Theses and Dissertations- Doctor of Philosophy

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A comparative study of the effects of problem based learning, demonstration teaching method and lecture teaching method on students' academic achievement in secondary school agriculture in Ndhiwa Sub County, Kenya
(Egerton University, 2021-10) Ogweno, Peter Oyier
A model for predicting undergraduate students’ adoption of e-learning in selected public universities in Kenya
(Egerton University, 2025) Makini, Daniel Getuno
The teaching and learning of science employ several approaches, each of which attempts to improve the quality of students’ leaming. One approach that is gaining prominence in higher educational institutions (HEIs) is e-learning. However, e-leaming adoption among students in Kenya’s HEIs is not succeeding the way it is expected because of both institutional and individual shortcomings. In this study, the University Students’ E-leaming Adoption Model (USeLAM) was developed with the aim of providing a basis for decision making in the adoption of e-leaming among undergraduate students in selected public universities in Kenya. The study adopted a cross-sectional survey design based on the Uniﬁed Theory of Acceptance and Use of Technology (UTAUT). The sample consisted of 388 undergraduate university students who answered 24 questions on a 7-point Likert Scale in the Students’ E-learning Adoption Questionnaire (SeLAQ). The SeLAQ was validated by six educational research experts at Egerton University and yielded Cronbach - Alpha reliability coefﬁcient of 0.78. Six hypotheses were tested above the 90% level of conﬁdence (p < .100) by applying the Partial Least Squares, Structural Equation Modelling (PLS-SEM) techniques. The results indicate that there were positive and statistically signiﬁcant relationships between Perfonnance Expectancy (PE) and Behavioral Intention to adopt e-learning (BI) ([3 = .15, t: 3.16, p = .002) and; between Effort Expectancy (EE) and BI (B = .18, t = 4.32, p < .001). However, Social Influence (SI) was not a statistically signiﬁcant predictor of BI ([3 = .00, t= 0.07, p = .945). On the other hand, BI Was found to be a positive and statistically signiﬁcant predictor of Actual Use Behaviour of e-learning (UB) (B = .08, t= 1.83, p = .067) while Facilitating Conditions (FC) was a negative but statistically signiﬁcantly predictor of UB (B I -.1 1, t: 1.79, p I .073). Further analysis of the effect of moderators on the relationship between predictors and outcomes of students’ adoption of e-learning was done using the PLS-Multi Group Analysis (MGA). The results indicate that students’ age (AGE), gender (GND) and internet experience (IXP) signiﬁcantly moderate students’ e-leaming adoption in varying degrees. In the ﬁnal analysis, the USeLAM accounted for 24% (R3 = .24) of the variance in Bl and 15 % (R2 = .15) of the variance in UB. In conclusion, therefore, the study underscores the signiﬁcant inﬂuence of PE and EE on students’ BI as well as that of BI and FC on students’ UB. The implications of this study extend to educational policy makers in general, and public university management, in particular, in improving e-leaming adoption in HEIs. Further, it lays the groundwork for future research in predicting e-learning adoption in Kenya’s HEIs and buttressing the multidisciplinary nature of the application of e-leaming in HEI’s.
A model for predicting undergraduate students’ adoption of e-learning in selected public universities in Kenya
(Egerton University, 2025) Getuno, Daniel Makini
The teaching and learning of science employ several approaches, each of which attempts to improve the quality of students’ leaming. One approach that is gaining prominence in higher educational institutions (HEIs) is e-learning. However, e-leaming adoption among students in Kenya’s HEIs is not succeeding the way it is expected because of both institutional and individual shortcomings. In this study, the University Students’ E-leaming Adoption Model (USeLAM) was developed with the aim of providing a basis for decision making in the adoption of e-leaming among undergraduate students in selected public universities in Kenya. The study adopted a cross-sectional survey design based on the Uniﬁed Theory of Acceptance and Use of Technology (UTAUT). The sample consisted of 388 undergraduate university students who answered 24 questions on a 7-point Likert Scale in the Students’ E-learning Adoption Questionnaire (SeLAQ). The SeLAQ was validated by six educational research experts at Egerton University and yielded Cronbach - Alpha reliability coefﬁcient of 0.78. Six hypotheses were tested above the 90% level of conﬁdence (p < .100) by applying the Partial Least Squares, Structural Equation Modelling (PLS-SEM) techniques. The results indicate that there were positive and statistically signiﬁcant relationships between Perfonnance Expectancy (PE) and Behavioral Intention to adopt e-learning (BI) ([3 = .15, t: 3.16, p = .002) and; between Effort Expectancy (EE) and BI (B = .18, t = 4.32, p < .001). However, Social Influence (SI) was not a statistically signiﬁcant predictor of BI ([3 = .00, t= 0.07, p = .945). On the other hand, BI Was found to be a positive and statistically signiﬁcant predictor of Actual Use Behaviour of e-learning (UB) (B = .08, t= 1.83, p = .067) while Facilitating Conditions (FC) was a negative but statistically signiﬁcantly predictor of UB (B I -.1 1, t: 1.79, p I .073). Further analysis of the effect of moderators on the relationship between predictors and outcomes of students’ adoption of e-learning was done using the PLS-Multi Group Analysis (MGA). The results indicate that students’ age (AGE), gender (GND) and internet experience (IXP) signiﬁcantly moderate students’ e-leaming adoption in varying degrees. In the ﬁnal analysis, the USeLAM accounted for 24% (R3 = .24) of the variance in Bl and 15 % (R2 = .15) of the variance in UB. In conclusion, therefore, the study underscores the signiﬁcant inﬂuence of PE and EE on students’ BI as well as that of BI and FC on students’ UB. The implications of this study extend to educational policy makers in general, and public university management, in particular, in improving e-leaming adoption in HEIs. Further, it lays the groundwork for future research in predicting e-learning adoption in Kenya’s HEIs and buttressing the multidisciplinary nature of the application of e-leaming in HEI’s
A study of the self-concept of children with visual handicaps in integrated and special schools in Kenya
(Egerton University, 2000-09) Muola, James Matee
Agricultural land use and its implications on household food security in Kisii Central Sub-County, Kenya
(Egerton University, 2015-09) Kumba, Janepha Kemunto
Agricultural land is an important resource for farm households as it forms the base for their livelihoods. Therefore, the manner in which households utilize this resource influences to a large extent their food security situation. This study sought to establish the impact of agricultural land use on household food security in Kisii Central sub-County, Kisii County. To achieve this objective the study focused on the following; examination of the various land use activities, assessment of the food security situation of households, establishment of the relationships between agricultural land use and household food security and finally determination of the influence of household socio-economic characteristics on agricultural land use and household food security in the study area. Agricultural land use was conceptualized as consisting of four categories namely; cash crop, food crop, fruits and vegetables and pasture and napier grass while household food security was assessed using Experience-based method. The sampling frame comprised all rural farm households in Kisii Central sub-County within the LH1, UM1 and LM2 agro-ecological zones. The sub-Location with the highest population density within each agro-ecological zone was selected and a stratified random sample of 209 respondents was picked. A structured questionnaire was used to collect data from farm household heads. Data was analyzed using the Statistical Package for Social Sciences (SPSS version 17.0). Descriptive statistics provided statistical summaries while Pearson’s Chi-square test was used to establish the relationship between agricultural land use and household food security and also analyze the influence of household socio-economic characteristics on agricultural land use and household food security. Results from the study showed that agricultural land was allocated as follows; food crop (65%), cash crop (25%) and others (10%). Most households were food secure (77.5%). Cash crop (p=0.000) and pasture / napier grass (p=0.002) were found to be significantly related to household food security. The socio-economic characteristics that had a significant influence on agricultural land use and household food security were the level of education of household head, farm size and household income. The study recommends that efforts should be put in place to boost household income through efficient utilization of the land resource in the production of both food and cash crops in order to ensure household food security within the study area.
Agrometeorological information access and adaptation to climate variability nexus: case of smallholder sorghum farmers in Busia County, Kenya
(Egerton University, 2024-09) Atsiaya, Obwina Godfrey
Significant losses among Kenyan farmers have been attributed to seasonal patterns and disruptions due to climate change. The provision of agrometeorological information as a countermeasure has been constrained by the accessibility and application of the information in adaptation to climate variability. This study aimed to improve the socio-economic welfare of smallholder sorghum farmers in Busia County by enhancing access to and application of agrometeorological information in climate risk mitigation. The study targeted small-scale farmers who are most vulnerable to climate variability and also focused on a traditional crop which has received limited attention in CSA studies. A multistage sampling technique was used to sample 423 smallholder sorghum farmers. Primary data was collected through face-to-face interviews using a pretested semi-structured questionnaire. A Multivariate Probit model was used to assess the factors influencing farmers' choice for agrometeorological information pathways. A binary logistic model was used to determine the influence of socio-economic, institutional, and climate-related factors on access to agrometeorological information. A Poisson regression method was used to evaluate the factors affecting the uptake of climate-smart agricultural practices. Finally, an Endogenous Switching Regression Model was used to assess the effect of agrometeorological information access, and socio-economic and institutional factors on adaptation to climate variability among smallholder sorghum farmers. The results indicate that sorghum farmers mostly used radio, television extension, and mobile internet as weather information pathways. Farmers were found to implement an average of 2 CSA practices. Literacy was associated with the use of television and mobile internet to access CSA information. Proximity to meteorological stations increases the probability of access to agrometeorological information by 8%. The use of Indigenous knowledge and trust in agrometeorological information increased the uptake of CSA practices by 0.119 and 0.229 units respectively. Failure to adapt CSA was associated with a lower sorghum yield with a projected mean decrease of 0.88 in yield. Similarly, adaption was associated with an income increase of 1.37. The findings of this study reveal the need for sensitizing sorghum farmers on the importance of adopting CSA practices such as drought-tolerant varieties, early maturing varieties, irrigation, water harvesting agroforestry among others to enhance their full-scale uptake, improve yield, and contribute to food and nutritional security. This can be enhanced through policies that strengthen agrometeorological information dissemination to small-scale farmers to enhance accessibility and applicability.
Analysis of county government expenditure and county economic growth in kenya
(Egerton, 2020-03) Gisore, Mose, Naftaly; Gisore, Mose, Naftaly
e modern devolution development across the globe has been in part driven by assertions of a supposed ‘economic dividend’ linked with the devolved expenditure. There is however, little empirical evidence to validate these assertions in Kenya. Most empirical studies across different countries have used different methods of analysis, different time periods and diverse techniques of measuring variable which have generated mixed conclusions and others are inconclusive. More so, in Kenya these studies do not differentiate between long-run and short-run channels through which county expenditure influences economic activities. The implication in differentiating these two effects arises for the two motives. First, there is interval between a fiscal policy action and its impact in the county economy. Second, they can have opposite effects on growth. Failure to differentiate can give erroneous results and recommendations. It is against this background that this study was carried out to analyse the long-run and short-run effect of components of county expenditure on county economic growth in Kenya using panel data set over the period 2013 to 2017. This study used the published annual data from Economic Surveys, Gross County Product (GCP) report, Statistical Abstracts and county Budget Implementation Review reports. Further, this study was informed by neoclassical augmented Ram growth accounting model as the theoretical framework. The analysis techniques that were used in this study were descriptive and inferential statistics. Employing Harris–Tzavalis (HT) test, this study tested for the panel unit root and found that all variables were non-stationary at their level except GCP per capita, human capital and non-devolved expenditure. To check if the variables have long-run relationship, this study used Kao panel test. The result for this test revealed that there exists a long-run relationship among the real GCP per capita and regressors in the model. Once cointegration was confirmed using Kao test, the long-run and error correction estimates of the panel ARDL model were obtained. The ARDL results revealed that spending on recurrent and rise in absorption rate of expenditure exerts a positive and significant effect on economic growth both in short-run and long-run hence confirming Keynesian theory in Kenya. However, capital expenditure was insignificant during the study period. Arising from the study findings, this study submits that the county authorities need to put in place policies that will improve budget allocation and execution so as to improve expenditure to capital infrastructure in counties. This is because counties typically lack infrastructures such as roads, power, water and communications that boost private productivity and consequently GCP growth.
Analysis of Extruded Ready-To-Eat Baby Foods Prepared Using Composite Flours from Orange-Fleshed Sweet Potatoes, Soybeans, and Amaranth Seeds
(Egerton University, 2023-07) Nkesiga, Jackson
There is severe food insecurity for many people who live in sub-Saharan Africa. The situation is worse for children under the age of five years who are undernourished. This is caused mainly by poverty limiting access to quality foods, as well as poor breastfeeding, and complementary feeding practices. Therefore, the purpose of this study was to develop and analyze the physicochemical properties, microbial, sensory properties, and shelf-life of extruded RTE baby foods prepared using composite flours from orange-fleshed sweet potatoes (OFSP), amaranth seeds, and soybeans. Ready-to-eat (RTE) baby foods which are conveniently distributed to the poor could be a way of mitigating this challenge. Additionally, there are advocacies for the utilization of locally available food resources for sustainable food production. Extrusion technology has been used in many parts of the world to process RTE foods. However, as with most food technologies, there are always questions regarding optimum working conditions, nutritional quality and safety, consumer outlook, and shelf stability that need to be addressed. The ingredients were optimized using the extreme vertices method of mixture design using Minitab Software. The optimum value for model verification was 57% OFSP, 24% amaranth seeds, and 19% soybeans flour, to achieve targeted values of crude protein (14%), total minerals (4.7%), and Vitamin A (813.6 Retinol Activity Equivalent μg/100g). The optimum extrusion cooking conditions were established as 90oC die temperature, 35% feed moisture content, and 400 rpm screw speed based on Box-Behnken Experimental Design of Response Surface Methodology under Design Expert Software. A completely randomized design (CRD) in a factorial experimental design was employed using statistical analysis software (SAS) for the production of extruded ready-to-eat baby foods. The results revealed that extrusion cooking and blend proportions significantly (p<0.05) affected the physicochemical properties, microbial, sensory properties, and shelf-life of extrudates. The extrusion cooking significantly (p<0.05) reduced moisture content (59.5%), protein content by 5.56%, anti-nutrient content (65.24 - 97.43%), and vitamin A content (21.33%). On the other hand, there were significant (p<0.05) increases in carbohydrate (12.31%), total minerals (10.44%), dry matter (7.06%) contents, energy value (6.38%) and energy-to-protein ratio (11.28%). Blend proportions and extrusion cooking have significant (p<0.05) positive effects on the protein quality of the extrudates in terms of in vitro protein digestibility and available lysine. The shelf-life of extrudates was found to be about 4 to 6 months. Therefore, the use of extrusion cooking techniques for OFSP, amaranth seeds, and soybeans composite flours has the potential for the production of value-added OFSP food products. These findings can be used to achieve food and nutrition security in developing countries.
Analysis of Factors Influencing Productivity and extent of Smallholder Commercialization of Green Grams and Pigeon Peas in Machakos County, Kenya
(Egerton University, 2021-04) Wambua, John Mulwa
Small farmer commercialization was an indispensable pathway towards sustainable food security based on production specialization of food crops. The common staple food crops in Mwala and Yatta sub-counties which are the main semi-arid areas in Machakos County were green grams and pigeon peas. However, the factors affecting productivity and the resultant output for commercialization are not fully understood. The main objectives were therefore to assess the extent and determinants of the levels of commercialization, estimate the factors affecting productivity of green gram and pigeon pea, determine the effects of productivity and output retention on size of marketed surplus of green gram and pigeon production and assess the factors affecting market performance. A survey method was used during data collection where 364 households and 110 grain traders were sampled. Results shown by the descriptive statistics indicated that, the percentages of subsistence and commercial oriented households, focusing on green gram were 79.1% and 20.9%, respectively. The percentages of subsistence and commercial oriented households, focusing on pigeon pea production were 87.9% and 12.1%, respectively. The mean productivity of green gram in the subsistence, semi-commercial and fully commercial farms were 11.581, 104.474 and 204.439 kilograms per hectare, respectively. Pigeon pea mean productivity was 43.334, 48.25 and 13.708 kilograms per hectare in subsistence, semi-commercial and fully commercial farms. Marketed surplus of green gram was determined by the size of landholding (4.422***), yield of green gram (0.056***), retention for seed and given away (1.027**) and production systems in agro-ecological zones (43.613***). Significant increase in pigeon pea marketed surplus was due to household’s retention for seed (2.064***) and market price of output (1.641***). In terms of market degree of competition, results showed that, few large traders of green gram, about 8.26 % accounted for 78.40% of the total volume purchased. Few large traders of pigeon pea, about 8.27 %, accounted for 72.13%. Therefore, this study concluded that, subsistence level dominated in green gram and pigeon pea production. This could have been influenced by low productivity of green gram and pigeon pea, low household marketed surplus and low market competition. Based on the results, various policy concerns were recommended for transforming subsistence-oriented production into market-oriented production focusing on green gram and pigeon pea food crops.
Analysis of microbial infections in Camel (Camelus Dromedarius) milk and implications in Kenya
(Egerton University, 2007-06) Matofari, Joseph W
Raw camel milk production and marketing chain in Kenya was investigated for microbial infections and implications. Milk samples were taken using simple random sampling method in a clustered sampling plan. There were three cluster levels, the production, and processing and market levels. Analysis of samples in the laboratory for enumeration and characterization was by standard methods as described in the methodology. Data analysis was done by Pearson correlation coefficient and chi-square. At production level, 66% of the 107 samples taken had bacterial load ranging from 103-105 colony forming units per ml (cfu/ml). Over 90% of the samples from the processing and market levels ranged from 106-108 cfu/ml. The total viable counts were higher (P < 0.05) than coliform counts at production level. There were more spores at production than at market level. All the isolated organisms did not survive temperatures above 550 C. Salmonella enterica was prevalent at production and processing level. There was no S.enterica isolation at market level. Gram-negative rods (GNR) occurred at every level of the camel milk chain with an incidence of 54% of the 254 samples taken. Gram-positive cocci (42% incidence) were highest at production level. From the study, the microbial load in raw camel milk chain increased from production to the market. GNR were the majority and included the general Escherichia, Enterobacter and Pseudomonas. S.enterica contamination of raw camel milk chain exists at production and collection level and not at the market level. The S enterica serovars involved were S. enterica Typhi and S. enterica Paratyphi C. Since camels, pastoralists and camel milk handlers may act as carriers of S. enterica in the causation web, it is recommented that another study be done to determine host specificity for the serovars identified.
Analysis of micronutrients and heavy metals of indigenous reed salts and soils from selected areas in Western Kenya
(Egerton University, 2016-11) Tsikhungu, Phanice Wangila
Most communities in Western Kenya use plant indigenous salts for cooking, medicinal and numerous uses. Typha latifolia and Cyperus rotundus reeds are widely used in Busia and Lugari regions of Western Kenya to prepare indigenous salts. The suitability of these salts and validation of micronutrients and heavy metals is unknown. The objective of this study was to assess the suitability of the indigenous reed salt used in selected parts of Western Kenya. Micronutrients and heavy metal concentrations in soil habitats, C. rotundus and T. latifolia and reed salts were determined; In addition, the effect of the various methods of processing, storage conditions and the stability of iron and iodine nutrients has been investigated. Iodometric titration (Iodine), 1, 10-phenanthroline method (Iron II), flame photometric method (Na and K) and Atomic absorption spectrophotometric method (Pb, Cd, Fe, Cr) were used for analysis. Results showed that 85% of Lugari and Busia inhabitants in Western Kenya use C. rotundus and T. latifolia reed salts. Heavy metal in the soil was of the order Fe> Cr >Pb > Cd for the dry season and Cr > Fe > Cd > Pb for the wet season both in top and sub-surface soils with higher levels in the dry season. Salt iodine was of the order Kensalt >Top-chef salt > Herbal sea salt > Sea salt > C. rotundus salt > T. latifolia and Herbal sea salt >C. rotundus salt = T. latifolia salt > Sea salt > Kensalt = Top-chef salt for Fe2+. C. rotundus and T. latifolia reed salts had higher iodine (1.1 mg/kg) than the WHO limit of 0.015 - 1.1 mg/kg , while the concentration of Fe2+ (0.9 mg/kg and 1.0 mg/kg) was below the recommended limit of 8 - 45 mg/kg. The Na: K ratio of T. latifolia salt (3.2:1) was within the recommended limit of 2.5:1 - 4:1 while that of C. rotundus salt (0.9:1) is lower. Fe, Pb and Cd levels in both C. rotundus reed and T. latifolia reed salts exceeded the WHO/FAO permissible. Effectively all iodine and Fe2+ present in the reed salts was lost within six months of storage under normal conditions of temperature and RH with more losses at elevated temperature and relative humidity. T. latifolia salt prepared using complete evaporation method and stored in LDPE container for a period not more than three months is suitable for use as table salt. C. rotundus prepared by complete evaporation method is ideal for use as a low-sodium salt.
Analysis of Risk Management Strategies among Potato (Solanum Tuberosum) Smallholder Farmers in Njombe Town Council, Tanzania
(Egerton University, 2021-11) Semeni Ngozi
Ansoff growth strategies, funding policy and the performance of universities in Kenya
(Egerton University, 2025) Wanjeri, Patriciah Murage
With the rise in reduced government funding, global competition and demand higher education, universities have adopted strategic approaches to stay relevant and enhance perfonnance. This study analysed the relationship between Ansoff growth strategies, funding policy and the perfonnance of chartered universities in Kenya and speciﬁcally examined the effect of Ansoff growth strategies comprising of market penetration, product development, market development and diversiﬁcation on performance of chartered universities in Kenya and the moderating effect of funding policy on these strategies. Strategic Fit Theory (SFT), Resource-Based Theory (RBT) and the Contingency Theory provided an understanding of how strategic alignment and resource capabilities enhance university performance. A cross-sectional research design was used for data collection and analysis. Six chartered universities were randomly selected for a pilot study from a population of 60 and a census conducted from the remaining 54 comprising 22 private and 32 public Kenyan chartered universities. Primary data was collected, from vice-chancellors or senior management ofﬁcers designated by the vice-chancellors using a structured questionnaire and SPSS V.26 was used to summarize descriptive statistics for frequencies, percentages, means and standard deviations. Inferential statistics and Pearson’s correlation analysis were computed and hypotheses tested using simple and multiple regression analysis as well as PROCESS macro. The correlation analysis results established a signiﬁcant correlation between market penetration, market development and funds generation policy and university performance (p < 0.05). Product development, diversiﬁcation strategy and funds allocation policy, however, had an insigniﬁcant correlation with performance (p > 0.05). Hypotheses test results for market penetration strategy ([3 = 0.356, p < 0.05) and market development strategy (B = 0.357, p < 0.05) reveal a signiﬁcant inﬂuence of the strategies on university performance, demonstrating their effectiveness in enhancing performance. In contrast, product development (B = 0.054, p > 0.05) and diversiﬁcation strategies (B = -0.244, p > 0.05) did not show signiﬁcant effects, implying that their contribution to performance is contextual. The study concludes that prioritization of market penetration and market development with supportive funds generation policies, signiﬁcantly improves university performance. However, product development, diversiﬁcation strategies and funds allocation policy distinctly were signiﬁcant although the joint application of Ansoff growth strategies positively enhance performance of chartered universities. Universities should therefore strengthen revenue generation and apply a mix of Ansoff growth strategies for sustained performance.
Antibacterial Activity of Chrysanthemum Cinerariaefolium (Pyrethrum) Secondary Metabolites and Green Synthesized Silver Nanoparticles
(Egerton University, 2022-08) Kosgei, Caroline Jepchirchir
The development of resistance to antibacterial agents by bacteria, drive efforts in bio prospecting for new novel compounds that can be used to target these resistant microorganisms. Plants are among natural sources of novel compounds with medicinal importance due to their desirable potency. Besides, plant phytochemicals can reduce metal ions to metal nanoparticles hence play important role in the green synthesis of nanoparticles. In the current study, bioactive compounds against selected bacteria were isolated from pyrethrum plant Chrysanthemum cinerariaefolium by carrying out bioassay-guided fractionation. The isolated compounds were characterized using 1D and 2D Nuclear Magnetic Resonance (NMR). Extracts of organic solvents and aqueous of C. cinerariaefolium were also used in the green synthesis of silver nanoparticles (Ag NPs) via reduction of silver ions present in silver nitrate. Synthesis involved mixing a fixed ratio of plant crude extracts with silver ions and storing the mixture in the dark. Observation of a color change to brown signified the formation of the nanoparticles. The nanoparticles were characterized using UV-Vis, Scanning Electron Microscopy, Transmission Electron Microscopy, EDX (energy dispersive X-ray analysis), and Fourier-Transform Infrared Spectroscopy (FTIR). The compounds isolated were (Z)-2 methyl-4-oxo-3-(pent-2-en-1-yl)cyclopent-2-en-1-yl2,2-dimethyl-3-(2-methylprop-1-en-1-yl) cyclopropane-1-carboxylate (jasmolin I), 2-methyl-4-oxo-3(Z)-penta-2,4-diene-1-yl)cyclopent-2-en-1-yl3-(E)-3-methoxy-2-methyl-3-oxoprop-1-en-yl-2,2-dimethylcyclopropane-1-carboxylate (pyrethrin II), and (Z)-2-(but-2-en-1-yl)-4-hydroxy-3-methylcyclopent-2-en-1-one (cinerolone). The compounds showed more activity on the bacteria as a mixture in the ratio of 1:1:1 than individual compounds, with MIC of 25 mg/ml against Pseudomonas aeruginosa. The compounds can therefore be used as lead compounds in drug discovery against bacteria. All the nanoparticles formed were generally spherical in shape. The smallest and largest nanoparticles had sizes of 22.8± 17.5 nm and 75.3± 19.7 nm and they belonged to dichloromethane-Ag NPs and ethyl acetate-Ag NPs respectively. The particles exhibited size-dependent activity on the selected bacteria. Safety studies on the nanoparticles and pyrethrum extracts on Vero cells showed that they were not cytotoxic hence safe for utilization in drug discovery. Pyrethrum plant therefore possesses phytochemicals that can be used in green synthesis nanoparticles. Other plants should be exploited to ascertain their ability to synthesis nanoparticles.
Antimicrobial activity and phytochemical studies of turraea abyssinica, meyna tetraphylla and leonotis mollissima
(Egerton University, 2019-11) Kinuthia, Esther Wanjiru
Due to the high bills involved in the importation of modern medicinal drugs, about 80% of the African population use traditional medicine from plants to treat common infectious diseases caused by microorganisms. The main objective of this research was to determine the antimicrobial activity of crude extracts and isolated compounds from Turraea abyssinica, Meyna tetraphylla (Abyssinian coral tree) and Leonotis mollissima (Lion’s ear) from Meliaceae, Rubiaceae and Lamiaceae families respectively. They were studied in this research due to their wide use by local communities of Kenya for medicinal remedies. Plant materials were sampled from Kirinyaga East, Narok North, Baringo South, Tharaka Nthi Maua, Laikipia University and Mau Narok in Kenya. They were identified and voucher specimen kept for reference. All the plants crude extracts showed significant antimicrobial activity on all the test microorganism (Bacillus cereus, Staphylococcus aureus, Escherichia coli,Salmonella typhimurium and Candida albicans) at a concentration of 1 mg/ml despite been sampled from different regions of Kenya. They had lower MIC (Minimum Inhibition Concentration) as compared to the Amoxil® and Doxycycline® antibiotics that were used as positive control for comparison. From Turraea abyssinica stem bark dichloromethane crude extract (52.42 g), three compounds 176 (Sitosterol, 4.60 mg), 177 (Scopoletin, 6.00 mg) and 178 [2-(1’,2’ Dihydroxypropyl)tetradecanoic acid, 5.65 mg] were isolated. Of the three compounds only compound 176 showed significant activity on Bacillus cereus, Staphylococcus aureus, and Candida albicans) at a concentration of 2.5 mg/mL to 4.0 mg/mL. Meyna tetraphylla leaves dichloromethane crude extract (45.24 g) gave compounds 179 (Phaeophytin, 9.40 mg), 180 (Enantiomer, 5.80 mg), 118 (α-Amyrin, 5.65 mg) and 60 (Sitigmasterol, 5.82 mg). The Structures of the compounds were elucidated using 1D-and 2D NMR. Experiments. Compound (179) showed significant activity on Escherichia coli and Salmonella typhimurium at a concentration of 4.0 mg/mL while α-Amyrin (118) had significant activity on Salmonella typhimurium at a concentration of 4.0 mg/mL. Leonotis mollissima leaves dichloromethane crude extract (79.69 g) yielded compounds 181 (Sederin, 7.70 mg), 182 (20-hydroxylucidenic acid D2, 7.10 mg) and 183 [(13R)-19α,13α-epoxylabda 6β(19).16(15)-dioldilactone, 21.20 mg]. Only compound (182) showed significant antimicrobial activity on Escherichia coli at a concentration of 0.4 mg/mL. This was a confirmation that the three plants contain compounds that can be isolated and used as drugs to treat various diseases including microbial infectious diseases.
Antiplasmodial and toxicity activities and characterization of chemical compounds extracted from selected medicinal plants in Uganda
(Egerton University, 2018-11) Kodi, Philip
Malaria caused by Plasmodium parasite is at the moment the one of the highest killer disease in the tropics. In developing countries, where malaria is one of the most prevalent diseases, some people still rely on traditional medicine for the treatment of this disease. In the present study an ethnobotanical survey was conducted to document antimalarial medicinal plants. In vitro antiplasmodial and in vivo toxicity activities were carried out on crude root extracts and on the isolated pure compounds from Oncoba spinosa, Acacia sieberiana and Euclea latideus. Structure elucidation was also carried out on the isolated pure compounds. The ethnobotanical survey was conducted by use of semi-structured interviews and a guided questionnaire. The characterization of the isolated compounds was determined using NMR technique only. The antiplasmodial activity was performed using a fluorescence based SYBR Green 1 assay technique on 3D7 and Dd2 Plasmodium strains. Lorke’s method was used to determine the in vivo acute toxicity of the extracts on mice. Thirty three plant species from 30 genera belonging to 23 families were documented, of these ten species (30.3 %) were recorded for the first time as antimalarial plants. Acute toxicity studies showed that all crude extracts of E. latideus and A. sieberiana had LD50 > 5000 mg/kg. The LD50 for hexane and CH2Cl2 extracts of O. spinosa were > 5000 mg/kg while the EtOAc and MeOH had 547.72 mg/kg. The EtOAc extract of O. spinosa had high activity of (IC50) 3D7: 4.69 ± 0.01 μg/mL and Dd2: 3.52 ± 0.02 μg/mL. Extracts of E. latideus had high activity (IC50) 3D7: (9.75-38.21) μg/mL and Dd2: (2.78-38.93) μg/mL. A. sieberiana extracts had the highest activity of (IC50) 3D7: (4.45-27.32) μg/mL and Dd2: (3.38-21.87) μg/mL. Isolation resulted in the identification of eight known compounds which included; three triterpenoids Lupeol, betulin, 3β-(5-methoxyferuloyl)lup-20(30)-ene; two steroids β-sitosterol, stigmasitosterol; benzoic acid and an aliphatic acid chaulmoogric acid. Betulin and β-sitosterol had the highest activity (IC50) 3D7: 3.71 and 5.51 μM, respectively. Antiplasmodial activities of the extracts (IC50: 2.76- > 50) μg/mL, pure compounds (IC50: 3.71- > 120.77) μM of the three plants and the controls (IC50: 0.0056-0.0440) μg/mL showed significance among themselves at (P < 0.05). Extracts and compounds exerted a significant (P < 0.05) decrease in antiplasmodial activity compared to the standard controls. The findings show that the crude extracts and pure compounds have got high antiplasmodial activity and lack toxicity. Therefore the local communities can continue to use the three plants for the treatment of malaria and this justifies the ethanomedicinal use of the plants for the management of malaria.
Antiplasmodial and toxicity activities and characterization of chemical compounds extracted from selected medicinal plants in Uganda
(Egerton University, 2018-11) Kodi, Philip
Malaria caused by Plasmodium parasite is at the moment the one of the highest killer disease in the tropics. In developing countries, where malaria is one of the most prevalent diseases, some people still rely on traditional medicine for the treatment of this disease. In the present study an ethnobotanical survey was conducted to document antimalarial medicinal plants. In vitro antiplasmodial and in vivo toxicity activities were carried out on crude root extracts and on the isolated pure compounds from Oncoba spinosa, Acacia sieberiana and Euclea latideus. Structure elucidation was also carried out on the isolated pure compounds. The ethnobotanical survey was conducted by use of semi-structured interviews and a guided questionnaire. The characterization of the isolated compounds was determined using NMR technique only. The antiplasmodial activity was performed using a fluorescence based SYBR Green 1 assay technique on 3D7 and Dd2 Plasmodium strains. Lorke’s method was used to determine the in vivo acute toxicity of the extracts on mice. Thirty three plant species from 30 genera belonging to 23 families were documented, of these ten species (30.3 %) were recorded for the first time as antimalarial plants. Acute toxicity studies showed that all crude extracts of E. latideus and A. sieberiana had LD50 > 5000 mg/kg. The LD50 for hexane and CH2Cl2 extracts of O. spinosa were > 5000 mg/kg while the EtOAc and MeOH had 547.72 mg/kg. The EtOAc extract of O. spinosa had high activity of (IC50) 3D7: 4.69 ± 0.01 μg/mL and Dd2: 3.52 ± 0.02 μg/mL. Extracts of E. latideus had high activity (IC50) 3D7: (9.75-38.21) μg/mL and Dd2: (2.78-38.93) μg/mL. A. sieberiana extracts had the highest activity of (IC50) 3D7: (4.45-27.32) μg/mL and Dd2: (3.38-21.87) μg/mL. Isolation resulted in the identification of eight known compounds which included; three triterpenoids Lupeol, betulin, 3β-(5-methoxyferuloyl)lup-20(30)-ene; two steroids β-sitosterol, stigmasitosterol; benzoic acid and an aliphatic acid chaulmoogric acid. Betulin and β-sitosterol had the highest activity (IC50) 3D7: 3.71 and 5.51 μM, respectively. Antiplasmodial activities of the extracts (IC50: 2.76- > 50) μg/mL, pure compounds (IC50: 3.71- > 120.77) μM of the three plants and the controls (IC50: 0.0056-0.0440) μg/mL showed significance among themselves at (P < 0.05). Extracts and compounds exerted a significant (P < 0.05) decrease in antiplasmodial activity compared to the standard controls. The findings show that the crude extracts and pure compounds have got high antiplasmodial activity and lack toxicity. Therefore the local communities can continue to use the three plants for the treatment of malaria and this justifies the ethanomedicinal use of the plants for the management of malaria.
Application of positive deviance concept to assess Amelioration strategies for environmental stresses on Smallholder dairy farms in Tanzania
(Egerton University, 2023-08) Shija, Dismas Said
Heat load, feed scarcity and disease infections are prevalent environmental stresses (ES) which either limit or reduce productivity potential of dairy cattle in the tropics. Those prevalent ES impact negatively on production performance of dairy cattle and results in a loss of livelihood benefits from dairying. Among smallholders, a few farmers (positive deviant farms (PDs)) attain consistently outstanding dairy production performance. While majority (typical farms) attain poor performance and loose benefits from dairy cattle. However, literature generally associates outperformance of PDs with husbandry practices being deployed differently from those in typical farms. Empirical evidence is lacking on association of PDs with specific husbandry practices, disease infections, lactation and growth performance. The objective of this study was to contribute to high livelihood benefits from dairying by improving productivity through learning from PDs’ ameliorative husbandry practices under contrasting stressful production environments in Tanzania. The severity of heat load stress on dairy cattle was estimated by temperature-humidity index (THI). A sample of 794 from 3800 smallholder dairy farmers benefiting from the African Dairy Genetic Gains Project was used. Positive deviants were identified based on criteria of consistently outperforming typical farms (p<0.05) in five production performance indicator variables simultaneously: daily milk yield ≥6.32 L/cow/day, energy balance ≥0.35 Mcal NEL/d, age at first calving ≤1153.28 days, calving interval ≤633.68 days and disease-incidence density ≤12.75 per 100 animal-years at risk. The study used a twofactor nested design, with farms nested within the production environment classified as lowand high-stress. Results show that dairy cattle in low-stress environment were exposed to lower heat-stress levels (68.20±0.39 THI) while those in high-stress environment were exposed to mild to moderate heat-stress levels (77.29±0.39 THI). The application of Pareto-Optimality ranking technique complemented with multiple indicator-variable sorting isolated 3.4% PDs and were fairly distributed in low- (n=15) and high-stress environments (n=12). Results reveal significant variations (p<0.05) between PDs and typical farms. Dairy cattle in PDs consistently attained better production performance in low- and high-stress environments. The management practices that differentiated PDs from typical farms were provision of larger floor spacing (13.19±1.94 vs. 6.17±0.37 m2/animal) in high-stress, cattle upgrading, and increased investment in housing, fodder, water and professional health services. These practices can be associated with amelioration of feed scarcity, heat load stresses, and disease infections, and better animal welfare status, which enabled attainment of consistent higher productivity levels in PDs. Therefore, typical farmers should learn from PDs on how to apply husbandry practices effectively to ameliorate feed scarcity, disease infections and heat load stresses.
Articulation and Phonological Impairments in the Speech of Second Language Learners in Primary School With Cerebral Palsy: A Case of St Martins Deporre’s Primaryschool, Kisumu County
(Egerton University, 2018-11) Molenje, Victor Makuto
The study sought to identify and describe the articulation and phonological impairments in the speech of 6-14 year old learners of English as a second language in primary school with cerebral palsy. Further the study also established the linguistic interventions employed by the teachers to assist the learners affected by articulation and phonological impairments as a result of cerebral palsy. Optimality theory was used to account for the impairments through mapping of competence and performance vis- a-vis input and outputs as shown in the speech samples of the respondents. Further, error analysis provided the procedural methodology for analysis of the speech samples obtained from the subjects. Data was collected from 27 subjects who were purposively sampled from the school population. For purposes of understanding the levels of severity, the subjects were put into three cohorts. A qualitative design with a triangulation strategy was adopted whereby data obtained from the subjects using picture naming tasks and focus group discussion from the teachers, was put in tables and later followed with explanations. Analysis of the speech samples collected from the subjects show the presence of the articulation impairments that include omissions, substitutions, distortions and insertions. The phonological impairments were consonant deletion, cluster reduction, syllable reduction, fronting deafrication, and stopping. Further, findings in this study show that core vocabulary and articulation therapy were the linguistic interventions employed by teachers to help remedy the impairments in the subjects. The findings of this study would be of importance and significance to three groups namely: parents, teachers and researchers. This study also offers both clinical and theoretical benefits. Clinically, data is urgently needed to inform the assessment, treatment and therapy for articulation and phonological impairments in second language learners with Cerebral Palsy. Theoretically, investigation of different varieties of English allows testing of hypothesis based on English speakers
Articulation and phonological impairments in the speech of second language learners in school with cerebral palsy: a case of st martins’ deporre’s primaryschool,primary Kisumu County
(Egerton University, 2018-11) Molenje, Victor Makuto
The study sought to identify and describe the articulation and phonological impairments in the speech of 6-14 year old learners of English as a second language in primary school with cerebral palsy. Further the study also established the linguistic interventions employed by the teachers to assist the learners affected by articulation and phonological impairments as a result of cerebral palsy. Optimality theory was used to account for the impairments through mapping of competence and performance vis- a-vis input and outputs as shown in the speech samples of the respondents. Further, error analysis provided the procedural methodology for analysis of the speech samples obtained from the subjects. Data was collected from 27 subjects who were purposively sampled from the school population. For purposes of understanding the levels of severity, the subjects were put into three cohorts. A qualitative design with a triangulation strategy was adopted whereby data obtained from the subjects using picture naming tasks and focus group discussion from the teachers, was put in tables and later followed with explanations. Analysis of the speech samples collected from the subjects show the presence of the articulation impairments that include omissions, substitutions, distortions and insertions. The phonological impairments were consonant deletion, cluster reduction, syllable reduction, fronting deafrication, and stopping. Further, findings in this study show that core vocabulary and articulation therapy were the linguistic interventions employed by teachers to help remedy the impairments in the subjects. The findings of this study would be of importance and significance to three groups namely: parents, teachers and researchers. This study also offers both clinical and theoretical benefits. Clinically, data is urgently needed to inform the assessment, treatment and therapy for articulation and phonological impairments in second language learners with Cerebral Palsy. Theoretically, investigation of different varieties of English allows testing of hypothesis based on English speakers.

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