) improved intestinal motility, increased fecal volume and normalized body weight in the constipated rats. This was an indication of its laxative properties. However, the laxative property of the herb at 200 mg/kg body weight of the extract showed best efficacy and compares favourably well with senokot, a standard laxative drug. These findings have therefore, lent scientific credence to the folkloric use of the herb by the people of the Eastern Cape of South Africa as a laxative agent. Toxicological evaluation of aqueous leaf extract of Aloe ferox in loperamide-induced constipation was studied at 50, 100, and 200 mg/kg body weight. The oral administration of the extracts did not show any significant effect on the liver and kidney body weight ratios as well as the kidney and liver function indices. The extracts, at all the dosages investigated, did not alter the levels of creatinine, uric acid, urea, calcium and potassium ions. Similarly, the levels of total protein, albumin, bilirubin and gamma glutamyl transferase (GGT) were not significantly different from the control. The plant extract appreciably normalized the elevated activities of alkaline phosphatase (ALP), alanine transaminase (ALT) and aspartate transaminase (AST) in the untreated constipated rats following treatment with the extract. The extract did not show a significant effect on the hematological parameters except for the increase in the lymphocyte count in the untreated constipated rats, which was attenuated after administering the herb. ThThe available evidence in this study suggests that A. ferox may be safe as an oral remedy for constipation. Generally, the effect of the extract compared favourably well with senokot, a recommended drug for the treatment of constipation. The antioxidant activities against 1, 1 diphenyl- 2 picrylhydrazl (DPPH), 2,2’ – azinobis [3- ethylbenzothiazoline -6- sulfonic acid] diammonium salt (ABTS), hydrogen peroxide (H2O2), Nitric oxide (NO), lipid peroxidation and the ferric reducing agents were investigated spectrophotometrically. Alkaloids, saponins, tannins, total phenols, flavonoids, flavonols and proanthocyanidin were also determined to assess their effects on the antioxidants activity of this plant. The phytochemical content of the ethanol and acetone extracts were consistently high compared to other solvents extracts. The level of tannins was not significant (P > 0.05) as compared with other solvent extracts. The free radical scavenging activity of the extracts was high even at lower concentrations (0.025 mg/ml) except in DPPH and lipid peroxidation. The ferric reducing potential of the extracts was concentration dependent and significantly different from Vitamin C and butylated hydroxytoluene (BHT) that were used as standard drugs. The present study showed a high level of scavenging activity of the leaf extracts of Aloe ferox in all the solvent extracts. Both ethanol and methanolic extract showed potent antioxidant activities than acetone and aqueous extracts. The study indicated that the leaf extracts of Aloe ferox might be a valuable source of natural antioxidant for both medicine and food industries. A. ferox leaf consists of the gel, latex and mesophyll layer; however, the main active constituents of the latex and the leaf exudate of Aloe ferox are anthraquinones which are believed to be responsible for the laxative property. The laxative compound in Aloe ferox leaf extract was isolated and characterized by extracting the plant material in methanol and extract suspended in distilled water. Partitioning was done with n-hexane, ethyl acetate and butanol respectively and was co-spotted with the over-the-counter (OTC) laxative drugs. This led to the successive column chromatography and thin layer chromatography (TLC) of the most active ethyl acetate fraction on silica gel with benzene/ethanol/ammonia hydroxide (BEA: 90:10:1), ethyl acetate/methanol/water (EMW: 40:5.4:5) and chloroform/ethyl acetate/formic acid (CEF: 50:40:10) as the mobile phase. The successive chromatograph and TLC afforded two compounds of Rf 0.420 (blue) and 0.831 (yellow) with the over-the-counter (OTC) drugs. These compounds were not totally elucidated due to their small quantity and instability. However, hydroxyl (OH) and carboxyl groups (COOH) was established as common to the extracted compounds, which might be responsible for the biological activity recorded for the plant extract.
120

Bioactivity and phytochemical analysis of Hydnora Africana on some selected bacterial pathogens

Nethathe, Bono Bianca January 2011 (has links)
Abstract Medicinal plants have been for long remedies for human diseases because they contain components of therapeutic value. The growing problem of antibiotic resistance by organisms demands the search for novel compounds from plant based sources. The present study was aimed at evaluating the bioactivity and phytochemical analysis of Hydnora africana on clinical and standard strains of Helicobacter pylori (PE 252C and ATCC 43526), Aeromonas hydrophila ATCC 35654, and Staphylococcus aureus NCT 6571 in an effort to identify potential sources of cheap starting materials for the synthesis of new drugs against these strains. Ethyl acetate, acetone, ethanol, methanol, and water crude extracts of H. africana were screened for activity against the test organisms using the agar well diffusion assay. The Minimum Inhibitory Concentration (MIC50) and Minimum Bactericidal Concentration (MBC) of the most potent extracts were determined by the microdilution method, followed by qualitative phytochemical analysis. Results were analyzed statistically by ANOVA one - way test. Different concentrations (200,100, 50mg/mL) of the methanol, acetone, ethanol and ethyl acetate extracts showed activity against S. aureus and A. hydrophila while for H. pylori, only methanol and ethyl acetate extracts were active; water showed no activity for all studied bacterial pathogens. Mean zone diameter of inhibition which ranged from 0-22mm were observed for all test bacterial pathogens and 14-17mm for ciprofloxacin. The activity of methanol and ethyl acetate extracts were statistically significant (P< 0.05) compared to all the other extracts. MIC50 and MBC ranged from 0.078 – 2.5mg/mL, 0.78-25mg/mL respectively for all tested bacterial pathogens. For ciprofloxacin, the MIC50 and MBC ranged from 0.00976 – 0.078mg/mL and 0.098– 0.78mg/mL respectively. There was no statistically significant difference between extracts (methanol, acetone, ethanol, ethyl acetate) and the control antibiotic (ciprofloxacin) (P> 0.05). Qualitative phytochemical analysis confirmed the presence of alkaloids, saponins, steroids, tannins and flavonoids in the methanol, acetone,ethanol and ethyl acetate extracts. The results demonstrate that H. africana may contain compounds with therapeutic potentials which can be lead molecules for semi-synthesis of new drugs.

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