List of Titles

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

Authors: Wintola, Olubunmi Abosede A
Date: 2011
Subjects: Asphodelaceae -- South Africa -- Eastern Cape , Aloe -- South Africa -- Eastern Cape , Herbs -- Therapeutic use -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Constipation -- South Africa -- Eastern Cape , Poisonous plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Doctoral , PhD (Ethnobotany)
Identifier: vital:11882 , http://hdl.handle.net/10353/485 , Asphodelaceae -- South Africa -- Eastern Cape , Aloe -- South Africa -- Eastern Cape , Herbs -- Therapeutic use -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Constipation -- South Africa -- Eastern Cape , Poisonous plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape
Description: 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.
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Date Issued: 2011

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Assessment of the flocculating efficiency of bioflocculant produced by bacillus sp. Aemreg4 isolated from Tyhume river, Eastern Cape, South Africa

- Ntsangani, Nozipho

Authors: Ntsangani, Nozipho
Date: 2016
Subjects: Flocculants
Language: English
Type: Thesis , Masters , MSc (Biochemistry)
Identifier: vital:11357 , http://hdl.handle.net/10353/d1021324
Description: Bioflocculants are flocculating substances produced by microorganisms during growth and have recently received considerable attention from researchers; due to their biodegradability, non-toxicity and lack of secondary pollution from degradation intermediates. This study evaluated the efficiency of bioflocculant produced by Bacillus sp. AEMREG4 isolated from Tyhume River. The bacterial identification was through 16S rDNA sequencing; nucleotide sequences were deposited in GenBank as Bacillus sp. AEMREG4 with an Accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size of 4% (v/v) and starch as well as yeast extract as sole carbon and nitrogen sources respectively. The addition of CaCl2 enhanced the flocculating activity, at a wide range of pH 4-10 and the highest flocculating activity was reached at an initial pH 8 (80%). A bioflocculant yield of 0.78 g was recovered from 1 L of culture broth. The optimum flocculating activity of 78% was reached at the lowest bioflocculant dosage of 0.1 mg/ml and the presence of divalent cations (Ca2+, Mn2+ and Mg2+) as well as a trivalent cation (Al3+) enhanced flocculating activity. The purified bioflocculant retained more than 70% flocculating activity when subjected to heating at 100 °C for 1 h and maximum flocculating activity of 83% was achieved at both acidic and basic pH values of 3 and 10 respectively. Chemical analysis showed that the bioflocculant is predominantly polysaccharide. The Fourier transform infrared (FTIR) spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional moieties and the scanning electron microscopy (SEM) imaging of the purified bioflocculant showed its morphological structure as rod-shaped which contributes to its high flocculating efficiency. The high flocculation activity displayed by this bioflocculant indicates its potential suitability for industrial application.Keywords: Bioflocculant, Bacillus sp. AEMREG4, flocculating activity.
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Date Issued: 2016

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Validating the use of Hippobromus pauciflorus (L.f) Radlk for the treatment of eye infections in the Eastern Cape South Africa

- Pendota, Srinivasa Chary

Authors: Pendota, Srinivasa Chary
Date: 2010
Subjects: Medicinal plants -- South Africa -- Eastern Cape , Herbs -- Therapeutic use , Eye -- Infections -- South Africa -- Eastern Cape , Sapindaceae
Language: English
Type: Thesis , Doctoral , PhD (Botany)
Identifier: vital:11303 , http://hdl.handle.net/10353/d1001052 , Medicinal plants -- South Africa -- Eastern Cape , Herbs -- Therapeutic use , Eye -- Infections -- South Africa -- Eastern Cape , Sapindaceae
Description: An ethnobotanical survey of plants used for the treatment of eye infections was carried out in the Eastern Cape Province of South Africa. The study revealed that 12 plant species are commonly used with Hippobromus pauciflorus (L.f) Radlk being the most frequent. The crude extracts of the leaves, stem bark and roots of the plant were investigated for antimicrobial activity against 10 bacterial and four fungal strains. The methanol extracts of the plant parts were the most active and showed appreciable activity against Gram-positive and Gram-negative bacteria. The methanol extracts of the leaves and stem bark inhibited the growth of fungi with activities ranging from 78.70 percent to 100 percent on Aspergillus niger and Penicillium notatum. The acetone extracts of the leaves and stem bark were active against A. niger (51.76 percent) and P. notatum (77.22 percent). The aqueous extract of Hippobromus pauciflorus leaves at 50, 100 and 200 mg/kg body weight doses were evaluated for anti-inflammatory, analgesic and antipyretic activities in male Wistar rats. Anti-inflammatory activity was studied by using carrageenan-and histamine induced oedema right hind paw volume while the analgesic effect was evaluated using formalin-induced pain and tail flick nociception response. The brewer’s yeast-induced pyrexia model was used for the antipyretic investigation. The extract at all the doses used significantly inhibited both the carrageenan- and histamine-induced inflammation in a manner that was not dose dependent. The extract reduced the formalin-induced pain licking as well as prolonged the reaction time in the tail flick-induced pain. The effects of the aqueous extract of the plant leaves at 50, 100 and 200 mg/kg body weight doses were investigated for 14 days on some biochemical parameters of male Wistar rats. The extract at all the doses tested did not significantly alter the levels of white blood cells, red blood cells, mean corpuscular volume, platelets, neutrophils, monocytes, lymphocytes and large unstained cells. While the levels of haemoglobin, packed cell volume and basophils increased at specific doses, those of mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and eosinophils decreased. In vitro antiviral activities of the plant against herpes simplex virus type 1(HSV-1) and coxsakie virus B6 were investigated. Cytotoxicity was evaluated by MTT assay in Vero cells. At concentrations ranging from 165-270/μg/ml there was significant antiviral activity against HSV-1, but toxicity was also noted. There was no antiviral activity against coxsakie virus B6. Bioactivity-guided fractionation of the leaves of H. pauciflorus yielded three known compounds. From the ethyl acetate fraction, two compounds were isolated (epicatechin and -sitosterol ) and from the n- hexane fractions, one compound (lupeol) was isolated. They were isolated and identified using various techniques. The antimicrobial, anti-inflammatory, analgesic and anti-pyretic activity of these compounds have been reported in literature. The structure and distribution of foliar appendages on the leaves of H. pauciflorus were examined by scanning electron microscope. The leaves have long unicellular nonglandular trichomes which were distributed over the mid rib and densely populated at the edges of the adaxial and abaxial surfaces. In general, the experiments and tests conducted in this study appear to have justified the use of Hippobromus pauciflorus for the treatment of eye infections and make a substantial contribution to the knowledge base of the use of herbal medicine for the treatment of the eye infections.
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Date Issued: 2010

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Structural, optical and electrical characterization of nano-sized c-tio2 quamtum dots synthesized by spray pyrolysis

- Taziwa, Raymond Tichaona

Authors: Taziwa, Raymond Tichaona
Date: 2014
Language: English
Type: Thesis , Doctoral , PhD (Chemistry)
Identifier: vital:11342 , http://hdl.handle.net/10353/d1016089
Description: In the 21st century, scientific communities face challenges and opportunities concerning future development, where innovations must be a key driver over the past, evolution of African societies were based on incomplete models, only taking into account economical growth and not paying attention to environmental deterioration as a consequence of anthropogenic activity and environmental pollution. We have to learn from our past mistakes in order not to repeat them. Education and research of today as the embryonic stages of the development models of tomorrow should be directed toward a sustainable mentality. In this sense, solar energy technologies have emerged as key instruments for minimizing environmental impact as well as reducing economic cost in the field of renewable energies. Titanium dioxide is a fascinating low cost material exhibiting unique properties of stability and photo catalytic activities, leading to clean technologies in water purification and energy conversion of sunlight. However, conventional techniques (high temperature, high vacuum, high pressures) of processing titanium dioxide are a technological limitation due to excessive energy consumption. This poses a handicap for practical applications in areas such as preparation of hybrid organic/Titanium dioxide materials or devices on thermo flexible substrates such as plastic material. It is for this reason that the investigation presented in this Ph.D thesis deals with the development of spray pyrolysis techniques for preparation of carbon doped titanium dioxide nano powders for solar cell applications. This thesis is therefore structured as follows: Chapter 1 gives a general overview of the work done in this thesis. This work relies greatly on the excellent structural optical and electrical properties of TiO2 thin films, as well as its chemical resistance and insulating properties. A summary of the physical, optical, electrical and chemical properties reported in the literature, with an emphasis on those relevant to solar cell fabrication, is presented in Chapter 2. Chapter 3 gives a concise literature review on models governing droplet formation in ultrasonic spray pyrolysis (USP) techniques, the limitations of these models have been exposed and a new relation model for estimating the final particle size given a set of initial reaction conditions has been proposed. The presently derived model is quite advantageous in that it does not require the investigator to look up values of surface tension and density for every precursor solution. Chapter 4 presents in detail the designed and constructed spray pyrolysis system capable of realizing desired nano structures for photovoltaic applications. The first system employed an ultrasonic atomization spray nozzle in order to create an aerosol of the TiO2 precursor. The reasons for choosing ultrasonic spray deposition (USP) and the TiO2 precursors, titanium iso propoxide and titanium tetra butoxide are discussed. Chapter 5 outlines experimental methodologies used in synthesis and characterization of the materials used in this study. Chapter 5 further provides experimental methodologies used in fabrication of a new type of photo electrochemical solar cells (PECs). Chapter 6 reveals the opto-electrical results of PECs solar cells fabricated. There are numerous properties that are affected by the size but emphasis will be placed on nano-size and confinement effects. Chapter 7 presents a confirmation of the phonon confinement effects in C-TiO2 QDs for the first time. In addition Chapter 7 also presents a new phonon confinement model. Chapter 8 reveals the optical, structural and electronic properties of C-TiO2 QDs synthesized by USP and PSP techniques. In addition the electrical properties of C-TiO2 QDs PEC solar cells devices are reported in Chapter 8. Concluding remarks, with potential future research projects are presented in Chapter 9. Through these 9 chapters, all research questions have been answered satisfactorily and all objectives met. Most of the work contained in this thesis has been subjected to external reviews through publication of these peer reviewed articles.
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Date Issued: 2014

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Land Use Planning: ALP 418 / ALP 419

- Monde, N, Meikle, G, Trollip, I R F, Brutsch, M O, Muchaonyerwa, P, Owusu-Aduomi, O K, Laker, M C

Authors: Monde, N , Meikle, G , Trollip, I R F , Brutsch, M O , Muchaonyerwa, P , Owusu-Aduomi, O K , Laker, M C
Date: 2010-07
Language: English
Type: Examination paper
Identifier: vital:17694 , http://hdl.handle.net/10353/d1010095
Description: Land Use Planning: ALP 418 / ALP 419, Supplementary examination July 2010.
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Date Issued: 2010-07

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Assessment of the effects of stream channel incision on soil water levels, soil morphology and vegetation in a wetland in the Hogsback area, Eastern Cape, South Africa

- Omar, Mohamed Yussuf

Authors: Omar, Mohamed Yussuf
Date: 2015
Subjects: Hydrology Wetland Soil Formation
Language: English
Type: Thesis , Masters , Degree
Identifier: http://hdl.handle.net/10353/3132 , vital:28264
Description: Wetland degradation in the form of channel incisioning can significantly alter the hydrological functioning of a wetland. In this study in a small headwater wetland in the Hogsback area, Eastern Cape Province, the impact of channel incisioning on soil water levels and soil morphology was examined. A good correlation (R2 = 0.89) exists between the depth of channel incisioning and average water table depths in most of the 21 installed piezometers. In localised cases the upslope supply of water was in equilibrium with drainage from the piezometers. Although all the studied soils show hydromorphic characteristics, those continuously saturated close to the surface exhibit redox accumulations in oxygen supplying macropores, whereas gleyic colour patterns occur deeper in soils where the water table has been lowered by channel incision. The nature and occurrence of different hydromorphic soil indicators observed confirm the contribution of soil morphology as a valuable indicator of long-term average soil water conditions. The study evaluates the effects of hydrological processes on plant species composition and distribution in a Hogsback wetland. Twenty-four circular plots with a radius of 2 m were established between March and August 2013. Within each sample plot, the habitat information and species present were recorded including Braun-Blanquet cover-abundance value for each and every species present in the plot. Plant species were identified in the field and the unknown plant species were collected, pressed, oven-dried and identified at the National Herbarium, South African Biodiversity Institute (SANBI), Pretoria and Schonland Herbarium, Rhodes University, Grahamstown. A total of 39 taxa belonging to 19 families and 34 genera were recorded from the Hogsback wetland. Of the documented taxa, three were exotic and three endemic to South Africa, indicating diversity and dynamic nature of Hogsback wetland flora. Plant families with the highest number of species were: Poaceae (11 species), Asteraceae (5 species), Onagraceae and Cyperaceae with 3 taxa each. The low number of exotic plant species in Hogsback wetland (three taxa in total) indicates limited anthropogenic influence. Unique species recorded in Hogsback wetlands are three species that are endemic to South Africa, namely, Alchemilla capensis, Helichrysum rosum and Lysimachia nutans. Five main floristic associations were identified from the Hierarchical Cluster Analysis whilst Detrenched .Correspondence Analysis (DCA) identified four groups. The Canonical Correspondence Analysis (CCA) indicates that edaphic factors, particularly in an area covered with water, erosion category, organic matter content and water table depth were the most important environmental variables measured accounting for the vegetation pattern present in the Hogsback wetland.
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Date Issued: 2015

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Synthesis and structural studies of NiS and PdS nanoparticles/nanocomposites from dithiocarbamates single source precursors

- Nqombolo, Azile

Authors: Nqombolo, Azile
Date: 2016
Language: English
Type: Thesis , Masters , MSc (Chemistry)
Identifier: vital:11359 , http://hdl.handle.net/10353/d1021326
Description: The main aim of this research is to synthesize Ni(II) and Pd(II) dithiocarbamate complexes and use them as single source precursors for the synthesis of NiS and PdS nanoparticles and metal sulphides potato starch nanocomposites. Four dithiocarbamate ligands were synthesized and characterized using elemental analysis and spectroscopic techniques. The ligands were used to prepared homoleptic Ni(II) and Pd(II) complexes of the dithiocarbamate ligands. The metal complexes were characterized with elemental analysis, UV-Vis, FTIR and 1H-NMR spectroscopic techniques. Conductivity measurements indicate that all the complexes are non-electrolytes in solution and results from the electronic spectra studies confirmed the proposed 4-coordinate square planar geometry around the metal ions. The nickel complexes showed d-d transitions around 477 nm while in the palladium complexes, no d-d transitions were observed but the compounds showed strong metal to ligand charge transfer transitions. From the FTIR spectra studies, it can be confirmed that the complexes were successfully synthesised because all peaks of interest were observed at expected regions from the literature. The νC-N was observed around 1469-1495 cm-1, νC=S around 1101-1188 cm-1 and νC-S around 738-1060 cm-1 for both Ni(II) and Pd(II) complexes. νNi-S was observed around 375-543 cm-1 and νPd-S around 529-545 cm-1. The FTIR also confirmed that the dithiocarbamate ligands act as bidentate chelating ligands through the sulfur atoms. The complexes were used as single source precursors and thermolysed in hexadecylamine (HDA) at 220 °C to prepare four HDA-capped nickel sulfide nanoparticles and four palladium sulfide nanoparticles. The as-prepared nanoparticles were studied with optical absorption spectra, photoluminescence, powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The optical studies results showed that NiS have large band gaps that are greater than that of the bulk, therefore they are found to be blue shifted relative to the bulk, which shows that they have small particle size and thus confirming their quantum confinement effect. PL spectra reveal that the emission peaks are red shifted compared to the absorption band edges of the nanoparticles. The XRD patterns confirmed the formation of cubic and rhombohedral phase for NiS nanoparticles and cubic phase for PdS nanoparticles. SEM images of both NiS and PdS show uniform surface morphology at low and high magnification with different shapes. EDS analyses confirmed the presence of Ni, S, and Pd in each of the spectrum indicating that the nanoparticles were successfully synthesized. TEM images showed that the synthesised nanoparticles have uniform and narrow size distribution with no agglomeration. The sizes of the NiS nanoparticles were found to be in the range of 12-38 nm for NiS1, 8-11 nm for NiS2, 9-16 nm for NiS3 and 4-9 nm for NiS4. The TEM images for the as-prepared PdS nanoparticles showed that the average crystallite sizes are 6.94-9.62 nm for PdS1, 8-11 nm for PdS2, 9-16 nm for PdS3 and 4-9 nm for PdS4 respectively. The nanoparticles were used to prepare potato starch nanocomposites and SEM images indicate that the surface morphology of starch polymer nanocomposites compose of potato starch and few particles in between the pores of the matrix, this is due to the small ratio of nanoparticles used.
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Date Issued: 2016

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Antibacterial and phytochemical studies of selected South African honeys on clinical isolates of Helicobacter pylori

- Manyi-Loh, Christy E

Authors: Manyi-Loh, Christy E
Date: 2012
Subjects: Helicobacter pylori , Honey--South Africa , Drug resistance in microorganisms , Bacterial diseases , Honey -- Therapeutic use , Helicobacter pylori infections , Traditional medicine -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Doctoral , PhD (Microbiology)
Identifier: vital:11240 , http://hdl.handle.net/10353/d1001056 , Helicobacter pylori , Honey--South Africa , Drug resistance in microorganisms , Bacterial diseases , Honey -- Therapeutic use , Helicobacter pylori infections , Traditional medicine -- South Africa -- Eastern Cape
Description: Infection with Helicobacter pylori has been associated with the pathogenesis of numerous stomach and gastroduodenal diseases that pose threats to public health. Eradicaftion of this pathogen is a global challenge due to its alarming rate of multidrug resistance. Consequently, to find an alternative treatment, the search is increasingly focused on new antimicrobial product from natural sources including honey. Honey has been used as medicine in several cultures since ancient time due to its enormous biomedical activities. Its beneficial qualities have been endorsed to its antimicrobial, antioxidant, anti-inflammatory properties added to its phytocomponents. In this study, the anti-H. pylori activity of South African honeys and their solvent extracts as well as the phytochemicals present in the two most active honeys were evaluated. Agar well diffusion test was used to investigate the antimicrobial activity of six honey varieties obtained from different locations in the country. Subsequently, the honeys were extracted with four organic solvents viz n-hexane, diethyl ether, chloroform and ethyl acetate employed in order of increasing polarity. The antibacterial activity of the different solvent extracts of each honey was evaluated by agar well diffusion; broth micro dilution and time kill assays. Different chromatographic techniques (Thin layer & column chromatography) were employed to enumerate the phytochemical constituents in the most active solvent extracts of Pure Honey (PH) and Champagne Royal Train (CRT); and were identified by gas-chromatography linked mass-spectrometry. Linalool pure compound was equally evaluated for anti-H. pylori activity in a bid to trace the antibacterial agent among the variety of compounds identified. Data were analyzed by One-way ANOVA test at 95% confidence interval. Crude honeys and their solvent extracts demonstrated potent anti-H. pylori activity with zone diameter that ranged from [16.0mm (crude) to 22.2mm (extract)] and percentage susceptibilities of test isolates between 73.3% (crude) and 93.3% (extract). The chloroform extracts of PH and CRT were most active with MIC50 in the ranges 0.01- viii 10%v/v and 0.625-10%v/v respectively, not significantly different from amoxicillin (P> 0.05); and efficient bactericidal activity (100% bacterial cells killed) at 1/2MIC and 4xMIC over different time intervals, 36-72hrs and 18-72hrs respectively. The appearance of bands on the thin layer chromatography (TLC) chromatogram spotted with the chloroform extracts of PH and CRT; and developed with hexane: ethyl acetate: acetic acid (HEA) and methanol: acetic acid: water (MAAW) solvent systems indicated the presence of compounds. Purification of the compounds contained in these extracts over silica gel column yielded numerous fractions which were evaluated for antibacterial activity and purity. PHF5 was the most active fraction with a mean MIC50 value of 1.25mg/mL. Volatile compounds belonging to different known chemical families in honey were identified in all the active fractions obtained from PH. Conversely, only four compounds were identified in the active fractions obtained from CRT hence the non volatile constituents could be of prime relevance with respect to antibacterial activity of this honey. Of novelty was the presence of thiophene and N-methyl-D3-azirdine compounds, essential precursors used for the synthesis of natural products and pharmaceuticals with vital biomedical properties. Linalool demonstrated potent inhibitory (MIC95, 0.002- 0.0313mg/mL) and bactericidal activity (0.0039-0.313mg/mL) against the test isolates. On the other hand, a significant difference was recorded (P < 0.05) in comparing the activity of linalool compound to the fractions. PH could serve as a good economic source of bioactive compounds which could be employed as template for the synthesis of novel anti-H. pylori drugs. However, further studies are needed to determine the non volatile active ingredients in PH and CRT as well as toxicological testing
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Date Issued: 2012

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Impact of Agricultural development projects on poverty alleviation In Amajuba district municipality (KZN)

- Mabaso, Siphesihle Merit

Authors: Mabaso, Siphesihle Merit
Date: 2014
Subjects: Poverty -- South Africa -- KwaZulu-Natal , Agricultural development projects , Poor -- Services for -- South Africa -- KwaZulu-Natal
Language: English
Type: Thesis , Masters , MSc Agric (Agricultural Economics)
Identifier: vital:11217 , http://hdl.handle.net/10353/d1019770 , Poverty -- South Africa -- KwaZulu-Natal , Agricultural development projects , Poor -- Services for -- South Africa -- KwaZulu-Natal
Description: The study determined the impact of agricultural development projects on poverty alleviation at Amajuba district municipality. Data was drawn from 100 respondents, projects were purposively selected in line with the focus of projects members and non-projects members in Dannhauser under Amajuba District municipality to access and investigate the impact of agricultural development projects on poverty alleviation. The study presents the results of assessing those that are in groups and those that are working individually on agricultural production to alleviate poverty. The data was captured using a questionnaire which was administered through face-to-face interviews. Descriptive statistics and binary logistic regression model were used to analyse and compare the level of livelihood and variables between project and non-project members. The results show that project members are more productive than non-project members. Project members had more access to funding, training, markets and extension services compared to non-members. However, the results further showed that being a project member attracts some rewards which end up improving the living standards as well as alleviates the poverty levels of farmers, whereas working as an individual limits the farmer(s) from receiving reasonable government assistance such as funding and extension services delivery. The descriptive results indicated that members of most rural households were relatively old, married, literate but unemployed. Non-project members were dependent on remittances, social grants and pension funds because the farming strategy could not meet all their household needs. However, The major crops that were grown for income and food security to maintain their livelihoods include: maize, potatoes, onions, butternut, carrots, cabbage and dry beans. Factors that had significant influences on outcomes were extension services, grants, pension and remittances, land productivity, market accessibility, output difference and livelihood. The available opportunities for project members were access to land, funding, markets, infrastructure, inputs and support services from government institutions, as well as NGO’s.
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Date Issued: 2014

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Farmers` perceptions of livestock feeding and rangeland management: dynamics of soil, forage and cattle blood serum mineral levels in two communal areas of the Eastern Cape, South Africa

- Gwelo, Farai Alice

Authors: Gwelo, Farai Alice
Date: 2012
Subjects: Range management -- South Africa -- Eastern Cape , Animal feeding -- South Africa -- Eastern Cape , Livestock -- Breeding -- South Africa -- Eastern Cape , Communal rangelands -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MSc Agric (Pasture Science)
Identifier: vital:11581 , http://hdl.handle.net/10353/d1006785 , Range management -- South Africa -- Eastern Cape , Animal feeding -- South Africa -- Eastern Cape , Livestock -- Breeding -- South Africa -- Eastern Cape , Communal rangelands -- South Africa -- Eastern Cape
Description: This study was conducted to determine livestock production, rangeland management and the mineral levels of soils, grass and cattle blood serum in two communal areas (Kwezana and Dikidikana). A total of 77 farmers from both Kwezana and Dikidikana were interviewed to determine farmers’ perceptions. Soil and grass sampling was done at three sites in each communal area. Soil and grass samples were analysed for N, Ca, Mg, K, P, Fe, Cu, Zn, Mn and Bo. Three, two and half year old Nguni heifers were randomly selected from each communal area and blood samples were collected for the analysis of Ca, Mg, K, Cu and Fe. Soil, grass and blood samples were all collected in two seasons (winter and summer). The results of the study revealed that feed availability was the major constraint in livestock production as indicated by 83 percent of thefarmers at Kwezana and 88 percent at Dikidikana. At both villages less than 20 percent practiced supplementation and grazing management. From both villages, 83 percent of the farmers did not know the forage species preferred by their cattle. The second study revealed significant seasonal variations in soil N in both study areas while forage N exhibited seasonal variations (P<0.05) only at Dikidikana. Spatial variation (P<0.05) in soil Mn was apparent in both seasons at Dikidikana and in summer at Kwezana. At Dikidikana forage P varied (P<0.05) both seasonally and spatially. In both study areas, there was a positive correlation (P<0.05) between soil and forage levels of Cu and Zn. The blood serum of animals from both study areas had higher (P<0.05) K and Na in winter than in summer. Farmers do not understand the composition of their rangelands but are concerned about cattle nutrition during winter. Indeed the mineral status of soils, forages and Nguni cattle blood serum tend to vary not only seasonally but also spatially. There is need therefore to assist the farmers to understand these changes in order to find ways of managing the rangelands in a way that will manipulate both seasonal and spatial variations in soil nutrients for the benefit of the grazing livestock. Further research is required to determine the digestibility of the forages and the amount of energy available from these forages for the grazing livestock.
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Date Issued: 2012

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Assessment of the quality indices and prevalence of Escherichia coli pathotypes in selected rivers of Osun state, Southwestern Nigeria

- Titilawo, Osuolale Yinka

Authors: Titilawo, Osuolale Yinka
Date: 2015
Language: English
Type: Thesis , Doctoral , PhD (Microbiology)
Identifier: vital:11295 , http://hdl.handle.net/10353/d1021274
Description: Surface waters are important freshwater sources used for domestic, industrial, agricultural and recreational activities, and the availability of good quality freshwater is indispensable for preventing water-borne diseases and improving quality of life especially in communities that lack pipe-borne water. Water samples were collected from ten rivers at different locations in Osun State, Southwestern Nigeria. A total of 12 physicochemical parameters, counts of total coliforms (TC) and Escherichia coli isolates were determined using standard analytical procedures. Confirmed Escherichia coli isolates (n=300) were assessed for the presence of 10 virulence genes (VGs) associated with Escherichia coli strains causing intestinal and extra-intestinal infections. The recovered Escherichia coli isolates were elucidated for their antibiogram profiling by disk diffusion method and the resistant isolates were further profiled for their genotypic antimicrobial resistance by polymerase chain reaction technique. The physicochemical qualities ranged as follows: pH (6.9 - 7.6), temperature (26 – 29 ºC), turbidity (2.28 – 9.46 NTU), electrical conductivity (229 – 581 μS/cm), nitrate (0.03 – 0.05 mg/L), nitrite (0.00 – 0.01 mg/L), sulphate (3.33 – 20.33 mg/L), chloride ions (7.83 – 27.33 mg/L), dissolved oxygen (4.23 – 5.57 mg/L), total dissolved solids (56 – 184 mg/L), total hardness (78 – 519 mg/L) and alkalinity (50.67 – 146.67 mg/L). Statistical analysis showed that pH, temperature, electrical conductivities, nitrates, nitrites, chloride, dissolved oxygen, total dissolved solid, total hardness and alkalinity were significantly different (P < 0.05), whereas turbidity and sulphate were not significantly different (P ˃ 0.05) from each parameter with respect to sampling sites. While the VG lt for enterotoxigenic E. coli had the highest prevalence of 45%, the enteropathogenic E. coli genes eae and bfp were detected in 6% and 4% of the isolates respectively. The VGs stx1 and stx2 specific for the enterohemorrhagic E. coli pathotypes were equally detected in 7% and 1% of the isolates respectively. Also, the VG eagg harboured by enteroaggregative pathotype and diffusely-adherent E. coli VG daaE were detected in 2% and 4% of the isolates respectively and enteroinvasive E. coli VG ipaH was not detected. In addition, the VGs papC for uropathogenic and ibeA for neonatal meningitis were frequently detected in 19% and 3% of isolates respectively. While all the isolates tested were susceptible to imipenem, meropenem, amikacin and gatilofloxacin, others were variously susceptible, and resistant as follows; ciprofloxacin (96%), kanamycin (95%), neomycin (92%), streptomycin (84%), chloramphenicol (73%), nalidixic acid (66%), nitrofuratoin (64%), gentamycin (63%), doxycycline (58%), cefepime (57%), tetracycline (49%) and cephalothin (42%). Conversely, all the isolates were resistant to sulphamethoxazole, and high levels of resistance were equally observed against amoxycillin (59%), ampicilin (57%) and cefuroxime (40%). Cefepime, cephalothin, cefuroxime, nalidixic acid, nitrofuratoin, chloramphenicol and tetracycline were not significantly different in their effect against the isolates from all locations (P > 0.05), whereas the resistance profile of the isolates against gentamycin, ciprofloxacin, sulphamethoxazole, ampicillin and amoxicillin were significantly different (P < 0.05). Amikacin, kanamycin, streptomycin, meropenem, imipenem and gatilofloxacin were statistically excluded from the analysis since all tested isolates showed total susceptibility to these antimicrobials. The multiple antibiotic resistance indexing ranged from 0.50 to 0.80 for all the sampling locations and exceeded the threshold value of 0.2. Prevalence and distributions of the 19 resistance determinants assessed were obtained as follows; [sulfonamides (sulI (8%), sulII (41%)], [beta-lactams; (ampC 22%; blaTEM, (21%), blaZ (18%),], [tetracyclines (tetA (24%), tetB (23%), tetC (18%), tetD (78%), tetK (15%), tetM, (10%)], [phenicols; (catI (37%), catII (28%), cmlA1 (19%)] and [aminoglycosides; (aacC2 (8%), aphA1 (80%), aphA2 (80%), aadA (79%) and strA (38%)]. The Pearson chi square exact test revealed many strong significant associations among ampC, blaTEM, blaZ and tetA genes with some determinants screened. In the same vein, a grand total of 366 resistance gene fingerprints were spotted across the sampling locations and among the resistant pathotypes, the modal prevalent gene prints were found among the ETEC strains in 148 (40%), being the predominant pathotype observed, followed by UPEC strains 80 (22%) while the lowest was the least occurring EAEC pathotype 14 (4%). While some physicochemical parameters exceeded prescribed standards for drinking water, some fell within. The total coliforms obtained in all the sampling sites were above the acceptable limits. Findings reveal the presence of diarrhoeagenic and non-diarrhoeagenic E. coli in the selected rivers and suggest a potential public health risk as the rivers are important resources for domestic, recreational and livelihood usage by their host communities. The multiple drug resistance indexing signifies isolates and pathotypes of high antimicrobial usage origin. An increase in the antimicrobial resistance signatures towards conventionally used antibiotics as observed in this study necessitates for safe water supply, adequate sanitation facilities and proper surveillance programs towards the monitoring of antimicrobial resistance determinants in water-bodies. Generally, results from this study indicate that the river waters are not suitable for consumption, domestic or recreational use and re-echo the importance of safeguarding the freshwater resources of Southwestern Nigeria.
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Date Issued: 2015

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Implementing a robust, cost effective, e-commerce platform for a disadvantaged community of the Eastern Cape, South Africa

- Njeje, Sicelo Given

Authors: Njeje, Sicelo Given
Date: 2008
Subjects: Computer network architectures -- South Africa -- Design and construction , Rural development -- South Africa -- Eastern Cape , Internet marketing , Business enterprises -- Computer networks , Electronic commerce
Language: English
Type: Thesis , Masters , MSc (Computer Science)
Identifier: vital:11373 , http://hdl.handle.net/10353/75 , Computer network architectures -- South Africa -- Design and construction , Rural development -- South Africa -- Eastern Cape , Internet marketing , Business enterprises -- Computer networks , Electronic commerce
Description: The development of electronic commerce (e-commerce) is the most visible business use of the World Wide Web. The primary goal of an e-commerce site is to sell goods and services online. This project deals with developing an e-commerce platform for marginalized communities of the Eastern Cape region, South Africa. An online “shopping mall” to support the marketing of art and crafts from disadvantaged communities is presented, with Linux-Apache-MySQL-PHP (LAMP) as the development environment. Free and Open Source Software has been chosen to develop the virtual shopping mall system because the use of Open Source allows easy localization and extensions to the system developed and long term sustainability, as the source code is available. Also, it might start a “virtuous” circle, whereby young members of the communities hosting art and craft makers become involved in maintenance, and then production, of software systems. One important design constraint from the e-commerce platform presented in this thesis is the possibility for the art and craft makers to manage their shops directly, from the initial loading of their wares to the day-to-day maintenance, such as changes of price or items. The user requirement elicitation and initial field testing were conducted in Dwesa, an area on the wild coast, South Africa. The system currently comprising two shops is live at the time of writing this thesis at www.dwesa.com.
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Date Issued: 2008

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