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Development of a Mobile-Based Livestock Breeding Management System for Communal Farmers in Eastern Cape, South Africa

  • Authors: Aduradola, Oluwatobi John
  • Date: 2021-05
  • Subjects: Mobile communication systems , Mobile computing
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20600 , vital:46364
  • Description: More than a decade ago, South Africa realized the significance of Information and Communication Technology (ICT) and its use in delivering several services; there are still several challenges that block implementing an ICT-based system to deliver services and information better. Since communal development is still one of the country's biggest concerns, ICT is among several advances and views recognized for speeding up communal development and providing for the country's economic growth. This research aimed to investigate and implement ICT tools for communal farmers in the context of information needs and information dissemination. The research concentrated on the technical tools and skills needed to implement an ICT tool for communal farmers and other stakeholders. A prototyping methodology was used in this research in the development of the required prototype. A study was then conducted to understand the present state and the information needs of communal farmers where the questionnaire was administered. The research results demonstrated the critical need for communal farmers to get information timely at their convenience. A mobile database system was then designed and developed that suits communal farmers' nature. This system was an offline android application that assists with their information need and its dissemination, and it allows the sharing of the communal farmer's data to other stakeholders. , Thesis (MSc) (Computer Science)-- University of Fort Hare, 2021
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  • Date Issued: 2021-05

Modelling internet network intrusion detection in smart city ecosystems

  • Authors: Mfenguza, Wandisa
  • Date: 2021-05
  • Subjects: Ecosystem management , Smart cities
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/22501 , vital:52382
  • Description: Smart city systems are intended to enhance the lives of citizens through the design of systems that promote resource efficiency and the real-time provisioning of resources in cities. The benefits offered by smart cities include the use of internet of things (IoT) sensors to gather useful data such as power demand to inhibit blackouts and the average speed of vehicles to alleviate traffic congestion. Nonetheless, earlier studies have indicated a substantial increase in cyber-security issues due to the increase in the deployment of smart city ecosystems. Consequently, IoT cyber-security is recognised as an area that requires crucial scrutiny. This study begins by investigating the current state of intrusion detection in smart city ecosystems. Current intrusion detection frameworks lack the capability to operate under extremely limiting settings such as conditions of low processing power and fast response times. Moreover, the study also identifies that, despite intrusion detection being a highly researched thematic area, a plethora of previous studies tend to propose intrusion detection frameworks that are more suitable for traditional computer networks rather than wireless sensor networks (WSNs) which consist of heterogeneous settings with diverse devices and communication protocols. Subsequently, this study developed two candidate deep learning models, namely a convolutional neural network (CNN) and a long short-term memory (LSTM) network and presents evidence on their robustness and predictive power. Results have indicated that, unlike the CNN model, the LSTM model can quickly converge and offer high predictive power without the vigorous application of regularisation techniques. The proposed LSTM classification model obtained a remarkable 100% in detection rates and further reported 0% in false alarm and false negative rates. This study gives a broad overview of the current state of intrusion detection mechanisms for smart city ecosystems to guide future studies. The study also demonstrates that existing intrusion detection systems (IDSs) can be enhanced through the development of more robust and lightweight models that offer high detection rates and minimal false alarm rates to prevent security risks in smart city ecosystems to ensure sustainable and safe smart cities. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-05

Sedimentology, reservoir properties and hydrocarbon potential of the southern Bredasdorp Basin, offshore of the Western Cape Province, South Africa

  • Authors: Baiyegunhi, Temitope Love
  • Date: 2021-05
  • Subjects: Sediments (Geology) , Hydrocarbon reservoirs
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/20753 , vital:46546
  • Description: The Bredasdorp Basin has become the focus for exploration activity (i.e., seismic exploration and drilling) since the discovery of gas-condensate and oil reservoirs in the early 1980s. The basin has proven hydrocarbon reserves and potential for future discoveries. However, uncertainty about the sedimentological and petrographic characteristics, reservoir qualities, thermal maturity and hydrocarbon potential of the source/reservoir rocks has hindered further exploration, particularly in the southern part of the basin. To date, this part of the basin remains unexplored and partially understood with respect to petroleum systems evolution when compared to the central and northern parts of the basin. To fill the research gaps, exploration wells E-AH1, E-AJ1, E-BA1, E-BB1 and E-D3 were investigated so as to unravel the petrographic characteristics, depositional processes and paleoenvironment, tectonic provenance, paleoweathering, hydrocarbon potential, thermal maturity, diagenetic characterisitcs and reservoir qualities of the southern Bredasdorp Basin. The grain size textural parameters revealed that the southern Bredasdorp Basin sandstones are unimodal, predominantly fine-grained, moderately well sorted, mesokurtic and near-symmetrical. The bivariate plots of grain size textural parameters indicate that the depositional environments had been influenced mainly by river/beach/coastal dune conditions. The linear discriminate functions (LDF) diagrams show that the sediments are turbidity current deposits in a shallow marine environment. The Passega diagram revealed that the studied sandstones were mainly deposited by traction currents and beach process. In addition, the grain size log-probability curves and Passega diagram show the predominance of saltation and suspension modes of sediment transportation. Based on the inter-relationship of the various statistical parameters, it is deduced that the southern Bredasdorp Basin are mainly shallow marine deposits with signature of beach and coastal river processes. Based on the lithofacies analysis of the southern Bredasdorp Basin borehole cores, thirteen lithofacies were identified and grouped into six facies associations (FAs). The facies associations are: matrix supported conglomerate and massive sandstone (FA 1), ripple cross laminated, trough cross bedded and bioturbated sandstone (FA 2), massive sandstone with mudstone and shale interbeds (FA 3), alternating laminated to interbedded sandstone/siltstone and mudstone (FA 4), massive mudstone with minor interlamination of clay-rich sandstones and siltstone (FA 5), and carbonaceous laminated shale and mudstone with occasional siltstone laminae (FA 6). Facies associations FA1, FA2, FA3, FA4, FA5 and FA6 are interpreted as submarine channel-fills, submarine channel-levee, submarine sheet lobe, submarine lobe fring/overflow, basin plain deposits and deep sea floor/basin plain deposits, respectively. Sedimentological evidences from lithofacies interpretation revealed shallow marine environment as the main depositional environment, with minor contribution from the deep marine environment. Petrographic studies show that the southern Bredasdorp Basin sandstones chiefly consist of quartz (52.2–68.0percent), feldspar (10.0–18.0percent), and lithic fragments (5.0–10.2percent). The modal composition analysis revealed that the sandstones could be classified as subarkosic arenite and lithic arkose. The provenance ternary diagrams revealed that the rocks are mainly of continental block provenances (stable shields and basement uplifted areas) and complemented by recycled sands from an associated platform. The tectonic provenance studies show that the sandstones are typically rift-derived arenites and have undergone long-distance transport from the source area along the rift. In the regional context of the evolution of the Bredasdorp Basin, the results suggested that the basin developed on a passive rift setting (trailing edge) of the stable continental margins. The provenance discrimination diagrams based on major oxide geochemistry revealed that the sandstones are mainly of quartzose sedimentary provenance, while the mudrocks are of quartzose sedimentary and intermediate igneous provenances. The discrimination diagrams indicate that the southern Bredasdorp Basin sediments were mostly derived from a cratonic interior or recycled orogen. The bivariate plots of TiO2 versus Ni, TiO2 against Zr and La/Th versus Hf as well as the ternary diagrams of V–Ni–Th×10 suggest that the mudrocks and sandstones were derived from felsic igneous rocks. The tectonic setting discrimination diagrams support passive-active continental margin setting of the provenance. Chemical index of alteration (CIA) indices observed in the sandstones suggest that their source area underwent low to moderate degree of chemical weathering. However, the mudrocks have high CIA indices suggesting that the source area underwent more intense chemical weathering, possibly due to climatic and/or tectonic variations. The organic geochemistry results show that these rocks have total organic carbon, TOC contents ranging from 0.14 to 7.03 wt.percent. The hydrogen index (HI), oxygen index (OI), and hydrocarbon index (S2/S3) values vary between 24–263 mg HC/g TOC, 4–78 mg CO2/g TOC, and 0.01–18 mgHC/mgCO2 TOC, respectively, indicating predominantly Type III and IV kerogen with a minor amount of mixed Type II/III kerogen. The mean vitrinite reflectance values vary from 0.60–1.20percent, indicating that the samples are in the oil-generation window. The Tmax and PI values are consistent with the mean vitrinite reflectance values, indicating that the southern Bredasdorp Basin source rocks have entered the oil window and are considered as effective source rocks in the southern Bredasdorp Basin. The hydrocarbon genetic potential (SP), normalized oil content (NOC) and production index (PI) values all indicate poor to fair hydrocarbon generative potential. The main diagenetic processes that have affected the reservoir quality of the southern Bredasdorp Basin rocks are cementation by authigenic clay, carbonate and silica, growth of authigenic glauconite, dissolution of minerals and load compaction. These aforementioned diagenetic processes act differently in each borehole and at different depths. The influence of cementation and compaction is complex with no particular pattern with increasing depth, suggesting that diagenesis is the main challenge to reservoir characterization in the southern Bredasdorp Basin. The clays in the sandstones act as pore choking cement, which reduces porosity and permeability of the reservoir rocks. Reservoir quality of the sandstones has been improved to various extents due to the development of secondary porosity as a result of partial to complete dissolution of early calcite cement and some detrital grains (feldspars) and also affected by grain fracturing. The scattered plots of porosity and permeability versus cement+clays show good inverse correlations, suggesting that the reservoir quality is mainly controlled by cementation and authigenic clays. Based on the diagenetic study, it can be inferred that the potential reservoir quality of the southern Bredasdorp Basin sandstones is poor-moderate. , Thesis (PhD) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-05

Agro-morphological characterization and investigations into the response of yellow Quality Protein Maize (QPM) genotypes to low soil pH

  • Authors: Bobotyana, Simthandile
  • Date: 2021-04
  • Subjects: Corn as food , Plants--Drought tolerance
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20528 , vital:46087
  • Description: Maize (Zea mays L) is an essential food grain crop in South Africa and is mainly grown under rainfed conditions by small-scale farmers. Quality Protein Maize (QPM) contains a higher level of two essential amino acids, tryptophan, and lysine when equated to normal maize. Therefore, the QPM in communities is a vital cereal where maize is a staple crop. Among the significant abiotic stresses that adversely affect maize productivity, such as soil fertility. Low soil pH or soil acidity results in nutrient deficiencies, as well as the toxicity of minerals such as manganese (Mn), aluminium (Al), and iron (Fe). The objectives of the study were to: (1) Characterize yellow QPM inbred lines and testcross hybrids for agro-morphological variability under optimum conditions, (2) Determine the response of QPM inbred lines and testcross hybrids to Al toxicity, and (3) Estimate the combining ability of QPM genotypes for the tolerance to Al toxicity. The laboratory assessment for tolerance to Al toxicity revealed a negative relationship between relative root growth RRG and hematoxylin staining; among the inbred lines, the genotype 8Y, 17Y, and 7Y had the highest RRG and net root growth (NRG) values and exhibited the highest tolerance to Al tolerance with the least hematoxylin staining. Inbred lines 12Y, 16Y, 19Y, 2Y, 20Y, 24Y, 30Y, 27Y, 34Y, 4Y, and 11Y were moderately tolerant. On the other hand, inbred lines 13Y, 18Y, and QSY5 had the least RRG were susceptible. Forty-four testcross hybrids were generated by crossing 22 QPM inbred lines with two open-pollinated variety (OPV) testers. These hybrids were evaluated together with five checks for different agronomic traits. The hybrids were planted in the summer season of 2017/18 and 2018/19 under rain-fed conditions 7 x 7 alpha lattice design was used. The significant variations among the genotypes for grain yield and most other agronomic traits under optimum, acidic conditions and across environments on combined analysis of variance. The hybrid was 14Y x NC (3.22 t/ha), followed by QSY5 x NC (3.02 t/ha) showed the highest yielding. The mean plant height was 226.23 cm, with ranges 197.60 to 254.85cm. The number of kernels per ear was 35, with a range from 29.45 to 40.25. Conversely, the mean ear length was 19.30 cm with a range of 17.65 to 20.95 cm, and the mean ear diameter ranged from 13,50 to 16,05 cm. The highest yielding hybrid, according to ranking, was 14Y x NC (2,93t/ha), which was ranked number 3, followed by 3Y x NC (2,83 t/ha), which was ranked number 4. Twenty-two yellow QPM inbred lines were evaluated for agro-morphological characteristics. A randomized complete block design with three replicates was used under acidic and normal soil conditions at two locations. The mean performance of inbred lines for grain yield ranged from 1.6 t/ha to 3.1 t/ha under optimum conditions, whereas it ranged from 1.1.t/ha to 1.7 t/ha under an acidic environment. The highest grain yielding genotypes under the optimum environment were 14Y, 7Y, and QSY5, while, in the acidic environment, the highest yielders were 3Y, QSY5, and 17Y. The lowest grain yielder under the optimum environment was 16Y at 1.5 t/ha, whereas 6Y, 7Y, 8Y, and 29Y were the most moderate yielders under the acidic environment. Grain yield displayed positive and significant (p<0,05) correlation with ear height (0.59), plant height (0.55), leaf length (0.18), number of leaves (0.37), number of ears per plot (0,54), number of kernels per row, number of rows per ear and thousand kernel weight. Combined ANOVA revealed that the environment effect was significant for all traits except the number of rows per ear and the number of ears in both environments. A total of 71 genotypes (22 inbred lines, forty-four single crosses, and five checks) were evaluated using a 7 x 7 alpha lattice design with two replications in combining ability. Across environments, the analysis showed a mean grain yield record of hybrids that ranged from 1.78 t/ha to 3.42 t/ha. Combined analysis showed only about 4 percent of the 44 hybrids had better grain yield than hybrid checks, whereas about 11 percent of the 44 hybrids had higher grain yield than two of the five hybrid checks. The highest yielding hybrid was 14Y x NC followed by QSY5 x NC. The Mid-parent heterosis (MPH) for grain yield ranged from -32.70 for 11YxObat to 16.50 percent for 14YxNC among the top-yielding genotypes. The highest positive mid-parent heterosis (MPH) for grain yield was observed in hybrid 14YxNC followed by QSY9xNC, QSY5xOBAT, 3YxNC, 13YxNC and 4YxOBAT, while the remaining hybrids exhibited negative estimates. Inbred lines' proportional contributions to the total variances were much higher than the testers for all traits. Whereas the inbred lines' proportional contribution was lower than the interaction of line x tester except on the number of ears which displayed the highest estimates of variances due to SCA effects, significant variation was observed. The GCA effects on grain yield in both environments generally showed no significant difference among inbred lines except for inbred lines such as QSY5 and 34Y but were positive. The selected crosses showed significant SCA effects in a few agronomic yield-related traits in the combined analysis. Among the hybrids, the only crosses that showed significant and positive SCA effects for grain yield were 25YxNC under optimum and 34YxObat under acidic environment. The inbred lines were assessed for tolerance to Al toxicity under laboratory conditions. Overall, the study identified soil acidity tolerant QPM inbred lines with an excellent combining ability for high-yielding QPM test hybrids, grain yield, and related traits. , Thesis (MSc) (Agriculture, Crop Science) -- University of Fort Hare, 2021
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  • Date Issued: 2021-04

Antibiotics combination therapy option for the control of antimicrobial-resistant non-cholera causing Vibrio species recovered from environmental niches of Eastern Cape, South Africa

  • Authors: Ayodele, Oluwakemi Victoria
  • Date: 2021-04
  • Subjects: Drug resistance in microorganisms , Vibrio cholerae
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20396 , vital:45661
  • Description: Increased rate of antibiotic resistance (AR) poses a serious threat with a resultant notion of a possible end of the antibiotics era, making it a problem of concern to public health and a great implication on the world economy and human society. Despite many approaches developed to curb this menace, antibiotics resistance is still a challenge worldwide. This has made the use of combined therapy as one of the options in many cases. This study was conducted to assess antibiotics combination therapy as an option for the control of antimicrobial-resistant non-cholera causing Vibrio species that were recovered from the environment in the Eastern Cape, South Africa. Two hundred and twenty-eight Vibrio species were recovered from the environment in the Province, and these were deposited in the archive of AEMREG. PCR was used to identify target Vibrio species. Disc diffusion method was used to evaluate the antibiotic susceptibility profile of the confirmed isolates against 11 antibiotics commonly used against infections. MIC and MBC were determined using antibiotics (imipenem, tetracycline, and nalidixic acid) that high resistance was discovered. Checkerboard assay was used to carry out antibiotics combination assay, and the FICI was calculated. Rate of kill was also determined using ½ × MIC, 1 × MIC, and 2 × MIC concentrations of the combined antibiotics at 2 hr intervals. One hundred of the isolates were confirmed to be Vibrio parahaemolyticus, 82 were Vibrio vulnificus and 46 were Vibrio fluvialis. Twenty-two (22) percent of the Vibrio parahaemolyticus isolates showed resistance against tetracycline and their resistance against other antimicrobials is as follows; nalidixic acid (16 percent), ampicillin (14 percent), cefotaxime (14 percent), chloramphenicol (12 percent) and amikacin (11 percent). For Vibrio vulnificus, prevalence of resistance was as follows: imipenem (40 percent), tetracycline (22 percent), ampicillin (18 percent), meropenem (15 percent), and chloramphenicol (11 percent). Vibrio fluvialis showed the following resistance profile: nalidixic acid (28 percent), tetracycline (28percent), ampicillin (20 percent), chloramphenicol (15 percent), amikacin (11 percent) and cefotaxime (11 percent). About 38 multiple antibiotic resistance phenotypes (MARP) were recorded in all species that were evaluated. About 23 percent were resistant to over 3 antibiotics used. The multiple antibiotic resistant indices (MARI) ranged between 0.3 and 0.8. MIC and MBC were carried against isolates that were resistant to the two most common antibiotics tested. MIC and MBC were determined in the following order: tetracycline and nalidixic acid at concentrations ranging from 16 μg/ml to 1024 μg/ml for Vibrio parahaemolyticus and 32 μg/ml to 2048 μg/ml for Vibrio fluvialis. Also, the MIC and MBC of imipenem and tetracycline at concentrations ranging from 8 μg/ml to 256 μg/ml for Vibrio vulnificus were determined. Antibiotics combination therapy was carried out and synergistic activity was observed in 3 of the 16 resistant V. parahaemolyticus isolates, 3 of the16 resistant V. vulnificus isolates and 2 of the 13 resistant V. fluvialis isolates. Antagonism was not observed across all the drug combinations. Rate of kill was also determined and at 6 hr exposure time, the highest concentration (2 × MIC) exhibited bactericidal effect across all three Vibrio species. The result derived in this research, therefore, propose that combination therapy is a promising solution to antimicrobial resistance in Vibrio species. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-04

Barriers and reasons for exercise of rural and urban overweight and obese populations in Buffalo City Metropolitan Municipality, Eastern Cape

  • Authors: Mrwebi, Thembani
  • Date: 2021-04
  • Subjects: Obesity--Prevention , Public health--Exercise
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/22522 , vital:52388
  • Description: It is documented that obesity is highly prevalent across rural and urban groups in industrialised and underdeveloped countries. This problem is an alarming issue as community members remain unsure about avoiding risking their health. Various health surveys reveal that obesity has increased among communities in the Buffalo City Metro Municipality in the Eastern Cape, and it has consequently made communities vulnerable to non-communicable diseases. The researcher explored factors and barriers of exercise for rural and urban obese populations in Buffalo City Metropolitan Municipality, Eastern Cape. This study was descriptive and explorative, utilising a questionnaire for gathering information. A purposive sample of 80 members from the two selected communities completed the questionnaire. A factor analysis was performed to identify factors that motivate physical activity and barriers to physical activity. It was discovered that all evaluated members were fully aware of the harmful repercussions of being overweight or obese. Nevertheless, only a tiny percentage of those who took part in the study decided to live a healthier lifestyle because of their obesity. Constructive motivating factors included increasing their self-image, enhancing their wellbeing, and getting highly involved in active and regular exercise. Negative motivators included finding it challenging to fit into old clothes and the worry of developing obesity-related diseases. Respondents noted the following impediments in regular exercises and physical activities; African cultural values, limited operational hours of physical activity facilities, insufficient time, and a lack of enthusiasm. , Thesis (MPhil) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-04

Effect of fire frequency on the recovery of soil invertebrate communities in semi-arid savanna biome of the Eastern Cape, South Africa

  • Authors: Madikana, Ayabulela https://orcid.org/0000-0002-9119-4650
  • Date: 2021-04
  • Subjects: Soil invertebrates , Fire ecology , Arid regions
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/22831 , vital:52946
  • Description: Fires are common in South African savanna habitats, which can disrupt the dynamics of entire invertebrate populations, endangering biodiversity and the environment. The aim of this study was to look at how fire frequency affected invertebrate population dynamics and biodiversity in a 41-year-old fire experiment at the University of Fort Hare research farm in Alice. The experiment had six different levels of burning frequency: no-burn (K), annual burn (B1), biannual burn (B2), triennial burn (B3), quadrennial burn (B4), and sexennial burn (B6). The experimental plots were replicated two times in a randomized complete block design and have been continuously retained since 1980. A ground yellow mustard solution was used to collect earthworms, which were then identified by an earthworm taxonomist. Pitfall traps were used to collect ants and other insects, which were then identified under a microscope. In total, three soil samples were collected from each plot to assess selected soil nutrients, moisture, and pH. The Shannon diversity index, richness, and population of earthworms, ants, and other insects were calculated, and a one-way ANOVA analysis was done to check if the treatments differed significantly. A correlations study was used to look for any influence connected to soil parameters, including the Shannon diversity index, species richness, and density of soil invertebrates. According to our findings, the measured parameters did not show any significant differences in the measured parameters between the different frequency levels. All the plots had two species of earthworm , Proandricus timmianus and Proandricus beddardi except the biennial burn plot, which had all three, the afore mentioned species and one other unidentified species, Proandricus sp. The triennial burn treatment slightly enhanced the insect diversity, richness, and evenness of ant species difference while the diversity, evenness, and richness were lowest in the sexennial burn plot. However, there was no signif difference in population. After B4, the no burn plot had the second largest diversity and species richness, and the third highest species evenness and had a 100 percent species similarity index. The ants were evenly distributed in the no burn plot compared to the other plots, with K having a lower density than the other plots except for B4, K being slightly more diverse than B6, and B1 with a slightly lower diversity than the other plots, and it being the third species rich plot after B2 and B3, followed by the rest of the plots. This study implied that fire frequency has an insignificant impact on invertebrates’ communities in Savanna biomes words.icant , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-04

Evaluation of anti-diabetic activity of selected red marine macro-algae found along South African coastal areas

  • Authors: Bambo, Karabo https://orcid.org/0000-0002-3721-2424
  • Date: 2021-04
  • Subjects: Marine algae , Phytochemicals
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/22533 , vital:52405
  • Description: Marine macro-algae are a good source of potential primary and secondary metabolites. Phytochemicals of the samples were extracted using methanol and water. This study evaluated the phytochemical constituents, antioxidant activity and antidiabetic activity of selected red marine macro-algae sampled from Gqeberha, South Africa. The species collected were identified as Gelidium pristoides, Scinaia furcellata and Portieria tripinita using DNA barcoding. Results showed the presence of several phytochemicals such as saponins, phenols, flavonols, tannins, proanthocyanidins and flavonoids. Methanol was a more effective polyphenol extraction solvent than water. Gelidium pristoides (H2O) was observed to contain the highest phenol and proanthocyanidin content, which correlated to Gelidium pristoides (H2O) having the greatest FRAP and DPPH radical scavenging activity IC50 at 0.227. Portieria tripinita (MeOH) extract had the greatest flavonoid content. Flavonol content was high for Scinaia furcellata while the highest tannin content was observed in both H2O and MeOH extracts of Gelidium pristoides. All the selected marine macro-algae species showed concentration-dependent reducing power. The extract with the highest ABTS scavenging activity was Gelidium pristoides (MeOH) IC50 at 0.227. Portieria tripinita was the only species that showed Nitric oxide scavenging activity, with (H2O) extract showing the highest activity IC50 at 3.052. Only MeOH extracts of Gelidium pristoides and Scinaia furcellata showed very slight α-amylase inhibition, however, all extracts successfully inhibited the activity of α-glucosidase with the exception of the H2O extracts of Scinaia furcellata. All crude extracts of Gelidium pristoides, Scinaia furcellata and Portieria tripinita showed no significant/weak effect on glucose uptake and utilization by C3A cells following 24 hours of treatment, with the exception of the aqueous extracts of Scinaia furcellata at the highest concentration of 100 μg/ml. The in-vitro MTT cytotoxicity assay revealed that only MeOH extracts of Gelidium pristoides and Scinaia furcellata had a 15 significant toxic effect on C3A hepatocytes at concentrations of 100 μg/ml and 25μg/ml, respectively. Portieria tripinita aqueous extract showed cytotoxicity when evaluated using Hoechst 33342/Propidium iodide (PI) dual staining. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-04

Smallholder farmers’ perception in the adoption of in-field rainwater harvesting techniques in Raymond Mhlaba Local Municipality, Eastern Cape, South Africa

  • Authors: Mtyelwa, Chuma https://orcid.org/0000-0002-0696-4340
  • Date: 2021-04
  • Subjects: Farms, Small , Water harvesting
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/21367 , vital:48499
  • Description: Dissemination, adoption and continued use of adopted technologies are key requirements for improved smallholder farmers’ productivity. In an attempt to improve smallholder agricultural production and creating a resilient smallholder agricultural sector, many technologies such as the in-field rainwater harvesting technique (IRWHT) have been put in place. IRWHT has a tremendous potential for improving livelihoods of rural smallholder farmers, thus decreasing their vulnerability to vagaries of climate change. However, though IRWHT was promoted for agricultural crop production improvement, smallholder farmers discontinued its adoption. This study critically assessed the perception of smallholder farmers in Raymond Mhlaba Local Municipality (RMLM) on the use of the in-field rainwater harvesting technique to assess the underlying factors that led to IRWHT dis-adoption. This study adopted a descriptive study design; purposive sampling was used to select a sample of 120 smallholder farmers that initially adopted IRWHT. Data was gathered through a face-to-face interview and with a pre-tested semi-structured questionnaire. Descriptive statistical analysis frequency count, percentages, means and standard deviation were used for quantitative data analysis. The findings revealed that 96percent of smallholder farmers dis-adopted IRWHT after initial adoption. Moreover, IRWHT was dis-adopted 5-8 years post adoption. Critical reasons behind discontinuity include small land size (23percent), lack of reliable water source (18percent), complexity of IRWHT, continual extension support (17percent) and IRWHT taking up much space (13percent), amongst others. This study also revealed that farmers’ perception towards the innovation attributes of IRWHT, in relative advantage over economic returns such as profitability, had an impact on dis-adoption of IRWHT, with a negative farmers’ perception (𝑥̅ = 2.95). Complexity of IRWHT was associated with discontinuity of IRWHT by smallholder farmers in RMLM, with the majority (60percent) of smallholder farmers indicating that IRWHT was labour intensive. Some (39.9percent) stated that implementation of IRWHT was time consuming. Innovation attributes that led to a high rate of initial adoption were relative advantage with better yield (𝑥̅ = 4. 38) and compatibility. Smallholder farmers indicated that IRWHT can be implemented with cheaper and available working tools (𝑥̅ = 3.54). On trialability, smallholder farmers indicated that IRWHT was triable in different seasons and on observability smallholder farmers had a positive perception (𝑥̅ = 3.81) towards observable improved crop yield. Smallholder farmers had a positive perception (𝑥̅ = 4.14) of extension service support during the scaling-up of IRWHT although they indicated that the extension service support had ceased. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-04

Understanding the contribution of Land Use/Cover (LUC) classes on soil erosion and sedimentation using sediment fingerprinting technique and RUSLE in a GIS interface at sub-catchment level

  • Authors: Taeni, Thembalethu (https://orcid.org/ 0000-0001-7662-8652)
  • Date: 2021-04
  • Subjects: Geographic information systems , Soil erosion , River sediments
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20920 , vital:46747
  • Description: Soil erosion by water is the major source of soil degradation in the world, and South Africa (SA) is not an exception particularly in the Free State (FS) Province. In South Africa, the Caledon River Catchment in the FS Province has been identified as one of the regions where soil erosion has been prevalent for decades. Evidence across many parts of the catchment show a widespread of soil erosion and the contaminant flux associated with sediment into river systems and reservoirs; including the Welbedatcht dam and Carthcart-drift dam in Ladybrand. It is of these issues that the current work aimed at enhancing the understanding of sediment sources and soil erosion dynamics at the Caledon River Basin. The objectives of the study were to locate sources of suspended sediments and to assess and quantify the contribution of Land Use Cover (LUC) classes to water erosion and sediment yield at a sub – catchment level of the Caledon River Basin. To achieve the objectives set out for this research, a study was conducted at a sub - catchment level of the Caledon River Basin in the FS Province, South Africa. The sediment–fingerprinting approach and the Revised Universal Soil Loss Equation (RUSLE) model were used in the study under Geographic Information System (GIS) settings. A qualitative and quantitative interpretation of the geochemical data were used to evaluate the potential for distinguishing catchment sediment sources. The application of multivariate sediment mixing models incorporating Monte Carlo simulations was undertaken to investigate recent variations in sediment sources. Lastly, to document the impact of LUC change on soil erosion; data from soil profile database, Landsat 8 OLI–TIRS and climate (i.e. rainfall) were used to assess and map the spatial and temporal pattern changes of soil erosion at a sub – catchment level as related to LUC changes. In this study, the sub–catchment was classified into 6 LUC classes. Thereafter soil erosion was quantified for three consecutive years namely; 2015, 2016 and 2018 using the soil erosion factors as GIS–layers. The investigation of sediment source types and spatial provenance in the catchment showed that the grassland areas have consistently been the main sediment source (83 percent) throughout the study period. Findings further showed that there was an increase in contributions from cultivation and abandoned cultivated fields. Sediment contribution from surface sources was dominant (54 percent) and thereafter, subsurface sediment input increased (62 percent). This trend is indicative of increased severity of gully erosion in the area and thus is consistent with other studies. To comprehend the influence of LUC class modification dynamics on soil erosion, water erosion in particular at the sub-catchment commencing from 2015 to 2018 (4 years), multi-temporal Landsat 8 information jointly with the RUSLE model were used. A post-classification, LUC class alteration comparison revealed that water bodies, shrubs and forested region and grassland declined by 0.27 percent, 15.60 percent, and 37.60 percent, respectively. On the other hand, regions under Bad lands, and bare-soil and built-up regions including agricultural region expanded by 2.22 percent, 5.78 percent, and 45.67 percent respectively, between 2015 to 2018 study period. The average yearly soil loss decreased at the sub-catchment and was 10.23,5.71 and 5.82 t ⋅ ha -1 ⋅ yr-1 for 2015, 2016 and 2018 respectively. Although soil loss lessened for the duration of the perceived period, a closer scrutiny revealed that there were nonetheless seeming signs of persistent escalation in soil loss risk. These signs were mostly shown in the elevated parts of the sub-catchment as shown by the red regions on the soil loss map. Additional examination of soil loss findings by LUC classes categories further indicated that most LUC classes categories, including Bare-soil and built-up area, agricultural-land, grassland, and region under shrubs and forests, showed increased soil loss levels during the 4 years’ study period at the sub-catchment. The information on the comparative vividness of diverse sediment sources given by the study must be observed as a noteworthy development towards an understanding of the sediment source dynamics in agricultural river based catchments; more so of the Caledon River Basin. Further research is recommended for other erosion prone catchments in South Africa to identify additional evidence of the spatial and temporal variations in soil erosion and sediment sources. The results of the study suggest that the procedure of assimilating the GIS and RS with the RUSLE model is not just precise, time-efficient and exact in recognizing soil erosion susceptible regions in geospatial and temporal standings. However, it is a cost-efficient substitute to standard field-founded approaches. , Thesis (MSc) (Soil Science) -- University of Fort Hare, 2021
  • Full Text:
  • Date Issued: 2021-04

An Updated Catalogue and Review of Afrotherian (Afroplacentalia) Mammals in the Amathole Museum Collection, Eastern Cape Province, South Africa

  • Authors: Mahala, Buyiswa
  • Date: 2021-03
  • Subjects: Mammals
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20741 , vital:46513
  • Description: The Mammalogy Collection of the Amathole Museum is one of the most comprehensive mammal collections in Africa, with a specialisation in southern African fauna. It was accumulated over almost 100 years, in some instances from areas that no longer support sustainable populations of wildlife. The collection, therefore, is irreplaceable. A museum collection is only as good as its accessibility to students and researchers for it to perform its functions as a biodiversity archive. Accessibility, in turn, depends on up-to-date taxonomy and classification; good curation practices; public awareness of the collection; and electronic access to the details of the collection’s composition. The higher-level taxonomy of the Class Mammalia has undergone extensive changes since the adoption of molecular systematic techniques. Phylogenetic reconstructions based on large DNA sequence databases consistently group placental mammals into four superorders: Laurasiatheria (carnivores, bats, ungulates, whales); Euarchontoglires, a super-clade that includes primates (apes, monkeys and allies), rodents (mouse, rat and guinea pig), lagomorphs, (rabbit and hares), dermopterans (flying lemurs or colugos) and scandentians (tree shrew); Xenarthra (armadillos, anteaters, sloths), and Afrotheria (elephants, sea cows, tenrecs, aardvarks, sengis, golden moles, hyraxes). New relationships have been recognised that have required the erection of new taxonomic groups. Most of the Amathole Museum mammal collection was assembled and accessioned long before this new system was devised, and I undertook this project to begin the re-organisation of the collection according to the new information. I conducted and audit and inventory of all specimens of Afrotheria, or the mammals of African origin, housed in the Amathole Museum collection. I photographed the specimens and corrected and updated their taxonomic details. As we now live in an age of digital information, natural history collections need to be available online to extend public access. Specimen details were entered into Excel files, and their localities were mapped. This kind of information has the possibility of transforming biological curricula to include more authentic and inquiry-driven educational experiences. My future goals are to acquire Malagasy tenrecs for the Amathole Afrotheria collection, and to investigate the taxonomic validity of the Amathole hyrax collection, as many specimens were found with confusing and out-of-date classifications. , Thesis (MSc) (Zoology) -- University of Fort Hare, 2021
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  • Date Issued: 2021-03

Assessing the invasive status and reproductive ecology of two Crataegus species in South Africa; Crataegus monogyna Jacq and C. mexicana DC

  • Authors: Tshilingalinga, Sydney
  • Date: 2021-03
  • Subjects: Crataegus monogyna , Nonindigenous pests , Biological invasions
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20904 , vital:46740
  • Description: In South Africa different species, from the genus Crataegus, including Crataegus monogyna Jacq and C. mexicana DC have been introduced for various reasons in the past. Populations of these plants have now established in multiple provinces. However, the invasive status, risk and insect pollinators that promote their reproduction and dispersal have never been studied in South Africa. This study was aimed at 1) Assessing the risk of, and mapping two Crataegus species, Crataegus monogyna Jacq and C. mexicana DC in South Africa, 2) Determining the role and effectiveness of insects pollinators to fruiting of C. monogyna and C. mexicana, 3) Identifying flower visitors of C. monogyna and C. mexicana, and 4) documenting potential dispersal vectors for both species in the Eastern Cape Province. A framework entitled “Framework and guideline for conducting risk analysis under NEM: BA Alien and Invasive Species Regulation of 2014” was used to assess the risk of the two Crataegus spp, and we conducted field trips to various provinces in SA to map their distribution. The author conducted an exclusion experiment to determine the role and effectiveness of insect pollinators. Observations were conducted to identify flower visitors and potential dispersal vectors for both species. The risk analysis results suggested that both species pose a high risk of becoming invasive in South Africa. The eradication feasibility of both species was found to be medium with C. monogyna having an eradication feasibility score of 5 and C. mexicana having an eradication feasibility score of 4. This meant that there was a 50 percent chance for both species to be eradicated in South Africa currently. After a thorough risk analysis, it was recommended that both species be listed under category 1b on the National Environmental Management Biodiversity Act. Category 1b species are invasive species that need to be controlled, and if possible, they must be eradicated, trading of species from this category is not allowed. Crataegus mexicana was found to be widespread in South Africa with ten relatively small populations distributed in 5 provinces; Limpopo, Mpumalanga, KwaZulu-Natal, Free State and Eastern Cape Province. Crataegus monogyna was found not to be widespread in South Africa, with only three populations found in the Eastern Cape Province. Insect pollinators contribute to the fruiting of both species in SA. However, the exotic plants were also observed to be able to self-pollinate when insects are excluded. Flowers of C. monogyna were visited by various insect species from orders Lepidoptera, Hymenoptera, Coleoptera and Diptera, while C. mexicana is visited by species from the order Hymenoptera, Diptera, Lepidoptera and Coleoptera. Seventy-seven percent (77 percent) of potential dispersal vectors observed for C. monogyna were birds, and 15 percent were mammals. For C. mexicana, 71 percent of potential dispersal vectors observed were mammals, and 29 percent were birds. Crataegus monogyna and C. mexicana are emerging invasive alien species in South Africa, and not much is known about them. Although the two species are listed as invasive weeds in South Africa, very little is known about their invasive status in other parts of the world. This study has managed to give baseline information and data about both species which are already in South Africa. The baseline information and data include the population structure of both species, their distribution, the risk they pose to South Africa biodiversity and their reproduction ecology. Currently, there are no management plans in place for both species in South Africa, and this is because they are not listed yet in the National Environmental Management Biodiversity Act of South Africa. However, this study recommends that current populations continue to be monitored, awareness of both species in various provinces be initiated to help in the discovery of new and emerging populations, and management options of large populations developed in the future. , Thesis (MSc) (Entomology) -- University of Fort Hare, 2021
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  • Date Issued: 2021-03

Production performance, socioeconomic benefits, and agricultural extension services support of scavenging chicken farmers in Raymond Mhlaba Local Municipality, Eastern Cape Province

  • Authors: Fentele, Ziphozethu https://orcid.org/ 0000-0001-7939-2964
  • Date: 2021-03
  • Subjects: Broilers (Chickens) , Poultry -- Breeding
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/21490 , vital:48751
  • Description: Scavenging chicken production plays a significant role in the lives of rural farmers as it ensures food security by providing eggs and meat to rural farmers almost in all developing nations. Rural farmers not only consume scavenging chickens, they also sell live chickens to customers to generate immediate income and are able to acquire other products using the money from the sales. The purpose of this study was to investigate production performance, socioeconomic benefits, and agricultural extension services support for scavenging chicken producers. The study was carried out in eight villages in Raymond Mhlaba Local Municipality in the Eastern Cape Province of South Africa. This study employed the multistage sampling technique for data collection from respondents between October and November 2018. The study used descriptive statistics, frequencies, percentages and multiple linear regression models to analyse quantitative data that was collected from a survey of 161 rural farmers that rear scavenging chickens. The results reveal that the majority (68.3percent) of the respondents in Raymond Mhlaba Local Municipality were women, while 52percent were married. Forty-eight percent of the respondents had attained high school education. The majority (53.4percent) relied on social grants and a further majority (68.3percent) had 1 to 10 years of experience in scavenging chicken production. The majority (84.5percent) of the households had between 1 and 50 chickens, with an overwhelming majority (95percent) practising free range system. Most (74.5percent) of the chicken houses were built with scrap material found within the community. The supplementary feed that was mostly offered to scavenging chickens was maize. The majority (95.7percent) of respondents experienced disease outbreaks, the most dominant of which was the Newcastle disease. Most (94.4percent) of the farmers offered a variety of indigenous medicines, mainly Aloe Ferrox. In addition, the majority (88.8percent) of the respondents experienced predation challenges The primary purpose of rearing scavenging chickens was consumption. Chickens were slaughtered for home consumption while forty-two percent at most. Most (50.9percent) of the respondents indicated that they offered chickens as gifts and as friendly gestures. The majority (82.0percent) indicated that they did not use chicken for any cultural rituals. A large (88.2percent) number of the respondents felt food secured as a result of rearing scavenging chickens, as they access products such as eggs and meat. The majority (98.8percent) of the respondents had never received any form of training from agricultural extension services. The results of the multiple linear regression model revealed that independent variables such as number of chickens, type of cockerels, number of hens, type of housing, type of training and cost of trainings had strong statistical significant values (p<0.001) zero-order correlation with production performance,while age and gender had statistical significant values at (p<0.05) and (p<0.010). For the improvement of the production performance of scavenging chicken production of rural farmers, the study recommends massive campaign among the farmers by agricultural extension services to create awareness on the dangers inherent in the use of unorthodox approaches to treating pests and diseases in scavenging chicken. Scavenging chicken farmers could be supported with simple technologies that are affordable on housing, medication and feed supplements. Training should focus on housing, disease management and feeding of scavenging chickens. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-03

Synthesis, characterization and in vitro biological studies of cholesterol-based carriers as potential therapeutic agents

  • Authors: Ruwizhi, Ngonidzashe
  • Date: 2021-03
  • Subjects: Drug delivery systems , Cholesterol
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20708 , vital:46443
  • Description: Malaria, cancer and bacterial infections are numbered among the highest causes of fatalities. Most of the drugs used to combat these diseases suffer from resistance, poor absorption and bioavailability and high toxicity. Therefore, delivering a drug requires an excellent drug delivery system that must provide the medication at the site of action in the minimum time possible. Cholesterol is a sterol that is abundantly found in the human body and forms a part in the structure and organization of cell membranes. Many researchers have used cholesterol, especially in organic synthesis, because of its ready availability, low cost and functional groups that can be readily derivatized. In this research, different therapeutic agents (anticancer, antimalarial and antibacterial) were conjugated to cholesterol, and the synthesized compounds were characterized using FTIR, 1H and 13C NMR, Mass Spectroscopy, 2D 1H-13C, HSQC NMR and tested for in vitro biological activity. Thirteen compounds were successfully synthesized. CHS-Cur was the most effective against all Gram-positive bacterial strains, while CHS-Cur, CHS-ZD and C-CAC-ZD were effective against all the bacterial strains. C-CAC-Pyr showed good antiplasmodial activity with 97.75 and 97.83% inhibition at 20 and 10 μg/ml concentrations, respectively. The biological activity of some of the compounds was increased by the conjugation of cholesterol, while others displayed reduced biological activity. In vitro cytotoxicity of the synthesized compounds on HeLa (cervical cancer) cells showed that compounds 2 (7.559 μg/mL), 3 (5.840 μg/mL), 5 (1.44 mg/mL), 7 (4.308 μg/mL) and 11 (3.295 μg/mL) exhibited some good anticancer activity with IC50 values of less than 10 μg/mL. Treating T3T fibroblast cells with compounds 2, 4, 5, 6, and 10 did not reveal a cytotoxic effect on the normal cells when compared to the control, cisplatin. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2021
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  • Date Issued: 2021-03

The classification of fuzzy subgroups of some finite non-cyclic abelian p- groups of rank 3, with emphasis on the number of distinct fuzzy subgroups

  • Authors: Appiah, Isaac Kwadwo
  • Date: 2021-03
  • Subjects: Fuzzy sets , Commutative algebra
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/20783 , vital:46563
  • Description: In [6] and [7] we classi_ed fuzzy subgroups of some rank-3 abelian groups of the form G = Zpn + Zp + Zp for any _xed prime integer p and any positive integer n, using the natural equivalence relation de_ned in [40]. In this thesis, we extend our classi_cation of fuzzy subgroups in [6] to the group G = Zpn + Zpm + Zp for any _xed prime integer p; m = 2 and any positive integer n using the same natural equivalence relation studied in [40]. We present and prove explicit polynomial formulae for the number of (i) subgroups, (ii) maximal chains of subgroups of G for any n;m _ 2 and (iii) distinct fuzzy subgroups for m = 2 and n _ 2. We have also developed user-friendly polynomial formulae for the number of (iv) subgroups, (v) maximal chains for the group G = Zpn + Zpm for any n;m _ 2; any _xed prime positive integer p and (vi) distinct fuzzy subgroups of Zpn + Zpm for m equal to 2 and 3, and n _ 2 and provided their proofs. , Thesis (PhD) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-03

Adolescent sexual reproductive health and rights in the Alice area, Eastern Cape Province of South Africa

  • Authors: Moko, Zukhanye
  • Date: 2021-02
  • Subjects: Reproductive health , Right to health , HIV infections
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20676 , vital:46423
  • Description: Sexual Reproductive Health (SRH) is a significant aspect of adolescent’s growth. Adolescents particularly girls face the risk of exposure to Human Immunodeficiency Virus (HIV), Sexually Transmitted Diseases (STDs), child marriages, high rates of unwanted pregnancy and the risk of those pregnancies can lead to unsafe abortion. In South Africa, considerable progress has been made in achieving improved access to Sexual Reproductive Health and Rights (SRHR) among the general population, however, some factors influencing SRHR of adolescents and young people have been slow to achieve. The study aims to investigate factors influencing Sexual Reproductive Health and Rights of adolescents in Alice, which is located in the Eastern Cape Province of South Africa. The Social-Ecological Model was considered appropriate for this study as it provides a comprehensive understanding of the multiple and interacting determinants of Sexual Reproductive Health and Rights. A qualitative methodology was adopted, involving focus groups with high school learners, in-depth interviews with institutional actors (Department of Health, Basic Education and Social Development), and participant observations. The study reveals that adolescents’ have access to Sexual Reproductive Health services from healthcare centres but only a few utilize or access them due to barriers such as the geographical location, denial and judgement about young people's sexuality limits their access to comprehensive knowledge to protect and promote their Sexual and Reproductive Health. The findings show that the adolescents who were most affected by Sexual Reproductive Health and Rights challenges were those from deep rural areas. They had minimal information/education compared to those residing in areas close to the town of Alice and major roads. Multi-sectoral interventions empowering adolescents and young people to exercise their rights to optimize SRHR service yield better results. , Thesis (MSc) -- Faculty of Science & Agriculture, 2021
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  • Date Issued: 2021-02

Bio-utilization of keratinous waste biomass for the production of keratinolytic proteases by Chryseobactreium aquifrigidense isolated from poultry waste dumpsite

  • Authors: Bokveld, Amahle
  • Date: 2021-02
  • Subjects: Keratin
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/20550 , vital:46120
  • Description: Keratin is an insoluble and a fibrous protein that is mostly found in feathers, animal wool, and hair, making them mechanically stable. Avian feathers are the most ubiquitously generated keratinous waste biomass from the poultry processing plants. Keratinous waste biomass valorization could produce amino acids and bioactive peptides. Hence, the bio-recycling of keratin-rich wastes bears an advantage over the chemical and thermal means. In recent times, the microbial keratinases continues to gain traction due to the litany of their potential significance in green technology. Consequently, this study assessed chicken feather degrading and keratinase production potentials of bacteria isolated from a local poultry dumpsite. Soil samples were collected from the poultry dumpsite. Bacteria were isolated using basal salt medium and screened for keratinolytic activity. The identification of potent chicken feather degrading bacterial isolates was through 16S rRNA gene sequence analysis. Keratinase production efficiency of isolates on chicken feather constituted medium was optimized. Hydrolysate's amino acid compositions were quantified, and the keratinases produced was characterized. Out of 22 bacteria isolated from the soil samples, 12 showed a varying degree of proteolytic activity on skimmed milk agar. Four (4) isolates, coded as FPS-01, FPS-07, FPS-09, WDS-06, out of the 12 proteolytic strains further displayed remarkable degradation of the intact chicken feather; percentage degradation ranged from 69 percent for FPS-01 to 88 percent for FPS-09. The extracellular keratinase activity ranged from 610.91 ± 56.57 U/mL for WDS-06 and 834.55 ± 66.86 U/mL for FPS-07. Additionally, the sulfhydryl group concentration quantified from the fermentation broth was 2.22 ± 0.37 (mM), 0.22 ± 0.08 (mM), 2.27 ± 0.09 (mM), and 2.76 ± 0.79 (mM) for FPS-01, FPS-07, FPS-09 and WDS-06, respectively. Based on 16S rRNA gene sequencing and phylogenetic analyses, the isolates FPS-07 and FPS-09 were identified as Chryseobacterium aquifrigidense FANN1 and Chryseobacterium aquifrigidense FANN2. Following the optimization process, the improved fermentation conditions were pH 6, inoculum side (4 percent, v/v), temperature (30 oC), and chicken feather (0.5-1.5 percent, w/v) for FANN1. FANN2 optimal fermentation conditions were pH 6, inoculum (5 percent, v/v), temperature (30 oC), and chicken feather (1.5 percent, w/v). Both bacterial isolates showed the highest extracellular keratinase production after 72 h of the fermentation time. Analysis of the hydrolysates generated from the bacteria fermentation showed a high concentration of arginine, serine, glutamic acid, glycine, proline, valine, and leucine at a respective concentration of 1.13, 1.02, 0.83, 0.94, 0.85, 0.84, and 0.86 (g/100g sample) against FANN1. Similarly, FANN2 generated hydrolysate showed high concentrations of glutamic acid, arginine, serine, aspartic acid, and glycine at this respective abundance 2.52, 1.92, 2.12, 2.25 and 1.9 (g/100g sample). Keratinases from FANN1 and FANN2 showed optimal catalytic efficiency at pH 8 and temperature between 40-50 oC. The enzyme was considerably thermostable at 40 oC and 50 oC after 120 min of preheating. Both FANN1 and FANN2 showed variable residual activity in the presence of the different metal ions. Keratinase from FANN1 recorded the following residual activity of Fe3+ (120 ± 5.06 percent), Ca2+ (100 ± 10.33 percent), Na+ (122 ± 2.95 percent), Al3+ (106 ± 10.33 percent). Likewise, FANN2 keratinase showed remarkable stability against Na+ (108 ± 13.71 percent), Ba2+ (102 ± 0.86 percent), Al3+ (105 ± 2.57 percent), and Ca2+ (96 ± 2.99 percent). Keratinase from FANN1 was catalytically activated after 60 min of pre-treatment with the following detergents, Sunlight (129 percent), Ariel (116 percent), MAQ (151 percent), and Surf (143 percent) compared to the control. FANN2 keratinase showed less stability with laundry detergents after 60 min of preincubation. FANN1 keratinase showed remarkable stability in the presence of chemical agents tested, with residual activity of 90 ± 0.18 percent, 105 ± 7.55 percent, 108 ± 4.31 percent, 123 ± 1.44 percent, 132 ± 1.26 percent, 96 ± 7.19 percent, and 101 ± 3.06 percent for DTT, hydrogen peroxide, DMSO, acetonitrile, triton X-100, tween-80, and SDS, respectively. The enzyme activity was also considerably inhibited by PMSF and EDTA, which suggested a mixed type of protease. Furthermore, keratinase from FANN2 was inhibited by EDTA, and such inhibition pattern grouped it as a metallo-type of protease. The enzyme was also stable in the presence of other chemical agents tested. Therefore, the findings suggest the isolates and their enzymes' relevance to sustainable recycling of recalcitrant keratinous wastes into high-value products with immense application potentials. The remarkable stability shown by keratinases from FANN1 and FANN2, post detergent and chemical agents pre-treatment, indicates promise for the biotechnology and industrial sector. , Thesis(MSc) (Microbiology) -- University of Fort Hare, 2021
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  • Date Issued: 2021-02

Bioconversion of chicken feather into amino acids and keratinase production by mesophilic Chryseobacterium proteolyticum and Pseudomonas aeruginosa isolated from municipal waste dumpsites

  • Authors: Giwu, Nonkonzo https://orcid.org/0000-0001-9416-7896
  • Date: 2021-02
  • Subjects: Poultry -- Processing , Proteolytic enzymes
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/22732 , vital:52720
  • Description: Chicken feathers are by-products of poultry processing which are generated in large amount because of the global growing demand for poultry meats. They have high contents of crude proteins in the form of keratin which could be valorized into digestible products. Keratinases are classified as a specific collection of proteolytic enzymes that have the ability for the degradation of recalcitrant keratinous substrates. Isolation and characterization of these enzymes from various microbial producers are gaining prominence in recent years due to their industrial and biotechnological application potentials. For this research, the collection of soil samples was done as well as the isolation of bacteria and the screening for keratinolytic activity. 16S rDNA sequencing and phylogenetic analysis were used to identify the isolates with efficient chicken feathers degrading capacity. Optimum conditions for the fermentation prcocess was enhanced for the production of keratinase. The fermentation broth was also analysed for various amino acids of protein, and the biochemical properties of the enzymes were likewise determined. Twenty two (22) bacteria were isolated from the soil samples, and 18 out of the 22 isolates showed proteolytic activity on solid media with diameters of halo zone that ranged from 5 ± 0.71 mm for isolate coded as PSS-03 to 25 ± 1.41 mm for isolate coded as PSS-06. Intact chicken feathers were degraded by proteolytic bacterial isolates in variable degree that ranged from 24percent for PSS-10 and 81percent for DSS-02. Extracellular keratinase production recorded for the isolates ranged from 63.63 ± 4.14 U/mL for PSS-10 to 693.63 ± 62.99 U/mL for DSS-02. Based on 16S rDNA sequence and phylogenetic analysis, the 2 isolates with remarkable keratinolytic activity coded as DSS-02 and PSS-14 were identified as Chryseobacterium proteolyticum FGNn and Pseudomonas aeruginosa GNFx. C. proteolyticum showed the maximum keratinase production of 756.36 U/mL after 72 h of incubation at optimized fermentation conditions which involved initial medium pH (4), incubation temperature (30 oC), inoculum size (2percent; v/v), and chicken feathers (1.5percent; w/v). Similarly, P. aeruginosa optimally produced keratinase (1055.45 U/mL) after 96 h of incubation at optimized fermentation conditions that involved initial medium pH (7-8), incubation temperature (30 oC), inoculum size (5percent; v/v), and chicken feathers (2.5percent; w/v). Furthermore, feather hydrolysate from C. proteolyticum FGNn had relatively higher abundance (>1.5g/100g sample) of arginine (1.85), serine (1.63), glycine (1.9) and lysine (1.62); while P. aeruginosa GNFx feather hydrolysate showed high abundance of arginine, serine, aspartic acid, glutamic acid, glycine, alanine, valine, and leucine with respective concentration of 2.06, 1.67, 2.39, 3.05, 1.87, 1.73, 1.56 and 1.65 (g/100g sample). The results showed that keratinases from the two bacterial isolates were optimally active at pH 8, and temperature of 50 oC for FGNn keratinase and 50-60 oC for GNFx keratinase. The enzymes displayed remarkable pH stability. Keratinase from C. proteolyticum was catalytically inhibited by EDTA and 1,10-phenanthroline but not affected by PMSF; while P. aeruginosa keratinase was not significantly affected by those class of protease inhibitors. Adiitionally, FGNn keratinase demonstrated high residual activity of 90percent, 103percent, 101percent, 110percent, 130, and 105percent in the presence of DTT, hydrogen peroxides, acetonitrile, triton X-100, tween-80 and SDS, respectively. Similarly, catalytic efficiency of GNFx keratinase was promoted in the presence of hydrogen peroxides (119percent), triton X-100 (140percent), tween-80 (150percent) and SDS (147percent) compared to the control. Furthermore, the keratinases from the both bacterial isolates exhibited catalytic efficiency enhancement and remarkable structural stability in the presence of laundry detergents tested. The findings from the study suggest the application potentials of the isolates for the bioconversion of recalcitrant keratinous wastes into digestible and quality protein hydrolysates. The properties of these microbial keratinases indicate that they may be exploited for various biotechnological and industrial processes especially in the formulation of detergents. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-02

Chicken feather delipidation by lipolytic bacteria isolated from an aquatic environment

  • Authors: Shiri, Tariro https://orcid.org/0000-0002-0290-9854
  • Date: 2021-02
  • Subjects: Keratin
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/21479 , vital:48693
  • Description: Keratinous biomass contributes a significant proportion of agro-based wastes in the ecosystem with minimal potentials for valuable product recovery. The generation of huge quantities of chicken feather from poultry processing farms prompts the valorization attempt via diverse avenues. Chicken feathers are a rich source of valuable keratin, yet the overall value chain is rudimentary based on unsustainable recovery techniques involving corrosive chemicals and high energy input processes. Although attempts have been made to extract keratin using microbial techniques successfully, the pre-treatment stage remains dominated by chemical use. Chicken feathers are composed of approximately 91percent keratin, 1percent lipids, and 8percent water. Therefore, lipid removal is a critical step in the valorization process as they contribute to access hindrance of the keratinases and other sulfitolytic systems to keratin. Consequently, the study undertook to explore the environment for lipolytic bacteria capable of degrading chicken feathers' lipid components. Sediment samples were collected for bacteria isolation. The bacteria were evaluated for lipolytic activity, and the potent isolates were identified based on 16S rRNA gene sequencing. The fermentation conditions for the production of extracellular lipases were optimized, and the produced lipases were characterized. Lastly, chicken feather lipids were hydrolysed with lipolytic bacteria. Out of twenty bacteria isolated from the sediment samples, six isolates coded as ACT003, ACT004, ACT010, ACT013, ACT016, and ACT019 showed lipolytic activity on solid media with a respective diameter of 12 mm, 66 mm, 29 mm, 11 mm, 12 mm, and 10 mm. Based on 16S rRNA gene sequencing and phylogenetic analysis, the isolates coded as ACT004 and ACT010 were identified as Bacillus sp. TTs1 and Bacillus sp. TTs2; and the nucleotide sequences were submitted to GenBank (NCBI) with the accession numbers MW556206 and MW556207, respectively. Bacillus sp. TTs1 showed the maximum lipase production of 641.25 U/mL at 72 h, under optimized conditions that included initial pH (5), inoculum size (2percent, v/v), incubation temperature (45 oC), agitation speed (140 rpm), CaCl2 (0.01percent, w/v), yeast extract (1percent, w/v), and tween-80 (10percent, v/v). Similarly, the lipase production by Bacillus sp. TTs2 peaked at 96 h with enzyme activity of 618.8 U/mL in improved fermentation conditions consisting of initial pH (5), inoculum size (2-8percent, v/v), incubation temperature (25 oC), agitation speed (180 rpm), CaCl2 (0.01percent, w/v), yeast extract and peptone (1percent, w/v), and tween-80 (10percent, v/v). The evaluation of chicken feather concentrations on free fatty acid liberation showed that 6-8percent (w/v) chicken feather was adequate with free fatty acids contents of 0.58percent and 0.86percent for Bacillus sp. TTs1 and Bacillus sp. TTs2, respectively. Both isolates' lipases showed remarkable catalytic efficiency at pH and temperature of 7 and 40oC, respectively. The comparative analysis of residual lipids between pre-and post-fermentation indicated a 39.9 ± 7.8percent and 51.2 ± 20.2percent hydrolysis efficiency for Bacillus sp. TTs1 and Bacillus sp. TTs2, respectively. This study's findings indicated the lipolytic potentials of Bacillus spp. and suggest the possibility of a full bio-based approach for chicken feather lipid removal in the valorization of chicken feathers. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
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  • Date Issued: 2021-02

Electrochemical sensing based on functionalised carbon dots prepared by bottom-up approach

  • Authors: Madikizela, Ziyanda https://orcid.org/0000-0003-0405-8464
  • Date: 2021-02
  • Subjects: Electrochemical analysis , Electrodes, Carbon
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/22545 , vital:52424
  • Description: This research was aimed at preparing carbon dots using the microwave method as a bottomup synthetic approach. The prepared carbon dots were them to be used as an electrode modifier in electrochemical detection of metal ion. The structure of the carbon dots prepared were characterized using different techniques including the FTIR, TEM, UV-Vis, PL, XRD and Raman Spectroscopy. It was observed that the nanoparticles consisted of carboxylic acid, amine and alcohol functional groups at their core and surface. UV-Vis and PL revealed that the carbon dots absorb more light in the visible and ultraviolet region, and the sizes of the carbon dots prepared were less than 10 nm. The carbon dots were then utilized for electrochemical sensing of Cd2+ ion, which is considered as one of harmful heavy metal ion when not controlled. Glassy carbon electrode modified with the carbon dots was utilized for the detection of Cd2+ through square wave voltammetry. Effect of different experimental parameters was studied which include electrode preparation, frequency, and amplitude. The electrochemical characterization of the electrode was done using the cyclic voltammetry and electrochemical impedance spectroscopy (EIS), the modified electrode was found conductive with much improved electrochemical performances. The obtained detection limit for Cd2+ sensing was 9.39 ppb, the developed C-dots modified GCE electrode was also tested with tap water Cd2+ spiked solution to demonstrate its implementation in real sample analysis. , Thesis (MA) -- Faculty of Science and Agriculture, 2021
  • Full Text:
  • Date Issued: 2021-02
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