Department of Chemistry: Recent submissions
Now showing items 181-200 of 337
-
Spatial distribution and temporal trend in concentration of carbofuran, diazinon and chlorpyrifos ethyl residues in sediment and water in Lake Naivasha, Kenya
(Springer, 2012)Chlorpyrifos ethyl was found to be widely distributed in water and sediment in Lake Naivasha. Higher levels were reported in sediment (11.2–30.0 ng g-1 dry weight (dw) in wet season than in dry season (4.7–17.4 ng g-1 ... -
Quality and yields of black tea Camellia sinensis (L.) O. Kuntze responses to harvesting: A review on experiences from Kenya
(PBS Journals, 2012)Tea beverages, from tender shoots of Camellia sinensis L., are the most widely consumed fluids after water. The young tender shoots of the plant are harvested using various plucking methods. Incorrect plucking leads to ... -
Effects of Production Locations and Plucking Intervals on Clonal Tea Fatty Acids Levels in the Kenya Higlands
(J-STAGE, 2012-05-01)Tea leaves contain unsaturated fatty acids which are precursors of aroma compounds. Despite uniform plucking practices in Kenya, plain black tea quality varies with locations. Variations in tea aroma and/or precursors ... -
Phytoecdysteroids from the stem bark of Vitex doniana and their anti-inflammatory effects.
(Planta Medica, 2013)With reference to the ethnopharmacological significance of Vitex doniana Sweet (Lamiaceae) leaves in the treatment of stomach and rheumatic pains as well as inflammatory disorders, biological studies on its stem bark ... -
Influence of Location of Production, Season and Genotype on Caffeine and Flavan-3-ols in Young Green Tea (Camellia sinensis) Leaves in Kenya
(David Publishing Company, 2013)Although tea is grown in agro-ecological regions widely varying in environmental factors affecting yield and quality, planters usually import genetic materials across the different growing regions assuming genotypes with ... -
Effect of genotypes in different tea-growing locations in Kenya on some micronutrients content of black tea.
(International Society of Tea Science, 2013)Human beings and plants require essential elements for normal physiological functions and survival. Tea beverages are the most widely consumed fluids after water. If the beverages have appreciable levels of micronutrients, ... -
The response of clone BBK 35 tea to nitrogen fertilizer rates and harvesting intervals in the lake Victoria basin of Kenya.
(CAB International, 2013-01-01)Tea is an economic crop in the Lake Victoria basin of East Africa, earning high foreign exchange and creating employment opportunities especially in the rural poor regions. It is grown under varying environments causing ... -
Impacts of climate-induced changes on the distribution of pesticides residues in water and sediment of Lake Naivasha, Kenya
(Springer Netherlands, 2013-03-01)This study reports evidence of increased chlorpyrifos contamination in sediment and water in Lake Naivasha following its intensive application in the horticultural farms in the catchment area. Analytical results show that ... -
Voulkensin C–E, new 11-oxocassane-type diterpenoids and a steroid glycoside from Caesalpinia volkensii stem bark and their antiplasmodial activities
(Pergamon, 2013-05-15)A bioassay guided isolation of potential antimalarial molecules from the stem bark of Caesalpinia volkensii Harms (Fabaceae) achieved three new 11-oxocassane-type diterpenoids named voulkensin C (1), D (2) and E (3) together ... -
Effects of Senna didymobotrya root extract and compounds on tritoninduced hyperlipidaemic rats and differentiation of 3T3-Li preadipocytes
(Bentham Science Publishers, 2013-11-03)he lipid lowering effects of Senna didymobotrya (Leguminoceae) root extract (250 mg/kg) and pure isolates (100 mg/kg) were investigated for hypolipidemic activity on Triton-induced hyperlipidemic rats (in-vivo). The extracts ... -
Effect of genotypes in different environments on micronutrient content of black tea
(bio publisher, 2014-02-08)Essential elements are needed in the day to day living of both human beings and the plants including tea (Camellia sinensis). Different clones of tea have been developed and distributed to farmers in various locations ... -
Assessment of organochlorine pesticides (OCPs) contamination in relation to physico-chemical parameters in the Upper River Kuja Catchment, Kenya (East Africa)
(2019)Concentrations of 17 organochlorine pesticides residues (alpha-HCH, beta-HCH, gamma-HCH, deltaHCH, Heptachlor, Aldrin, Endrin, Endosulfan I, Dieldrin, p,p’-DDT, Endosulfan II, p,p’-DDD, Endrin aldehyde, p,p’-DDE, Endosulfan ... -
Evidence of non-DDD pathway in the anaerobic degradation of DDT in tropical soil
(Springer Berlin Heidelberg, 2019-03-01)DDT transformation to DDD in soil is the most commonly reported pathway under anaerobic conditions. A few instances of DDT conversion to products other than DDD/DDE have been reported under aerobic conditions and hardly ... -
Monitoring the occurrence and distribution of selected organophosphates and carbamates pesticide residues in the ecosystem of Lake Naivasha, Kenya
(Taylor & Francis, 2014-08-07)Although use of pesticides is critical in agricultural production, their residues present a potential risk to non-target organisms and lower the quality of surface water. In Kenya for instance, widespread use of pesticides ... -
Elucidating the causes of low phosphorus levels in ferralsols of Siaya County, Western Kenya
(Academic Journals, 2015-09-01)Low available soil phosphorus (P) is one of the factors limiting crop production in western Kenya. Availability of soil P depends on amount of apatite, addition of P fertilizers, P fixing potential of a soil, soil water ... -
Bioactive carbazole alkaloids from Alysicarpus ovalifolius (Schumach)
(The Korean Society for Applied Biological Chemistry, 2015-12-01)Phytochemical and biological evaluation of the stem bark of Alysicarpus ovalifolius led to the isolation of three carbazole alkaloids identified as mohanimbine (1), koenimbine (2) and koenidine (3) along with quercetin ... -
Effects of cropping systems and agricultural lime on soil properties and nutrient content of sugarcane on acidified soils of Kisumu County, Kenya
(American Journal of Agriculture and Forestry, 2016-07-23)Acid soils cause soil fertility problems such as Al and Mn toxicity, Ca, Mg, N deficiency and P fixation. These are constraints to high crop yields. Historically, liming is the common management practice used to neutralize ... -
Assessment of Levels of Nutrients in Selected ALVs at Different Harvesting Stages and Locations of Production in Western Kenya
(International Journal of Biochemistry Research & Review, 2019)Proper nutrition contributes to declines under-five mortality rates and improves the productivity of adults. Addressing nutritional problems requires adequate information on the diets of individuals and populations. African ... -
Chemical constituents of Ocimum kilimandscharicum Guerke acclimatized in Kakamega Forest, Kenya
(Chemical Society of Ethiopia, 2019)The genus Ocimum belongs to the Lamiaceae family and is made of almost 200 species of herbs and shrubs which have potential medicinal properties. The species are native to the tropical and temperate climate zones around ... -
Selected heavy metal levels in water and fish from winam gulf in Lake Victoria near Kisumu city, Kenya
(International Journal of Environmental and Ecology Research, 2019)Lake Victoria is the largest freshwater and fishery lake in Africa. Kisumu City, located at the shore of Winam Gulf has industrial activities discharging effluents into the lake with potential of contaminating the lake ...