Department of Chemistry: Recent submissions
Now showing items 301-320 of 339
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Spatial distribution and habitat characterization of mosquito species during the dry season along the Mara River and its tributaries, in Kenya and Tanzania
(Bio Med Central, 2018-12)Vector-borne diseases are increasingly becoming a major health problem among communities living along the major rivers of Africa. Although larger water bodies such as lakes and dams have been extensively researched, ... -
Effects of land use change on land degradation reflected by soil properties along Mara River, Kenya and Tanzania
(Scientific Research Publishing, 2015-01-01)Human-induced changes to natural landscapes have been identified as some of the greatest threats to freshwater resources. The change from natural forest cover to agricultural and pastoral activities is rampant especially ... -
Comparative evaluation of ELISA kit and HPLC DAD for the determination of chlorpyrifos ethyl residues in water and sediments
(Elsevier, 2013-12-15)Enzyme linked immunosorbent assay (ELISA) kit is a versatile, cheap and relatively available tool that can be used in remote areas. In this study, performance of ELISA kit was evaluated in terms of accuracy, recovery, ... -
Variation in catechin composition of popularly cultivated tea clones in East Africa (Kenya)
(2013)Variation in catechin composition of popularly cultivated tea clones in East Africa (Kenya) -
7α-Acetylugandensolide and antimicrobial properties of Warburgia ugandensis extracts and isolates against sweet potato pathogens
(Elsevier, 2011-06-15)7α-Acetylugandensolide together with thirteen known drimane-type sesquiterpenes have been isolated from Warbugia ugandensis bark extracts. Their structures were established by spectroscopic and physical methods as well ... -
Variation in indoor levels of polycyclic aromatic hydrocarbons from burning various biomass types in the traditional grass-roofed households in Western Kenya
(Elsevier, 2011-07-31)Biomass burning as fuel in the traditional grass-roofed rural households of Western Province of Kenya in open fire places, in poorly ventilated conditions, lead to accumulation of soot under the roofs. This study ... -
The influence of geographical area of production and nitrogenous fertiliser on yields and quality parameters of clonal tea
(2010-04-01)Variations in requirements for tea production in Kenya and factors controlling growth and production of secondary metabolites responsible for the quality parameters are indicative of the need for non-uniform recommendations. ... -
Antinociceptive and antiplasmodial activities of cassane furanoditerpenes from Caesalpinia volkensii H. root bark
(Elsevier, 2012-01-01)The chloroform and ethyl acetate extract (100mg/kg) of Caesalpinia volkensii H. exhibited significant (P≤ 0.05) antinociceptive activities using hot plate and writhing tests in mice while the later showed antiplasmodial ... -
Influence of region of production on relative clonal plain tea quality parameters in Kenya
(Elsevier, 2010-04-01)Tea is grown in diverse regions with varying climates. Growers seek high-yielding and superior quality cultivars to improve profitability of the enterprise. A superior quality genotype in one location is assumed to ... -
Flavour volatiles of Assam CTC black teas manufactured from different plucking standards and orthodox teas manufactured from different altitudes of Darjeeling
(John Wiley & Sons, Ltd, 1988-01-01)Biochemical correlations between volatile flavour constituents (VFC) of CTC bluck teas manufactured from fine and coarse plucking of Assam tea and orthodox teas fiom three different altitudes were carried out by GC-MS. ... -
The use of green tea (Camellia sinensis) leaf flavan-3-ol composition in predicting plain black tea quality potential
(Elsevier, 2007-12-13)Reliable and quantifiable green leaf parameters for predicting black tea quality potential of tea bushes at the single bush stage are necessary to shorten tea breeding and clonal selection programmes. Green leaf ... -
The changes in black tea quality due to variations of plucking standard and fermentation time
(Elsevier, 1998)Catechin levels in green leaf, total theaflavins, brightness, thearubigins, colour, flavour index and sensory evaluation decrease with coarse plucking standard in clone 6/8. The sum of Group I volatile flavour compounds ... -
The effects of altitude on the chemical composition of black tea
(John Wiley & Sons, Ltd, 1990-01-01)Changes in quality parameters of crush, tear and curl (CTC) black clonal teas due to variations in altitude within a radius of 10 km were determined. There were significant (P= 0.05) changes in all the quality parameters ... -
Changes in thearubigin fractions and theaflavin levels due to variations in processing conditions and their influence on black tea liquor brightness and total colour
(Elsevier, 2004-03-30)Increase in coarser plucking standards significantly (P< 0.05) depressed levels of theaflavin (TF; μmol/g), total colour and brightness (spectrophotometer) of black tea. But total thearubigins (TR) TRSI, TRSII and ... -
Influence of region of production on clonal black tea chemical characteristics
(2008-05-01)Production of black tea from the same vegetatively propagated (VP) cultivars, in Kenya and Malawi, shows variations in both chemical composition and quality. Whereas it is possible to produce black teas with similar ... -
Correlation of theaflavins content and valuations of Kenyan black teas
(John Wiley & Sons, Ltd, 1986-05-01)Correlation between theaflavins content and tasters' valuations of Kenyan black teas generally give positive but statistically non-significant correlation coefficients. In 105 correlations using 12 samples each, only ... -
Changes in the chemical and sensory quality parameters of black tea due to variations of fermentation time and temperature
(Elsevier, 2001-12-31)The changes in theaflavins and residual catechin compositions, thearubigins TRSI and TRSII, sensory characteristics of total colour, brightness and briskness of black tea were investigated. It was demonstrated that the ... -
Flavanol composition and caffeine content of green leaf as quality potential indicators of Kenyan black teas
(1997)The Ñavanol composition and ca† eine content of green tea leaf, black tea quality parameters of theaÑavins, thearubigins, liquor brightness and total colour varied more among clones than with time of the year. In green ... -
The relationship between some chemical parameters and sensory evaluations for plain black tea (Camellia sinensis) produced in Kenya and comparison with simila...
(Elsevier, 2006-08-31)Reliable and accurately measurable chemical parameters that can be used to estimate black tea quality are desirable in trade, research and breeding programmes. Using plain Kenyan black tea from 11 cultivars, which gave ... -
Enhanced degradation of 14 C-HCB in two tropical clay soils using multiple anaerobic–aerobic cycles
(2013-02-28)The aim of the study was to induce and enhance the degradation of hexachlorobenzene (HCB), a highly-chlorinated persistent organic pollutant, in two ecologically different tropical soils: a paddy soil (PS) and a non-paddy ...
