School of Biological and Physical Science: Recent submissions
Now showing items 901-920 of 933
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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 ... -
Immobilization of chlorobenzenes in soil using wheat straw biochar
(American Chemical Society, 2013-04-25)Biochar has shown great potential for immobilizing organic contaminants in soil. In this study, pentachlorobenzene (PeCB), 1, 2, 4, 5-tetrachlorobenzene (1, 2, 4, 5-TeCB), and 1, 2, 4-trichlorobenzene (1, 2, 4-TCB) ... -
Effects of pH and metal ions on oxytetracycline sorption to maize-straw-derived biochar
(Elsevier, 2013-05-30)Biochars produced from biomass residues have been recognized as effective sorbents to hydrophobic compounds, but knowledge on sorption of antibiotics to biochar and its mechanisms are still inadequate. Sorption of ... -
Isolation and characterization of a toxic metal-tolerant Phenanthrene-degrader Sphingobium sp. in a two-liquid-phase partitioning bioreactor (TPPB)
(2013-10-01)A phenanthrene-degrading strain PHE3, identified as the genus of Sphingobium, was isolated using a two-liquid-phase partitioning bioreactor. More than 96% of the initial amount (up to 100 mg l− 1 silicone oil) of ... -
Tenax extraction for exploring rate-limiting factors in methyl-β-cyclodextrin enhanced anaerobic biodegradation of PAHs under denitrifying conditions in a red paddy...
(Elsevier, 2014-01-15)The effectiveness of anaerobic bioremediation systems for PAH-contaminated soil may be constrained by low contaminants bioaccessibility due to limited aqueous solubility and lack of suitable electron acceptors. Information ... -
Remediation of organochlorine pesticides (OCPs) contaminated site by successive methyl-β-cyclodextrin (MCD) and sunflower oil enhanced soil washing–portulaca...
(Pergamon, 2014-06-30)An innovative ex situ soil washing technology was developed in this study to remediate organochlorine pesticides (OCPs)-contaminated site. Elevated temperature (50 C) combined with ultrasonication (35 kHz, 30 min) at ... -
Role of cosubstrate and bioaccessibility played in the enhanced anaerobic biodegradation of organochlorine pesticides (OCPs) in a paddy soil by nitrate and methyl...
(Springer Berlin Heidelberg, 2014-07-01)Abstract The present study was conducted to investigate the anaerobic biodegradation potential of biostimulation by nitrate (KNO 3) and methyl-β-cyclodextrin (MCD) addition on an aged organochlorine pesticide ... -
Evaluation of soil washing process with carboxymethyl-β-cyclodextrin and carboxymethyl chitosan for recovery of PAHs/heavy metals/fluorine from metallurgic plant...
(Elsevier, 2014-08-01)Abstract Polycyclic aromatic hydrocarbons (PAHs)/heavy metals/fluorine (F) mixed- contaminated sites caused by abandoned metallurgic plants are receiving wide attention. To address the associated environmental problems, ...