School of Biosciences (Biosciences) Collectionshttp://hdl.handle.net/10570/1932024-03-29T15:46:48Z2024-03-29T15:46:48ZAflatoxin exposure in Southwestern Uganda and the ameliorative effects of selected medicinal plants on induced aflatoxicosis in wistar ratsMurokore, Biryomumaisho Justushttp://hdl.handle.net/10570/129702024-01-03T14:18:45Z2023-11-01T00:00:00ZAflatoxin exposure in Southwestern Uganda and the ameliorative effects of selected medicinal plants on induced aflatoxicosis in wistar rats
Murokore, Biryomumaisho Justus
Introduction: Over 5.5 billion people, worldwide are chronically exposed to aflatoxins. This contributes to 40% of the African disease burden. Aflatoxins are mycotoxins produced by Aspergillus flavus and A. parasiticus, A. nomius, and A. tamarii, which are fungal species. Aflatoxin B1 (AFB1) is the most prevalent and carcinogenic among them. Since prevention of their production is not practical, we ingest them making toxicity control the easiest option. Consumption of high phenolic medicinal plant ameliorates the toxicological effects of aflatoxins. Objectives: The goal of the study was to assess dietary aflatoxin exposure in selected foodstuffs in Southwestern Uganda and the ameliorative effects of selected medicinal plants on aflatoxicosis in wistar rats. Specifically, the study set out to: (i) determine the aflatoxin susceptible food consumption frequency, prevalence and levels of aflatoxins in household foodstuffs in Southwestern Uganda; (ii) determine the phenolic, and flavonoid contents and antioxidant capacity of different selected medicinal plants (iii) assess the ameliorative effects of the selected medicinal plants on aflatoxin induced changes in liver, kidney and immune functions. Methods: Flours of Arachis hypogaea (groundnuts), Zea mays (maize), Eleusine coracana (millet), and Sorghum bicolor (sorghum), the most commonly aflatoxin contaminated foods, were systematically sampled, following a consumption frequency questionnaire. Samples were analysed for aflatoxin content using competitive ELISA. Ocimum gratissimum, Allium sativum, Cymbopogon citratus, Zingiber officinale, and primary grades and green tea, Camellia sinensis, were analysed for phenolics and flavonoids, following Folin-ciocalteu and Aluminium chloride methods respectively. Their antioxidant capacity was determined following DPPH and FRAP methods. Ninety-six male wistar rats were grouped into 16 groups of 6 and treated for 30 days as follows; 1. Control, 2. Olive oil. 3. AFB1 Low-dose (100µg/kg), 10. AFB1 High-dose (300µg/kgAFB1). 4-9. AFB1 Low-dose + 2% extracts, 11-16. AFB1 High-dose + 2% extract. Liver and kidney functions, histopathology, and immune function indicators were evaluated using standard methods. Results: The highest aflatoxin prevalence, levels and consumption frequency were observed in maize and groundnuts (Tables 4.1.2 and 4.1.1, respectively). Indoor dried/processed medicinal plants yielded higher total phenolic content (TPC) than fresh ones. In addition, 40 minutes extracts of medicinal plants yielded higher TPC. Green tea yielded the highest DPPH (93.82%) and FRAP (39.04µg AAE/mL), and tea harvested from Buganda (4,371 µgQE/g) the highest total flavonoid content (TFC). Green and black tea, C. sinensis, O. gratissimum, and C. citratus reduced the damaging effects of aflatoxin toxicity in liver functions, histopathology and blood and immunity parameters. Conclusion: Groundnut and maize were the main foods through which aflatoxin exposure occurs. For maximum TPC, it is better to use processed medicinal plants and longer extraction periods. Green and black tea, C. sinensis, O. gratissimum, and C. citratus have ameliorative effects in aflatoxicosis. Community awareness in aflatoxin contamination avenues and health effects, and encouragement to regularly consume high phenolic medicinal plants is urgently needed.
A thesis submitted to the Directorate of Research and Graduate Training in fulfilment of the requirements for the award of a Doctor of Philosophy of Makerere University, Kampala- Uganda
2023-11-01T00:00:00ZAmphibian diversity patterns in the Namulonge agricultural landscapeAkoth, Sisiriahttp://hdl.handle.net/10570/62042018-05-29T23:12:38Z2017-01-01T00:00:00ZAmphibian diversity patterns in the Namulonge agricultural landscape
Akoth, Sisiria
Uganda’s agricultural landscapes are patterns of cultivated areas and semi-natural elements. Although comprising only a small fraction of the total area, semi-natural elements provide habitats for most of the landscape biodiversity. Agricultural intensification has increasingly destroyed or fragmented semi-natural elements resulting into species decline. Insights into the effects of landscape structure on species’ distributions within and among semi-natural habitats are needed to effectively conserve biodiversity in agricultural landscapes. The influence of land use practices on amphibian species diversity was investigated in areas of intensive and subsistence agriculture in Namulonge for 12 weeks. Amphibians were sampled using Visual Encounter Surveys while environmental parameters were measured using digital multimetre. Altogether, 19 amphibian species were recorded in the Namulonge agricultural landscape. The Mann-Whitney U test showed no significant difference in species diversity between the land use areas. Characteristics of the landscape were used to predict patterns of amphibian species distribution in canonical correspondence analysis (CCA). The model identified plant materials, water and ambient temperature as the most important variables in predicting species distribution. Areas with relatively intact natural vegetation cover supported a few more species than completely converted areas. Such pockets of vegetation provide microhabitat conditions suitable for amphibian species occurrence. The foregoing observation suggests that there is value at landscape-level to preserve natural/semi-natural pockets of vegetation to enhance biodiversity in any agricultural environment.
A thesis submitted in partial fulfillment of the requirements for the award of the Masters of Science Degree in Zoology of Makerere University
2017-01-01T00:00:00ZAnalgesic, anti-inflammatory and oxytocic activities of Dracaena steudneri Engl. stem bark aqueous extract in Wistar ratsKatuura, EstherTenywa, Mercy GladysAgaba, Amon GanafaAjayi, Clement OlusojiTolo, Casim Umbahttp://hdl.handle.net/10570/106862022-07-19T10:08:05Z2022-01-01T00:00:00ZAnalgesic, anti-inflammatory and oxytocic activities of Dracaena steudneri Engl. stem bark aqueous extract in Wistar rats
Katuura, Esther; Tenywa, Mercy Gladys; Agaba, Amon Ganafa; Ajayi, Clement Olusoji; Tolo, Casim Umba
Dracaena steudneri Engl. (Dracaenaceae) is a medicinal plant that is used in labour by traditional birth attendants to induce labour, relieve pain and treat various diseases; albeit no documentation. This study determined the analgesic, anti-inflammatory and oxytocic effects of the D. steudneri stem bark aqueous extract. D. steudneri stem bark was collected, authenticated, oven-dried at 45ºC for 48 h, pulverized and extracted using the decoction method. The analgesic effect of the aqueous extract was determined using the acetic acid writhing test, anti-inflammatory activity was determined using paw oedema method while oxytocic activity was determined using abortion and other standard test procedures and were tested at 12.1 24.1 and 48.2 mg/kg. The results of the analgesic study showed that the extract reduced the number of abdominal writhing between 53.51 and 92.40% at 6.02 and 48.2 mg/kg dose, respectively while the standard drug showed a reduction of 36.58% at 10 mg/kg. The anti-inflammatory results showed percentage inhibition of 18.6% (2 h), 22% (2 h) and 18.9% (6 h) at 12.1, 24.1 and 48.2 mg/kg, respectively. The in vivo oxytocic activity showed average time taken for the rats to deliver was between 20.63 h at lowest dose (12.1 mg/kg) and 8.25 h at highest dose (48.0 mg/kg) while Oxytocin the reference drug exhibited, 22 h as the average time taken for delivery.
Journal article
2022-01-01T00:00:00ZAnalysis of microbial quality of common bean (Phaseolus vulgaris l.) seeds from five bean producing districts in UgandaIsout, Sylashttp://hdl.handle.net/10570/102072022-04-26T08:41:48Z2022-04-25T00:00:00ZAnalysis of microbial quality of common bean (Phaseolus vulgaris l.) seeds from five bean producing districts in Uganda
Isout, Sylas
Being a basic and an affordable source of protein, common bean (Phaseolus vulgaris L.) is grown widely in Uganda and the world at large. The quality of bean seeds has gained little attention yet remains a significant aspect of the value chain of production and consumption in Uganda. The aim of this study was to assess the microbial quality of common beans from five bean producing districts of Uganda. One hundred bean samples were collected from farmers and traders purposively selected from five bean producing districts of Uganda (Arua, Oyam, Hoima, Nakaseke, and Sironko districts). Three replicates of twenty samples of bean seeds randomly obtained from each district were subjected to microbial quality analysis using whole seed and agar plate standard protocols under laboratory conditions. The modified blotter method was used to test germinability and health of bean seeds in the laboratory. Standard seedling symptom tests were conducted in screen house experiments using a completely randomized design to assess germination and health of bean seedlings. Seed health tests revealed that 85% of the bean samples were contaminated with seed borne fungi. Five seed borne fungal genera were isolated from the seed samples, with Aspergillus (42.8 %) and Fusarium (37.1 %) being the most common fungi followed by Penicillium (18.9 %) while Colletotrichum (12.2 %) and Rhizopus (6.2%) were the least occurring fungi. Xanthomonas sp. was the only bacteria isolated from 15% of the samples tested. In the laboratory, bean seeds exhibited relatively poor germination (58.2%), with 30.9% of seeds having fungal outgrowths. While in the screen house, only 63.2% of seeds germinated, with 23.9% of ungerminated seeds being rotten. Disease assessment in the screen house revealed that, 25.1% of seedlings were diseased with various symptoms. Six seed borne diseases were recorded including; Fusarium wilt, Angular leaf spot (ALS), Ascochyta blight, Anthracnose, Common Bacterial Blight (CBB) and Bean common mosaic virus (BCMV). Determinately, the beans available in Uganda are of low/poor quality. Poor quality seeds contaminated with seed borne pathogens may result in poor germination rates, poor health of seedlings and reduced crop stand and yield. Therefore, improving access to clean and healthy seed for farmers is inevitable. Farmers are urged to embrace good bean production practices especially disease management in the field and post-harvest handling practices in order to improve production of safe and quality beans.
A dissertation submitted to the Directorate of Research and Graduate Training in partial fulfilment of the requirements for the award of the Degree of Master of Science in Botany of Makerere University
2022-04-25T00:00:00Z