School of Agricultural and Food Scienceshttp://ir.jooust.ac.ke/handle/123456789/352024-03-29T04:53:05Z2024-03-29T04:53:05ZThe Nutritional Composition and Sensory Properties of Wheat Muffins Enriched with Gonimbrasia zambesina Caterpillar FlourOpondo, FedinandNakhumicha, AliceAnyango, Josephhttp://ir.jooust.ac.ke/handle/123456789/109172022-05-21T08:58:36Z2022-04-01T00:00:00ZThe Nutritional Composition and Sensory Properties of Wheat Muffins Enriched with Gonimbrasia zambesina Caterpillar Flour
Opondo, Fedinand; Nakhumicha, Alice; Anyango, Joseph
Protein malnutrition is a serious challenge in the developing countries. Attention is shifting to the use of edible insects in a form which is acceptable to people irrespective of social status and level of civilization in efforts to alleviate protein malnutrition. Gonimbrasia zambesina caterpillar emerge seasonally in the coastal part of Kenya. Despite their rich protein, fat and mineral contents, their consumption is low. This study was thus undertaken to evaluate the effect of substituting wheat flour with 0%, 5%, 10%, 15% and 20% of G. zambesina caterpillar flour on the nutritional composition and sensory properties of wheat muffins. The substitution levels were in accordance with the recommendations by Kenyan Bureau of Standards (KEBS). Substitution of wheat flour with G. zambesina caterpillar flour resulted into significantly high crude protein, crude fat and crude fibre content. There was an increasing trend in the ash, minerals and tocopherol content with increase in substitution level of wheat flour with G. zambesina caterpillar flour. The Invitro protein digestibility (IVPD) significantly decreased from 10%-20% substitution levels of wheat flour with G. zambesina caterpillar flour. There was a significant difference (p<0.05) in the carbohydrate contents of enriched wheat muffins. The sensory score for colour, texture, aroma and overall acceptability of the wheat muffins also decreased with increasing substitution level of G. zambesina flour. At 10% substitution level of wheat flour with G. zambesina caterpillar flour, wheat muffins had significantly higher nutritional content than control wheat muffins (0%) and was comparable to muffin enriched with 5% G. zambesina caterpillar flour in terms of overall acceptability. Thus, enriching wheat muffins with G. zambesina caterpillar flour at 10% substitution level has the potential to improve the nutritional health of people suffering from protein malnutrition since they are richer in protein with a digestibility of over 88.8% and are acceptable.
2022-04-01T00:00:00ZProceedings of the second horticulture seminar on sustainable horticultural production in the tropicsWesonga, J.MLosenge, T.Ndung’u, C.K.Ngamau, K.Njoroge, J.B.M.Ombwara, F.K.Agong', Stephen G.Frickea, A.Hau, B.Stützel, H.http://ir.jooust.ac.ke/handle/123456789/25512018-11-08T08:57:08Z2002-08-01T00:00:00ZProceedings of the second horticulture seminar on sustainable horticultural production in the tropics
Wesonga, J.M; Losenge, T.; Ndung’u, C.K.; Ngamau, K.; Njoroge, J.B.M.; Ombwara, F.K.; Agong', Stephen G.; Frickea, A.; Hau, B.; Stützel, H.
Participatory Rural Appraisal (PRA) method was used to identify seventeen Musa cultivars that were rated highly by the small-scale farmers in Kenya. The cultivars were studied alongside five reference cultivars of genomic groups AA, AB, AAA, AAB, and ABB. This investigation was done to uncover the genomic groups prevalent among the Kenyan cultivars, as well as sort out synonyms to enable in vitro production of true-to-type plants. Random Amplified Polymorphic DNA (RAPD) markers with ten 10-mer primers was used for molecular characterization. The primers generated sixty-nine genetic markers that were used in estimation of genomic groups and cultivar identification. Pairwise RAP Distance analysis of the data and subsequent generation of a genogram using the ‘Neighbor Joining Tree’ programme grouped the cultivars into two major clusters depending on their genomic similarities. One cluster comprised of the Kenya-highland bananas, which grouped with the AAA reference cultivar ‘Poyo’. The other cluster contained the coastal lowland cultivars, which grouped with the ABB, AAB, and AB reference cultivars ‘Saba’, `Kelong Mekindu`, and `Safet Velchi’ respectively. The dissimilarity analysis between the samples did not indicate duplication among the banana accessions. Each cultivar was genotypically different although some were closely related.
2002-08-01T00:00:00ZIron concentrations in roots and edible organs of African indigenous vegetable speciesEckhardt, UlrichBeer, JuliusBessler, HolgerNambafu, Godfrey N.Onyuka, EnosAndika, Darius O.Gweyi-Onyango, Joseph PatrickEngels, Christofhttp://ir.jooust.ac.ke/handle/123456789/12052018-01-31T08:33:27Z2015-09-01T00:00:00ZIron concentrations in roots and edible organs of African indigenous vegetable species
Eckhardt, Ulrich; Beer, Julius; Bessler, Holger; Nambafu, Godfrey N.; Onyuka, Enos; Andika, Darius O.; Gweyi-Onyango, Joseph Patrick; Engels, Christof
Iron (Fe) deficiency is among the 10 leading human health risks causing “hidden hunger” in sub- Saharan Africa. Iron concentrations and bioavailability are often higher in leafy vegetables than in staple crops like maize and sorghum. Therefore, increasing food diversity through vegetable production and consumption is an option to mitigate Fe deficiency. The aim was to quantify Fe uptake and distribution between roots, stems and leaves in selected African indigenous vegetable (AIV) species, and to compare species responses to different rates of Fe supply. Plants of five leafy AIV species (African night shade Solanum scabrum, amaranth Amaranthus cruentus, cowpea Vigna unguiculata, spider plant Cleome gynandra, Ethiopian kale Brassica carinata) and a standard species commonly grown in Kenya (kale Brassica oleracea acephala group) were grown in nutrient solution at three rates of Fe supply (sub-optimal to induce Fe deficiency responses, optimal for growth, supra-optimal to test if Fe density in edible organs can be enhanced by additional Fe fertiliser application). Leaf chlorophyll content (SPAD-meter) and pH of the nutrient solution were measured at regular intervals to quantify shoot and root responses to Fe deficiency. At harvest, biomass and mineral nutrient concentrations were measured separately for roots, stems and leaves. The species markedly differed in their early root responses to Fe deficiency. Whereas in amaranth, proton extrusion from roots was significantly increased at low Fe supply compared to medium and high Fe supply, in spider plant and kale proton extrusion was not influenced by Fe supply. Fe concentrations in the plant dry mass strongly varied among plant organs and decreased in the order roots >> leaves > stems. In all organs, Fe concentrations were significantly affected by species. Concentrations in shoots varied from 17 (Ethiopian kale) to 39 mg Fe kg−1 dry mass (amaranth) at low Fe supply, and from 42 (Ethiopian kale) to 127 mg Fe kg−1 dry mass (cowpea) at high supply respectively Responses of Fe density in edible plant organs indicate that the potential for increasing the nutritional value of leafy vegetables by Fe fertilisation (biofortification) is largest in cowpea and spider plant.
2015-09-01T00:00:00ZCadmium uptake and distribution to edible organs in African indigenous vegetablesOnyuka, EnosHusen, Wilhelm vanNambafu, Godfrey N.Bessler, HolgerAndika, Darius O.Gweyi-Onyango, Joseph PatrickMwonga, SamuelUlrichs, ChristianEngels, Christofhttp://ir.jooust.ac.ke/handle/123456789/12042018-01-31T08:11:44Z2015-09-01T00:00:00ZCadmium uptake and distribution to edible organs in African indigenous vegetables
Onyuka, Enos; Husen, Wilhelm van; Nambafu, Godfrey N.; Bessler, Holger; Andika, Darius O.; Gweyi-Onyango, Joseph Patrick; Mwonga, Samuel; Ulrichs, Christian; Engels, Christof
Cadmium (Cd) is toxic to humans. The most important source for dietary intake is consumption of plant products, whereby Cd concentrations in leafy vegetables are particularly high. In peri-urban areas, soils are often contaminated with Cd. Thus, recommendations to increase vegetable consumption should consider species-specific uptake and allocation to edible plant organs. Cadmium uptake and distribution within plant was compared in various species to derive recommendations for vegetable production on contaminated soils. Four African indigenous vegetable species (African Nightshade Solanum scabrum, amaranth Amaranthus cruentus, cowpea Vigna unguiculata, spider plant Cleome gynandra), and a standard species commonly grown in Asia (Pak Choi Brassica rapa chinensis) were grown in nutrient solution at three Cd-concentrations: 0.1 (low), 1.0 (moderate)
and 2.5μ M Cd (high contamination). Biomass and mineral nutrient concentrations were measured in roots, leaves, stems and lateral branches. Growth was little affected by Cd supply with the exception of amaranth and cowpea. In these species, growth of shoot organs was substantially reduced at moderate and high supply. Growth depression was associated with low leaf iron concentrations indicating Cd-induced iron deficiency. In all species Cd concentrations were higher in roots than in shoot organs, which is in accordance with xylem loading being an important barrier for Cd distribution within plants. At moderate and high supply, Cd concentrations in shoot organs strongly differed among species. Concentrations were particularly low in cowpea, and high in amaranth and African Nightshade. Low Cd concentrations
in shoot organs of cowpea were associated with low apparent uptake and translocation rates of Cd from roots to shoots. At all rates of Cd supply, Cd density in edible organs was significantly influenced by species. Cadmium density was particularly low in cowpea and Pak Choi. Based on a vegetable dish of 250 g fresh mass, best choice of species reduced Cd intake by 0.1 mg at low supply (amaranth versus African Nightshade), 0.7 mg at moderate (cowpea versus African Nightshade) and 1.7 mg at high Cd supply (cowpea versus amaranth). Best choice of vegetable species can considerably reduce Cd intake by humans.
2015-09-01T00:00:00ZStrategies of African indigenous vegetables to cope with phosphorus deficient soilsNambafu, GodfreyOnyuka, EnosBessler, HolgerHoeppner, NicolaiAndika, Darius O.Gweyi-Onyango, Joseph PatrickMwonga, SamuelEngels, Christofhttp://ir.jooust.ac.ke/handle/123456789/12032018-01-31T06:56:48Z2016-09-01T00:00:00ZStrategies of African indigenous vegetables to cope with phosphorus deficient soils
Nambafu, Godfrey; Onyuka, Enos; Bessler, Holger; Hoeppner, Nicolai; Andika, Darius O.; Gweyi-Onyango, Joseph Patrick; Mwonga, Samuel; Engels, Christof
Food production in smallholder farming systems of sub-Saharan Africa is often constrained by low soil contents of plant-available phosphorus (P). An option to increase food production is cultivation of species with high P efficiency. Plant strategies to improve growth and P acquisition on low P soils include root foraging strategies to improve spatial soil exploitation, P mining strategies to enhance desorption, solubilisation or mineralisation, and improving internal P utilisation efficiency.
The aim of this study was to measure plant responses to low P availability in soil and to determine if there is variation among African indigenous vegetables (AIV) in their ability to use organic phosphate and sparingly soluble P forms.
Six AIV species (Spider plant Cleome gynandra, African nightshade Solanum scabrum, Amaranthus Amaranthus cruentus, Cowpea Vigna unguiculata, African kale Brassica carinata, Common kale Brassica oleracea) were cultivated under controlled conditions in pots on a low P substrate. The substrate was amended with P using four different forms (highly soluble K2HPO4, sparingly soluble FePO4 or phosphate rock, phytate). Measurements included biomass and P concentration in shoots and roots, morphological root traits (root length and diameter, root hair density) and substrate characteristics (pH, content of soluble P) after harvest.
The AIV species significantly differed in morphological root traits and rhizosphere pH, and in the responses of morphological root traits to different P treatments. For example in average of all P levels rhizosphere pH varied from 3.9 in Amaranthus to 6.0 in African kale. All species were able to use P from phytate as effectively for biomass formation as P from K2HPO4. The efficiency for utilisation of sparingly soluble P forms (either FePO4 or rock phosphate) was low in African nightshade and Spider plant, and high in Amaranthus and African kale. Cowpea was efficient in utilisation of P from rock phosphate but not from FePO4.
The data indicate large variation among AIV species in root traits relevant for P acquisition and their ability to use soil P from different sparingly soluble P forms. This information may be used for site-specific recommendation of species best adapted to low P soils.
2016-09-01T00:00:00ZEssential and toxic minerals in leafy vegetables from open air and supermarkets in NairobiNambafu, Godfrey N.Adam, AnnaOnyuka, EnosMwonga, SamuelAndika, Darius O.Gweyi-Onyango, Joseph PatrickEngels, Christofhttp://ir.jooust.ac.ke/handle/123456789/12022018-01-31T06:00:18Z2015-09-01T00:00:00ZEssential and toxic minerals in leafy vegetables from open air and supermarkets in Nairobi
Nambafu, Godfrey N.; Adam, Anna; Onyuka, Enos; Mwonga, Samuel; Andika, Darius O.; Gweyi-Onyango, Joseph Patrick; Engels, Christof
Deficiency of macroelements such as calcium (Ca) and microelements like zinc (Zn) is widespread in sub-Saharan Africa, particularly among the poor, for which diets are strongly based on staple crops like maize and sorghum. Increasing diet diversity through African indigenous vegetables (AIV) might be an option to reduce hidden hunger caused by mineral deficiency. In addition to mineral deficiency, toxicity of heavy metals like cadmium (Cd) and lead (Pb) is another important health risk which is closely related to dietary intake of plant products. Vegetables may be contaminated by toxic elements through superficially adhering dust on edible surfaces or root uptake from soil and internal distribution to edible organs.
In this study, essential and toxic elements were measured in edible plant organs of vegetables sold on markets in Nairobi to assess potential health benefits and risks associated with consumption of AIV.
Fresh samples from AIV (Solanum scabrum, Amaranthus cruentus, Vigna unguiculata, Cleome gynandra, Brassica carinata) and a standard species commonly grown in Kenya (Brassica oleracea acephala group) were collected from ten open air and five supermarkets in Nairobi. Before mineral analysis, the edible parts of the vegetables were washed either with distilled water to remove minerals associated with externally adhering soil and dust, or 1% nitric acid to remove minerals associated with epidermal cell walls, or not washed at all. Essential (e.g., Ca, magnesium Mg, iron Fe, Zn) and toxic (e.g., Cd, Pb) mineral elements were measured.
The results showed that mineral element concentrations were similar in samples from open air and supermarkets, with the exception of Pb concentrations which were markedly higher in open air markets, indicating contamination by traffic. In 10% of all samples Cd concentrations exceeded 1 mg kg-1 dry mass indicating that vegetables may be an important source for dietary intake. Iron concentrations were very high. Washing with water or nitric acid strongly reduced Fe and Al concentrations, indicating that high Fe concentrations were mainly due to external contamination. Concentrations of Zn and Mg were very high in amaranth suggesting that this species is a particularly valuable source of these essential elements.
2015-09-01T00:00:00ZLinking farmers to markets through modern Information and Communication Technologies in Kenya.Mukhebi, A.WKundu, J.Okolla, A.Wambua, M.Ochieng, W.Fwamba, G.http://ir.jooust.ac.ke/handle/123456789/11952018-01-18T06:31:22Z2007-01-01T00:00:00ZLinking farmers to markets through modern Information and Communication Technologies in Kenya.
Mukhebi, A.W; Kundu, J.; Okolla, A.; Wambua, M.; Ochieng, W.; Fwamba, G.
This paper highlights a market information and linkage system (MILS) developed and tested by the Kenya Agricultural Commodity Exchange Limited (KACE) that increases the efficiency of agricultural markets to work better for smallholder farmers and other small and medium sized agro-enterprises (SMEs). The MILS involves harnessing modern information and communication technologies (ICTs) to empower farmers with low-cost reliable and timely market information to enhance the bargaining power of the farmer for a better price in the market place, and to link the farmer to markets more efficiently and profitably. The components of the KACE MILS are(www.kacekenya.com): Rural based Market Information Points (MIPs) which are information kiosks located in rural markets, District-level Market Information Centres (MICs), Mobile Phone Short Messaging Service (SMS), Interactive Voice Response (IVR), Internet based database system, rural FM radio and the Central Coordinating Hub in Nairobi. KACE has adopted a business approach to the provision of its services: users pay for the services. For instance, it charges: placement fees per initial offer or bid (US$ 1.5-15), commissions on concluded deals (0.5%-5%), subscriptions to price information recipients (US$ 65 for 6 months or US$ 125 for 12 months), fees to visiting foreign groups (US$ 2,000-5,000/visit) and revenue sharing agreements with SMS and IVR service providers. When the KACE MILS services are scaled out and widely used by many farmers and SMEs across Kenya, the system will generate sufficient revenue to sustain its services without reliance on development partner funding. To enhance the financial sustainability of the MILS services further, KACE has recently initiated two innovations: franchising MIPs and MICs to local entrepreneurs, and establishing a virtual trading floor to improve the matching of offers and bids through a rural-based FM Radio program. A recent study of the impact of the KACE MILS concluded that the proportion of farmers and traders that say their incomes has increased and their bargaining positions have improved is very high (75% farmers and 60% commodity traders). Furthermore, the study concluded that it was clear that during the years in which the KACE MILS has been operational, market integration improved for two commodities studied (i.e. maize and beans). This study also highlights the challenges faced by the KACE MILS, including poor infrastructure that imposes high transport costs to markets, high costs of mobile phone calls and SMS and small quantities of produce of varying quality offered. Keywords: Information and communication technology, innovations, Kenya.
2007-01-01T00:00:00ZA culture dependant biodiversity study of extreme haloalkaliphilic bacteria from Magadi soda Lake KenyaNyakeri, Evans M.Ogola, Henry J.Boga, Hamadihttp://ir.jooust.ac.ke/handle/123456789/1732016-11-16T05:38:53Z2015-06-24T00:00:00ZA culture dependant biodiversity study of extreme haloalkaliphilic bacteria from Magadi soda Lake Kenya
Nyakeri, Evans M.; Ogola, Henry J.; Boga, Hamadi
The present study that aimed at studying the microbial ecology of Lake Magadi, isolated 37 isolates from Lake Magadi using mineral and carbon rich media types. They were characterized bycultural, biochemical and molecular approaches and screened for the ability to produce useful biotechnological enzymes and biomolecules. Screening was done by plating on basal media supplemented with the respective substrate. 34 of the isolates were Gram positive, one was Gram negative and two were Gram variable. Most of the isolates grew well at pH ranging from 6.0 – 11.0, (optimum 9.0-10.0), temperature range of 20-45oC (optimum of 30-35oC) and salinity range of 5- 30 %, optimum growth was noted at 10-15% salinity, showing that they are true haloalkalophiles. 15 isolates produced various extracellular enzymes such as amylases, lipases and proteases. Partial sequence blast analysis showed that the bacteria belonged to genera Bacillus, Clostridium and Halomonas, with relative abundances of 54%, 38% and 8% respectively. The similarity values of some of the isolates to their closest neighbours (78% 80%, 84%, 85%, 88% and 94-97%) show that they may represent new species or novel genera respectively within the lake ecosystem. The study results show that Lake Magadi harbours ecologically important micro-organisms which also have the potential for application in the biotechnology industry.
1st JOOUST Scientific Conference
2015-06-24T00:00:00ZFactors influencing sorghum production by smallholder farmers in Waia division, Makueni County, KenyaMutua, Nahshon N.Ouma, George O.Odadi, Wilfred. O.http://ir.jooust.ac.ke/handle/123456789/1722016-11-16T05:26:57Z2015-06-24T00:00:00ZFactors influencing sorghum production by smallholder farmers in Waia division, Makueni County, Kenya
Mutua, Nahshon N.; Ouma, George O.; Odadi, Wilfred. O.
Smallholder farmers in arid and semi-arid lands in Kenya are frequently affected by drought and famine which lead to starvation and malnutrition especially of children, women, the aged and disabled. Maize being the most preferred stable crop has low yields and of low quality due to drought. This has led to abject poverty among smallholder farmers. Therefore food security measures are urgently needed especially the choice of crop to salvage the situation lest smallholder farmers in these regions suffer serious food shortage. This study was carried out in Waia Division, Mbooni East District, Makueni County. The specific objectives of the study were; to find out the influence of socio-economic factors on sorghum production, to investigate the government policy influence on sorghum and to determine the influence of climatic factors on sorghum production. Descriptive research design was used in this study while descriptive survey method was used to collect data using questionnaires which were administered to smallholder farmers. Data collection was done on April/May 2013 in the four sub-locations of Waia division. A sample of three hundred and forty four smallholder farmers were selected using stratified proportionate random sampling and were interviewed. Descriptive statistics namely frequencies, percentages, cumulative percentages were used to analyze the data using Statistical Package for the Social Sciences (SPSS) software version 16. Null Hypothesis; socioeconomic factors do not influence sorghum production was tested using the chi-square method. The study observed that socio-economic factors (age, gender, land size, level of education, level of income, methods of sorghum production and land system) significantly influenced sorghum production. Climate change and government policy significantly influenced sorghum production. The study concluded that there is a great potential of sorghum production in Makueni. The study recommended that the smallholder farmers needed support from financial advisory services, sorghum production extension services and marketing by government, non- governmental organizations and private investors.
1st JOOUST Scientific Conference
2015-06-24T00:00:00ZCommunity based-sorghum seed multiplication as a strategy for enhancing sorghum production for improved smallholder incomes and livelihoods in Siaya CountyAkuno, W.Akhaukwa, Patrick J.Osika, N O.Muchelle, F.http://ir.jooust.ac.ke/handle/123456789/1702016-11-15T13:01:05Z2015-06-24T00:00:00ZCommunity based-sorghum seed multiplication as a strategy for enhancing sorghum production for improved smallholder incomes and livelihoods in Siaya County
Akuno, W.; Akhaukwa, Patrick J.; Osika, N O.; Muchelle, F.
A significant proportion of the Kenyan population experiences food insecurity and malnutrition. The most affected are children and expectant mothers who depend on maize meal for food. Maize is a staple food in Kenya with over 90% of the population depending on the crop both for food and cash. However, with the unpredictable global climate change coupled with outbreaks of maize lethal necrosis disease in the high potential maize zones, sorghum is one of the best options for food security. The production of sorghum is hampered by the unavailability of seeds suitable for appropriate agro-ecological and socio-economic needs of small-scale farmers. The farmers are faced by a scenario whereby seed companies supply only hybrid varieties which cannot be recycled meaning farmers have to purchase fresh seeds every planting season. Over the last two years there has been a deliberate effort by farmer groups, courtesy of the KAPAP project, to bulk an Open Pollinated Variety (OPV) known as Mercia in Siaya County, a variety that is now available to farmers for replanting. The community seed bulking and farmer-farmer sharing of seed has not only increased the number of farmers involved in sorghum production but has enhanced the availability of sorghum seed to other farmers who could hitherto not afford good seed. The objectives of the study were to identify sorghum common interest groups to promote growing of high yielding variety of sorghum and to avail high yielding variety and evaluate its acceptability. It involved a baseline survey to identify the groups, training on sorghum production, growing of the high yielding seed by the farmer groups and evaluation of its acceptability by the farmers. The study revealed that smallscale farmers continue to experience lack of good seed variety to plant and that this project not only brought in a viable seed variety but also sensitized them on other uses of sorghum.
1st JOOUST Scientific Conference
2015-06-24T00:00:00Z