RP-Department of Biochemistry and Biotechnology
Permanent URI for this collection
Browse
Recent Submissions
Item Cholera in Zambia: Explanatory Factors and Mid-term Impact of the Sustainable Development Goals(AJRID, 2024) Siamalube, Beenzu; Ehinmitan,Emmanuel; Ngotho,Maina; Onguso, Justus; Runo, StevenCholera, a highly contagious disease caused by Vibrio cholerae, poses a severe public health threat, especially in low- and middle-income countries with limited access to clean water and adequate sanitation. Symptoms such as acute watery diarrhoea, vomiting, and muscle cramps can lead to rapid dehydration, and without timely treatment, cholera can be fatal. Globally, cholera incidence has increased significantly, with World Health Organisation data showing a rise from 223,370 cases in 2021 to 472,697 in 2022, with the number of affected countries growing from 35 to 47. In Zambia, cholera outbreaks are recurrent, particularly during the rainy season, with 30 outbreaks recorded between 1977 and 2018. Fishing camps in rural areas and densely populated peri-urban areas, particularly in the Copperbelt and Lusaka provinces, report the highest incidences, attributed to inadequate waste management and poor drainage. This study investigates the factors influencing cholera dynamics in Zambia, focusing on climate variability, population density, and water and sanitation infrastructure. This study employs a mixed-methods approach, analysing historical cholera records, climate data, and socioeconomic factors since 1977. The article seeks to identify correlations between environmental and socioeconomic variables and cholera incidence, to guide effective public health strategies. The findings aim to support Zambia’s efforts to eliminate cholera within its borders by 2025, aligned with the Multisectoral Cholera Elimination Plan and Vision 2030Item Evaluation of Granular Formulated Strigolactone Analogs for Striga Suicidal Germination(John Wiley & Sons, 2024) Jamil,Muhammad; Margueritte,Ouedraogo; Yonli,Djibril; Jian You Wang; Navangi,Lynet; Mudavadi,Patrick; Patil,Rohit H.; Bhoge,Satish Ekanath; Traore,Hamidou; Runo,Steven; Al-Babili,SalimBACKGROUND: Striga hermonthica, an obligate root parasitic weed, poses a significant threat to cereal production in subSaharan Africa. Lowering Striga seed bank in infested soils is a promising strategy to mitigate infestation levels. The dependency of Striga seed germination on strigolactones opens up the possibility of a ‘suicidal germination’ approach, where synthetic germination stimulants induce lethal germination in the absence of a host. Implementing this approach requires active germination stimulants with a suitable formulation for field application. Here, we describe the development of slowreleasing granular formulation of two potent germination stimulants ‘Methyl Phenlactonoate 3’ and ‘Nijmegen-1’ and the assessment of their activity under Laboratory, greenhouse, mini-field, and field conditions. RESULTS: Under laboratory conditions, the granular formulation of either of the two germination stimulants (1.25 mg per plate, corresponding to 0.09 mg a.i.) induced Striga seed germination at a rate of up to 43%. With 10 mg granular product (0.75 mg a. i.) per pot, we observed 77–83% reduction in Striga emergence under greenhouse pot conditions. Application of the formulated stimulants under artificially or naturally infested fields resulted in approximately 56%, 60%, and 72% reduction in Striga emergence in maize, sorghum, and millet fields in Kenya and Burkina Faso, respectively. CONCLUSION: Our findings on the newly designed granular formulation of Methyl Phenlactonoate 3 and Nijmegen-1 reveal encouraging prospects for addressing the Striga problem in Africa. These findings underscore several significant advantages of the formulated stimulants, including suitability for the African agricultural context, and, most importantly, their effectiveness in reducing Striga infectionItem Cell Wall Dynamics in the Parasitic Plant (Striga) and Rice Pathosystem(MPMI, 2025) Barminga Damaris; Mutinda Sylvia; Mobegi Fredrick M.; Kibet Willy; Hale Brett; Anami Sylvester; Wijeratne Asela; Bellis Emily S.; Runo StevenIn the plant-plant pathosystem of rice (Oryza sativa) and the parasitic plant Striga hermonthica, cell walls from either plant are important defensive and offensive structures. Here, we reveal the cell wall dynamics in both Striga and rice using simultaneous RNA sequencing. We used weighted gene co-expression network analysis to home in on cell wall modification processes occurring in interactions with a resistant rice cultivar (Nipponbare) compared with a susceptible one (IAC 165). Likewise, we compared the cell wall dynamics in Striga infecting resistant and susceptible rice. Our study revealed an intense battlement at the Striga-rice cell walls involving both parasite (offense) and host (defense) factors, the outcome of which makes the difference between successful or failed parasitism. Striga activates genes encoding cell wall-degrading enzymes to gain access to the host, expansins to allow for cell elongation, and pectin methyl esterase inhibitors for rigidity during infection. In the susceptible host, immune response processes are not induced, and Striga-derived cell wall-degrading enzymes easily breach the host cell wall, resulting in successful parasitism. In contrast, the resistant host invokes immune responses modulated by phytohormones to fortify the cell wall through polysaccharides and lignin deposition. Through these processes, the cell wall of the resistant host successfully obstructs parasite entry. We discuss the implications of these findings in the context of practical agriculture in which cell wall modification can be used to manage parasitic plants.Item Pre- and Post-Attachment Resistance Response of Popular Western Kenya Maize Hybrids to Parasitism by Witchweed (Striga(wiley, 2024) Odero Calvins Okoth; Kibet Willy; Oduor Richard Okoth; Dida Mathews Mito; Runo StevenStriga hermonthica (Delile) Benth is a root parasitic weed that causes significant crop losses in cereals in the sub-Saharan Africa. Host resistance is a sustainable management approach; however, Striga resistance in maize is rare. Furthermore, hybrids, preferred for high yield and other agronomic traits are more susceptible than local landraces. We sought to determine the responses of popular maize hybrids against Striga infection using in vitro germination and rhizotron assays. We screened 16 maize hybrids commonly cultivated in Kenya against two common Striga ecotypes (Kibos and Alupe) by measuring their (i) ability to induce the germination of S. hermonthica seeds in an in vitro system (pre-attachment resistance) and (ii) ability to resist the attachment and establishment of effective parasitism (post-attachment resistance). Results showed that two maize hybrids H614D and H629 exhibit both pre- and post-attachment resistance comparable to a Striga resistant landrace KSTP'94 used in this study as a resistant check. Other hybrids displayed moderate Striga resistance; DK8031 (pre-attachment resistance) and Duma43, phb30G19 and WH507 (postattachment resistance). Striga virulence, defined as aggressiveness of the parasite— measured by response to germination and host colonisation, was higher for the Kibos ecotype compared to the Alupe ecotype. However, the resistance pattern of maize genotypes remained consistent across the different Striga ecotypes. These results provide a basis for informed decisions on cultivation of various maize hybrids under Striga infestation in western Kenya.Item Prevalence, Associated Risk Factors and Antibiotic Susceptibility Patterns of Common Diarrheagenic Bacteria Isolated from Food Handler Populations in Nairobi, Kenya(asiapacificpublishers, 2025-04) Gitau, Daniel Karuoya; Maingi, John M.; Gitau , George; Muasya, Daniel; Karugu , Mercy; Kiminda, Ernestina; Njeru, John MwanikiBackground:Diarrheal disease is estimated to cause 29% of illness among adults and is also the major cause of illness and hospitalization for children under 5 years of age. Despite the high cases of food borne illness, there is still low reporting, diagnosis and recording of infection rates. Food handlers play a significant role in food borne pathogens transmission due to their direct contact with food and drinks. This study aimed at determining the prevalence, associated risk factors and antibiotic susceptibility profiles of common diarrheagenic bacterial pathogens among food handler populations in Nairobi.Materials and Methods:A cross-sectional study was conducted by systematically enrolling consenting food handlers working in the hospitality industry in Nairobi into the study. Self-reported data focusing on Water, Sanitation and Hygiene (WASH)-related behaviors of the participants was collected through a structured, closed-ended questionnaire. Stool samples were obtained and bacteriological analysis performed using conventional stool culture methods. The recovered bacterial isolates thereafter underwent Antibiotic Susceptibility Testing (AST) using the disk diffusion method to determine their resistance profiles. To assess the factors associated with antimicrobialresistance, Poisson regression modeling (univariate and multivariate) was used on the count outcome (number of antimicrobials to which a sample was resistant).Results:A total of 231 isolates were confirmed as the pathogens of interest after biochemical testing: Escherichiacoli(178/885), Klebsiellapneumoniae (47/885), Salmonellaspp (5/885) and Shigella(1/885). Almost all the recovered isolates showed resistance to erythromycin (97%) while about 81% exhibited resistance to amoxicillin-clavulanic acid.There was intermediate resistance seen against cefotaxime (40%), cefepime (33%), cefuroxime (53.75%) and gentamicin (27%). Low level of resistance was found against meropenem (1%), ciprofloxacin (10%) and chloramphenicol (9%). Of the E. coliisolates obtained, 41 (23%) were multi drug resistant and 2 (1.12%) were both Multi Drug Resistant and Pan Drug Resistant (PDR). Only 1 Klebsiella sppisolate was MDR. None of the Salmonella sppand Shigella sppwas found to be Multi-Drug Resistant. Regular handwashingwas found to be the most significant risk factor for infection with a pathogenic bacteria (p<0.05: 95% CI: [-0.339-0.127]). Food handlers who practiced regular handwashing had significantly lower antimicrobial resistance counts based on their incident rate ratios (IRRs) (IRR = 0.85, p = 0.029). Conversely, wearing hairnets (IRR = 2.55, p < 0.001) and working in informal eateries (IRR = 1.51, p = 0.005) or middle-level restaurants (IRR = 1.43, p = 0.008) were associated with higher resistance counts.Conclusion:Afairly high prevalence of diarrheagenic bacterial pathogens (26%) was found among the food handler population. There was also notably high levels of antibiotic resistance to commonly used drugs for diarrhea management, with medium and high levels of drug resistance to common first line drugs like erythromycin and amoxicillin-clavulanic acid being observed. Efforts should be made to improve access to clean water for both personal and hotel use for the sake of proper food hygiene practices such as handwashing. Sensitization for increased awareness on the importance of proper handwashing practices should also be done more regularly at the workplaces. All workers should also be medically examined appropriately and regularly before certification and advised to seek proper treatment in case of gastrointestinal illness to ensure proper administration of antibiotics for treatment to reduce potential cases of drug resistance.Item Genetic Diversity of Aedes Aegypti Populations from Kisumu and Busia Counties, Western Kenya, and Their Vector Competence for Chikungunya Virus(PLoS ONE, 2025) Anyango Victor O.; Langat Solomon; Mulwa Francis; Mutisya James; Koka Hellen; Okoyo Collins; Chepkorir Edith; Konongoi Samson; Karanja Anncarol; Kerubo Glennah; Sang Rosemary; Lutomiah JoelAedes aegypti (Ae. aegypti) is the primary vector of several arboviruses, including dengue virus (DENV), chikungunya virus (CHIKV), yellow fever virus (YFV), and Zika virus (ZIKV). This vector is widespread globally in tropical and subtropical areas but also found in temperate areas. Kenya experienced its first chikungunya outbreak in Lamu County in 2004, followed by subsequent outbreaks in Mandera in 2016 and Mombasa in 2017. Despite the presence of Ae. aegypti in Kisumu and Busia counties, no outbreaks of chikungunya fever have been reported in these two western Kenya counties. To investigate this phenomenon, we collected Ae. aegypti mosquitoes from the county headquarter towns of Kisumu and Busia. The mosquitoes were reared under controlled laboratory conditions, and their genetic diversity assessed using COI gene sequences. Additionally, neutrality tests, including Tajima’s D and Fu’s FS, were subsequently performed to infer evolutionary dynamics. The mosquitoes were then evaluated for their ability to transmit CHIKV by challenging laboratory-reared F1 generations of field-collected mosquitoes with an infectious blood meal containing CHIKV. Genetic analysis revealed the presence of both Ae. aegypti subspecies, (Ae. aegypti aegypti [Aaa] and Ae. aegypti formosus [Aaf]) in the two western Kenya counties, with Aaf being dominant (19:8 for Kisumu samples and 25:6 for Busia samples). The populations exhibited high haplotype diversity (0.96011 in Kisumu and 0.93763 in Busia) and low nucleotide diversity (0.00913 in Kisumu and 0.00757 in Busia), indicating significant genetic polymorphism at the loci examined. Additionally, negative neutrality tests, including Tajima’s D (-1.87530 for Kisumu and -1.09547 for Busia) and Fu’s FS (-10.223 for Kisumu and -15.249 for Busia), coupled with a smooth mismatch distribution, suggest that recent evolutionary events may have significantly shaped the genetic structure of these populations. The assessment of vector competence of Ae. aegypti populations from Kisumu and Busia counties revealed their capacity to support CHIKV transmission. Specifically, we demonstrated infection, dissemination, and transmissionItem Evaluating Genetic Diversity in Kenyan Pineapple (Ananas comosus) Germplasm Using Sequence-Related Amplified Polymorphism (SRAP) Markers(American Journal of Plant Science, 2025-04) Mwaniki, Lilian Mwende; Wanjala, Bramwel Waswa; Runo, Steven; Omwenga, George; Simiyu, Elphas SambuPineapple (Ananas comosus), a widely cultivated tropical fruit, is known for its global economic and nutritional significance. The study aimed to investigate the genetic diversity of 80 pineapple accessions from Kenya using Sequence-Related Amplified Polymorphism (SRAP) markers. Out of the 48 SRAP primers, six polymorphic primers were identified. Genetic diversity was examined using DARWin, GenAlEx, and PopGene software. DNA (deoxyribonucleic acid) extraction followed a modified CTAB (Cetyltrimethylammonium bromide) method, ensuring quality DNA for analysis. Polymerase Chain Reaction (PCR) was conducted with selected primers to amplify DNA segments, revealing polymorphisms. The findings revealed significant genetic differences among (22%) and within (78%) populations, with a PhiPT value of 0.221, Nei’s gene diversity (H) of 0.1761, and Shannon’s Information index (I) of 0.2699, indicating moderate population differentiation. Principal Coordinates Analysis (PCoA) explained 53.47% of the overall genetic variation, revealing a relatively homogenous genetic composition within accessions. Gene flow (Nm) was 1.3623, suggesting moderate gene flow among populations. The dendrogram grouped samples into two clusters, corroborating the homogenous genetic composition. No differentiation among populations was observed using Nei’s genetic distance matrix. The overall genetic similarity suggests that most populations share a common genetic background. Improving the genetic diversity of Kenyan pineapples is essential for enhancing resilience and sustainability. This can be achieved through collecting local ties, cross-breeding, importing new cultivars, conducting genomic studies, and establishing gene banks. These efforts will help make Kenyan pineapples more adaptable, productive, and resistant to climate change and other challenges.Item PlantGENE Report on Panel Discussion: Advancing Plant Biotechnology in Africa(Springer, 2025) Malzahn Aimee A.; Songstad Nicole; Tripathi Leena; Ihuoma Okwuonu; Sithole‑Niang Idah; Runo Steven; Wagaba Henry; Kouassi Modeste; Kaeppler Heidi; Gordon‑Kamm William; Keunsub Lee; Wayne Parrott; Nigel Taylor; Rogers Christian; Gafney Jim; Van Eck Joyce; Veena VeenaThis report provides an overview of the content and data collected from the “Successes, Challenges, and Opportunities Plant Transformation Research in Africa” panel discussion. Organized by PlantGENE, this event brought together scientists and stakeholders across the globe to examine the complex challenges and emerging opportunities in plant transformation research in laboratories across Africa. The discussion, rooted in insights from a panel of six leading scientists, highlights critical issues including restrictive regulatory environments, prohibitive costs, and the inconsistent availability of essential research materials. Additionally, the pervasive “brain drain” phenomenon, where skilled researchers leave the continent for better opportunities, exacerbates the difculties faced by African scientists. Despite these challenges, the report also identifes signifcant advancements, particularly in the growing recognition of African leadership within universities and national agricultural research systems (NARS). These institutions, supported by highly skilled faculty and motivated graduate students, are producing high-quality research that contributes to global scientifc knowledge. The panelists emphasized the necessity of creating an environment that encourages African scientists to remain on the continent and address local challenges through innovative research. Strengthening intra-African networks and fostering collaborations with the global scientifc community are proposed as essential strategies to achieve this. This report underscores the critical need for substantial investments from both global and African organizations, working with African governments, to support these eforts. Furthermore, it calls for science-based decision-making and fair regulatory frameworks to align with unique opportunities and risks associated with technological advancements in Africa. This paper details the observations of six panelists and analyzes the results of attendee surveys in order to document these challenges and opportunities while advocating for sustained investment and strategic partnerships to build a thriving bioeconomy across Africa.Item Evaluation of Formulated Strigolactone Analogs for Striga Management in Kenyan Agriculture(Elsevier B.V, 2025) Muhammad Jamil; Mutinda Sylvia; Jian You Wang; Barminga Damaris; Mwihaki Agnes; Navangi Lynet; Okiyo Teresa O.; Patil Rohit H.; Ngatia Titus; Mudavadi Patrick; Runo Steven; Al-Babili SalimStriga hermonthica, an obligate root parasitic weed affecting cereal crops, poses a significant threat to global food security in Sub-Saharan Africa (SSA). Germination of Striga seed largely relies on signaling molecules released by the host roots, mainly strigolactones (SLs). Suicidal germination is an effective strategy for reducing Striga seed banks in infested soils by applying SL analogs in the absence of a host. However, the challenge remains in developing suitably formulated SL analogs for field application. In this report, we assessed the activity of two SL analogs, MP3 and Nijmegen-1, in both granular and liquid formulations in laboratory and greenhouse settings, and conducted mini-field and field trials to evaluate their effectiveness under farmers’ conditions, using maize as the host crop in Kenyan agriculture. We observed a significant induction of Striga seed germination reaching up to 56 % in laboratory germination bioassays and a reduction in Striga emergence by up to 77 % in greenhouse pot studies. In mini- and field trials in different infested fields, we recorded up to 80 % and 65 % reduction in Striga emergence, respectively. In conclusion, the formulated SL analogs demonstrate significant potential to reduce Striga infestation in maize fields in Kenya and are promising candidates for use by farmers due to their simplicity, ease of handling, stability, and effectivenessItem Pathogen Dynamism and Variability of Rice Yellow Mottle Virus in Kenya(springer, 2025) Kigaru Antony; Nganga Everlyne M.; Murori Rosemary; Pappu Hanu R.; Runo Steven; Ateka Elijah M.Rice yellow mottle disease (RYMD) continues to constrain rice production in Africa. Rice yellow mottle virus (RYMV), which belongs to the Sobemovirus genus, is the causal agent of RYMD. In Kenya, previous studies on RYMV mostly focused on western Kenya, ignoring the central and coastal regions, which are also important areas for rice cultivation in the country. This has resulted in incomplete data on RYMD outbreaks. This study aimed to determine the prevalence of RYMD in the farmers’ felds, and the genetic diversity of the RYMV based on the coat protein gene. Field surveys were carried out in Kenya’s rice-growing regions between May and July 2023 to determine disease incidences using the IRRI Standard Evaluation Scale (SES) for rice. Symptom observations and serological tests confrmed the presence of RYMV in all surveyed rice cultivation areas. The presence of RYMV was detected in Kirinyaga, Tana River, and Taita Taveta counties of Kenya, representing the feld report of its occurrence in these regions. Disease incidence and severity analysis using one-way ANOVA showed no signifcant diference in RYMD incidence among the rice irrigation schemes (F (6,29)=1.838, P=0.1265). Sequencing results of the coat protein gene (ORF4 region) revealed that the RYMV isolates in this study could be classifed as S4ke, S4ug, and S4mg strains in the East Africa lineage. The discovery of the RYMV strain S4mg in Kenya runs counter to the gradual strain of breaking up and moving away that has been established in Africa over the past two centuries. Results showed that RYMV is present in all the rice-growing regions under study and exhibits intra-strain diversity in Kenya. Incorporating resistance genes into extensively grown rice cultivars is crucial for preventing the spread of the rice yellow mottle virus.Item Cholera in Sub-Saharan Africa: Unveiling Neglected Drivers and Pathways to Elimination(PLOS, 2025) Siamalube Beenzu; Ehinmitan Emmanuel; Runo Steven; Maina Ngotho; Onguso JustusCholera is a virulent infectious disease caused by the Gram-negative, comma-shaped bacteria Vibrio cholerae, after ingesting contaminated food and/or water. If left untreated, it can kill within 5 days. Since mid-2021 the world has recorded a notable increase in the seventh cholera pandemic, with high case fatality rate especially in Sub-Saharan Africa. Oral cholera vaccines are established but not readily available on the market, or if they are, they are not pocket friendly for low-resource-income countries. Hence, with the advent of green factory biotechnology, plant-derived edible vaccines are such a promising approach to supplement conventional vaccine methods. Human travellers are often the major transmitters as they move from region to region. Poor sanitation and inadequate clean water supply are services not readily available in most Sub-Saharan African countries, coupled with insufficient surveillance services, lack of early detection facilities, and the public not having ample awareness concerning sanitation and hygiene. This article highlights the epidemiology of cholera in Africa and expounds on what drives the outbreaks of cholera in this region. The discussion provides an in-depth analysis of the factors leading to the forsaken cholera drivers, emphasizing economic factors, culture, and environmental influences, particularly within the Sub-Saharan African communities. It presents a strategic blueprint approach that includes public health awareness, community participation, government involvement, and exploring emerging research tools. By merging these proposals into a unified context, a collective and practical methodology would be established to tackle the impact of cholera epidemiology that has been sidelined in Sub-Saharan AfricaItem Parasitic plants are models for examining global food security,biodiversity loss and host–parasite evolution, in achanging world(John Wiley & Sons, 2024) Runo Steven; Wicke Susann; Thorogood ChrisParasitic plants devastate crop productivity around the world, threatening food and nutritional security for millions. In this special issue of Plants People, Planet, we provide a systematic analysis of some of the most devastating parasitic plants that threaten global food security focusing on (i) witchweeds, (ii) broomrapes and (iii) vampireweeds. Witchweeds—members of the genus Striga—have earned themselves the nickname ‘cereal killers’ because of their devastating destruction of Africa's most staple cereals, including maize, sorghum, millets and upland rice. Striga is a highly successful parasite, the lifecycle of which is tightly synchronised with that of its host (Runo & Kuria, 2018). Central to this synchronisation is its ability to detect and locate would be hosts through biomolecules—predominantly strigolactones—emitted from the host (Al-Babili & Bouwmeester, 2014; Matusova et al., 2005). Ironically, the reliance of Striga on strigolactones (SLs) is also its Achilles' heel as this presents opportunities for control through manipulation of communication exchange. One approach involves growing Striga alongside a false host that releases SLs, which trigger Striga germination but fail to support its growth or infection (Khan et al., 2011). Another method uses germination stimulants applied to bare fields to induce Striga germination without a host (Jamil et al., 2022, 2024; Kountche et al., 2019). These methods are referred to as ‘suicidal germination’. Additionally, breeding host crops that produce insufficient or less potent SLs can also help manage Striga infestations. These strategies have made SLs a central focus of research for Striga control...Item In vivo antidiabetic and ex-vivo antioxidant activities of dichloromethane extract of Xerophyta spekei(springer, 2025) Ndile,Michael Musila; Makori, Wycliffe Arika; Kibiti,Cromwell Mwiti; Ngugi,Mathew PieroBackground The medicinal plant Xerophyta spekei is used among Embu and Mbeere communities to manage diabetes mellitus. However, its efficacy has never been evaluated in vivo. The purpose of this study was to investigate its quantitative phytochemical and antidiabetic potential. Extraction was done using Dichloromethane (DCM). Quantitative phytochemical analysis was conducted using GC-MS. To evaluate antidiabetic activity, groups of mice which included normal control, diabetic control, positive control, and extract-administered groups (50, 100, 150, and 200 mg/kg body weight) were used. Alloxan monohydrate was used to induce diabetes. Blood glucose of the mice was determined hourly for the first six hours, and once after 12 and 24 h on the first day. Thereafter, the blood glucose in mice was determined once a week for three weeks. During the experimental period of three weeks, body weights were determined. After 21 days, lipid profiles, kidney and liver function tests as well as ex vivo antioxidant assays were carried out. Results The phytochemicals classes identified included flavonoids, phenolic compounds, phytosterols, terpenoids, fatty acids, tocopherols and alkaloids. Stigmasterol had the highest concentration (12.99±2.56 mg/g). The extract decreased blood glucose dose-dependently, with 200 mg/kg bw dose resulting in the highest % mean change (40.10±0.95). The extract gradually decreased blood glucose during 21 days of treatment. It attenuated loss of body weight and aberrant biochemical parameters including liver and renal function tests as well as lipid profiles in diabetic mice. Furthermore, it reduced levels of malondialdehyde and enhanced enzymatic antioxidant activities in diabetic mice. Conclusions The study confirms that DCM extract X. spekei contains phytochemicals with antioxidant and antidiabetic properties. The findings authenticate the folkloric use of X. spekei in managing diabetes mellitus. The medicinal plant also serves as a potential source for developing antidiabetic agents.Item Simple and Fail-safe Method to Transform Miniprep Escherichia coli Strain K12 Plasmid DNA Into Viable Agrobacterium tumefaciens EHA105 Cells for Plant Genetic Transformation(bio-protocol, 2025) Siamalube,Beenzu; Ehinmitan,Emmanuel; Maina Ngotho; Onguso,Justus; Runo,StevenAgrobacterium-mediated gene transformation method is a vital molecular biology technique employed to develop transgenic plants. Plants are genetically engineered to develop disease-free varieties, knock out unsettling traits for crop improvement, or incorporate an antigenic protein to make the plant a green factory for edible vaccines. The method’s robustness was validated through successful transformations, demonstrating its effectiveness as a standard approach for researchers working in plant biotechnology. It enables the introduction of foreign DNA into plant genomes. Conventionally, plant genetic transformation has relied on time-consuming, costly, and technically demanding procedures, such as electroporation and chimeric viruses or biolistic methods, which usually yield variable transformation efficiencies. This study presents a simple and fail-safe protocol that involves a modified freeze-thaw and heat-shock concoction method. This approach involves a streamlined plasmid miniprep procedure to isolate high-quality plasmid DNA from Escherichia coli K12 strain, followed by a target-specific transfer into A. tumefaciens EHA105 strain. The optimized method minimizes DNA degradation and maximizes uptake by Agrobacterium cells, making it a reproducible and accessible protocol for various genetic engineering applications. The transformation efficiency is consistently high, enhancing plasmid uptake while maintaining cell viability, requiring minimal specialized equipment and reagents. The proposed protocol offers significant advantages, including simplicity, reliability, and cost-effectiveness, positioning it as a valuable alternative to traditional techniques in the field of plant biotechnology.Item Callosobruchus Maculatus: An Abiotic Enemy to Pigeon Pea Productivity(IJSRT, 2025) Katoo,Athanas Alexander; Ngugi,Mathew; Gitahi,StephenThe cowpea (pigeon pea) weevil, Callosobruchus maculatus, is a significant pest of stored pulses, particularly affecting crops like cowpea and pigeon pea in tropical and subtropical regions. This review examines the biology, life cycle, and the damaging effects of C. maculatus on stored pigeon pea grains. The insect undergoes a holometabolous life cycle, with rapid development influenced by temperature and humidity, which allows for multiple generations during a single storage season. The damage caused by C. maculatus includes direct feeding on seeds, resulting in weight loss, reduced seed viability, and compromised nutritional quality, along with contamination from insect frass and remains, further degrading the grains' marketability and safety. The economic impact is substantial, particularly in regions where pigeon peas are a staple crop, affecting food security and farmers' livelihoods. Control measures for C. maculatus include a combination of cultural, physical, chemical, and biological strategies. These include proper storage practices, the use of inert materials like diatomaceous earth, irradiation, low temperature treatments, and chemical controls, each with their advantages and limitations. Integrated pest management, utilizing multiple strategies, is essential for effective control and minimizing losses.Item Molecular Analysis of Human Respiratory Syncytial Virus Group B Strains Isolated in Kenya Before and During the Emergence of Pandemic Influenza A/H1N1(John Wiley & Sons, 2025-02) Wangui,Julia; Gachara, George; Mobegi,Victor; Agoti, Charles; Otieno,James; Opanda,Silvanos; Opot,Benjamin; Ngeranwa,Joseph N.; Njeru,Regina; Bulimo,WallaceBackground: We conducted a retrospective study to explore molecular insights into human respiratory syncytial virus (HRSV) group B strains among patients attending outpatient clinics at government medical facilities both prior and during the onset of Influenza A/H1N1/2009 pandemic outbreak. Methods: We screened 2300 nasopharyngeal swabs using multiplex real time reverse transcriptase polymerase chain reaction. We amplified a segment of the first and second hypervariable regions, as well as the conserved portion of the third domain of the G-gene using HRSV-B specific primers, sequenced by Sanger di-deoxy chain termination method and thereafter analyzed the sequences. Results: We characterized the circulating strains into three known genotypes: SAB4 (1.4%), BA7 (1.4%), and multiple variants of BA9 (97.2%). The majority of BA9 viruses were uniquely Kenyan with only 4% aligning with BA9 lineages found elsewhere. The mean evolutionary rate of the HRSV-B was estimated to be 3.08×10−3 substitutions per site per year. Conclusion: Our findings indicate that the circulating HRSV-B viruses in Kenya underwent a slower evolution during the pe riod of 2007–2010. Additionally, our findings reveal the existence of a unique lineage as well as new variants that have not been reported elsewhere to date.Item Evaluation of Growth and Yield of New Papaya (Carica Papaya L.) Hybrid Lines and Their Performance Against Moroccan Watermelon Mosaic Virus‐Causing Disease(John Wiley & Sons, 2024) Kosgei,Janet Chepng’etich; Asudi,George O.; Ombwara,Francis Kweya; Kariuki,Lilian W.; Rimberia,Fredah K.The production of Carica papaya L. in Kenya is seriously affected by the Moroccan watermelon mosaic virus and lack of improved varieties leading to the importation of expensive seeds for the resource‐scarce farmers. To curb these challenges, new papaya hybrid lines were recently selected and bred, but their growth traits and performance against papaya diseases were not evaluated. Therefore, we assessed the growth, development, and production characteristics of these new hybrid lines 1–8, with Sun rise Solo as control using the International Board of Plant Genetic Resources papaya descriptor in the field at the Jomo Kenyatta University of Agriculture and Technology, Juja. The hybrid trees matured 6–15 days before Sunrise Solo and fruited at heights of 23–37 cm lower than controls at the end of the harvesting stage, showing they could be harvested longer than the controls. Hybrid line 4 had larger fruits preferred for local markets and industrial use, while hybrid lines 1, 2, 5, 7, and 8 and Sunrise Solo had smaller and medium‐sized fruits suitable for exports. However, only hybrid lines 6 and 7 showed more tolerance to MWMV disease and powdery mildew. Therefore, normal agronomic practices are important for seed multiplication purposes to improve papaya production in Kenya.Item Transcriptome Atlas of Striga Germination: Implications for Managing an Intractable Parasitic Plant(ppp, 2023) Irafasha,Gilles; Mutinda, Sylvia; Mobegi,Fredrick; Hale,Brett; Omwenga,George; Wijeratne, Asela J.; Wicke,Susann; Bellis,Emily S.; Runo,StevenSocietal Impact StatementWitchweeds, parasitic plants of the genus Striga, are nicknamed “cereal killers”because of their devastating destruction of Africa's most staple cereals, includingmaize, sorghum, millets, and upland rice. The parasite relies on biomolecules emittedfrom the host roots to germinate and therefore initiate its infectious lifecycle. Somesorghum varieties have evolved to not produce effective germination stimulants,making them resistant to the parasite. Here, the genetic factors that underpin Strigagermination were assessed, followed by a discussion of how such knowledge can beused to develop new Striga management strategies through the disruption of host–parasite communication exchange.Summary• Seeds of the parasitic plant Striga are dormant. They only germinate in responseto biomolecules emitted from the host's root exudate, strigolactones (SL). But it isnow emerging that Striga germination is a much more complex process regulatedby crosstalk of hormone signaling pathways.• To further understand the genetic basis of the communication exchange betweenStriga and its host sorghum, we performed a comparative transcriptomic analysis.We sought to identify major transcriptomic changes that define the germinationprocess in Striga and a set of genes that may contribute to the differences in ger-mination rates.• Results showed that germination proceeds immediately after SL perception and ismarked by a wave of transcriptional reprogramming to allow for metabolic pro-cesses of energy mobilization. Cluster analysis using self-organizing maps revealeda time-phased and genotype-differentiated response to germination stimulation.The variation in germination was also a function of hormonal crosstalk. The earlygermination stage was associated with significant repre....Item Validity of Procalcitonin and C-Reactive Protein as Biomarkers in Diagnosis Ofneonatal Sepsis in a Referral Hospital, Kenya(Alexandria Journal of Medicine, 2024-11) Tum, Florence Chepyegon; Ngeranwa, Joseph J.N.; Maiyoh, Geoffrey K.; Frank G. OnyambuBackground: Neonatal sepsis (NS) is a significant health concern causing high morbidity and mortality among neonates. The clinical symptoms of NS can overlap with other common neonatal conditions. The gold standard diagnostic method, the blood culture test, has numerous limitations including lengthy turnaround time, which delays appropriate management of NS. Acute phase protein; procalcitonin (PCT) and C-reactive protein (CRP) tests have emerged as potential alternatives due to short turnaround times, high sensitivity, and specificity in detecting NS. Nevertheless, there is limited data on their usability in Kenyan public hospitals. This study, therefore, was conducted to validate the performance of PCT and CRP tests in diagnosis of NS locally. Methodology: Blood samples were collected from 196 neonates with suspected sepsis admitted at Moi Teaching and Referral Hospital (MTRH). Blood culture was performed using BacT/ALERT blood culture system. Bacteria growths were identified and antibiotic susceptibility for the isolates determined using Vitek II. Serum PCT levels were determined using the chemiluminescence immunoassay method. Serum CRP levels were measured using Immunoturbidimetry method. Results: Growth of organisms occurred in 45.4% of the sepsis suspected neonates. The sensitivity, specificity, positive predictive value, negative predictive value and area under the curve for PCT were 93.3%, 98.1%, 97.6%, 94.6% and 0.959, whereas for CRP they were 100%, 72.8%, 74.3%, 100%, and 0.953, respectively. Conclusion and Recommendation: The CRP test exhibited superior sensitivity, negative predictive value, but lower specificity, making it a more valuable tool for ruling out NS. Overall, however, PCT emerged as a more robust biomarker, offering a reliable balance between sensitivity and specificity, indicating its ability to identify cases with NS correctly. The area under the ROC curve confirms that CRP and PCT have high accuracy in detecting NS. The study recommends adoption of PCT and CRP biomarkers in the diagnostic protocols for NS.Item In Vitro Anti-Prostate Cancer Efficacy and Phytochemical Composition of the Dichloromethane and Ethyl Acetate Leaf Extracts Of Vitex Doniana (Sweet)(Frontiers in Pharmacology, 2024-11) Moriasi, Gervason; Ngugi, Mathew; Mwitari, PeterBackground: Prostate cancer is a significant global health concern, particularly among ageing male populations, with a disproportionately higher burden in subSaharan Africa. Conventional treatments, though effective, are costly and cause devastating side effects which limit their clinical benefits. Hence, this study evaluated the in vitro antiprostate cancer properties and secondary metabolites of dichloromethane and ethyl acetate lead extracts of Vitex doniana to explore safer and efficacious natural alternatives based on ethnomedicinal claims. Methods: Phytochemical profiling was conducted using gas chromatographymass spectrometry (GC-MS) analysis to identify secondary metabolites in the extracts. The cytotoxic effects of the extracts were determined through the MTT assay using Vero CCL-81 cells and DU-145 cells. The expression profile of the selected genes (ar, bcl2, caspase-3, cdk1, and p53) in DU-145 cells treated with the study extracts was investigated using RT-qPCR. Results: GC-MS analysis revealed 10 secondary metabolites in the dichloromethane extract and 27 secondary metabolites in the ethyl acetate extract of V. doniana leaves, with the majority being sesquiterpenes, diterpenoids, and phytosterols. The dichloromethane and ethyl acetate leaf extracts of V. doniana exhibited low cytotoxicity against normal mammalian epithelial cells (Vero CCL-81), with CC50 values of 1,238.85 μg/mL and 964.81 μg/ mL, respectively. Besides, the ethyl acetate leaf extract of the studied plant demonstrated potent anti-prostate cancer activity against DU-145 cells, with an IC50 of 35.68 μg/mL and a high selectivity index (SI) of 27.04. Likewise, the dichloromethane leaf extract of this plant displayed cytotoxic effects (IC50: 287.01 μg/mL) and a selectivity index of 4.32. The reference drug (Doxorubicin) showed a higher toxicity against Vero CCL-81(IC50: 0.41 μg/mL) and DU-145 (IC50: 0.28 μg/mL) cells and a lower selectivity index of 1.46. The DU145 cells treated with the studied plant extracts exhibited notable upregulation of ar and bcl2, and normalization of caspase 3, cdk1 and p53 expression. Conclusion: The studied plant extracts possess in vitro anti-prostate cancer properties and could be promising candidates for further preclinical studies aimed at developing novel botanical-based therapies for the management of prostate cancer.