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Effects of aflatoxin-inhibiting technologies on productivity of groundnuts in Elgeyo Marakwet and Baringo Counties, Kenya
(Egerton University, 2025-09) Buba Daffeh
Aflatoxin contamination is a major constraint to Kenya's food safety and market access, causing losses estimated at US$17.28 million annually. Groundnuts are highly susceptible to aflatoxin contamination. Both pre-and post-harvest contaminations are due to favourable conditions for aflatoxin-producing fungi. This leads to low-quality produce, low prices, health risks, and reduced income for smallholder farmers. Although several aflatoxin-inhibiting technologies have been promoted to improve groundnut productivity and quality, existing studies have not adequately documented their use, adoption levels, and impact on productivity, particularly in Elgeyo Marakwet and Baringo counties. The study specifically intended to map pre- and post- harvest aflatoxin-inhibiting technologies, identify factors influencing their adoption, assess the extent of these technologies' adoption, and determine their effects on groundnut productivity and quality. A multistage sampling technique was used to select 384 smallholder farmers across the two counties. Primary data were collected using a validated semi-structured questionnaire. Data analysis was conducted using SPSS and STATA 18. Descriptive statistics were used to examine current practices, while multivariate probit and ordered probit models assessed adoption factors and extent. An ordered probit endogenous switching regression model was applied to estimate the effects on productivity. The results posited that access to education, gender, farming experience, group membership, price of groundnuts, fertiliser use, use of improved varieties, off-farm income, and distance to market significantly influenced the uptake of a majority of aflatoxin-inhibiting technologies. Regarding adoption intensity, the findings revealed a high propensity for adoption among medium adopters as opposed to low and high adopters. Finally, the results denoted increased productivity among the medium (ATT=100kg/acre) and high (ATT=42kg/acre) adopters of aflatoxin-inhibiting technologies. The possible reason may be the selectiveness of the medium adopters when using technologies effectively. Adoption alone is enough, but selecting the most effective and timely application of the technologies is vital. For that reason, medium adopters outperform high adopters, seeing greater yield gains. Prioritise integrated approaches (e.g., resistant seeds + Aflasafe GAPs proper drying) to achieve >95% control, with subsidies for smallholder groundnut farmers. Low adopters were worse off, emphasising the need for optimal uptake to improve outcomes. The study recommends that target extension services delivery, strengthening cooperative groups, reducing the cost of the technologies, and social network programs should be prioritised. This will guide interventions aimed at improving groundnut production and boosting smallholder livelihood in Elgeyo Marakwet and Baringo counties, Kenya.
Evaluating access and use of library information resources among students at rift valley national polytechnic, Nakuru County, Kenya
(Egerton University, 2025-10) Ng’ang’a,Jessica Nyawira
Academic libraries play a critical role in supporting teaching, learning, and research within higher education. With the increasing prevalence of digital technologies, libraries now provide both physical and digital resources, including e-journals, databases, and e-books. However, students often make limited use of these resources. This gap between availability and actual use highlights the need to understand what influences students’ engagement with library materials. Without such understanding, libraries may struggle to fully support academic success. Therefore, this study aimed to evaluate access to and use of library information resources for academic success among students at Rift Valley National Polytechnic (RVNP) .The specific objectives of the study were: establish the availability of information resources at Rift Valley National Polytechnic library to meet students' information needs, examine the access and utilization of library information resources among students at Rift Valley National Polytechnic Library to fulfill their information needs and to analyze Library users’ experiences and satisfaction with the information resources at Rift Valley National Polytechnic in meeting their academic information needs. The research employed the Expectation Confirmation Theory and adopted a mixed-methods approach. The study population comprised 2025 RVNP students, from which a stratified random sample of 206 students was selected, along with one librarian for an interview. Data collection involved student questionnaires and a face-to-face interview with the librarian. Quantitative data were analyzed using SPSS with descriptive and inferential statistics, while qualitative data underwent thematic content analysis. The results indicate that print information sources remain the primary information resource in TVET libraries, with limited availability of electronic resources. The study recommends increased investment in electronic resources and digital infrastructure to remain relevant in today's technologically driven environment.
Evaluation of antimicrobial, antidermatophytic, antiproliferative and cytotoxic activity of secondary metabolites isolated from calpurnia aurea subsp. aurea (aiton) benth (l’herit) and associated fungal endophytes
(Egerton University, 2025-09) Wanga, Lucy Aketch
Antimicrobial resistance has been recognized as a significant threat to healthcare systems globally, affecting both developing and developed countries, resulting in increased rates of skin infections caused by bacterial and dermatophytic pathogens. Cancer cases have increased over the years, and existing management options often entail undesirable side effects. Medicinal plants and endophytic fungi provide alternative solutions to these challenges. This research focused on the isolation of antimicrobial, antidermatophytic, antiproliferative, and cytotoxic secondary metabolites from Calpurnia aurea subsp. aurea and its associated endophytic fungi. The leaves and stem bark of this medicinal plant were used for the isolation of endophytic fungi, while the remaining portions were used for secondary metabolite extraction using methanol. Isolated fungal endophytes were identified through molecular techniques and fermented on rice media for the extraction of secondary metabolites. All extracts from leaves, stem bark, and endophytic fungi were purified using High Performance Liquid Chromatography (HPLC) to isolate pure compounds. The structures of the isolated compounds were elucidated using 1D and 2D NMR spectroscopy, as well as Liquid Chromatography Mass Spectrometry techniques. The bioactivities (antimicrobial, antidermatophytic, antiproliferative, and cytotoxicity) of the isolated compounds were also analyzed. Nineteen endophytes were isolated, classified into the classes Eurotiomycetes, Sordariomycetes, Coleomycetes, and Agariomycetes. Together with other known compounds, five (5) previously undescribed compounds were reported, namely; quinolizidine alkaloids (46-49) and a tirucallane triterpenoid (67), additionally ten (10) phenolic compounds were reported for the first time in this study. The phenolic and quinolizidine alkaloids demonstrated antidermatophytic activity, with minimum inhibitory concentration (MIC) values ranging from 6.6 μg/mL to 300 μg/mL against Trichophyton rubrum, Trichophyton interdigitalle, Trichophyton benhamiae, Microsporum canis, and Nannizia gypsea. The cinnamic acid (65) demonstrated antimicrobial activity against Bacillus subtilis (MIC of 16.6 μg/mL), comparable to oxytetracycline (MIC 16.6 μg/mL). The phenolic compounds also exhibited antiproliferative and cytotoxic effects on KB3.1 and L929 cell lines, with compound 65 demonstrating an IC50 value of 18 μg/mL. The results of this study demonstrate the significance of C. aurea subsp. aurea and endophytic fungi as sources of antimicrobial, antidermatophytic, antiproliferative, and cytotoxic secondary metabolites, which may serve as lead compounds in drug development. Additionally, this study scientifically validates the use of C. aurea subsp. aurea in alternative medicine.
Evaluation of quality properties of eggless mayonnaise analogue prepared from chia mucilage (salvia hispanica ˆ l.) with added gum arabic from acacia senegal var. kerensis
(Egerton University, 2025-09) Odep, Apondi Lydia
Eggless low fat mayonnaise was prepared by substituting portion of the oil with gum Arabic and chia mucilage and the result of their inclusion on the physico-chemical, sensory and shelf life properties was evaluated and equated to control with 75% oil and egg yolk. Physico-chemical properties were analyzes using AOAC methods, both consumer acceptability test and quantitative descriptive analysis were done for sensory evaluation. Peroxide value was used as a spoilage indicator for shelf-life evaluation. Gum Arabic (GA) from Acacia Senegal var kerensis has been approved as an emulsifier and stabilizer in food processing industry associated with higher lipoprotein content and high-water solubility. Chia mucilage on the other hand has been approved to be incorporated as an egg yolk and fat mimetics as it is dense in polysaccharides. In this study, eggless fat reduced mayonnaise analogue was innovatively prepared using chia seeds mucilage and gum Arabic from Acacia senegal var. kerensis. Chia mucilage was used at 15, 30, 45, and 60% levels to partially replace sunflower oil and substitute the egg yolk in the mayonnaise. The findings showed that all fat-reduced eggless mayonnaises had a greater water content of 0.74 but a much lower calorie content of 493 kcal/100g and 20% fat content. The control had 0.39 moisture, 77% fat, and 784 kcal/100g of calories. These variations grew as the amount of chia mucilage substituted increased, affecting protein, pH, and carbohydrates. The amount of ash in RFM and the control did not differ significantly. The results of the sensory evaluation showed that using gum Arabic and chia seed mucilage in place of mayonnaise was acceptable. Overall acceptability showed a positive link with all the measures, with flavor showing the largest correlation (r=0.78).
Principal component analysis (PCA) loadings of 16 mayonnaise sensory qualities revealed that the first six principal components accounted for almost 66% of the variances in sensory characteristics.
With regards to texture, RFM had desirable texture in terms of firmness, adhesiveness and viscosity. The microbial counts of all samples tested were in the acceptable limits for example the total viable count<50, yeast and molds <15 while salmonella and coliforms were not detected thus rendered safe before organoleptic evaluation. The shelf life (SL) of the samples reduced with increasing temperatures and time ranging 45 to 52 days. The formulated mayonnaise analogue had lower peroxide value (PV) ranging 0.2-11.8 than control with PV 0.5-12.6 thus longer SL. This is the first time an eggless fat-reduced mayonnaise analogue prepared using chia seed and gum Arabic from Acacia senegal var. kerensis has been informed.
Fabrication and evaluation of germanium doped cesium tin triiodide perovskite solar cells
(Egerton University, 2025-09) Mogusu,Marion Kerubo
In the ever-evolving landscape of renewable energy technologies, perovskite solar cells (PSCs) have emerged as an alternative for efficient and affordable photovoltaics (PVs). The quest for sustainable energy sources, coupled with the need to eliminate toxic lead content has called for research in inorganic, cost effective and stable lead-free PSCs. In this work, tin (IV) oxide (SnO2) electron transport layer (ETL) and germanium doped cesium tin triiodide (CsSnI3-Ge) perovskite layer, incorporated with a 5mole% Ge concentration were deposited via thermal evaporation and spin coating methods respectively. In the deposition of SnO2 films, the thickness was varied, and CsSnI3-Ge films were deposited under different spin coating speeds. Optical measurements were done using the ultraviolet visible (UV-Vis) spectrophotometer while structural and morphological measurements for the perovskite layers were performed using an X-ray diffraction (XRD) and scanning electron microscope (SEM) machines respectively. Our findings show that optical properties for the 30 nm thickness ETL displayed a higher transmittance of approximately 80%, and the band gap values ranged from 3.02 eV to 3.34 eV. The CsSnI3-Ge layer deposited at a spin coating speed of 4000 rpm displayed the highest absorbance of approximately 0.77 a.u attaining a band gap value in the range of 2.85 eV to 3.35 eV which was higher than the ideal value of ~1.5 eV. Structural analysis on CsSnI3-Ge films displayed a consistent orthorhombic structure across all samples. The crystallite sizes were nearly identical, as was seen in SEM images. Generally, the perovskite film synthesized by spin coating speed of 4000 revolutions per minute (rpm) displayed higher absorbance, higher crystallinity and a relatively uniform film morphology making it the optimal layer for fabrication. Three perovskite structures of fluorine doped tin (IV) oxide (FTO)/SnO2/CsSnI3-Ge/copper (I) oxide (Cu2O)/graphite were fabricated and their current density-voltage (J-V) characteristics investigated using a solar cell simulator. From the results, the best performing cell attained a power conversion efficiency (PCE) of 2.458% with an open circuit voltage (Voc) of 0.7056 V, a short circuit current density (Jsc) of 8.868 mA.cm-2 and a fill factor (FF) of 39.27%. This output was less than expected but agrees with that of several Sn based PSCs. An optimal annealing temperature has been recommended for the SnO2 ETL for band gap control as well as an all-vacuum environment for the synthesis of Sn based perovskites. Alternative synthesis routes for Ge doping should also be explored and interface/surface passivation strategies should be considered for an improved Voc. Additionally, hall effect measurement is recommended to determine the charge carrier concentration. This study will help contribute to advancements in renewable energy technologies, research and promotion of sustainable energy solutions.