Outcomes of Drug Resistant Tuberculosis in Two Rural District Hospitals, Eastern Cape Province, South Africa
- Authors: Lotz, John-D Knipe
- Date: 2021-02
- Subjects: Medicinal plants
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/6834 , vital:51018
- Description: Tuberculosis (TB) is still rampant in South Africa, and drug resistant tuberculosis (DR-TB) forms a significant part of this burden on both the health care system and economy. A number of interventions have recently been introduced to help curb the growing epidemic of DR-TB, including increasing access to novel and repurposed drugs, decentralisation of care, and a new shorter (9-11 month) treatment regimen recently endorsed by the World Health Organization (WHO). Significantly, this new regimen has now also become injectable-free (also known as an all-oral regimen). However, at the time of implementation in 2017, the shorter regimen was yet to be proven effective in a programmatic setting in South Africa. This is a retrospective cohort study to describe the outcomes in patients on short and long DR-TB treatment regimens, over five years, at two treatment sites in a rural setting in the Eastern Cape province of South Africa. It is the hope that elucidation of factors involved in affecting outcomes in DR-TB may direct future interventions in these two facilities, and the wider DR-TB program in South Africa , Thesis (Masters) -- Faculty of Health Sciences, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Lotz, John-D Knipe
- Date: 2021-02
- Subjects: Medicinal plants
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/6834 , vital:51018
- Description: Tuberculosis (TB) is still rampant in South Africa, and drug resistant tuberculosis (DR-TB) forms a significant part of this burden on both the health care system and economy. A number of interventions have recently been introduced to help curb the growing epidemic of DR-TB, including increasing access to novel and repurposed drugs, decentralisation of care, and a new shorter (9-11 month) treatment regimen recently endorsed by the World Health Organization (WHO). Significantly, this new regimen has now also become injectable-free (also known as an all-oral regimen). However, at the time of implementation in 2017, the shorter regimen was yet to be proven effective in a programmatic setting in South Africa. This is a retrospective cohort study to describe the outcomes in patients on short and long DR-TB treatment regimens, over five years, at two treatment sites in a rural setting in the Eastern Cape province of South Africa. It is the hope that elucidation of factors involved in affecting outcomes in DR-TB may direct future interventions in these two facilities, and the wider DR-TB program in South Africa , Thesis (Masters) -- Faculty of Health Sciences, 2021
- Full Text:
- Date Issued: 2021-02
Microalgal-bacterial flocs and extracellular polymeric substances for optimum function of integrated algal pond systems
- Authors: Jimoh, Taobat Adekilekun
- Date: 2021-10-29
- Subjects: Flocculation , Extracellular polymeric substances , Water Purification , Sewage Purification Anaerobic treatment , Integrated algae pond systems (IAPS) , Microalgal-bacterial flocs
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/191214 , vital:45071 , 10.21504/10962/191214
- Description: Despite the dire state of sanitation infrastructures, water scarcity, and the dwindling reserve of natural resources due to ever-increasing population growth, implementation of a suitable technology that can provide a solution to all these issues continues to be ignored. The integrated algal pond system (IAPS) is a wastewater treatment technology that combines the processes of anaerobic digestion and photosynthetic oxygenation to achieve wastewater treatment and facilitate the recovery of treated water and resources in the form of biogas and microalgal-bacterial biomass. The natural process of bioflocculation through microalgal-bacterial mutualism and production of extracellular polymeric substances (EPS) in high rate algal oxidation ponds (HRAOPs) of an IAPS increases efficiency of wastewater treatment and potentially enhances harvestability and biomass recovery, which could contribute significantly to the successful establishment of a biorefinery. Using a 500 PE pilot-scale IAPS supplied domestic sewage coupled with laboratory experiments, this study investigated the importance and function of in situ EPS production and MaB-floc formation in HRAOP. A metagenomic study revealed the biological components of the biomass or mixed liquor suspended solids (MLSS) produced in HRAOP and showed that the suspended biomass is composed largely of eukaryotes that were dominated by the colonial microalgae Pseudopediastrum sp. and Desmodesmus sp., and a diverse range of prokaryotes including bacteria and cyanobacteria. Dominance, within the bacterial population, by a sulphur-oxidizing bacterium, Thiothrix which comprised up to 80% of the prokaryotes, coincided with a period of poor flocculation and was therefore rationalized to have contributed to bulking and poor biomass settleability. Otherwise, good flocs were formed in the MLSS with settleability up to 95% and, within 1 h. The formation of MaB-flocs appeared to be dependent on EPS concentration of the mixed liquor due to the observed positive correlation between soluble EPS (S-EPS), biomass concentration, and settleability. The contribution and role of MLSS components towards the formation and sustenance of MaB-flocs were further demonstrated in laboratory experiments using pure strains of microalgae, cyanobacteria, and bacteria. Results showed that pure cultures of dominant microalgae in MLSS, Pseudopediastrum sp. and Desmodesmus sp. achieved a rapid 92 and 75% settleability within 3 h. A self-flocculating filamentous cyanobacterium, Leptolyngbya strain ECCN 20BG was isolated, characterized, and shown to achieve 99% settleability within 5 min by forming large tightly aggregated flocs. In further experiments, this strain was found to improve the settleability of MLSS by an average of 20%. Bacterial strains identified as Bacillus strain ECCN 40b, Bacillus strain ECCN 41b, Planococcus strain ECCN 45b, and Exiguobacterium strain ECCN 46b were also observed to produce sticky EPS-like materials in pure cultures that could also contribute to the aggregation of cells in a mixed environment. Given these results, various factors and/or mechanisms that might enhance microbial aggregation and biomass recovery from HRAOP MLSS were identified in this study and include; (1) dominance by larger colonial microalgae prevents disintegration of MaB-flocs and enhances recovery of biomass from MLSS by gravity sedimentation, (2) presence of filamentous cyanobacteria species that can self-flocculate to form an interwoven network of filaments may play an important role in the structural stability and settleability of MaB-flocs in MLSS, and (3) production of EPS to form the matrix or scaffold whereon all microbial components aggregate to develop a microenvironment. Indeed, all forms of EPS, except for that produced by Bacillus strain ECCN 41b, showed bioflocculating property and were able to serve as flocculants for the recovery of Chlorella, an alga known for its poor settleability. A combination of biochemical analyses and FTIR spectroscopy revealed the importance of carbohydrate enrichment of these biopolymers. Carbohydrate concentration in all forms of EPS was between 12 and 41% suggesting that production of these compounds by microbes within the MLSS contributed to MaB-floc formation. EPS extracted from bulk MLSS and EPS produced by Bacillus strains possessed some surface-active properties that were comparable to Triton X-100, indicating potential application in bioremediation and recovery of oil from contaminated soil and water. In particular, EPS generated from Bacillus strain ECCN 41b displayed relatively distinct properties including the quantity produced (> 500 mg/L), increased viscosity, inability to flocculate microalgal cells, a rhamnolipid content of 32%, and a higher surface-activity. Based on these results, Bacillus strain ECCN 41b was rationalized to produce anionic EPS with potential application in metal or oil recovery. In addition to EPS production, the bacteria Planococcus strain ECCN 45b and Exiguobacterium strain ECCN 46b appeared pigmented. Based on partial characterization using UV/Vis spectrophotometry, thin-layer chromatography, FTIR, and NMR, the pigments produced by these two strains appeared to be identical and were tentatively identified as ketocarotenoids. This study successfully demonstrated the importance of EPS production and formation of MaB-flocs in the MLSS from HRAOP of an IAPS treating domestic sewage. It is evident that increased settleability of the biomass does contribute to the reported efficiency of wastewater treatment by IAPS and would reduce both total suspended solids (TSS) and chemical oxygen demand (COD). In addition, demonstration that this biomass contains products of value such as carotenoids and EPS with potential for commercial use strengthens the idea of using IAPS as a platform technology for innovation of the wastewater treatment process to a biorefinery. , Thesis (PhD) -- Faculty of Science, Institute for Environmental Biotechnology, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Jimoh, Taobat Adekilekun
- Date: 2021-10-29
- Subjects: Flocculation , Extracellular polymeric substances , Water Purification , Sewage Purification Anaerobic treatment , Integrated algae pond systems (IAPS) , Microalgal-bacterial flocs
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/191214 , vital:45071 , 10.21504/10962/191214
- Description: Despite the dire state of sanitation infrastructures, water scarcity, and the dwindling reserve of natural resources due to ever-increasing population growth, implementation of a suitable technology that can provide a solution to all these issues continues to be ignored. The integrated algal pond system (IAPS) is a wastewater treatment technology that combines the processes of anaerobic digestion and photosynthetic oxygenation to achieve wastewater treatment and facilitate the recovery of treated water and resources in the form of biogas and microalgal-bacterial biomass. The natural process of bioflocculation through microalgal-bacterial mutualism and production of extracellular polymeric substances (EPS) in high rate algal oxidation ponds (HRAOPs) of an IAPS increases efficiency of wastewater treatment and potentially enhances harvestability and biomass recovery, which could contribute significantly to the successful establishment of a biorefinery. Using a 500 PE pilot-scale IAPS supplied domestic sewage coupled with laboratory experiments, this study investigated the importance and function of in situ EPS production and MaB-floc formation in HRAOP. A metagenomic study revealed the biological components of the biomass or mixed liquor suspended solids (MLSS) produced in HRAOP and showed that the suspended biomass is composed largely of eukaryotes that were dominated by the colonial microalgae Pseudopediastrum sp. and Desmodesmus sp., and a diverse range of prokaryotes including bacteria and cyanobacteria. Dominance, within the bacterial population, by a sulphur-oxidizing bacterium, Thiothrix which comprised up to 80% of the prokaryotes, coincided with a period of poor flocculation and was therefore rationalized to have contributed to bulking and poor biomass settleability. Otherwise, good flocs were formed in the MLSS with settleability up to 95% and, within 1 h. The formation of MaB-flocs appeared to be dependent on EPS concentration of the mixed liquor due to the observed positive correlation between soluble EPS (S-EPS), biomass concentration, and settleability. The contribution and role of MLSS components towards the formation and sustenance of MaB-flocs were further demonstrated in laboratory experiments using pure strains of microalgae, cyanobacteria, and bacteria. Results showed that pure cultures of dominant microalgae in MLSS, Pseudopediastrum sp. and Desmodesmus sp. achieved a rapid 92 and 75% settleability within 3 h. A self-flocculating filamentous cyanobacterium, Leptolyngbya strain ECCN 20BG was isolated, characterized, and shown to achieve 99% settleability within 5 min by forming large tightly aggregated flocs. In further experiments, this strain was found to improve the settleability of MLSS by an average of 20%. Bacterial strains identified as Bacillus strain ECCN 40b, Bacillus strain ECCN 41b, Planococcus strain ECCN 45b, and Exiguobacterium strain ECCN 46b were also observed to produce sticky EPS-like materials in pure cultures that could also contribute to the aggregation of cells in a mixed environment. Given these results, various factors and/or mechanisms that might enhance microbial aggregation and biomass recovery from HRAOP MLSS were identified in this study and include; (1) dominance by larger colonial microalgae prevents disintegration of MaB-flocs and enhances recovery of biomass from MLSS by gravity sedimentation, (2) presence of filamentous cyanobacteria species that can self-flocculate to form an interwoven network of filaments may play an important role in the structural stability and settleability of MaB-flocs in MLSS, and (3) production of EPS to form the matrix or scaffold whereon all microbial components aggregate to develop a microenvironment. Indeed, all forms of EPS, except for that produced by Bacillus strain ECCN 41b, showed bioflocculating property and were able to serve as flocculants for the recovery of Chlorella, an alga known for its poor settleability. A combination of biochemical analyses and FTIR spectroscopy revealed the importance of carbohydrate enrichment of these biopolymers. Carbohydrate concentration in all forms of EPS was between 12 and 41% suggesting that production of these compounds by microbes within the MLSS contributed to MaB-floc formation. EPS extracted from bulk MLSS and EPS produced by Bacillus strains possessed some surface-active properties that were comparable to Triton X-100, indicating potential application in bioremediation and recovery of oil from contaminated soil and water. In particular, EPS generated from Bacillus strain ECCN 41b displayed relatively distinct properties including the quantity produced (> 500 mg/L), increased viscosity, inability to flocculate microalgal cells, a rhamnolipid content of 32%, and a higher surface-activity. Based on these results, Bacillus strain ECCN 41b was rationalized to produce anionic EPS with potential application in metal or oil recovery. In addition to EPS production, the bacteria Planococcus strain ECCN 45b and Exiguobacterium strain ECCN 46b appeared pigmented. Based on partial characterization using UV/Vis spectrophotometry, thin-layer chromatography, FTIR, and NMR, the pigments produced by these two strains appeared to be identical and were tentatively identified as ketocarotenoids. This study successfully demonstrated the importance of EPS production and formation of MaB-flocs in the MLSS from HRAOP of an IAPS treating domestic sewage. It is evident that increased settleability of the biomass does contribute to the reported efficiency of wastewater treatment by IAPS and would reduce both total suspended solids (TSS) and chemical oxygen demand (COD). In addition, demonstration that this biomass contains products of value such as carotenoids and EPS with potential for commercial use strengthens the idea of using IAPS as a platform technology for innovation of the wastewater treatment process to a biorefinery. , Thesis (PhD) -- Faculty of Science, Institute for Environmental Biotechnology, 2021
- Full Text:
- Date Issued: 2021-10-29
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
- Full Text:
- Date Issued: 2021-02
- 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
- Full Text:
- Date Issued: 2021-02
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
- Full Text:
- Date Issued: 2021-04
- 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
- Full Text:
- Date Issued: 2021-04
Synthesis and characterization of molybdenum dichalcogenides nanoparticles via solution-processed technique for photovoltaic applications
- Authors: Shelter, Chikukwa Evernice
- Date: 2021-02
- Subjects: Nanoparticles , Colloids
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20653 , vital:46417
- Description: Energy generated from non-renewable energy sources has a drawback of prompted outflow of ozone harming substances. These drawbacks of the non-renewable energy have quickened innovative work of renewable power sources, since they have an advantage of the provision of a better, preserved, decent environment that is free from natural contamination and commotion. Photovoltaic devices are prevalent in improving the green energy utilization and defeating the natural concerns yielded from the current most overwhelming energy sources. Herein, the synthesis, characterization, and application of Molybdenum chalcogenide nanoparticles (NP) as alternative sources in the absorber layer of quantum dot solar sensitized cells (QDSSCs) is discussed. The MoS2 NPs were synthesized from the aliphatic and aromatic dithiocarbamate (DTC) ligands and complexes as precursors. The successful synthesis of the DTC ligands and MoDTC complexes was confirmed through characterization with a variety of techniques including 1H and 13C-NMR, Raman Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-visible spectroscopy (UV-VIS), Thermogravimetric analysis (TGA) and Derivative thermogravimetric (DTG) analysis. The synthesized MoDTC complexes (precursors) were further used in the synthesis of MoS2 nanoparticles. A bottom -up colloidal approach was employed for the synthesis of the MoX2 NPs. The successful synthesis of the NP was confirmed as the results from the diffractive peaks obtained from XRD which were positive and agreed in comparison with the standard. The diffractive peaks were shown in the planes (100), (002), (100) and (105) for MoS2 nanoparticles; (002), (100), (103) and (110) for MoSe2 and (0002), (0004), (103) as well as (0006) for the MoTe2 nanoparticles. The MoSe2 nanoparticles showed the least size of the nanoparticles followed by MoTe2 and lastly MoS2. These results agreed with the results obtained using SEM analysis. For the optical properties of the nanoparticles, UV-VIS and PL were used, the shift of the peaks from the red shift (600 nm) to the blue shift 270-5 nm and 287-9 nm (UV-VIS) confirmed that the nanoparticles were quantum confined. The application of the MoX2 NPs in QDSSCs was done with MoSe2 showing the greatest PCE of 7.86 percent followed by MoTe2 6.93 percent and lastly MoS2 with a PCE of 6.05 percent and 5.47 percent. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Shelter, Chikukwa Evernice
- Date: 2021-02
- Subjects: Nanoparticles , Colloids
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20653 , vital:46417
- Description: Energy generated from non-renewable energy sources has a drawback of prompted outflow of ozone harming substances. These drawbacks of the non-renewable energy have quickened innovative work of renewable power sources, since they have an advantage of the provision of a better, preserved, decent environment that is free from natural contamination and commotion. Photovoltaic devices are prevalent in improving the green energy utilization and defeating the natural concerns yielded from the current most overwhelming energy sources. Herein, the synthesis, characterization, and application of Molybdenum chalcogenide nanoparticles (NP) as alternative sources in the absorber layer of quantum dot solar sensitized cells (QDSSCs) is discussed. The MoS2 NPs were synthesized from the aliphatic and aromatic dithiocarbamate (DTC) ligands and complexes as precursors. The successful synthesis of the DTC ligands and MoDTC complexes was confirmed through characterization with a variety of techniques including 1H and 13C-NMR, Raman Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-visible spectroscopy (UV-VIS), Thermogravimetric analysis (TGA) and Derivative thermogravimetric (DTG) analysis. The synthesized MoDTC complexes (precursors) were further used in the synthesis of MoS2 nanoparticles. A bottom -up colloidal approach was employed for the synthesis of the MoX2 NPs. The successful synthesis of the NP was confirmed as the results from the diffractive peaks obtained from XRD which were positive and agreed in comparison with the standard. The diffractive peaks were shown in the planes (100), (002), (100) and (105) for MoS2 nanoparticles; (002), (100), (103) and (110) for MoSe2 and (0002), (0004), (103) as well as (0006) for the MoTe2 nanoparticles. The MoSe2 nanoparticles showed the least size of the nanoparticles followed by MoTe2 and lastly MoS2. These results agreed with the results obtained using SEM analysis. For the optical properties of the nanoparticles, UV-VIS and PL were used, the shift of the peaks from the red shift (600 nm) to the blue shift 270-5 nm and 287-9 nm (UV-VIS) confirmed that the nanoparticles were quantum confined. The application of the MoX2 NPs in QDSSCs was done with MoSe2 showing the greatest PCE of 7.86 percent followed by MoTe2 6.93 percent and lastly MoS2 with a PCE of 6.05 percent and 5.47 percent. , Thesis (MSc) (Chemistry) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
Investigations of water deficit interactions with heat and elevated carbon dioxide in wheat
- Authors: Mavindidze, Peter
- Date: 2021-02
- Subjects: Plants--Effect of heat on , Growth (Plants)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20664 , vital:46422
- Description: Future climate is predicted to be characterised by elevated carbon dioxide (eCO2), as well as more incidences of heat and water deficit. eCO2 has been widely reported as enhancing growth, biomass and grain yield. To investigate the interactive effects of abiotic stresses on genotypic performance, an experiment was established in open-top chambers at the University of Rhodes eCO2 facility in Grahamstown, South Africa. The specific objectives of the study were: i) to evaluate the effects of eCO2 on wheat grain yield, yield components and grain quality under heat and terminal water deficit conditions; ii) to identify cultivar sources of tolerance to combined water deficit and heat stress under eCO2; iii) to identify appropriate stress indices that can be used as screening tools for tolerance to combined effects of water deficit and heat stress under eCO2. A total of 19 wheat genotypes were evaluated in three environments varying in CO2, temperature and water deficit during the 2019 winter season. The experiment was laid out in a split-split plot design arranged in blocks inside the chambers. The parameters recorded were: leaf water potential (LWP), biomass content (TB), number of productive tillers (NPT), days to flowering (DTA), days to maturity (DTM), plant height (PH), thousand kernel weight (TKW), number of kernels per spike (KPS), kernel weight per spike (KWS) and total grain weight (TGW). The following stress indices were determined: tolerance index, stress tolerance, yield susceptibility index, mean productivity, geometric mean productivity, stress intensity index and yield index. Elevated atmospheric CO2 ameliorated the negative effects of combined heat and water deficit stress by enhancing LWP, NPT, KPS, TB and TGW. Wheat genotypes responded the same way to CO2 with respect to grain yield. Furthermore, adequate water supply mitigated the adverse effects of heat stress. In addition, the combined effects of eCO2, heat and water deficit are confounding and hypo-additive in nature. The separation of environmental effects revealed that significant genotypic responses on grain yield and biomass were caused by heat and water deficit stress, while eCO2 mitigated their negative effects, promoting growth and reproduction. Both Principal component analysis (PCA) biplot analysis and cultivar superiority measure proved to be reliable statistical tools since they managed to identify 13-5HTSBWYT-H18, Ncema and SST8135 as having both specific adaptations to future climates as well as wide adaption to multiple environments. The genotypes may be used as sources (parents for crosses) for wide adaptation in breeding programmes in the wake of predicted future climate environments. PCA biplot analysis identified mean productivity (MP) and geometric mean productivity (GMP) as the best indices; hence can also be as secondary traits complimenting traditional agronomic and physiological traits in wheat breeding under environments varying in water availability, CO2 and temperature. The interactive effects of eCO2 with heat and water deficit stress did not significantly compromise the grain physical characteristics, flour extraction, protein content, falling number and flour ash. eCO2 ameliorated the negative effects of heat and water deficit by increasing protein content by 4.75 percent , Thesis (MSc) (Crop Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Mavindidze, Peter
- Date: 2021-02
- Subjects: Plants--Effect of heat on , Growth (Plants)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20664 , vital:46422
- Description: Future climate is predicted to be characterised by elevated carbon dioxide (eCO2), as well as more incidences of heat and water deficit. eCO2 has been widely reported as enhancing growth, biomass and grain yield. To investigate the interactive effects of abiotic stresses on genotypic performance, an experiment was established in open-top chambers at the University of Rhodes eCO2 facility in Grahamstown, South Africa. The specific objectives of the study were: i) to evaluate the effects of eCO2 on wheat grain yield, yield components and grain quality under heat and terminal water deficit conditions; ii) to identify cultivar sources of tolerance to combined water deficit and heat stress under eCO2; iii) to identify appropriate stress indices that can be used as screening tools for tolerance to combined effects of water deficit and heat stress under eCO2. A total of 19 wheat genotypes were evaluated in three environments varying in CO2, temperature and water deficit during the 2019 winter season. The experiment was laid out in a split-split plot design arranged in blocks inside the chambers. The parameters recorded were: leaf water potential (LWP), biomass content (TB), number of productive tillers (NPT), days to flowering (DTA), days to maturity (DTM), plant height (PH), thousand kernel weight (TKW), number of kernels per spike (KPS), kernel weight per spike (KWS) and total grain weight (TGW). The following stress indices were determined: tolerance index, stress tolerance, yield susceptibility index, mean productivity, geometric mean productivity, stress intensity index and yield index. Elevated atmospheric CO2 ameliorated the negative effects of combined heat and water deficit stress by enhancing LWP, NPT, KPS, TB and TGW. Wheat genotypes responded the same way to CO2 with respect to grain yield. Furthermore, adequate water supply mitigated the adverse effects of heat stress. In addition, the combined effects of eCO2, heat and water deficit are confounding and hypo-additive in nature. The separation of environmental effects revealed that significant genotypic responses on grain yield and biomass were caused by heat and water deficit stress, while eCO2 mitigated their negative effects, promoting growth and reproduction. Both Principal component analysis (PCA) biplot analysis and cultivar superiority measure proved to be reliable statistical tools since they managed to identify 13-5HTSBWYT-H18, Ncema and SST8135 as having both specific adaptations to future climates as well as wide adaption to multiple environments. The genotypes may be used as sources (parents for crosses) for wide adaptation in breeding programmes in the wake of predicted future climate environments. PCA biplot analysis identified mean productivity (MP) and geometric mean productivity (GMP) as the best indices; hence can also be as secondary traits complimenting traditional agronomic and physiological traits in wheat breeding under environments varying in water availability, CO2 and temperature. The interactive effects of eCO2 with heat and water deficit stress did not significantly compromise the grain physical characteristics, flour extraction, protein content, falling number and flour ash. eCO2 ameliorated the negative effects of heat and water deficit by increasing protein content by 4.75 percent , Thesis (MSc) (Crop Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
The Relationship Between Food Sharing and Social Cohesion among Local Farmers: a case study of Ntafufu Location, Port St Johns Municipality.
- Mphompo, Aphiwe (https://orcid.org/ 0000-0003-0370-8007)
- Authors: Mphompo, Aphiwe (https://orcid.org/ 0000-0003-0370-8007)
- Date: 2021-02
- Subjects: Food supply , Social integration , Food relief
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20981 , vital:46876
- Description: The overall aim of this study was to examine how food sharing at Ntafufu location in Port St Johns (Republic of South Africa), augments social cohesion among local farmers. A mixed-method approach was used for this study. This study used a triangulation research method to measure the correlation between food sharing and social cohesion and to ensure that it is statistically sound, certainly gaining rich data from the study population. Focus groups and questionnaires were used to collect data. The researcher used thematic analysis for qualitative analysis and Statistical Packages for the Social Science (SPSS) for quantitative analysis. The researcher did not include the whole population. The researcher only interviewed selected participants, and these participants were taken from the study population. There were 13 participants for qualitative research and 43 participants for quantitative research totalling 56 participants. The findings revealed that there is a relationship between food sharing and social cohesion. An important finding to emerge in this study is that food sharing alleviates poverty. However, several limitations need to be considered. For instance, witchcraft was mentioned as a challenge for this practice. , Thesis (MSoc) (Anthropology) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Mphompo, Aphiwe (https://orcid.org/ 0000-0003-0370-8007)
- Date: 2021-02
- Subjects: Food supply , Social integration , Food relief
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20981 , vital:46876
- Description: The overall aim of this study was to examine how food sharing at Ntafufu location in Port St Johns (Republic of South Africa), augments social cohesion among local farmers. A mixed-method approach was used for this study. This study used a triangulation research method to measure the correlation between food sharing and social cohesion and to ensure that it is statistically sound, certainly gaining rich data from the study population. Focus groups and questionnaires were used to collect data. The researcher used thematic analysis for qualitative analysis and Statistical Packages for the Social Science (SPSS) for quantitative analysis. The researcher did not include the whole population. The researcher only interviewed selected participants, and these participants were taken from the study population. There were 13 participants for qualitative research and 43 participants for quantitative research totalling 56 participants. The findings revealed that there is a relationship between food sharing and social cohesion. An important finding to emerge in this study is that food sharing alleviates poverty. However, several limitations need to be considered. For instance, witchcraft was mentioned as a challenge for this practice. , Thesis (MSoc) (Anthropology) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
An analysis of students’ constructions of the ‘fees must Fall’ movement at an historically black university
- Authors: Chandler, Kelly Jean
- Date: 2021-02
- Subjects: Student movements , College students--Political activity , Student protesters
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21058 , vital:46939
- Description: The ‘Fees Must Fall’ movement which occured in 2015 and 2016 was a major national event which affected most higher education institutions in South Africa. This research considers the constructions of the ‘Fees Must Fall’ movement at an historically black university, namely, the University of Fort Hare. Furthermore, the research analyzes how students are positioned in their constructions in relation to the movement. The study aims to contribute to the understanding of the lived experiences of student activists in the 2015 and 2016 ‘Fees Must Fall’ movement at the University of Fort Hare. The data collection method used was a convenience sampling method with seven participants interviewed. Making use of the guidelines of a Foucauldian Discourse Analysis, four primary discourses were identified from the data collected: coercion discourses; fear discourses; financial discourses; and meritocracy discourses. The positions of students were varied and consisted of both agentic and submissive positions, with the student representative council frequently being positioned dominantly. The theoretical framework also included Michel Foucault’s theories of governmentality and biopower which contributed significantly to the understandings of institutional power in the university context. The research is conducted against ethical backdrop of the philosophies and guidelines of postcolonial psychology. The broader context of South Africa is observed and discussed, specifically recognizing the legacy of apartheid and other historical antecedents such as colonization. The issues of transformation, institutional racism, and decolonization are placed at the forefront of this research endeavour. , Thesis (MSoc Sci) (Psychology) - - University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Chandler, Kelly Jean
- Date: 2021-02
- Subjects: Student movements , College students--Political activity , Student protesters
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21058 , vital:46939
- Description: The ‘Fees Must Fall’ movement which occured in 2015 and 2016 was a major national event which affected most higher education institutions in South Africa. This research considers the constructions of the ‘Fees Must Fall’ movement at an historically black university, namely, the University of Fort Hare. Furthermore, the research analyzes how students are positioned in their constructions in relation to the movement. The study aims to contribute to the understanding of the lived experiences of student activists in the 2015 and 2016 ‘Fees Must Fall’ movement at the University of Fort Hare. The data collection method used was a convenience sampling method with seven participants interviewed. Making use of the guidelines of a Foucauldian Discourse Analysis, four primary discourses were identified from the data collected: coercion discourses; fear discourses; financial discourses; and meritocracy discourses. The positions of students were varied and consisted of both agentic and submissive positions, with the student representative council frequently being positioned dominantly. The theoretical framework also included Michel Foucault’s theories of governmentality and biopower which contributed significantly to the understandings of institutional power in the university context. The research is conducted against ethical backdrop of the philosophies and guidelines of postcolonial psychology. The broader context of South Africa is observed and discussed, specifically recognizing the legacy of apartheid and other historical antecedents such as colonization. The issues of transformation, institutional racism, and decolonization are placed at the forefront of this research endeavour. , Thesis (MSoc Sci) (Psychology) - - University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
Exploring how Grade 9 Physical Science teachers mediate learning of the topic of chemical changes
- Likando, Orrice Munukayumbwa
- Authors: Likando, Orrice Munukayumbwa
- Date: 2021-04
- Subjects: Science -- Study and teaching (Secondary) -- Namibia , Chemistry -- Study and teaching (Secondary) -- Namibia , Culturally relevant pedagogy , Pedagogical content knowledge , Prior learning -- Namibia
- Language: English
- Type: thesis , text , Masters , MEd
- Identifier: http://hdl.handle.net/10962/177918 , vital:42890
- Description: The examiners’ reports for 2013-2018 indicated that learners consistently perform poorly in questions based on chemical changes. My assumption is that the reason why learners are challenged with understanding the topic of chemical changes could be due to the way this topic is taught. It is against this background that this study explored how grade 9 Physical Science teachers mediated learning of the topic of chemical changes. The study is underpinned by an interpretive paradigm. Within the interpretive paradigm, a qualitative case study research design was employed. It was conducted at two different schools in the Otjozondjupa region with two Physical Science teachers. Data were collected using semi-structured interviews, lesson observations, stimulated recall interviews, and teachers’ reflections. The study is informed by Vygotsky’s socio-cultural theory together with Shulman’s pedagogical content knowledge as the theoretical frameworks. A thematic approach to data analysis was adopted. That is, qualitative data were analysed inductively to come up with sub-themes to form themes. Moreover, validation and trustworthiness were completed through data triangulation, member checking, and watching videotaped lessons with the participants. The findings of this study revealed that the topic of chemical changes has many examples which can be used during mediation. Teachers seemed to be aware of integrating learners’ experiences into their lessons. Furthermore, they were aware that they should improvise resources during mediation of learning. In contrast, during lesson observations, the findings revealed an imbalance between this awareness and the actual knowledge of using easily accessible materials, and the elicitation and integration of prior knowledge throughout the science lessons. Moreover, hands-on practical activities were lacking in the mediation process and instead, traditional methods of teaching tended to dominate. Nonetheless, teachers’ reflections influenced them to analyse and strengthen their lessons. Thus, the study recommends that there is a need for teachers to have mentorships and platforms which can expose them to the knowledge of different types of easily accessible materials. This might strengthen their PCK. Teachers are also encouraged to do some reflections after very lesson as these have a potential to influence their pedagogical practices. , Thesis (MEd) -- Faculty of Education, Education, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Likando, Orrice Munukayumbwa
- Date: 2021-04
- Subjects: Science -- Study and teaching (Secondary) -- Namibia , Chemistry -- Study and teaching (Secondary) -- Namibia , Culturally relevant pedagogy , Pedagogical content knowledge , Prior learning -- Namibia
- Language: English
- Type: thesis , text , Masters , MEd
- Identifier: http://hdl.handle.net/10962/177918 , vital:42890
- Description: The examiners’ reports for 2013-2018 indicated that learners consistently perform poorly in questions based on chemical changes. My assumption is that the reason why learners are challenged with understanding the topic of chemical changes could be due to the way this topic is taught. It is against this background that this study explored how grade 9 Physical Science teachers mediated learning of the topic of chemical changes. The study is underpinned by an interpretive paradigm. Within the interpretive paradigm, a qualitative case study research design was employed. It was conducted at two different schools in the Otjozondjupa region with two Physical Science teachers. Data were collected using semi-structured interviews, lesson observations, stimulated recall interviews, and teachers’ reflections. The study is informed by Vygotsky’s socio-cultural theory together with Shulman’s pedagogical content knowledge as the theoretical frameworks. A thematic approach to data analysis was adopted. That is, qualitative data were analysed inductively to come up with sub-themes to form themes. Moreover, validation and trustworthiness were completed through data triangulation, member checking, and watching videotaped lessons with the participants. The findings of this study revealed that the topic of chemical changes has many examples which can be used during mediation. Teachers seemed to be aware of integrating learners’ experiences into their lessons. Furthermore, they were aware that they should improvise resources during mediation of learning. In contrast, during lesson observations, the findings revealed an imbalance between this awareness and the actual knowledge of using easily accessible materials, and the elicitation and integration of prior knowledge throughout the science lessons. Moreover, hands-on practical activities were lacking in the mediation process and instead, traditional methods of teaching tended to dominate. Nonetheless, teachers’ reflections influenced them to analyse and strengthen their lessons. Thus, the study recommends that there is a need for teachers to have mentorships and platforms which can expose them to the knowledge of different types of easily accessible materials. This might strengthen their PCK. Teachers are also encouraged to do some reflections after very lesson as these have a potential to influence their pedagogical practices. , Thesis (MEd) -- Faculty of Education, Education, 2021
- Full Text:
- Date Issued: 2021-04
Perceptions and experience of school violence among teachers and learners within a black township in the Sarah Baartman District, Eastern Cape, South Africa
- Authors: Ndemka, Sibulela
- Date: 2021-10-29
- Subjects: School violence South Africa Eastern Cape , Teachers South Africa Eastern Cape Attitudes , High school students South Africa Eastern Cape Attitudes , High school students Conduct of life , High school students Economic conditions , High school students Social conditions , Social constructionism South Africa Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190760 , vital:45025
- Description: In exploring the knowledge/awarness of school violence within the teacher and student school relationship. The principal objective of the study was to investigate the perceptions and experiences of school violence among teachers and learners by reference to a public high school in a historically black African, working class township in the Sarah Baartman District Municipality, Eastern Cape Province, South Africa. The high school was chosen for its geographical location within the community and relative nature of shared stories of violence within the surrounding vicinity. The conceptual, theoretical, and analytical frameworks underpinning this study is social constructionism theory, expanding from the theoretical claim that violence is socially constructed through the process of socialisation and institutionalization. The study reviewed relavant literature on violence in South African schools highlighting the relationship of school violence to current social and educational challenges and crises and the impact that school violence has on learners, teachers, and communities. The research methodology employed is qualitative and evidence was derived through semi-structured in-depth interviews. A sample male and female teachers and learners were recruited through networking. The researcher recruited participants outside the school and through participant referrals to uncover intricacies of school violence drawing on relevant literature in relation to the dynamics of this social and institutional problem. Data was analysed and thematically presented in line with the research objectives. The study findings imply that school violence is complex and gendered. Arguing that cultural, socio-economic, family, community, and social interpersonal factors account for school violence in South Africa. Male teachers and students mostly bieng the victims and perpetrators, implicating this behaviour to a culture of toxic masculinity and shared complicities as contributing factors to school violence. In addition, the study found that the change in status and expectations of boys who return from initiation sometimes provoked violence between initiated learners and adults who did not accord them the respect expected post-initiation. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Ndemka, Sibulela
- Date: 2021-10-29
- Subjects: School violence South Africa Eastern Cape , Teachers South Africa Eastern Cape Attitudes , High school students South Africa Eastern Cape Attitudes , High school students Conduct of life , High school students Economic conditions , High school students Social conditions , Social constructionism South Africa Eastern Cape
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190760 , vital:45025
- Description: In exploring the knowledge/awarness of school violence within the teacher and student school relationship. The principal objective of the study was to investigate the perceptions and experiences of school violence among teachers and learners by reference to a public high school in a historically black African, working class township in the Sarah Baartman District Municipality, Eastern Cape Province, South Africa. The high school was chosen for its geographical location within the community and relative nature of shared stories of violence within the surrounding vicinity. The conceptual, theoretical, and analytical frameworks underpinning this study is social constructionism theory, expanding from the theoretical claim that violence is socially constructed through the process of socialisation and institutionalization. The study reviewed relavant literature on violence in South African schools highlighting the relationship of school violence to current social and educational challenges and crises and the impact that school violence has on learners, teachers, and communities. The research methodology employed is qualitative and evidence was derived through semi-structured in-depth interviews. A sample male and female teachers and learners were recruited through networking. The researcher recruited participants outside the school and through participant referrals to uncover intricacies of school violence drawing on relevant literature in relation to the dynamics of this social and institutional problem. Data was analysed and thematically presented in line with the research objectives. The study findings imply that school violence is complex and gendered. Arguing that cultural, socio-economic, family, community, and social interpersonal factors account for school violence in South Africa. Male teachers and students mostly bieng the victims and perpetrators, implicating this behaviour to a culture of toxic masculinity and shared complicities as contributing factors to school violence. In addition, the study found that the change in status and expectations of boys who return from initiation sometimes provoked violence between initiated learners and adults who did not accord them the respect expected post-initiation. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2021
- Full Text:
- Date Issued: 2021-10-29
: the representation of rape in Lewis Nkosi’s Mating Birds and Arthur Maimane’s Hate No More
- Authors: Yawa, Sibulele Yola
- Date: 2021-02
- Subjects: South Africa--Politics and government--1994 , Post-apartheid era--South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21134 , vital:47131
- Description: The main aim of this thesis is to provide a literary study through a comparative analysis of how sexual politics are played out in the texts Mating Birds by Lewis Nkosi and Hate No More by Arthur Maimane. It seeks to determine the modalities of representation of rape in each text and also to investigate the extent to which the novels are similar or different in the way in which they represent sexual politics or the politics of rape during the apartheid era. This investigation was done using Frantz Fanon‟s postcolonial theory and, particularly, his seminal work, Black Skin, White Masks. Most importantly, for the purpose of this study, is Fanon‟s chapter on the love/sexual relationships between the man of colour and the white woman. This is helpful as Fanon touches on what he believes the attraction of the man of colour to the white woman stems from. Using Fanon‟s theory, one discovers that the motivation for Ndi Sibiya to allegedly rape Veronica stems from his anger at the system of apartheid and its oppression of black people. This is similar to Philip Mokone‟s case; the novel explicitly states that he was motivated by anger and his rape of Jean Ryan was a form of communication to the white people and the apartheid system. , Thesis (MA) (English) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Yawa, Sibulele Yola
- Date: 2021-02
- Subjects: South Africa--Politics and government--1994 , Post-apartheid era--South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21134 , vital:47131
- Description: The main aim of this thesis is to provide a literary study through a comparative analysis of how sexual politics are played out in the texts Mating Birds by Lewis Nkosi and Hate No More by Arthur Maimane. It seeks to determine the modalities of representation of rape in each text and also to investigate the extent to which the novels are similar or different in the way in which they represent sexual politics or the politics of rape during the apartheid era. This investigation was done using Frantz Fanon‟s postcolonial theory and, particularly, his seminal work, Black Skin, White Masks. Most importantly, for the purpose of this study, is Fanon‟s chapter on the love/sexual relationships between the man of colour and the white woman. This is helpful as Fanon touches on what he believes the attraction of the man of colour to the white woman stems from. Using Fanon‟s theory, one discovers that the motivation for Ndi Sibiya to allegedly rape Veronica stems from his anger at the system of apartheid and its oppression of black people. This is similar to Philip Mokone‟s case; the novel explicitly states that he was motivated by anger and his rape of Jean Ryan was a form of communication to the white people and the apartheid system. , Thesis (MA) (English) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
Democratic citizenship in mathematics teachers’ preparation in South African Universities
- Olawale, Babawande Emmanuel https://orcid.org/ 0000-0001-5265-1583
- Authors: Olawale, Babawande Emmanuel https://orcid.org/ 0000-0001-5265-1583
- Date: 2021-02
- Subjects: Citizenship -- Study and teaching , Authoritarianism , Mathematics -- Study and teaching
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/20079 , vital:45107
- Description: Promoting a clearer understanding of the role of schools in developing democratic dispositions among young citizens is a matter of importance across the world. This is because school is believed to be the best place where future free and democratic citizens can be prepared. Similarly, it is a place where young people are equipped with the necessary skills and knowledge that will assist them in deliberating democratically, developing a better understanding of political structures and economic and world history, and learning the relevant numeracy, literacy and critical thinking skills. Unfortunately, current teacher education programmes appear to represent potential stumbling blocks to schooling playing a greater role in educating the youth for democracy and democratic citizenship. This study explored two contradictory theoretical roles for mathematics teacher education programmes, in relation to power and control in education and society. The first is that, in reality, mathematics teacher education is essentially re-productive, in that its authoritarian relationship does not encourage confrontational discussion or critique, or challenge existing and dominant practices. The second is that, in a world where democracy is increasingly becoming a global phenomenon central to development, teacher education is (or should be) essentially democratic in nature. Thus, underpinned by the interpretivist paradigm, this study employed a qualitative research approach. It also utilised a case study design as a strategy for data collection, in order to explore how the mathematics teacher education programmes in South African universities prepare learners for democratic citizenship. As such, three universities in two provinces in South Africa participated in the study, and data were collected through interviews, observation and document reviews. At each institution, interviews were carried out with mathematics teacher educators and pre-service mathematics student teachers in their second to fourth year of study. Similarly, observations took place in different teaching sessions at each institution, and in different formats. Relevant documents were also reviewed for the study. The research findings revealed that the concepts of democracy and democratic citizenship are multifaceted. The participants’ understanding of these concepts was influenced by their individual expectations, as well as their social, political and economic environments, among many other factors. In addition, it was evident that mathematics teacher education programmes play a significant role in developing socially active citizens and democratic mathematics teachers. The research findings revealed, however, that contradictions exist between pedagogical approaches that are capable of developing democratic citizens, mathematics teacher educators’ ideal image of their practices within the classroom, and the participants’ conception of mathematics. As a result, no engagement occurs in social and critical pedagogy within mathematics education classrooms, to allow learners to view mathematics as a tool for confronting issues of justice and inequality in their community and the world at large. The research findings also revealed that the practices of the main structures which are tasked with the responsibility of promoting democratic practices within higher education institutions seem ineffective, as a result of favouritism and an autocratic approach to decision making. Based on the research findings, a recommendation is made that mathematics educators democratise their classrooms, in order to develop democratic citizens who are committed to democratic principles. Another recommendation is that, in their mathematics classrooms, educators use a problem-posing pedagogical approach which is capable of challenging power structures, thereby empowering learners as users of mathematics. This will not be possible without a professional development programme guiding mathematics teacher educators in establishing and managing their democratic classrooms. Similarly, it is recommended that student representative councils, as the structures that are best known for supporting democratic citizenship at universities, strive to follow the basic principles of democratic governance. Finally, the researcher concluded that mathematics education and the task of preparing mathematics student teachers for democratic citizenship are of the utmost importance, if South Africans are to cultivate and maintain a democracy that contributes to a culture which fundamentally supports democratic principles. , Thesis (PhD) -- Faculty of Education, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Olawale, Babawande Emmanuel https://orcid.org/ 0000-0001-5265-1583
- Date: 2021-02
- Subjects: Citizenship -- Study and teaching , Authoritarianism , Mathematics -- Study and teaching
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/20079 , vital:45107
- Description: Promoting a clearer understanding of the role of schools in developing democratic dispositions among young citizens is a matter of importance across the world. This is because school is believed to be the best place where future free and democratic citizens can be prepared. Similarly, it is a place where young people are equipped with the necessary skills and knowledge that will assist them in deliberating democratically, developing a better understanding of political structures and economic and world history, and learning the relevant numeracy, literacy and critical thinking skills. Unfortunately, current teacher education programmes appear to represent potential stumbling blocks to schooling playing a greater role in educating the youth for democracy and democratic citizenship. This study explored two contradictory theoretical roles for mathematics teacher education programmes, in relation to power and control in education and society. The first is that, in reality, mathematics teacher education is essentially re-productive, in that its authoritarian relationship does not encourage confrontational discussion or critique, or challenge existing and dominant practices. The second is that, in a world where democracy is increasingly becoming a global phenomenon central to development, teacher education is (or should be) essentially democratic in nature. Thus, underpinned by the interpretivist paradigm, this study employed a qualitative research approach. It also utilised a case study design as a strategy for data collection, in order to explore how the mathematics teacher education programmes in South African universities prepare learners for democratic citizenship. As such, three universities in two provinces in South Africa participated in the study, and data were collected through interviews, observation and document reviews. At each institution, interviews were carried out with mathematics teacher educators and pre-service mathematics student teachers in their second to fourth year of study. Similarly, observations took place in different teaching sessions at each institution, and in different formats. Relevant documents were also reviewed for the study. The research findings revealed that the concepts of democracy and democratic citizenship are multifaceted. The participants’ understanding of these concepts was influenced by their individual expectations, as well as their social, political and economic environments, among many other factors. In addition, it was evident that mathematics teacher education programmes play a significant role in developing socially active citizens and democratic mathematics teachers. The research findings revealed, however, that contradictions exist between pedagogical approaches that are capable of developing democratic citizens, mathematics teacher educators’ ideal image of their practices within the classroom, and the participants’ conception of mathematics. As a result, no engagement occurs in social and critical pedagogy within mathematics education classrooms, to allow learners to view mathematics as a tool for confronting issues of justice and inequality in their community and the world at large. The research findings also revealed that the practices of the main structures which are tasked with the responsibility of promoting democratic practices within higher education institutions seem ineffective, as a result of favouritism and an autocratic approach to decision making. Based on the research findings, a recommendation is made that mathematics educators democratise their classrooms, in order to develop democratic citizens who are committed to democratic principles. Another recommendation is that, in their mathematics classrooms, educators use a problem-posing pedagogical approach which is capable of challenging power structures, thereby empowering learners as users of mathematics. This will not be possible without a professional development programme guiding mathematics teacher educators in establishing and managing their democratic classrooms. Similarly, it is recommended that student representative councils, as the structures that are best known for supporting democratic citizenship at universities, strive to follow the basic principles of democratic governance. Finally, the researcher concluded that mathematics education and the task of preparing mathematics student teachers for democratic citizenship are of the utmost importance, if South Africans are to cultivate and maintain a democracy that contributes to a culture which fundamentally supports democratic principles. , Thesis (PhD) -- Faculty of Education, 2021
- Full Text:
- Date Issued: 2021-02
Electrochemical sensing based on functionalised carbon dots prepared by bottom-up approach
- Madikizela, Ziyanda https://orcid.org/0000-0003-0405-8464
- 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
- 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
Succession politics and state administration in Africa: the case of Zimbabwe.
- Authors: Chikerema, Arthur Fidelis
- Date: 2021-02
- Subjects: Africa--Politics and government , Public administration , state governments
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/21355 , vital:48494
- Description: The research probes the impact of succession politics on state administration in Africa, Zimbabwe as a case study. Power transition in any political landscape promotes the regeneration and configuration of the political architecture and the functionality of the administrative apparatus of the state. Government performance may thus be viewed as a result of political processes and dynamics that influence governance in a polity. Political succession determines the composition of administrative organs of the state and many political leaders wish to work with administrative apparatus, which are compatible with their ideological orientation. Regular transfer of executive power is the major test of stability, legitimacy and maturity of a nation’s political system, but in Zimbabwe, political leaders have shown a consistent trajectory of violating or amending state and party constitutions to prolong their stay in power (Constitutional coup or a third term tragedy). This has been compelled by ruthless silencing of dissent by suffocating political activism culminating in strong personalities and weak institutions. Succession politics in Zimbabwe resembles executive dominance, egocentrism, excessive appointing powers which are compounded by lack of institutional framework for succession. This undermines the professional independence of the bureaucracy, which in turn inhibits the pursuit of sound governance. Therefore, passing the baton to the next leader has been a challenge; resulting in the personalization of, governments and political parties by leaders. While constitutions provide for elective congress for purposes of electing party leadership and/ or renewing their mandates, there is strong literature pointing to the capture of representative institutions such as Parliaments through strong normative values by leaders. This erodes the role of Parliaments or congresses as a democratic institution, as leaders have used it to “endorse” themselves. The research examines the influence of succession politics on state administration, especially on how the institution of the state and party politics in Zimbabwe conflate with the public administration system leading to state malfunction. This research adopts a qualitative research design that provides an understanding of underlying reasons, opinions, and motivations on political succession and state administration in Zimbabwe. Data was collected through in-depth interviews, complemented by document review and analyzed through thematic content analysis. The study found out that, despite the existence of the legal frameworks that promote seamless power transition, political, societal and historical factors exacerbate Zimbabwe’s succession dilemma. Colonial legacy, societal laxity, the military factor, capture of state institutions by the political elite, lack of a retirement institutional mechanism, the principle of sovereignty and politicization of the succession process were found as the major hindrances to Zimbabwe’s succession trajectory. It recommends broad based and genuine civil service, electoral, security and political (politics with ethics and values) reforms to dismantle the current legacy imbedded in the political system. , Thesis (PhD) (Public Administration) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Chikerema, Arthur Fidelis
- Date: 2021-02
- Subjects: Africa--Politics and government , Public administration , state governments
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/21355 , vital:48494
- Description: The research probes the impact of succession politics on state administration in Africa, Zimbabwe as a case study. Power transition in any political landscape promotes the regeneration and configuration of the political architecture and the functionality of the administrative apparatus of the state. Government performance may thus be viewed as a result of political processes and dynamics that influence governance in a polity. Political succession determines the composition of administrative organs of the state and many political leaders wish to work with administrative apparatus, which are compatible with their ideological orientation. Regular transfer of executive power is the major test of stability, legitimacy and maturity of a nation’s political system, but in Zimbabwe, political leaders have shown a consistent trajectory of violating or amending state and party constitutions to prolong their stay in power (Constitutional coup or a third term tragedy). This has been compelled by ruthless silencing of dissent by suffocating political activism culminating in strong personalities and weak institutions. Succession politics in Zimbabwe resembles executive dominance, egocentrism, excessive appointing powers which are compounded by lack of institutional framework for succession. This undermines the professional independence of the bureaucracy, which in turn inhibits the pursuit of sound governance. Therefore, passing the baton to the next leader has been a challenge; resulting in the personalization of, governments and political parties by leaders. While constitutions provide for elective congress for purposes of electing party leadership and/ or renewing their mandates, there is strong literature pointing to the capture of representative institutions such as Parliaments through strong normative values by leaders. This erodes the role of Parliaments or congresses as a democratic institution, as leaders have used it to “endorse” themselves. The research examines the influence of succession politics on state administration, especially on how the institution of the state and party politics in Zimbabwe conflate with the public administration system leading to state malfunction. This research adopts a qualitative research design that provides an understanding of underlying reasons, opinions, and motivations on political succession and state administration in Zimbabwe. Data was collected through in-depth interviews, complemented by document review and analyzed through thematic content analysis. The study found out that, despite the existence of the legal frameworks that promote seamless power transition, political, societal and historical factors exacerbate Zimbabwe’s succession dilemma. Colonial legacy, societal laxity, the military factor, capture of state institutions by the political elite, lack of a retirement institutional mechanism, the principle of sovereignty and politicization of the succession process were found as the major hindrances to Zimbabwe’s succession trajectory. It recommends broad based and genuine civil service, electoral, security and political (politics with ethics and values) reforms to dismantle the current legacy imbedded in the political system. , Thesis (PhD) (Public Administration) -- University of Fort Hare, 2021
- Full Text:
- 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
- Full Text:
- Date Issued: 2021-02
- 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
- Full Text:
- Date Issued: 2021-02
Systematics of the Afrotropical Chalcididae (Hymenoptera: Chalcidoidea)
- Authors: Faure, Sariana
- Date: 2021-10-29
- Subjects: Uncatalogued
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/192808 , vital:45266
- Description: Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Faure, Sariana
- Date: 2021-10-29
- Subjects: Uncatalogued
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/192808 , vital:45266
- Description: Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2021
- Full Text:
- Date Issued: 2021-10-29
Keratinous poultry wastes valorization through novel keratinases of Chryseobacterium cucumeris and Sphingobacterium multivorum isolated from poultry sludge
- Hendrick, Qaphela https://orcid.org/0000-0001-7529-8129
- Authors: Hendrick, Qaphela https://orcid.org/0000-0001-7529-8129
- Date: 2021-02
- Subjects: Agricultural wastes , Factory and trade waste
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21400 , vital:48537
- Description: Annually, about 55percent of keratinous wastes are generated from various agro-industrial processing farms in South Africa. These wastes are difficult to handle due to structural integrity; hence, they constitute environmental issues due to the disposal means. Degradation of keratinous wastes using microbial-based technology has been deemed advantageous as it generates products with high-end values. Therefore, in this study, chicken feather and soil samples were collected from a local poultry farm, and bacteria were isolated using basal salt media supplemented with chicken feathers. The isolates were evaluated for proteolytic and keratinolytic potentials. The potent isolates were identified through 16S rDNA sequence and phylogenetic analysis. Fermentation media were optimized for enhanced keratinase production, and the amino acids liberated in the media during feather biodegradation were quantified. The biochemical properties of the keratinases produced were likewise determined. Ten (10) proteolytic bacteria were obtained from 20 isolates recovered from the samples with a diameter of halo on skimmed milk agar plate ranging from 15.5 ± 0.71 (mm) for isolate coded as PSW-15 to 28 ± 1.41 (mm) for isolate coded as PSW-08. The proteolytic bacteria showed variable keratinolytic potentials with percentage feather degradation that ranged from 29percent for PSW-11 to 84percent for PSW-14, and keratinase activity ranging from 99.99 U/mL for PSW-15 to 761.82 U/mL for PSW-14. The most potent isolates coded as PSW-14 and PSW-16 were identified as Chryseobacterium cucumeris FHN1 and Sphingobacterium multivorum HNFx. Their nucleotide sequences were submitted to the GenBank as MW16587 and MK82939, respectively. The optimization of fermentation conditions; C. cucumeris FHN1 showed improved activity at pH 5 - 6, inoculum size (4percent, v/v), chicken feather concentration (1percent, w/v), fermentation temperature (25o C). Similarly, S. multivorum HNFx showed optimal activity at pH 4.0, inoculum size (5percent, v/v), chicken feather concentration (2.5percent, w/v), and fermentation temperature (25-30 oC). C. cucumeris FHN1 and S. multivorum HNFx showed maximum keratinase production of 485.54 U/mL and 526.36 U/mL at 96 h and 72 h of incubation period respectively. Serine, aspartic acid, glutamic acid, and proline were the most abundant amino acids in the degraded chicken feathers, and upon quantitation, the following concentration was respectively obtained; 3.71, 3.4, 4.19 and 4.35 (g/100g sample) against C. cucumeris FHN1. While S. multivorum HNFx yielded aspartic acid (2.04 g/100g sample) and glutamic acid (2.0 g/100g sample) in high concentration. The keratinases showed optimal catalytic efficiency at pH and temperature of 8.0 and 90 oC, respectively. C. cucumeris FHN1 keratinase was inhibited by metal ion chelating agents; EDTA and 1,10-phenanthroline, suggesting a metallo-type of protease. The enzyme showed remarkable stability after pre-treatment with DTT, Fe2+, Fe3+ and Cu2+, with respective residual activity of 108percent, 102percent, 114percent, and 104percent. The S. multivorum HNFx keratinase; activity was not inhibited by serine- and metallo-protease inhibitors. It maintained the following residual activity against the following chemical agents; DTT (124percent), hydrogen peroxide (152percent), DMSO (161percent), triton X-100 (152percent), tween-80 (101percent), and metal ions; Fe2+ (128percent), Fe3+ (104percent), K+ (117percent), Ca2+ (104percent), Na+ (103percent), Ba2+ (115percent), Al3+ (126percent). The enzyme showed a substantial loss of catalytic efficiency after pre-incubation with various laundry detergents. The keratinases' remarkable stability in the presence of various chemical agents and metal ions tested suggests biotechnological and industrial application potentials. Consequently, the isolates portend industrial relevance for keratinous waste valorization and an excellent source of keratinases of industrial relevance. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Hendrick, Qaphela https://orcid.org/0000-0001-7529-8129
- Date: 2021-02
- Subjects: Agricultural wastes , Factory and trade waste
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21400 , vital:48537
- Description: Annually, about 55percent of keratinous wastes are generated from various agro-industrial processing farms in South Africa. These wastes are difficult to handle due to structural integrity; hence, they constitute environmental issues due to the disposal means. Degradation of keratinous wastes using microbial-based technology has been deemed advantageous as it generates products with high-end values. Therefore, in this study, chicken feather and soil samples were collected from a local poultry farm, and bacteria were isolated using basal salt media supplemented with chicken feathers. The isolates were evaluated for proteolytic and keratinolytic potentials. The potent isolates were identified through 16S rDNA sequence and phylogenetic analysis. Fermentation media were optimized for enhanced keratinase production, and the amino acids liberated in the media during feather biodegradation were quantified. The biochemical properties of the keratinases produced were likewise determined. Ten (10) proteolytic bacteria were obtained from 20 isolates recovered from the samples with a diameter of halo on skimmed milk agar plate ranging from 15.5 ± 0.71 (mm) for isolate coded as PSW-15 to 28 ± 1.41 (mm) for isolate coded as PSW-08. The proteolytic bacteria showed variable keratinolytic potentials with percentage feather degradation that ranged from 29percent for PSW-11 to 84percent for PSW-14, and keratinase activity ranging from 99.99 U/mL for PSW-15 to 761.82 U/mL for PSW-14. The most potent isolates coded as PSW-14 and PSW-16 were identified as Chryseobacterium cucumeris FHN1 and Sphingobacterium multivorum HNFx. Their nucleotide sequences were submitted to the GenBank as MW16587 and MK82939, respectively. The optimization of fermentation conditions; C. cucumeris FHN1 showed improved activity at pH 5 - 6, inoculum size (4percent, v/v), chicken feather concentration (1percent, w/v), fermentation temperature (25o C). Similarly, S. multivorum HNFx showed optimal activity at pH 4.0, inoculum size (5percent, v/v), chicken feather concentration (2.5percent, w/v), and fermentation temperature (25-30 oC). C. cucumeris FHN1 and S. multivorum HNFx showed maximum keratinase production of 485.54 U/mL and 526.36 U/mL at 96 h and 72 h of incubation period respectively. Serine, aspartic acid, glutamic acid, and proline were the most abundant amino acids in the degraded chicken feathers, and upon quantitation, the following concentration was respectively obtained; 3.71, 3.4, 4.19 and 4.35 (g/100g sample) against C. cucumeris FHN1. While S. multivorum HNFx yielded aspartic acid (2.04 g/100g sample) and glutamic acid (2.0 g/100g sample) in high concentration. The keratinases showed optimal catalytic efficiency at pH and temperature of 8.0 and 90 oC, respectively. C. cucumeris FHN1 keratinase was inhibited by metal ion chelating agents; EDTA and 1,10-phenanthroline, suggesting a metallo-type of protease. The enzyme showed remarkable stability after pre-treatment with DTT, Fe2+, Fe3+ and Cu2+, with respective residual activity of 108percent, 102percent, 114percent, and 104percent. The S. multivorum HNFx keratinase; activity was not inhibited by serine- and metallo-protease inhibitors. It maintained the following residual activity against the following chemical agents; DTT (124percent), hydrogen peroxide (152percent), DMSO (161percent), triton X-100 (152percent), tween-80 (101percent), and metal ions; Fe2+ (128percent), Fe3+ (104percent), K+ (117percent), Ca2+ (104percent), Na+ (103percent), Ba2+ (115percent), Al3+ (126percent). The enzyme showed a substantial loss of catalytic efficiency after pre-incubation with various laundry detergents. The keratinases' remarkable stability in the presence of various chemical agents and metal ions tested suggests biotechnological and industrial application potentials. Consequently, the isolates portend industrial relevance for keratinous waste valorization and an excellent source of keratinases of industrial relevance. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
The optimisation of transportation methods for abalone (Haliotis midae Linnaeus, 1758 (Mollusca: Gastropoda)) larvae
- Authors: Bajaba, Sharone
- Date: 2021-02
- Subjects: Abalone fisheries , Haliotis midae , Abalone culture
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20561 , vital:46124
- Description: Sea ranching has been identified as a viable method for enhancing the natural stock of overexploited abalone (Haliotis midae). Currently, this process involves transporting live juvenile H. midae to the seeding site where they are released onto the reef however this is both costly and logistically problematic. Transportation of abalone larvae is another cost-effective option, as they are cheaper to produce and can be transported at high densities. A suitable larval transport method is required to minimise larval mortalities and stresses that might compromise settlement. A series of simulated experiments were conducted to optimise transportation systems of abalone (Haliotis midae) larvae. First, two potential transportation modes (Wet (W) and Dry (D) transportation) conducted at a cooler (14˚C) and average ambient (18˚C) temperatures with six replicates of each were compared with control treatments (six replicates) that were not subjected to transport, kept in water at 18˚C. Eighty hours post-initial settlement, the 14W treatment had significantly lower settlement (p=0.03) than the other three treatments (14D, 18W, 18D) and the Control. The Dry method was the prefered method to transport larvae as it is logistically simpler to employ. The second experiment investigated the effect of different stocking densities (200, 400 and 800 larvae cm-2) for the Dry method 18˚C over two transit periods (six and twelve hours) on post-transport settlement and post-settlement survival of H. midae larvae. Compared to the control, there was no difference in the number of settled larvae (p=0.368) and larvae still swimming (p=0.835) across all treatments. This suggested that H. midae larvae can be transported for twelve hours at 800 larvae cm-2 without compromising post-transport settlement or survival. This study’s results and recommendations can be used by abalone farms when there is a need to move abalone H. midae larvae between farms or to seeding sites for sea ranching. Furthermore, other researchers can use these results as a benchmark for larval transportation studies of H. midae and other abalone species. , Thesis (MSc) (Zoology) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Bajaba, Sharone
- Date: 2021-02
- Subjects: Abalone fisheries , Haliotis midae , Abalone culture
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20561 , vital:46124
- Description: Sea ranching has been identified as a viable method for enhancing the natural stock of overexploited abalone (Haliotis midae). Currently, this process involves transporting live juvenile H. midae to the seeding site where they are released onto the reef however this is both costly and logistically problematic. Transportation of abalone larvae is another cost-effective option, as they are cheaper to produce and can be transported at high densities. A suitable larval transport method is required to minimise larval mortalities and stresses that might compromise settlement. A series of simulated experiments were conducted to optimise transportation systems of abalone (Haliotis midae) larvae. First, two potential transportation modes (Wet (W) and Dry (D) transportation) conducted at a cooler (14˚C) and average ambient (18˚C) temperatures with six replicates of each were compared with control treatments (six replicates) that were not subjected to transport, kept in water at 18˚C. Eighty hours post-initial settlement, the 14W treatment had significantly lower settlement (p=0.03) than the other three treatments (14D, 18W, 18D) and the Control. The Dry method was the prefered method to transport larvae as it is logistically simpler to employ. The second experiment investigated the effect of different stocking densities (200, 400 and 800 larvae cm-2) for the Dry method 18˚C over two transit periods (six and twelve hours) on post-transport settlement and post-settlement survival of H. midae larvae. Compared to the control, there was no difference in the number of settled larvae (p=0.368) and larvae still swimming (p=0.835) across all treatments. This suggested that H. midae larvae can be transported for twelve hours at 800 larvae cm-2 without compromising post-transport settlement or survival. This study’s results and recommendations can be used by abalone farms when there is a need to move abalone H. midae larvae between farms or to seeding sites for sea ranching. Furthermore, other researchers can use these results as a benchmark for larval transportation studies of H. midae and other abalone species. , Thesis (MSc) (Zoology) -- University of Fort Hare, 2021
- Full Text:
- 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
- Giwu, Nonkonzo https://orcid.org/0000-0001-9416-7896
- 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
- Full Text:
- Date Issued: 2021-02
- 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
- Full Text:
- Date Issued: 2021-02
A framework to improve social media as a communication tool in technical vocational education and training colleges in South Africa: a case of twitter.
- Nyamanhare, Sangudzayi Innocent
- Authors: Nyamanhare, Sangudzayi Innocent
- Date: 2021-02
- Subjects: Social media , Education, Higher , Universities and colleges
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20495 , vital:46008
- Description: South Africa uses social media as a communication tool. The use of Twitter as a communication tool in Technical Vocational Education and Training Colleges (TVET) in South Africa is a crucial factor for efficient and effective communication between TVET College administration and stakeholders such as prospective students, students, prospective employers, prospective employees and the Twitter community which follow various Twitter accounts. Literature has found that TVET Colleges use Twitter in a monologic manner which promotes one-way information flow. Twitter is also used in a limited fashion and within silos within TVET Colleges that have incorporated this social media platform into their communication strategy. The main purpose of this research study was to develop a framework to improve social media as a communication tool in TVET Colleges in South Africa. The Social Media-Integration- Theory-Model was used as the theoretical framework to evaluate the use of Twitter in TVET Colleges in South Africa, thus enabling the development of critical success factors to improve the use of social media as a communication tool. The Interpretivist paradigm and qualitative research approach was chosen for this study. Netnography was used to collect the online data from Twitter that was analysed in the study. Data was collected from 36 TVET Colleges in South Africa that have a Twitter account over a one-year period (April 2019 – March 2020). After the data collection, content and thematic analysis were used to analyse the date. The study developed a framework from the analyses of tweets which incorporated the four constructs from the Social-Media-Integration-Theory-Model. The study also developed five critical success factors, namely, procuring and maintaining of ICT infrastructure; implementing a policy that guide the use of social networks for communication purposes in TVET Colleges; raising awareness on the use of Twitter as a tool for communication; intensive training to manage administration of Twitter accounts and appointing champions to promote Twitter as a communication tool in TVET Colleges. , Thesis (MCom) (Information Systems)-- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Nyamanhare, Sangudzayi Innocent
- Date: 2021-02
- Subjects: Social media , Education, Higher , Universities and colleges
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20495 , vital:46008
- Description: South Africa uses social media as a communication tool. The use of Twitter as a communication tool in Technical Vocational Education and Training Colleges (TVET) in South Africa is a crucial factor for efficient and effective communication between TVET College administration and stakeholders such as prospective students, students, prospective employers, prospective employees and the Twitter community which follow various Twitter accounts. Literature has found that TVET Colleges use Twitter in a monologic manner which promotes one-way information flow. Twitter is also used in a limited fashion and within silos within TVET Colleges that have incorporated this social media platform into their communication strategy. The main purpose of this research study was to develop a framework to improve social media as a communication tool in TVET Colleges in South Africa. The Social Media-Integration- Theory-Model was used as the theoretical framework to evaluate the use of Twitter in TVET Colleges in South Africa, thus enabling the development of critical success factors to improve the use of social media as a communication tool. The Interpretivist paradigm and qualitative research approach was chosen for this study. Netnography was used to collect the online data from Twitter that was analysed in the study. Data was collected from 36 TVET Colleges in South Africa that have a Twitter account over a one-year period (April 2019 – March 2020). After the data collection, content and thematic analysis were used to analyse the date. The study developed a framework from the analyses of tweets which incorporated the four constructs from the Social-Media-Integration-Theory-Model. The study also developed five critical success factors, namely, procuring and maintaining of ICT infrastructure; implementing a policy that guide the use of social networks for communication purposes in TVET Colleges; raising awareness on the use of Twitter as a tool for communication; intensive training to manage administration of Twitter accounts and appointing champions to promote Twitter as a communication tool in TVET Colleges. , Thesis (MCom) (Information Systems)-- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-02