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FORMS AND BIOAVAILABILITY OF ZINC AND COPPER ESSENTIAL ELEMENTS IN PARTS OF WATERMELONS FROM NGARA AND MWEA MARKETS, KENYA
(2018-09) Bernard Chege
During the last few decades analytical chemists and nutrition scientists have
increasingly realized that total concentrations of chemical elements cannot give, in
general, information about mobility, bioavailability, and the eventual impact of
elements on biological organisms. Only the knowledge of the chemical species of the
elements can provide an understanding of chemical and biochemical reactions,
bioavailability, and subsequent paths of metabolism, thus leading to more information
about essentiality or toxicity. This stresses the necessity of speciation analysis to
determine the species of an element in a specific matrix. There is need therefore to
determine the species of essential elements in different types of fruits, vegetables and
other foods. One fruit that is increasingly being consumed and which is available
throughout the year and has essential elements is watermelon (Citrullus lanatus
(Thunb.) Matsum and Nakai). There is need to determine the form in which the
essential elements occur in the seed, red flesh, white flesh and peel in a watermelon to
avoid deficiency when used as food to encourage use of thrown away parts. The study
therefore aimed at providing information on bioavailability and forms of essential
elements in the peel, white flesh, red flesh and seed parts of watermelons. Water and
ethanol extractable elements are more available for absorption than those extracted by
other solvents. Watermelons selected for the study are widely consumed and were
purchased from Mwea and Ngara markets in Kenya. They were separated to peel,
seed, white and red flesh and dried. Each of the watermelon part was sequentially
extracted with hexane, dichloromethane, ethanol, water and lastly residue digested
and Flame Atomic Absorption Spectrometry (FAAS) was used to determine the levels
of each element in various fractions. Free Zn2+ and Cu2+ ions and their organic acid
complexes in the extracts constitute the bioavailable forms. The data of this study
were analysed through One Way Analysis of Variance. The results of this study
showed that there were variations in extracted mean levels of Zn and Cu minerals in
the parts and varieties of watermelon. Significantly high water extracts mean levels (p
< 0.001) of 0.46±0.01 mg/100 g, (46%) Cu was recorded in peel of sugar baby from
Ngara market compared to the other watermelon samples. Crimson sweet watermelon
samples bought from Ngara market recorded the highest Zn water extracts mean
levels (p < 0.001) of 4.84±0.04 mg/100 g, (52%) in red flesh compared to the other
watermelon varieties in the market. Charleston grey watermelon samples from Mwea
market significantly recorded a high Zn water extracts mean levels (p < 0.001) of
5.96±0.01 mg/100 g, (61%) in white flesh than was recorded in the other parts of the
watermelon varieties. Presence of hexadecanoic and octadecanoic acids which are
complexing agents that enhance bioavailability of Zn and Cu were obtained in the
watermelon extracts through GC - MS analysis. The bioavailable species of Zn and
Cu could have been either as free ions or their organic acid complexes. Since Zn and
Cu minerals were bioavailable in the four parts of the watermelon samples, people
should eat all the parts of watermelon either when dry or fresh as a source of these
nutrients. Result from this study will be used to guide people on nutrition aspect of a
watermelon which will in turn enhance human health.
FISH PROTEIN HYDROLYSATE FROM DAGAA (Rastrineobola argentea) AS NUTRITIONAL COMPONENT IN MICROBIAL CULTURE MEDIA
(2016-09) Pere Katherine
Dagaa is a small pelagic fish found in Lake Victoria. It is mainly used as a nutrient
source in the animal feed industry as well as for human consumption among the
poor and the middle class. Fish protein hydrolysate as a source of nutrient in culture
media has been explored in several fish species such as Silver Carp, Yellow Tuna,
Yellow Stripe Trevally, Herring and Mackerel. Dagaa could also be an excellent
candidate for culture media since it is rich in proteins, lipids and minerals. This
would also add value to the underutilized fish species and minimize post-harvest
losses of up to 50% during rainy seasons. In the current study, Dagaa as a source of
nitrogen in culture media was explored by first preparing the Dagaa Protein
Hydrolysate (DPH) using Alcalase enzyme. Proximate analysis for protein, lipid,
moisture /dry weight and ash contents of DPH was performed and compared with
that of Dagaa, Dagaa Fish Hydrolysate (DFH), Standard media Luria Bertani (LB)
and Sabouraud’s Dextrose Broth (SDB). Mineral analysis was also performed on all
these samples. The potential of DPH as a nitrogen source in microbial growth media
was investigated using; Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis
and Rhodobacter capsulatus for bacterial growth studies while Metarhizium
anisopliae and Beauveria bassiana were used for fungal growth. Potential of DPH
to sustain production of commercial valued enzyme amylase was also investigated
with R. capsulatus and B. subtilis in DPH-Starch media. This was done using
Dinitrosalicylic (DNS) acid assay. M. anisopliae was analyzed for sporulation
(conidia production) rate in DPH-Dextrose media. Proximate and mineral analysis
indicated that there was significant difference (p<0.05) in the nutritional and mineral
profiles of DPH and the two standard media (LB and SD). The protein content of
DPH was higher than that of LB and SDB while the mineral content of DPH was
lower than that of LB but slightly higher than that of SDB. LB had more Sodium
content than DPH. Investigation of the potential of DPH as a nitrogen source in
media indicated that in all microorganisms used in this study, there was no
significant difference (p˃0.05) in DPH-FM and DPH-Dextrose as compared to
standard media in the growth of microorganisms. The potential for DPH-Starch to
sustain production of commercial valued amylase indicated that there was
significant difference (p<0.05) in the sustenance of amylase production in
formulated DPH-Starch and standard media by R. capsulatus and B. subtilis. DPHStarch media gave better production of amylase enzyme in both microbes than the
standard media. There was no significant difference (p˃0.05) in the sporulation rates
of M. anisopliae in DPH-Dextrose and the standard media. Hence DPH formulated
media can be substituted as a potential culture media for microbial growth. The cost
of formulation is low and provides an alternative means of value addition to Dagaa.
FINGERPRINTING AND RELATING JUVENILE CHARACTERS OF RICE TO YIELD AND YIELD COMPONENTS IN KIAMBU AND KIRINYAGA COUNTIES
(2019-02) SYLVIA A. HENGA
Rice is increasing as an important food and cash crop in Kenya and is third to maize and
wheat in terms of consumption. Consumption has continually outstripped production
resulting in massive importation. The main problem affecting productivity involves lack
of proper information on best storage time, use of poor quality seed, varietal admixtures
which has contributed to low yields. There is need to characterize genotypes.
Microsatellit are useful in various plant genetic studies and plant characrerization.
Accelerated aging is considered an excellent option as a vigor test due to shortest time of
acquisition and efficient results. In the proposed study, seed quality experiments
including germination, dormancy, purity, were carried out in the laboratory using eight
rice varieties in a Completely Randomized Design. Accelerated ageing tests at 0,24,48
and 72hrs(45oC and 98%RH) were carried out JKUAT post-harvest laboratory using
eight rice varieties‟ in four replications of100 seeds each. Data was collected on dates to
plumule and radical emergence and height. Five varieties were used to produce seeds
which were stored for 1,2,3,4,5 and 6 months respectively. The seedlings were
transplanted into fields in a Randomized Complete Block Design using 5*6 factorial
arrangement. The study also determined the relationship between juvenile characters and
adult characters of rice in Kiambu and Kirinyaga counties. All the data were analyzed
using GENSTAT statistical package. ANOVA and LSD at 5% significant level. Seed
quality results showed that There was significant variation in both coleorrhiza and
coleoptile formation among rice varieties (p<0.001), treatments (p<0.001) and interaction
between rice varieties and treatment ((p<0.001). The difference between all treatments
was significant with 72 hours treatment having the highest number of days to coleorhiza
and coleoptile formation. Results showed that the effect of genotype on coleorhiza and
colleoptille formation was significant (p<0.001). Genotype B317 had the earliest
colleoptile formation 8.75days, coleorhiza formation (9.81), B317 also had the highest
germination percentages at 7(33.69), 14 (52.44) and at 21 days after sowing (56.62).
Mzungu had the latest number of days to coleorhizae (12.44), coleoptiles (11.18) and
lowest germination percentages at 14(27.52) and 21days (31.31). The genotype had
significant effect on germination index, seed length and seedling vigor index. In Mwea,
there was a significant effect of storage time on germination, with 4 months giving the
highest seedling vigor index (673.6), height at 1 month after transplanting (73.3cm),
height at maturity (72.3cm) and 3 months giving the highest days to flowering(58.87)
.The interaction between storage time and genotype on was significant, with genotype
B217 stored for 3 months leading in height at one month after transplanting (87.7),
height at maturity(91.8cm) .in Kiambu.The interaction between storage time and
genotype was significant with 5months of storage having the highest seedling vigor index
(759.5), 1000grain weight (69) and yield (15.5kg/ha). Analysis of molecular variance
results indicated that the five polymorphic markers used in this study showed a total of 11
alleles across the loci of the 18 rice genotypes studied. Juvenile characters such as
seedling vigor and height at transplanting had a positive and significant correlation to
1000grain weight.Genotypes TXD and B217 were identified by the 5 markers. TXD
(Saro 5) was the best fit for fingerprinting as it was identified by only 1 marker. These
results could be used in preparing rice seed certification procedures, in gene bank
management and other seed storage ventures.
ELECTRON IMPACT ELASTIC SCATTERING OF STRONTIUM USING DISTORTED WAVE METHOD
(2018-11) KIMANI MARTIN KIRUGU
Differential and integral cross sections for electron-atom are useful for interpretation
and understanding of electron contact with the targets and for determining dynamics of
the collision processes. They are useful in X-ray photoelectron spectroscopy (XPS),
upper atmosphere dynamics, Monte-Carlo simulation (MCS), Auger-electron
spectroscopy (AES), in gaseous-exchange, laser development, plasma physics and
fluorescent lighting. For elastic scattering of strontium very few calculations have been
performed and currently there are no known results using the present method. Also the
available theoretical results do not have other results to be compared with so it makes it
important to obtain results to compare them and to be compared with future
experimental results. In calculation of differential and integral cross section for elastic
scattering of electron by strontium atom, first-order distorted wave born approximation
method has been used to determine DCS and ICS at impact energies of 10eV to 200eV
and scattering angles ranging from 00 to 1800
. Also in this study at the initial state, both
initial and final channel distortion potential of elastic scattering of electron by a
strontium atom are taken as the static potentials since it is an elastic scattering. The
distorted waves are expanded in terms of radial wavefunctions and spherical harmonics,
Numerov method was then used to solve the radial equations to obtain the radial
wavefunctions. The Madison and Bartschat computer program DWBA1 for e-
- H
scattering was modified to perform the mathematical computations for e -
- Sr scattering
and the results for differential and integral cross sections are calculated and compared
with the available results. The integral cross sections (ICS) results agree well
qualitatively with the other theoretical results. At lower incident energies (10-30 eV),
the present differential cross section (DCS) results disagree with results obtained from
optical potential method. This is because the first order distorted wave method gives
poor results at low impact energies and also the nature of the distortion potential used.
At intermediate and higher energies (60-200 eV), the present DCS results agree well
with the results obtained from optical potential method. In conclusion, the DWBA was
developed and applied to 𝑒− - Sr scattering, changes on the DWBA1 computer program
were made for strontium, differential cross section (DCS) and integral cross section
(ICS) at impact energies 10-200eV for elastic scattering of electron-strontium were
determined using DWBA at intermediate and high energies and the results compared
with the other available results. From this work it was recommended that some
experimental studies on electron impact elastic scattering of strontium should be made
to give results for comparison with the calculated results, more theoretical studies using
other methods should be conducted on DCS and ICS for purposes of comparison with
the present results, a distortion potential that incorporates the polarization potential,
exchange potential and absorption potential should be used in the calculation and the
present method incorporating all the distortion potentials should be extended further for
electron impact elastic scattering of other alkaline earth metals such as beryllium,
cesium, ytterbium, and radium.
EFFICACY OF PSYCHO-EDUCATIONAL NUTRITION INITIATIVE ON ENERGY AND MICRONUTRIENT INTAKE, PHYSICAL ACTIVITY AND PREGNANCY OUTCOMES IN MIGORI COUNTY, KENYA
(2019-03) ODIWUOR OYEHO FLORENCE A.
A large number of pregnant women in many parts of the world enter pregnancy at
sub-optimal weight and height. A third of Kenyan population suffer from food
insecurity that is further complicated by factors such as adverse weather conditions
and increases in food prices. The result is malnutrition which primarily affects
pregnant women and children under five years and significantly contributes to their
morbidity and mortality. Maternal nutrition is critical for both mother and child as it
lays fundamental foundation for the successful outcome of pregnancy. Kenya’s high
rate of undernutrition among women of reproductive age are due to sub-optimal
feeding practices, heavy workload, inadequate micronutrient intake and insufficient
awareness and knowledge on nutritionally adequate diets among pregnant women
leading to preterm births, low birth weight, high mortality and morbidity, impaired
growth, and increased risks during childbirth for both mother and child. This study
sought to investigate socio-demographic characteristics, determine nutrition
knowledge and health conditions and effect of nutrition educationon nutrition
knowledge and dietary practices, assess energy and micronutrient intake, determine
physical activity levels, and determine pregnancy outcomes and associations between
psycho-educational nutrition initiative and nutrient intake, physical activity and
pregnancy outcomes among pregnant women in Migori County. A prospective cohort
study design was used and simple random sampling was used to obtain a sample of
150 pregnant women from three sub-county hospitals purposively selected for study.
Pregnant women of GA ≤26 weeks were recruited and enrolled into psychoeducational nutrition intervention study. Data was collected by 24 hour recall,
International Physical Activity Questionnaire, biochemical analysis, anthropometric
measurements and secondary data. Data was collected at baseline and after
intervention for each woman and analyzed by Nutri-Survey computer package, IPAQ
scoring protocol and SPSS. Data was summarized by descriptives and relationships
between variables was tested by Chi square, regression model and pearson’s product
moment correlation.ANOVA and t-tests were used to test for differences between
means. Findings showed that the pregnant women were of low economic status.
Nutrition education had positive significant associations with nutrition knowledge and
practices. Most women had good health with on conditions interfering with their food
consumption. Generally, there was improved dietary intake of all nutrients after the
intervention although some did not meet the RDA even after intervention There was a
slight reduction in physical activity factors and increased time for rest was observed
after intervention although there was no significant reduction in activity levels (p ≤
0.05). Weight gain (5.98 kg) was lower than recommended, mean gestation age was
normal (37.74 weeks) but lower for preterm births category and mean BW
(3039±489.5 g) was normal although 7% of new bornes had LBW. The study found
significant effects of nutrition knowledge from the psycho-educational initiative on
nutrient intake and pregnancy outcomes but found no effect on physical activity. The
study concludes that nutrition education can be used to enhance pregnancy outcomes
and nutrient intake among pregnant women. The finding is important to central and
county governments, civil society, intergovernmental agencies, research groups,
business enterprises and community under study
