Food Safety(Aflatoxin-Studies)

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Determination of Optimum Conditions for Enzymatic Debranching of Cassava Starch and Synthesis of Resistant Starch Type III using Central Composite Rotatable Design
(WILEY ONLINE LIBRARY, 2009-07-13) Christopher Mutungi; Onyango Calvin; Jaros Doris; Henle Thomas; Rohm Harald
Cassava starch was debranched by treatment with isoamylase and pullulanase and the yield of resistant starch type III (RS III) optimized with respect to starch solids concentration (7.5-15%, w/v), incubation time (8-24 h) and enzyme concentration using central composite rotatable design. Higher concentrations of pullulanase (10-35 U/g starch) compared to isoamylase (30–90 mU/g starch) were required to give a similar degree of starch hydrolysis within the experimental domain. A clear debranching end-point was identifiable by following the reducing value, blue value and β-hydrolysis limit of cassava starches debranched using isoamylase. It was difficult to define a debranching endpoint of pullulanase treatment by these parameters due to contaminating α-D-(1→4) activity. The yield of RS III was significantly higher in isoamylolysates and increased steadily with increasing degree of hydrolysis to peak at 57.3%. Purification of the debranched material further increased the RS III yield to 64.1%. Prolonged (24 h) hydrolysis of cassava starch with high concentration of pullulanase (35 U/g) gave lower RS III contents in the purified (34.2%) and unpurified (36.2%) hydrolysates compared to 49.5 and 62.4%, respectively, at moderate pullulanase concentration (22.5 U/g) and incubation time (16 h).
Structural And Physicochemical Properties And In Vitro Digestibility of Recrystallized Linear Α-D- (1 → 4) Glucans Derived from Mild-Acid-Modified Cassava Starch
(Food Research Internationa, 2010) Mutungi C.; Onyango C.; Rost F.; Doert T.; Rohm H.; Jaaros D.
Molecular structure and recrystallization method influence the techno-functional behaviour of recrystallized starch as a functional ingredient in foods. The physicochemical properties of debranched and recrystallized mild-acid-modified cassava starch were studied. Cassava starch was treated with 0.14 mol/L hydrochloric acid for 24, 96 and 216 h at 40 °C prior to debranching with pullulanase. The debranched starches (DS) were recrystallized by annealing (ANN-DS), temperature-cycling (TC-DS) or heat-moisture treatment (HMT-DS) and the particle distribution, crystallinity, thermal properties, solubility, water binding and in vitro digestibility were analyzed. Acid treatment increased the fraction of linear α-d-(1 → 4) glucans comprising 13–30 monomers. Particles comprised loosely to firmly coalesced primary elements forming aggregates of mono- or bi-modal size distribution at ⩽5 μm and ⩾20 μm. The relative crystallinities ranged between 31.1–56.1%. Water binding decreased significantly with acid treatment whereas both solubility and water binding were influenced by the recrystallization method and decreased in the order: DS > ANN-DS > TC-DS > HMT-DS. Major thermal transitions occurred at 80– 130 °C and 130–160 °C, and the in vitro digestibility rates of 6.8–62.8% correlated significantly (p < 0.001) with relative crystallinity and melting enthalpy.
Rheological And Baking Characteristics of Batter and Bread Prepared from Pregelatinised Cassava Starch and Sorghum and Modified Using Microbial Transglutaminase
(Journal of Food Engineering, 2010) Onyango Calvin; Mutungi Christopher; Ubehend Gunter; Lindhauer Meinolf G
The effect of different concentrations (0, 0.5, 1 and 1.5 U/g) of microbial transglutaminase (MTG) on the creep-recovery properties of gluten-free batter prepared from pregelatinised cassava starch, sorghum and egg white was investigated. The test conducted in the rheometer had an instant loading of 80 Pa for 60 s and recovery of 0 Pa for 140 s. Increasing MTG concentration decreased the batters’ resistance to deformation and compliances but increased zero shear viscosity and elastic recovery. Changes in batter rheological properties were insignificant (P > 0.05) at MTG concentrations beyond 0.5 U/g. Crumb properties of gluten-free bread baked from the batter revealed that increasing MTG concentration increased (P < 0.05) crumb firmness and chewiness, whereas increasing incubation time decreased (P < 0.05) crumb cohesiveness, chewiness and resilience. There were no significant interaction effects (P > 0.05) between enzyme concentration and incubation time
Rheological And Textural Properties of Sorghum-Based Formulations Modified with Variable Amounts of Native or Pregelatinised Cassava Starch
(LWT - Food Science and Technology, 2011) Onyango Calvin; Mutungi Christopher; Ubehend Gunter; Lindhauer Meinolf G.
Sorghum bread was made from native or pregelatinised cassava starch and sorghum flour in the ratio 10:90, 20:80, 30:70, 40:60 and 50:50. The other ingredients, measured on flour-weightbasis, were water (100%), sugar (6.7%), egg white (6%), fat (2%), salt (1.7%) and yeast (1.5%). The dynamic oscillatory behaviours of the batters were affected by the amount and type of starch. In the amplitude sweep measurements, increasing concentration of native starch decreased storage modulus, whereas increasing concentration of pregelatinised starch increased the linear viscoelastic range of the batters. In the frequency sweep measurements, the loss factor of batters treated with native starch declined with increasing frequency. Batters treated with 10 or 20% pregelatinised starch showed declining loss factors, whereas batters treated with 40 or 50% pregelatinised starch showed increasing loss factors with increasing frequency. Sorghumbased batters containing native starch gave bread with better crumb properties than batters containing pregelatinised starch. Crumb firmness and chewiness declined with increasing native or pregelatinised starch concentration. Crumb adhesiveness of breads containing pregelatinised starch increased with increasing starch content but was not affected by native starch. Cohesiveness, springiness and resilience increased with increasing native starch content, but were minimally affected by increasing pregelatinised starch content.
Determinants of Stunting and Overweight among Young Children and Adolescents in Sub-Saharan Africa
(SAGE Publications, 2014-06-01) Keino, Susan; Plasqui, Guy; Ettyang, Grace; van den Borne, Bart
BackgroundStunting and overweight are nutritional problems affecting most of sub-Saharan Africa. The region now has the world's highest rate of stunting among children (43%), while overweight and obesity are becoming a global epidemic, and Africa is not spared. The past two decades have seen a dramatic increase in obesity in sub-Saharan Africa.ObjectiveThe purpose of this systematic review is to explore the determinants of stunting and overweight in sub-Saharan Africa.MethodsA literature search was conducted in PubMed using the key words stunting, overweight, obesity, Africa, sub-Saharan Africa, determinants, and prevalence. Limits were set to include articles published between 1990 and 2012. The systematic review resulted in 38 studies, and after selection based on title, content, and country of the study, 18 studies were eligible for this review. Data were analyzed by the chi-square test.ResultsThe prevalence rates of stunting and over-weight were dependent on socioeconomic, demographic, and environmental factors. Many studies indicate that male children and those living in a rural setting are more likely to be stunted, whereas overweight among children depends more on age, household composition, occupation of the mother, and the mother's body mass index. Stunting occurred together with overweight among both boys and girls from 1 to 5 years of age. Stunting was more prevalent among boys than among girls. Indicators of socioeconomic status, such as mother's education, mother's occupation, and household income, were some of the determinants directly linked to stunting, whereas environmental factors, such as rural or urban setting and sanitation, influenced both stunting and overweight. Concurrent stunting and overweight is influenced by maternal and household factors, such as maternal height, age, and education, large household size, and lower socioeconomic status.ConclusionsAlthough socioeconomic, demographic, and environmental factors were significant in determining stunting and overweight, other factors, such as nutrition and lifestyle, were important risk factors. Stunting in childhood is a risk factor that may result in overweight and obesity later in adolescence and adulthood, indicating the need to screen children below 1 year of age to identify stunting early in life. Promoting exclusive breastfeeding is reported to be important in preventing both stunting and overweight among children. More research is needed to explore the relationship between stunting and overweight and to explore policy guidelines to address the phenomenon.
Genetic Diversity of Kenyan Native Oyster Mushroom (Pleurotus)
(The Mycological Society of America, Lawrence, KS, 2015) Otieno Ojwang D.; Wamalwa Mark; Onguso Justus Mungare; Matasyoh Lexa G.; Wanjala Bramwel W.
Members of the genus Pleurotus, also commonly known as oyster mushroom, are well known for their socioeconomic and biotechnological potentials. Despite being one of the most important edible fungi, the scarce information about the genetic diversity of the species in natural populations has limited their sustainable utilization. A total of 71 isolates of Pleurotus species were collected from three natural populations: 25 isolates were obtained from Kakamega forest, 34 isolates from Arabuko Sokoke forest and 12 isolates from Mount Kenya forest. Amplified fragment length polymorphism (AFLP) was applied to thirteen isolates of locally grown Pleurotus species obtained from laboratory samples using five primer pair combinations. AFLP markers and internal transcribed spacer (ITS) sequences of the ribosomal DNA were used to estimate the genetic diversity and evaluate phylogenetic relationships, respectively, among and within populations. The five primer pair combinations generated 293 polymorphic loci across the 84 isolates. The mean genetic diversity among the populations was 0.25 with the population from Arabuko Sokoke having higher (0.27) diversity esti mates compared to Mount Kenya population (0.24). Diversity between the isolates from the natural population (0.25) and commercial cultivars (0.24) did not differ significantly. However, diversity was greater within (89%; P . 0.001) populations than among populations. Homology search analysis against the GenBank database using 16 rDNA ITS sequences randomly selected from the two clades of AFLP dendrogram revealed three mushroom species: P. djamor, P. floridanus and P. sapidus; the three mushrooms form part of the diversity of Pleurotus species in Kenya. The broad diversity within the Kenyan Pleurotus species suggests the possibility of obtaining native strains suitable for commercial cultivation.
Occurrence of Fusarium Head Blight of Wheat and Associated Mycotoxins in Narok and Nakuru Counties, Kenya
(Science and Eduacation Publishing, 2016) Wagacha John Maina; Njeru Nancy Karimi; Okumu Oliver Otieno; Muthomi James Wanjohi; Mutegi Charity Kawira
Fusarium head blight (FHB) is an important disease of small grain cereals. This study assessed the incidence and severity of FHB of wheat at hard dough stage, and levels of deoxynivalenol and T2-toxin at harvest by direct competitive enzyme linked immuno-sorbent assay. Wheat ears were randomly sampled from 51 farms in Narok County and 51 farms in Nakuru County at hard dough stage while wheat kernels were sampled at harvest. Prevalence of FHB in both Counties was 100%. The mean incidence of FHB was 28.4% and 20.5% in Narok and Nakuru Counties, respectively with 16.9% and 11.7% corresponding severity. Over 14 Fusarium spp. were isolated from wheat ears and kernels with F. avenaceum, F. poae and F. graminearum being isolated in the highest incidence. Levels of DON in the kernels ranged from below limit of detection n (
Occurrence of Fusarium Head Blight of Wheat and Associated Mycotoxins in Narok and Nakuru Counties, Kenya
(Science and Education Publishing, 2016) Wagacha, John Maina; Njeru, Nancy Karimi; Okumu, Oliver Otieno; Muthomi, James Wanjohi; Mutegi, Charity Kawira
Fusarium head blight (FHB) is an important disease of small grain cereals. This study assessed the incidence and severity of FHB of wheat at hard dough stage, and levels of deoxynivalenol and T2-toxin at harvest by direct competitive enzyme linked immuno-sorbent assay. Wheat ears were randomly sampled from 51 farms in Narok County and 51 farms in Nakuru County at hard dough stage while wheat kernels were sampled at harvest. Prevalence of FHB in both Counties was 100%. The mean incidence of FHB was 28.4% and 20.5% in Narok and Nakuru Counties, respectively with 16.9% and 11.7% corresponding severity. Over 14 Fusarium spp. were isolated from wheat ears and kernels with F. avenaceum, F. poae and F. graminearum being isolated in the highest incidence. Levels of DON in the kernels ranged from below limit of detection (
Effect of Cropping Systems on Accumulation of Fusarium Head Blight of Wheat Inocula in Crop Residues and Soils
(Journal of Plant Sciences, 2016-04-15) Njeru N.K.; Muthomi J.W.; Mutegi C.K.; Wagacha J.M.
Fusarium head blight (FHB) is an economically important disease of wheat, which causes reduction in grain yield both quantitatively through reduced seed weight and qualitatively by contaminating grains with mycotoxins. The effect of cropping systems on accumulation of FHB inocula in crop residues and soil was assessed at hard dough stage of wheat during the 2013 cropping season in three agro-ecological zones in Narok County, Kenya. A semi structured questionnaire was used to obtain information on wheat production practices. Fusarium spp. were isolated from crop residues and top soil, while incidence and severity of FHB were assessed at mid-anthesis. Majority of the wheat farmers were small scale producers who rotated wheat with maize, grew the two crops in adjacent fields, grew wheat in consecutive years, left wheat residues as standing hay for livestock and practiced simple land preparation methods. Prevalence of FHB was 100%, while mean incidence and severity were 20.7 and 28.4%, respectively. The most frequently isolated Fusarium spp. were F. chlamydosporum and F. graminearum in crop residues and F. oxysporum and F. proliferatum in soil. The incidence of Fusarium spp. in soil and crop residues was highly correlated to FHB incidence but not to severity of the disease. Wheat production practices affect the survival of Fusarium spp. in soil and crop residues between cropping seasons. It is therefore, recommended that after harvesting, wheat straw and maize stover should be removed from the field or be incorporated into the soil through tillage to allow faster decomposition. Inclusion of maize as a rotation crop in wheat production should also be avoided.
Effect of Cropping Systems on Accumulation of Fusarium Head Blight of Wheat Inocula in Crop Residues and Soils
(Academic Journals Inc., 2016-12-21) Njeru, N.K.; Muthomi, J.W.; Mutegi, C.K.; Wagacha, J.M.
Fusarium head blight (FHB) is an economically important disease of wheat, which causes reduction in grain yield both quantitatively through reduced seed weight and qualitatively by contaminating grains with mycotoxins. The effect of cropping systems on accumulation of FHB inocula in crop residues and soil was assessed at hard dough stage of wheat during the 2013 cropping season in three agro-ecological zones in Narok County, Kenya. A semi structured questionnaire was used to obtain information on wheat production practices. Fusarium spp. were isolated from crop residues and top soil, while incidence and severity of FHB were assessed at mid-anthesis. Majority of the wheat farmers were small scale producers who rotated wheat with maize, grew the two crops in adjacent fields, grew wheat in consecutive years, left wheat residues as standing hay for livestock and practiced simple land preparation methods. Prevalence of FHB was 100%, while mean incidence and severity were 20.7 and 28.4%, respectively. The most frequently isolated Fusarium spp. were F. chlamydosporum and F. graminearum in crop residues and F. oxysporum and F. proliferatum in soil. The incidence of Fusarium spp. in soil and crop residues was highly correlated to FHB incidence but not to severity of the disease. Wheat production practices affect the survival of Fusarium spp. in soil and crop residues between cropping seasons. It is therefore, recommended that after harvesting, wheat straw and maize stover should be removed from the field or be incorporated into the soil through tillage to allow faster decomposition. Inclusion of maize as a rotation crop in wheat production should also be avoided.
Farmer centered large scale e-surveillance and control of crop pests in Kenya
(2017) Awuor, Fredrick Mzee; Otanga, Sarah Atenya
With advancement of mobile technology and the property of mobile phones of being ubiquitous and pervasive, innovative applications in agriculture that are context specific and individualized to farmers’ needs can now be developed. This is because mobile phone based agricultural innovations are readily leveraged to provide farmers with information ranging from farm preparation and pre-harvest to post harvest and farm produce marketing. In this regard, this paper proposes a farmer centric pest e-surveillance solution framework, a digital platform that uses mobile devices, image processing and crowdsourcing to assist smallholder farmers in low income countries to effectively identify and control crop pest invasion, and to connect them with local agro-vet stores and extension service providers for assistance. This way, we can assist small holder farmers in rural Africa to learn about crop pests, to detect and respond to pest invasion, and to control the effects of such pest invasion by providing timely, accurate, relevant and readily consumable information in the local languages of the farmers. This also makes it easy to perform large-scale pest surveillance in the rural farming community
Prevalence of Fasciolosis in Cattle, Sheep, and Goats Slaughtered in Slaughter Slabs in Trans-Nzoia West, Kenya. and Knowledge of Livestock Handlers
(Journal of Biology, Agriculture and Healthcare, 2017-03-01) Musotsi, Protus; Otieno, Christina; Njoroge, Simon
Background: Fasciolosis is known globally to be an important helminthic disease of ruminants caused by liver fluke species of the genus Fasciola, and it is one of the most neglected tropical zoonotic diseases that can lead to human infection. It has the widest geographic spread of any emerging zoonotic disease, and it occurs in many countries of the world. Objectives: The study aimed at determining the prevalence of fasciolosis in ruminants slaughtered in Trans-Nzoia West. Specific objectives were to establish the trend of fasciolosis in ruminants, ascertain the relationship between fasciolosis prevalence and rainfall patterns and assess the knowledge of meat sellers and farmers about fasciolosis. Methodology: A 5-year secondary data retrospective study was carried out in Trans-Nzoia West, Trans-Nzoia County. The study population consisted of ruminants slaughtered, meat sellers and livestock farmers.Results: A total of 104,221 cattle, sheep and goats were slaughtered in the five-year period in which 6,098 (5.85%) were infested with fasciolosis with a prevalence of 6.52%, 6.08% and 4.10% in cattle, sheep, and goats respectively. Most meat sellers (72.2%) were able to identify fasciolosis in infested livers, 88.9% reported liver flukes infestation resulted in the loss of income while 58.3% were not aware of nutrition depletion associated with fasciolosis. Of the farmers interviewed, 52.9% grazed in swampy areas, 66.7% dewormed after 3 months, 78.4% had heard about fasciolosis and 80.0% did not know the cause of fasciolosis. The majority (95.0%) were not aware of the snail species spreading liver flukes while 77.5% did not know that fasciolosis was a zoonotic disease.Conclusion: Fasciolosis was prevalent in the area and caused great economic loss to the meat sellers. Most farmers were not aware of its cause and zoonotic nature. Recommendations: Fasciolosis control should be approached from a multidisciplinary angle and farmers should be educated on it and its zoonotic nature.
Increasing food security and nutrition resilience in response to climate change in east Africa: findings from a multisectoral symposium
(Elsevier, 2017-04-01) Braitstein, Paula; Lama, Tenzin; Keino, Susan; Gladanac, Branka; Yego, Faith; Cole, Donald; Tabu, John Simiyu; Cortinois, Andrea; Tarus, Carren; Fox, Ann
BackgroundThe symposium Kuwa Tayari (“be prepared” in English): finding pathways to nutrition and food security resilience in response to climate change in East Africa was held in Eldoret, Kenya, in May, 2016. The goals of this symposium were to increase awareness, stimulate research ideas and recommendations, catalyse the development of training opportunities, and provide an evidence base for policy and decision-making in these regions in preparation for, and response to, our changing world. Here, we describe the structure, aims, and outcome of the symposium.MethodsThe 2-day symposium was a partnership initiative between University of Toronto Dalla Lana School of Public Health in Toronto, Canada, and Moi University, College of Health Sciences, School of Public Health in Eldoret, Kenya. Target audiences were scientists, students, and educators in public health, environmental studies, agriculture, agroecology, civil society, non-government organisations, and government stakeholders. Symposium organisers did a literature review to develop a background paper that helped inform the selection of five planetary health subthemes of the symposium: (1) agriculture, nutrition, and agro-biodiversity; (2) water security; (3) renewable and sustainable cooking fuels; (4) nutrition and food security issues affecting vulnerable populations; and (5) human rights and sustainable development. The symposium format consisted of keynote and oral abstract presentations, plenary discussions, small group work, poster viewing sessions, and networking opportunities. A final report was produced to highlight key outcomes and recommendations.FindingsThere were 121 attendees at the symposium from 26 institutions in Kenya, Uganda, Canada, USA, and elsewhere; most were from academic and community organisations. Participants' reasons for attending were met: personal growth and development, networking, research, course and training ideas, and potential collaborations. There was consensus on the need to invest in innovative, context-specific, climate-smart agricultural practices that support sustainable livelihoods and development, and improve food security at the household level throughout east Africa.InterpretationMultisectoral, transdisciplinary, community-based, and population health research and interventions are needed to address the complex and interconnected issues of climate change, nutrition, and food security. Within east Africa, participatory initiatives that engage vulnerable populations (such as women, pastoral populations, and the urban poor), and those that integrate indigenous food system practices are crucial. Training priorities should be in the areas of integration of climate change topics into existing public health curriculums, and novel interdisciplinary courses on planetary health.FundingCanadian Institutes of Health Research.
Farmers’ perceptions and coping strategies with sweet potato weevil and characterization of sweet potato genotypes for diversity and resistance to cylas puncticollis boheman in kenya
(2018) Ochieng, Lilian Anyango
Sweet potato (Ipomoea batatas (L.) Lam.) contributes significantly to food security and income of subsistence farmers in Kenya. However, productivity of the crop is constrained by several biotic, abiotic and socio-economic factors. Amongst the biotic constraints, insect pests such as the sweet potato weevil (Cylas spp.) cause significant yield losses. However, in Kenya, there is limited information on farmers’ perception and management of Cylas spp. and on diversity among cultivated sweet potato genotypes. The objectives of this study were to: (i) Assess farmers’ perceptions and coping strategies to the sweet potato weevil; (ii) Analyze variation among selected sweet potato genotypes using agro-morphological, molecular and nutritional characters, and; (iii) Screen selected sweet potato (Ipomea batatas L.) genotypes for resistance to the sweet potato weevil. Firstly, participatory rural appraisal approach was conducted in the year 2012 in Homa Bay County where 269 farmers were interviewed on farmers’ perceptions and coping strategies against the sweet potato weevil (Cylas spp.). This study revealed that Cylas spp. was the most problematic (93.3%) pest. Many farmers (90.7%) were not aware of sweet potato genotypes that had field resistance to Cylas spp. The most commonly used methods by farmers to manage Cylas spp. were reridging during weeding (21.2%) followed by covering exposed roots with soil (12.6%). Secondly, field experiments were conducted on-station in 2014 at two sites (ATC - Miyare and -KALRO Embu) using 68 sweet potato genotypes arranged in a Randomized Complete Block Design. Data were recorded on variation in agromorphological, molecular and nutritional characters. On the basis of quantitative agromorphological traits, Analysis of variance revealed significant (p≤0.05) differences among sweet potato genotypes. Genotypes Nyautenge (16.82 t/ha) and Kemb 10 (17.04 t/ha) had the highest average root yield at ATC Miyare and KALRO Embu respectively while, genotypes 56682-03 (0.84 t/ha) and K/KA/2004/215 (1.07 t/ha) had the least average root yield at ATC -Miyare and KALRO -Embu respectively. The genotypes were variable in respect to all qualitative traits studied. Both quantitative and qualitative based dendrograms did not group the genotypes according to geographical area of origin or shared names. On molecular approach, 13 simple sequence repeat (SSR) markers were used to determine genetic relationship among the sweet potato genotypes. The SSR markers were highly polymorphic (0.2723) and cluster analysis divided the genotypes into two major groups. However, the genotypes did not form specific groups according to geographic regions or shared names. Nutrionally, the genotypes significantly (p≤0.0001) differed in dry matter, root protein, root carotenoids, root sucrose and root starch contents but dendrograms did not group the genotypes in relation to their origin or shared names. Genotype Nyautenge had a stable high yield (16.82 t/ha at ATC -Miyare and 15.23 t/ha at KALRO -Embu) and high dry matter content (40.14% at ATC -Miyare and 32.26% at KALRO -Embu) at both sites. However, the same genotype rated very low in other equally important nutrients like total carotenoids and sucrose contents at ATC -Miyare and KALRO -Embu. Genotypes Kenspot 1, Saly boro, 91/2187, 9 Nduma, Kenspot 3 and Kenspot 2 had high dry matter contents at both sites and hence recommended for inclusion in future breeding xix programmes. Thirdly, fifty-one selected sweet potato genotypes were evaluated for their resistance to Cylas punticollis Boheman (Coleoptera: Brentidae) in a controlled experiment of no-choice arena from November, 2015 to February, 2016. The 51 evaluated genotypes were significantly (p≤0.0001) different in their resistance to C. puncticollis damage. The study revealed that no genotype was completely resistant to weevils but genotypes Obugi (5.00 adults) and 5 Nyandere (5.00 adults) were the highly resistant to C. puncticollis while genotypes Tainung (25 adults), Naspot 1 (24.33 adults), Kenspot 5 (22.67 adults) and Fundukhusia (22.67 adults) were the most susceptible to C. puncticollis damage. Resistance to weevils was negatively correlated (-0.71) to dry matter content and positively correlated to starch (0.46) and sucrose (0.48) contents. In conclusion, genotype Obugi is a stable high yield performer (9.21 t/ha and 9.55 t/ha in ATC -Miyare and KALRO -Embu respectively) and has a high resistance to C. puncticollis as compared to Naspot 1 (susceptible check) and Santo Amaro (resistant check). Other genotypes rated in this study as medium resistant to C. puncticollis and had earlier recorded high yields at KALRO -Embu are Santo Amaro (11.49 t/ha) and Wera (9.22 t/ha). However, these genotypes recorded low yields in ATC -Miyare and thus may not be suitable for ATC -Miyare site and its surrounding. Genotype Tainung was found to be the most inadequate since it was the most susceptible (25 adults) to weevils, low performing in yield (1.44 t/ha at ATC -Miyare and 5.70 t/ha at KALRO -Embu) and was low in dry matter content (21.40% at ATC - Miyare and 24.39% at KALRO -Embu) as compared to others. All the above-mentioned traits can make the genotype not to be preferred by many farmers. Nonetheless, the genotype has got a high carotenoid content (27.55 µg/g at ATC Miyare and 30.57 µg/g at KALRO Embu) as compared to other genotypes and thus suitable for addressing vitamin A defficiency in the society.
Tobacco, the Labour Bottleneck and Politics of Food Security in Sirisia, Bungoma County, 1975-2005
(Center for Promoting Ideas, USA, 2018-05) Joseph W, Ndalilah; Makana, Professor Nicholas E.; Tanui, Dr. Priscah
The study investigated the impact of tobacco on food security in Sirisia, Bungoma County using the concepts of innovation, adaptation and commercialization. The study applied these concepts to explain how the tobacco scheme was built upon a repressive and sustained work regime among peasants at the expense of food production. The concept of innovation embraces the dynamism of African peasants and therefore, contradicts analyses that portray them purely as an amorphous mass of subsistence cultivators. Adaptation on the other hand was used to explain the copying mechanisms and the link between indigenous forms of production and the ideas, techniques and new approaches introduced by the agents of capitalism. Commercialization presupposes the changes embraced by African peasant households in response to market forces. Sirisia, accordingly, is an illustration of this state of affairs particularly in our analysis of the impact of tobacco cultivation on food security trends in the period 1975 to 2005. The paper holds that with tobacco commercialization, tobacco labour demand and food insecurity were inextricably intertwined. To survive, peasants had to take on specific strategies to overcome food deficits. The paper was based on archival research, oral interviews as well as analyzing literature on tobacco in history.
Heavy Metals in Pig Livers; A Case of Munyaka Estate-Uasin-Gishu County, Kenya
(African Journal of Education, Science and Technology, 2018-06-02) Cherop, Cleophas K.; Otieno, Christina A.; Koskei, Peter
have lead to alteration of their natural geochemical and biochemical cycle and balance. The risk of heavy metal contamination in meat/pork is of public health concern for both food safety and human health. The study aimed at determining the levels of lead, cadmium and mercury in pigs reared in two husbandry systems in Uasin-Gishu County, Kenya. A comparative cross-sectional study was employed. Thirty two pigs representing close to a thousand pigs in Munyaka estate were studied under two husbandry systems. Four branded manufactured feeds and 6 forage plants were analyzed by AAS machine for lead, cadmium and mercury. Results were summarized using means. The mean levels of lead, cadmium and mercury among intensively produced pigs were 0.10±0.04, 0.13±0.04 and 0.12±0.04mg/kg.wet weight respectively. The mean levels of lead, cadmiu and mercury in extensively produced pigs were 0.09±0.03, 0.18±0.05 and 0.14±0.09mg/kg.wet weight respectively. There was a significant difference (p<0.05) in cadmium levels in pigs under intensive and extensive husbandry system with extensively produced pigs having higher levels. Manufactured feed B had mean Pb levels of 0.26±0.01mg/kg.dry weight while feed D had Pb levels of 0.38±0.02mg/kg.dry weight. Cabbage leaves had mean Pb levels of 0.60±0.26 mg/kg.dry weight whereas grass on the roadside had mean Hg levels of 0.03±0.02mg/kg.dry weight with banana peelings also having mean Hg levels of 0.03±0.04mg/kg.dry weight. There was a significant difference (p<0.05) in cadmium levels in pigs under intensive and extensive husbandry systems with extensively produced pigs having higher levels. The study showed that pig livers under the study were not safe for human consumption due to the presence of mercury levels above the WHO maximum recommended levels. These metals are known to cause adverse health effects including neurological and renal disturbances neurological and renal disturbances. The Government shoul strictly enforce The Animal Diseases Act; Cap364 on prohibition of extensive husbandry system. Kenya bureau of standards (KEBS) and Department of Veterinary Services (DVS) should regularly monitor and evaluate pork to safeguard human health. Farmers should be educated on the need to discriminately use of Phosphatic fertilizers and pesticides as they contribute to HMs in the soil and the consequent uptake by plants.
Screening of Warburgia Ugandensis Crude Extracts Obtained from Different Organic Solvents against Tomato Phytophthora Infestans and Alternaria Solani
(European Academic Research, 2019-03) Kamau Esther Waithira; G.E Mworia; J.M Maingi; P.W Masinde
Alternaria solani and Phytophthora infestans are causative agents of early and late blight of tomatoes respectively which are currently controlled using fungicides. Overuse of fungicides poses safety concerns. The research objective was to investigate the invitro efficacy of Warburgia organic solvent crude extracts on blight pathogens. Warburgia ugandensis stem bark sample was air dried at room temperature then ground. The powdered material was weighed and soaked in organic solvent then filtered and the solvent recovered using a rotary evaporator. Multiple extraction method was used with four organic solvents. Well diffusion method was used to screen Warburgia extracts against A. solani and P. infestans. All assays were performed in triplicate. Statistical analysis on inhibition zone was carried out using analysis of variance (ANOVA). Warburgia ugandensis hexane crude extract had the highest inhibition zone in A. solani while methanol crude extract gave the highest mean inhibition zone in P. infestans. All the extracts were inhibitive against P. infestans and A. solani. Further studies are required for invivo studies and to analyze the bioactive compounds in the extracts.
Modulation of Aflatoxin Production by Interaction of Aspergillus Species from Eastern Kenya
(IOSR Journal of Environmental Science, 2019-04-13) Lagat Micah Kipkemboi; Toroitich Faith Jebet; Obonyo Meshack Amos; Makonde Huxley Mae
Aflatoxin contamination of grain has continued to pose a significant threat to sustainable food security and trade worldwide. In the field, there are incidences of varying contamination levels in grain within the same niche. We hypothesize that the variation could be due to fungal species interaction at the kernel level. Seventeen isolates (14 Aspergillus flavus and 3 Aspergillus parasiticus) from Eastern Kenya were selected and confirmed for toxigenicity using Dichlorvos-Ammonia method, then cultured based on their isolation frequencies and co-existence in nature. The fungi were co-cultured using maize kernels as growth substrate, which was then used to estimate aflatoxin produced in a competitive ELISA. A one-sample two-tailed t-test was carried out to determine the degree of significance in aflatoxin production. Eight isolates were non-toxigenic, while nine were toxigenic. When co-cultured with some non-toxigenic isolates such as A. parasiticus (2EM0601), the most toxigenic A. flavus isolate (1EM1901) significantly increased aflatoxin production, while it reduced with others. These observations warrant investigation on the interaction of Aspergillus species in culture especially given their diverse toxigenic potential. We concluded that colony-mediated aflatoxin production could explain the variations of toxin levels observed in freshly collected field samples.
Influence of socio‐economic and agronomic factors on aflatoxin and fumonisin contamination of maize in western Kenya
(Wiley Periodicals, Inc., 2019-05-08) Njeru, Nancy Karimi; Midega, Charles Aura Odhiambo; Muthomi, James Wanjohi; Wagacha, John Maina; Khan, Zeyaur Rahman
Consumption of maize contaminated with mycotoxins has been associated with detrimental health effects. A farm survey covering 116 push‐pull and 139 non‐push‐pull cropping systems was conducted to determine the socio‐economic and agronomic factors that influence farmers’ knowledge on incidence and contamination of maize by ear rots and associated mycotoxins in western Kenya. All the respondents were smallholder farmers between the ages of 23 and 80 years, with 50% of them being female. Maize samples were collected from the standing crop in the field of each interviewed farmer and analyzed for aflatoxin and fumonisin. Only a small proportion of farmers had knowledge of aflatoxin and ear rots in maize. Overall, less than 20% of maize samples were contaminated with both aflatoxin and fumonisin, and more maize samples were contaminated with fumonisin as compared to aflatoxin. Proportions of maize samples containing higher than the acceptable Kenyan regulatory threshold (10 µg/kg) for aflatoxin and European Commission regulatory threshold (1,000) µg/ kg for fumonisin were lower in maize samples from push‐pull cropping system. Age of farmer and county of residence were significantly and positively associated with knowledge of aflatoxin, while cropping system, county of residence, and level of education were positively associated with knowledge of maize ear rots. There was strong correlation between knowledge of maize ear rots and knowledge of aflatoxin. Levels of both aflatoxin and fumonisin were significantly and positively associated with the use of diammonium phosphate (DAP) fertilizer at planting. Aflatoxin levels were also positively associated with stemborer damage. Agronomic practices were not significantly different between push‐pull and non‐push‐pull farmers. However, use of DAP fertilizer was the most important agronomic factor since it was associated with both aflatoxin and fumonisin contamination of maize. These results imply that creating awareness is key to mitigation of ear rots and mycotoxin contamination of maize. The results also suggest that the levels of aflatoxin and fumonisin in maize in western Kenya were influenced both by pre‐harvest agronomic practices and by the cropping system adopted, push‐pull or not.
A Comparative study of the household food access by farmers in Farmer Field and Life Schools in Gatanga Constituency, Murang’a County, Kenya
(African scholarly science communications trust, 2019-06) Kimani, AM; Were, GM; Ndege, SK
Many programs have been initiated to assist farmers diversify food production. The Farmer Field and Life Schools (FFLS), an agricultural extension methodology, is an example. Dietary assessment methods are used for nutrition assessments. This study compared household food consumption patterns, by using the Household Dietary Diversity Score (HDDS) of households who participated in the FFLS at baseline and after intervention and Non-FFLS households in the Gatanga Constituency in Murang’a County. The study was based on a United Nations Joint Program implemented from 2009 to 2013. A comparative cross-sectional design was used in this study to compare FFLS at baseline, after intervention and Non-FFLS households. 112 households (56 for cases and 56 for comparative group) participated in this study. The baseline survey with 390 households was in 2009. Data was analysed using the Statistical Package for Social Science (SPSS) version 21. Paired and independent T-Tests were used to determine the difference in the household dietary diversity score between FFLS at baseline and after intervention, and post intervention FFLS and Non-FFLS, respectively. Results show that 42.8% (n=56) of the FFLS households and 28.5% of non-FFLS household respondents were over 50 years of age. 49% of FLS and 11% non FFLS households have incomes ranging from 0-5,000 Ksh. per month, with 41% of FFLS and 32% non FFLS having incomes ranging from Ksh. 5,001- 10,0001 . Mean for Household Dietary Diversity Score (HDDS) at baseline was 8.16 and Non-FFLS was 8.45. Minimum food groups consumed across all groups were cereals, milk and milk products, oils and fats. Comparing FFLS at baseline and post intervention, the percentage of households consuming all food groups increased with exception of fruits and meat. There was a significant difference (p=0.007 against p<0.0005) in the HDDS when FFLS groups post intervention were compared with their baseline. There was no significant difference (p=0.176, against p<0.0005) in the HDDS between FFLS post intervention and non-FFLS households. Compared with the baseline information, FFLS participants who were of low economic status improved their HDDS. Targeting of vulnerable households to participate in such programs has the potential of improving their HDDS compared with the regular HDDS population. Integration of nutrition in agricultural programs with strong extension systems like the - has great potential to improve access and consumption of diversified foods for vulnerable households.

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