Faculty of Science

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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
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 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.
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.
Biochemical Changes and Microbial Profiles Affecting Quality and Vase Life of Cut Gladioli (Gladiolus Grandiflorus L. ‘Fado’) Following Pulsing and Cold Wet Storage
(Egerton University, 2021-04) Chore, Judith Kavulani
Floriculture in Kenya remains among the top three foreign exchange earners. Gladiolus is one of the famous cut flowers in the world. Annual losses amounting to 30,000 metric tonnes valued at USD; 166.6 is incurred by farmers due to postharvest challenges. The aimof this study was to determine the vase life and quality parameters of cut Gladiolus grandiflorus L. cv.‘Fado’ as affected by pulsing with 600 ppm 8-hydroxyquinoline sulphate plus 5% sucrose prior to wet cold storage duration(0 – 5 days). The Gladiolus were grown in the open field from corms at the Horticulture Research and Teaching Field, in the department of Crops, Horticulture and Soils, Egerton University, Kenya, during the season of September to December 2014. A two by six factorial experiment embedded in a Completely Randomized Design with four replicates was adopted using Proc GLM model in two way ANOVA. Differences in means were determined using Tukey’s test at 5% level of significance. Pulsing treatments and interactive wet cold storage durations significantly affected cut Gladiolus quality parameters including fresh weight (P< 0.0031; 11.67% increase).,dry weight (P˂ 0.0272 ;17.62% increase)., mean water uptake (P < 0.0001; 38.14% increase)., opened florets (P˂ 0.00095; 59.8% increase) and number of unopened buds (P <0.0256 ; 61-28.88% reduction). The pulsing and cold storage treatments and their interaction significantly (P˂ 0.0001., P˂0.0003.,P˂0.0001 respectively) affected the vase life of the cut Gladiolus (11.5 ± 0.0.148 days versus 4.75 ± 0.148 days; 142% increase).The pulsing treatment coupled with wet cold storage and their interactive effects significantly (P < 0.0001) affected the concentrations of the senescence biomarkers: Total Free Amino Acids, (P<.0001; 21.97% reduction)), Total Soluble Sugars (P < 0.0001; 101.16% increase) and Total Starch(P <0.0001; 309.39 % increased) on the third day in the vase compared with the control. The levels of Total Phenols, anthocyanins and microbial proliferation were also significantly affected (P< 0.0003 (104.14% increase)., P ˂ 0.0012 (26.98% increase)., P < 0.0001 (6.032% reduction) respectively) on the third day in the vase in pulsed spikes wet cold stored for 3 days.Gladiolus cut flowers can be wet stored at 3 ± 1°C up to a maximum of 4 days without any adverse effect on their subsequent vase life and quality. Small scale farmers can adopt pulsing cutG. grandiflorus cv.Fadowith subsequent storage of upto 4 days at 3 ±1 OC to manage bulking and transportation of their produce to reduce postharvest losses. This may increase domestic livelihood withenhanced foreign exchange and consequently food and job security in Kenya.Knowledge from this study will augment existing technologies in improving quality and market value of Gladiolus cut flower.
Chemical characterisation and antimicrobial activity of Compounds from some selected medicinal Kenyan ganoderma and trametes species
(Egerton University, 2020-06) Mayaka, Regina Kemunto
They are a unique group of fungi usually ignored by most fungi enthusiasts because of their typical inedibility, unfamiliar habitat and general opacity. In addition to their traditional use, contemporary research has suggested many applications for cancer treatment and boosting of the immune system. Due to increase in bacterial resistance to existing antibiotics infectious diseases have remained a major threat to human health. Hence bioactive compounds are continuously sought for disease prophylaxis and treatment. The main objective of the current work was to evaluate bioactive compounds from medicinal polypore species Ganoderma adspersum, Ganoderma applanatum, Ganoderma australe and Trametes elegans collected from Mau, Kericho area, Kabarnet and Kerio valley forests in Kenya. The dried, ground fruiting bodies of the species were extracted with methanol to give methanol crude extract, then consecutively extracted using ethyl acetate solvent to obtain an ethyl acetate extract. Fractionation and purification using column chromatography technique and further purification of some compounds was achieved on sephadex LH20. The chemical structures were determined on the basis of NMR spectroscopic data from 1H and 13C NMR, HSQC, HMBC, 1H-1H COSY and NOESY experiments, and by comparing obtained results to the values indicated in previous studies. The polypore Ganoderma adspersum yielded ergostane compounds namely ergosta-7,22-dien-3-one (54), ergosta-7,22-diene-3β -ol (55) and ergosta- 5,7,22-trien-3-ol (56). Ganoderma applanatum gave five compounds, 55, 56, 5α,8α– epidioxyergosta-6,9(11),22-trien-3β-ol (57), 5α,8α–epidioxyergosta-6,22-dien-3β-ol (58), 24- hydroxy-olean-12-en-3-one (59). The fruiting body of Ganoderma australe yielded compounds 55, 56 and 57 and Trametes elegans gave 55, 56, ergosta-7,22-dien-3,5,6-triol (60), lupeol (61) and 9,19-cycloartane-3,30-diol (62). Antimicrobial activity was assessed against important clinical bacterial and fungal strains and zones of inhibition examined using one-way ANOVA through Tukey’s PostHoc test. Most notable inhibition being against Streptococcus pyogenes 9.7 0.58 mm by compound 56, 9.0 0.58 mm by compound 55, 9.0 0.58 mm by a mixture of 57 and 58 and 8.0 0.33 mm by compound 59. It was observed that all Gram negative bacteria were insensitive to the treatment of compounds. In conclusion the study has indicated that the isolated compounds have antibacterial properties hence have demonstrated their potential as antibacterial agents. The research has also revealed that our natural indigenous forests still harbours novel natural bioactive substances and strains that needs to be investigated for novel myco-medicines in the future.
Differential Transcript and Protein Expression Profiles in Anopheles Gambiae Sensu Stricto Mosquito Larvae Exposed to Cadmium Heavy Metal
(Egerton University, 2021-11) Ngambi, Catherine Nyawira
Effects of some abiotic and biotic factors on the zooplankton community in Lake Baringo, Kenya
(Egerton University, 2014-10) Omondi, Reuben
Lake Baringo is a turbid lake that lies in a closed drainage basin of the Kenyan East African Rift Valley. The lake’s water quality has deteriorated in the recent past mainly due to sedimentation from its catchment arising from poor agricultural practices, deforestion and overgrazing. Its fishery has also declined since the 1980s and frequent lake closures to fishing activities have not alleviated the problem. This shows that there may be other critical ecological and environmental factors affecting the ecosystem. To understand problems facing the lake, there is need for well-coordinated and comprehensive ecological investigations considering the complexity of the ecosystem. Zooplankton is important in energy transfer from primary producers and constitute a significant component of the diets of the juveniles and some adults of many fish species. The objective of the present study was to determine the effect of some physical, chemical and biological factors on the spatial and temporal distribution, abundance and biomass of zooplankton in Lake Baringo. Stratified random design was used to allow for statistical comparison between zooplankton abundance and biomass at different stations and months with environmental factors using Analysis of Variance (ANOVA). The relatively stable environmental factors across the sampling stations in the lake were attributed to its small size, shallowness and the daily mixing by wind action. A total of 39 species of zooplankton belonging to Rotifera, Cladocera and Copepoda groups were recorded. The results indicate that distribution, diversity, abundance and biomass of zooplankton were influenced by environmental factors especially depth, conductivity and turbidity. Diel vertical distribution of zooplankton was the reverse of what is reported from clear lakes with organisms congregating to the surface during the day and descending to the bottom at night. Investigations into the diet of three main fish species in the lake showed that Oreochromis niloticus baringoensis mostly depended on algae, Clarias gariepinus depended on fish while Protopterus aethiopicus thrives on molluscs as their dominant food. The growth performance of the once dominant endemic fish, O. niloticus baringoensis could be affected by the high turbidity, which reduces primary production. Moreover, reduced clarity hampers the feeding success of this visual feeding fish and has decreased macrophytes to near extinction. There is urgent need for rehabilitation of Lake Baringo and the study recommend afforestation and reduction of livestock numbers in the catchment as some of the ways of reducing soil erosion and sediment input in the lake. The results of the study may be used as an important tool for the detection of stability and trophic levels of the ecosystem and to provide data for models on maximal resource production of the lake.
Effects of Structured Nutrition Education on Maternal Breastfeeding Self-Efficacy, Perceptions and Exclusive Breastfeeding Duration in Kiandutu, Thika-Kenya
(Egerton University, 2017-11) Mituki, Dorothy M.
Despite the fact that the overall benefits of exclusive breastfeeding (EBF) for the first half of infancy have well been established, especially for mother-infant pairs in low social economic status, the rates are low in Kenya. The study aimed at evaluating the effects of structured nutrition education on maternal breastfeeding self-efficacy, perceptions and EBF duration. A cluster randomized controlled intervention was carried out. The intervention included education sessions with the nutritionist at the health centre, monthly home visits by the community health workers (CHWs) plus the usual care at the Maternal Child Health (MCH) clinic. The intervention utilized the national manual on maternal infant and young child nutrition (MIYCN) and emphasized conditions infants were susceptible to with early complementary feeding, simple messages on the importance of positive attitude and making a decision to EBF, as the best choice for mothers, breastfeeding within the first hour of delivery; dietary diversity and importance of proper attachment. Monthly home visits were made by CHWs postpartum to encourage mothers to EBF and answer mothers‘ questions. Anthropometric and feeding data for the infants was collected at 6, 10, 14 and 24 weeks. Maternal anthropometric measurements (weight and height), and breastfeeding perceptions were collected at recruitment (28 weeks) at 38 weeks and 14 weeks postpartum while the feeding data was collected monthly. The primary outcome, duration of EBF for mothers in the intervention (n=256) compared to those in the comparison group (n=176) was examined. Secondary outcomes of the study (breastfeeding self-efficacy, and perceptions) were analysed in relation to involvement in the structured nutrition educational intervention or not. Analysis was done on intention to treat basis. A statistical significance difference was found between the two groups in regarding to EBF duration at 24 weeks log rank= 20.277, (1, n=314) p < 0.001. Intervention group (45.3%) compared to the comparison group (15.0%). The end line (p=0.001) maternal breastfeeding self-efficacy positively predicted EBF duration. Out of the four perceptions, only perceptions on barriers to EBF at end-line (p<0.05) positively predicted the outcome variable. Bivariate analysis yielded two socio-economic significant predictive variables of EBF duration, education level of mothers; (OR 4.75, 95% Cl 1.58-14.30, p=0.006) and household food security (OR 0.03, 95% Cl 0.01-0.09 p=0.001). Being in the intervention group, increased the likelihood of having higher BSE (Log odds 1.41, 95% Cl 0.08-2.75) and EBF duration (Log odds 10.32, 95% Cl 4.26-16.39) Structured nutrition education should be implemented to ensure mothers gain confidence and are able to deal with barriers associated with EBF for the first six months.
Evaluation of anti-diabetic effects of phytochemicals from urtica dioica (stinging nettle),salvia officinali(sage),Psidium(Guava) and citrus limon(lemon) using an experimental mice model
(Egerton University, 2020-08) Kanana, Faith Mbiti
Diabetes mellitus affects millions of people Worldwide. In developing countries, diabetes mellitus causes signiﬁcant morbidity and mortality to both children and adults. Although extensive research has been conducted on diabetes mellitus, effective treatment has not yet been reported. Oral anti-diabetic drugs and insulin used in clinical management are expensive, unavailable or have side effects. Therefore, there is need for safer and effective bio-active drugs from medicinal plants. The aim of this study was thus to investigate the anti- diabetic efficacy of phytochemicals from Urtica dioica, Salvia oﬂicinalis, Psidium guajava and Cirrus limon leaf extracts. Three months old fresh leaves of the plants were collected from Egeﬂon University’s Botanical Garden for extraction of phytochemicals. Methanol Was used as the primary solvent for extraction. The resultant plants extracts were partitioned with Water, ethyl acetate and hexane and concentrated using a rotary vacuum evaporator to obtain ethyl acetate, hexane, and aqueous crude extracts. Diabetes was induced in the experimental mice using a single intraperitoneal injection of alloxan monohydrate at a dose of 200 mg/kg body Weight. The crude extracts Were subjected to preliminary in vivo bio-assays for 7 days Where they Were administered orally to experimental mice. Ethyl acetate extract of S. oﬂicinalis and methanol extract of C. limon did not reveal any anti-diabetic effect while the aqueous extract of S. Qﬂicinalis showed signiﬁcant hypoglycemic effect, p< 0.05 compared to other extracts. It Was, therefore, subjected to further hypoglycemic studies Where fasting blood sugar and live Weights of various groups were monitored at intervals of 72 hours for 15 days. There was a signiﬁcant drop in blood sugar levels of the groups treated With S. ojﬁcinalis aqueous extract at 400 mg/kg and 600 mg/kg dosage levels from 452.00 zk 11.13 Mg/dl and 431.00 :1: 10.65 Mg/dl to 256.33 :1: 5.12 Mg/dl and 256.67 :1: 8.74 Mg/dl and Weight gain improvement from 28.05 i 0.39 g and 27.38 i 0.52 g to 29.32 i 0.42 g and 28.55 zt 0.38g respectively compared to controls, p< 0.05. Histopathological analysis of liver and kidney tissues obtained from euthanized mice did not reveal any significant changes compared to the controls. This indicated that the extracts did not confer adverse effects on these tissues. Phytochemical tests of the extracts revealed presence of flavonoids, sterols, saponins, tannins, alkaloids, and triterpenes. Flavonoids and triterpenes particularly have been documented to possess anti-diabetic effects on alloxan induced mice. Results from this study indicate that U. dioica, S. ojjﬁcinalis, C. limon and P. guajava extracts are potential anti-hyperglycemic and can be used in modulating blood glucose with exception of ethyl acetate extract of S. oﬂicinalis and methanol extract of C. limon.
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.
Haematological and tissue enzyme changes in a sheep model infected with Trypanosoma brucei rhodesiense
(Egerton University, 2017-11) Mavura, Hawa
Control and management of human African trypanosomosis faces many challenges including limited available drugs that are stage specific and also toxic, treatment failures and post treatment CNS and cardiac pathology which might be fatal. Because of ethical considerations, trypanosomosis and drug trial studies are conducted using animal models which have drawbacks. It is therefore important to develop models that can address the current drawbacks and also develop enzymatic disease staging markers to detect CNS and cardiac involvement in order to institute correct choice of trypanosome drugs and/or use of adjunct to mitigated conditions. The current study evaluated a sheep model infected with Trypanosoma brucei rhodesiense as a cheap and reliable model of human trypanosomosis. In addition the model was used to asses clinical signs, haematological changes and the use of total and isoenzyme CK and LDH levels in serum and CSF as markers of cardiac and staging of CNS infection, respectively. Eight sheep were infected with 1 × 10 4 T.b rhodesiense and two were uninfected controls. Blood was collected from the ear and jugular vein for parasitemia and for haematological and biochemical changes, respectively. CSF was also collected for cells and biochemical changes while total CK and LDH plus their respective isoenzymes were done by using starch gel electrophoresis and their quantification by a UN-SCAN IT densitometry. Infected sheep developed acute infection accompanied by clinical signs and haematological changes that mimicked infections in humans, including loss of body weight and fever.The infection was also characterized by an increase in MCH and MCHC. However, there was a decline in the levels of PCV, HCT, Hb, MCV and RBC counts. All parameters however recovered to control levels after treatment.This study also showed an increase in total protein, total LDH and total CK activities in both serum and CSF of infected compared to uninfected sheep. At the same time LDH and CK total enzyme and isoenzyme changes indicated cardiac involvement suggesting the diagnostic potential of the enzymes. However the infection did not develop a chronic CNS infection since following humane treatment of the infected sheep with berenil this resulted in cure of the infection and thus did not lead to late stage CNS infection. The study indicated that the T. b.rhodesiense sheep model can be a useful animal model of human African trypanosomosis. However, the study needs to be repeated using a less virulent or low dose of trypanosome to ensure the disease develops to the chronic stage.
In silico drug design and characterization of selected active compounds from sapium and salvia genus as anti-cancer agents using molecular docking and molecular dynamics simulations
(Egerton University, 2025) Ouma Russell Ben Omondi
Extensive research projects have been performed to better understand the genetic landscape and tumour development of localized and metastatic breast cancer (BC) and prostate cancer (Pca). In this study, computational studies and in vitro analysis were conducted before in vivo analysis to provide predictive insights into potential mechanisms and mitigate risks and hazards associated with animal experiments. Through molecular dynamics, ligand binding within the binding pocket of a ligand-protein was investigated using parameters such as root mean square deviation (RMSD) and root mean-square ﬂuctuation (RMSF), along with molecular dynamics simulations that tracked ligand-receptor interactions over a 200-nanosecond (ns) simulation trajectory. This study presents studies of a far less explored ellagic acid (EA), [20-3H] phorbol- l2, l3-dibutyrate ([3H] PDBu), and [20-3H]-l2-deoxyphorbol-13-isobutyrate ([3H] DPB) key metabolites from the genus Sapium and compares with the widely studied salvianolic acid B (Sal B) from Salvia. The molecular interactions of these compounds with the proteins were determined using molecular docking and molecular dynamics simulation. The molecular dynamics simulations revealed that salvianolic acid B exhibited binding afﬁnities of -38.49 kJ/mol, -28.87 kJ/mol, and -33.05 kJ/mol when targeting DNA lyase, topoisomerase II alpha, and mTOR, respectively. These docking scores were comparable to those of EA, exhibiting a binding afﬁnity of-36.40 kJ/mol, -27.20 kJ/mol, and -31.80 kJ/mol when targeting DNA lyase, topoisomerase II alpha, and mTOR, respectively. Based on this, Sal B showed greater negative binding afﬁnity indicating kinetically stable ligand-protein interactions. The dominance of the ligand- protein interactions indicate the signiﬁcance of synergies such as the electrostatic interactions, Van der Waals forces and hydrogen bonds. Sal B had docking scores of - 46.86 kJ/mol and -27.24 kJ/mol respectively when docking NUDT5 and androgen receptor (AR). The ﬁndings of the molecular dynamics simulation also showed that the interaction of Sal B- protein had a stable RMSD with an average of l.5- 2.0 Angstroms (A). These in-silico results are indicative of biologic potential of Sal B as an anticancer agent. Evaluation of the RMSD values indicated that there were structural changes with time before reaching a plateau. This indicated a ﬁxed ligand binding site. The RMSF plot also provided infomiation regarding the ﬂexibility of the protein residues. In the studied ligand-receptor complexes, the RMSF values ﬂuctuation did not exceed 2 A, showing that the protein residues remained relatively rigid.
Influence of nutrition and value chain governance on enterprise performance in smallholder pig production in Kenya
(Egerton University, 2019-01) Muthui, Jonah N.
Smallholder pig production in Kenya is a popular livelihood strategy but is faced with serious challenges, key among them being high cost and poor quality of feeds and weak value chain governance which result in high enterprise costs. To minimise losses, smallholders use locally available alternative feed resources (AFR) which coud be impacting negatively on performance. This study investigated feeding decisions, bio-economic benefits of using alternative feed resources (AFR), benefits of exogenous dietary enzymes and the influence of value chain governance features on competitiveness of smallholder pig enterprises. A proportionate to size purposive sampling procedure was used to select 144 enterprises in Busia, Nakuru and Kiambu Counties using the snowballing method. Interviews were conducted using pretested structured questionnaires to collect data on enterprises. Feeding experiments were set up at Egerton University Tatton Agricultural Park. Mixed analytical methods including decriptive and inferential statistics and regression analysis were applied using SAS systems, SPSS and STATA statistical software. The study concluded that the daily allowances of dry matter, crude protein and metabolisable energy associated with AFR were significantly lower (p ≤ 0.05) than the recommended daily allowance. Sows fed on AFR had delayed puberty, lower litter sizes and longer farrowing intervals compared to sows fed on commercially compounded feeds (p ≤ 0.05). Inclusion of cold pressed canola meal and rice polishing in weaned piglet diets resulted in higher (p ≤ 0.05) metabolisable energy: average daily gain (ME: ADG) and feed cost: average daily gain (FC:ADG) ratios. Inclusion of rice bran in piglet diets did not offer any bio-economic benefits. Inclusion of a dietary multi-enzyme complex resulted in higher (p ≤ 0.05) apparent digestibility of Nitrogen, energy and feed cost efficiency. Finisher diets lower in protein (14.9 -16%) and higher in dietary fibre resulted in higher (p ≤ 0.05) killing-out percent, loin eye area and villous height. Cold pressed canola diet resulted in higher (p ≤ 0.05) back fat thickness and larger (p ≤ 0.05) crypt depth. Value chain governance features including technology adoption product quality and market access had significantly (p ≤ 0.05) positive influence on enterprise competitiveness. The quality of work in pig enterprises negatively (p ≤ 0.05) influenced competitiveness of pig enterprises. The study recommend capacity building for farmers and extension staff, animal feed testing and use of biotechnology to improve feeding decisions. Further research into waste conversion technologies, the effects of dietary components such as lipids, phenolics on carcass and digestive tract are recommended.
Integrating fuzzy and bipolar fuzzy metrics into digital topology for enhanced image analysis
(Egerton University, 2025) Gathigi Stephen Macharia
Digital topology provides a mathematical foundation for analysing discrete image structures. It is considered to be a very critical part of processing image data because it provides us with information about the properties of images. The approaches to digital topology have been studied to great detail by several researchers and each approach has been seen to have advantages and limitations. In general, the approaches that exist, which are the Graph theoretic and axiomatic methods, are both found to stmggle when it comes to handling the imprecision that is present in images and other digital structures. This is because such methods do not account for dual uncertainty. Consequently, this limits their effectiveness in real-world applications. While fuzzy and bipolar fuzzy set theory provide ﬂexible tools for addressing these limitations, their integration into digital topology remains underdeveloped. This study addresses this gap by developing a mathematical framework that extends traditional digital topology into fuzzy and bipolar fuzzy logic for image analysis. The research formalises fuzzy and bipolar fuzzy metric spaces on the digital plane, and attempts to integrate these bipolar fuzzy metrics into digital topology. Topological properties, including connectedness, adjacency, and surroundness, are also extended into the fuzzy and bipolar fuzzy domain. This has been done in order to ensure mathematical consistency in representing digital images. Additionally, the study proposes new similarity, distance, and entropy measures to reﬁne the important aspects of image analysis such as image segmentation. Through computational implementation, the ﬁndings contribute to a more realistic approach to image segmentation that is also mathematically sound. This research greatly improves the applicability of digital topology in image processing technique since it establishes a framework that handles uncertainty in digital images. The study’s outcomes will pave the way for deeper analysis of digital images and hence strengthen the intersection of topology, fuzzy mathematics, and artiﬁcial intelligence.
Molecular characterisation of tsetse-endosymbiont interactions in Kenyan populations of glossina austeni and glossina pallidipes tsetse flies
(Egerton University, 2014-03) Wamwiri, Florence Njeri
Tsetse flies (Diptera: Glossinidae), which are the major vectors of human and animal trypanosomes, harbour bacterial gut symbionts Wigglesworthia glossinidia, Wolbachia pipientis and Sodalis glossinidius in close association with trypanosomes. The objective of this study was to determine the prevalence, temporal variation and strain diversity of these endosymbionts in G. austeni and G. pallidipes from the Kenyan coast. The co-relation between symbiont and trypanosomes infection was also assessed, in order to provide insight into tsetse-symbionttrypanosome interactions. Fly age was estimated using ovarian ageing and wing fray analysis. Symbiont infection was determined using symbiont-specific assays targeting wsp, 16s rRNA, GPO1 genes. Trypanosome infection was also determined by dissection and generic primers. The diversity of infecting symbiont strains was evaluated by wsp typing, multi-locus strain typing (MLST) and variable number of tandem repeats (VNTRs) methods. Trypanosomesymbiont co-infection was assessed in both natural and experimental populations and in ampicillin-treated flies. The results showed that although Wolbachia infected all G. austeni individuals sampled, no G. pallidipes sampled was Wolbachia-infected. Sodalis infection was found in 3.7% of G. austeni and in 15.9% of G. pallidipes sampled. Wolbachia strains were found to be homogenous based on wsp typing, but slight variations were detected using MLST. In addition, multiple Sodalis strain variations were detected. Age grading revealed that female flies of both species had comparable longevity; but that male G. pallidipes analysis had longer lifespan than G. austeni. Trypanosome infection rates of 12.8% and 9.6% were recorded in G. austeni and G. pallidipes respectively, of which 45.6% were T. congolense infections. In natural populations, Sodalis-trypanosome co-infection was less than 4% in both species, predominantly with T. congolense or T. simiae trypanosomes. The level of significance of the association between trypanosome and Sodalis infection was found to differ depending on fly species and trypanosome species. This study concludes that there is marked heterogeneity in gut microfauna in terms of infection incidence, strain diversity and temporal infection patterns in natural tsetse populations. Additionally, infection with a particular symbiont does not appear to influence either the presence of the other symbionts or trypanosome infection. This study highlights interspecific differences in tsetse-symbiont-trypanosomes tripartite interactions that proposed symbiont-mediated tsetse control interventions should take into account.

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