Journal Publications – 2014

Authors: Ochanda, Simon Oduor, Onyango Christine Akoth, Mwanjala Alfred
Mwasaru, Ochieng Joy Kagwiria, and Mathooko Francis Mutiso
Title of Publication: Effects of malting and fermentation treatments on group B-vitamins of  red sorghum, white sorghum and pearl millets in Kenya
Abstract:

Objectives: To enhance the safety and nutritive values and shelf life of
sorghums and millet flours through malting and fermentation.
Methodology and results: Malting and fermentation were carried out for a
period of seven days with the aim of determining the optimal number of days
needed for each of these processing treatments. The quantities of folic acid,
niacin, thiamin, pyridoxine and riboflavin (B-vitamins) were then determined
by the reversed phase HPLC method described by Ekinci and Kadakal
(2005), modified from Cho et al., (2000) on each successive day of malting
and fermentation. Optimum results as determined on the basis of highest
increments in the contents of B-vitamins were obtained after malting for 3
days and fermentation for 2 days, at 25°C. Acidity and pH were also altered
by these processing techniques leading to improvement of flavour and
aroma shown by preliminary sensory evaluation results. Conclusion and
application of findings: Availability of all the selected B-vitamins was
significantly enhanced by fermentation by between 71.2 – 94.2%. On the
other hand only riboflavin was significantly affected by malting with 44.2%
increase, the rest increased by less than 10.5%. The results of this study will
be useful for the development of new products from neglected indigenous
cereals like sorghum and millet. This will enable value chain development for
the benefit of the community through realization of high nutrient foods and
better incomes from crops that do well in adverse climatic conditionsJournal: Journal of Applied Biosciences 34: 2128 – 2134 (2010)

Authors: Ochanda S.O, Onyango C.A ,Mwasaru M.A, Ochieng’ J. K, and Mathooko,
F.M
Title of Publication: Effects of alkali treatment on tannins and phytates in red sorghum, white sorghum and pearl millet
Abstract: Objective: Tannins and phytates anti-nutrients are abundant in sorghum and
millet; they reduce the nutrient value and organoleptic properties of foods.
Alkali treatment was therefore employed to detoxify them.
Methodology and results: Grain samples were sourced from the selected site
(Nguni, Ukambani Kenya). Preliminary physical and chemical analysis were
carried out to determine the indicators of ant-nutrients (colour and presence
of testa) followed by actual levels of anti-nutrients (quantities of tannins and
phytates) and the suitability of the grains for use in other treatments like
germination which are normally employed in the utilization of the cereals
(Shull et al., 1987). Following the physical and chemical analysis, alkali
treatment was done to reduce the levels of the anti-nutrients and the most
effective alkali identified. The quantities of the alkali application was based
on a concentration that retained germinability of the grains, had no negative
effect on consumer acceptability and had acceptable residual values of any
potentially harmful chemical on the grains. Four alkalis were used including
ash from pigeon pea pods, magadi soda, ammonia and sodium bicarbonate.
The cereals were steeped in the alkali solutions of varying concentrations
from 0-10% at varying time periods of between 0-7days. The reduction in
tannins and phytates were analyzed. The overall best alkali was magadi
soda applied at 1% for 2 days of steeping, this reduced tannins and phytates
by 68-75% and 14-29%, respectively. The grains had acceptable
organoleptic properties, over 91% germinability and the residual value of
sodium from the magadi soda was 98.09 mg/100g which was acceptable
(Shull et al., 1987; Makokha et al., 2002). Conclusion and application of
results: The different alkalis proved effective in the detoxification of tannins
and phytates, each of them reducing statistically significant amounts of the
anti-nutrients (pA0.05). The most effective of them was magadi soda,
followed by ash, ammonia and sodium bicarbonate. This information is
useful to the communities using these cereals since they can use locally
available compounds like magadi soda and ash from the legumes they use
to remove the anti-nutrients associated with the cereals thus improving their
quality and nutritive value. If the alkalis are used in the right quantities as
shown in this study, germinability of the grains and organoleptic properties
can still be retained. Therefore alkali treatment can be used in combination
with other processing techniques like malting and even fermentation to add
value to sorghum and millet.
Journal: Journal of Applied Biosciences 36: 2409 – 2418 (2010)

Authors: Mugendi, J. B. W., Njagi, E. N. M., 1Kuria, E. N., Mwasaru, M. A., Mureithi,
J. G. and Apostolides, Z.
Title of Publication: Nutritional quality and physicochemical properties of Mucuna bean (Mucuna pruriens L.) protein isolates
Abstract: The potential for mucuna bean protein isolate (MBPI) application as
functional ingredient in foods is unknown. In this study nutritional quality and
physicochemical properties of MBPI were investigated. Bean samples were
processed for L-dopa extraction in distilled water adjusted to pH 3.2 at 60°C
for 48hr. MBPI was extracted at pH 9.0 and isoelectrically precipitated at pH
4.5. MBPI from raw and processed seed contained higher protein content
(86.7 and 86.9% respectively) than soybean protein isolate (82.7%).
Essential amino acids content of MBPI met FAO/WHO scoring pattern for 2-
5 year-old. SDS-PAGE revealed four main polypeptide protein subunits of
apparent MW of 11, 19, 36 and 98 kD in MBPI. MBPI exhibited high foam
stability, emulsion activity and stability compared to soybean protein isolate.
However, poor foam expansion, water and oil absorption capacity and dark
colour (Hunter lab “L” value of 36.39) limits its potential as a functional food
ingredient.
Journal: International Food Research Journal 17: 357-366 (2010)

Authors: Mugendi JB, Njagi ENM, Kuria EN, Mwasaru MA, Mureithi JG and Z
Apostolides
Title of Publication: Effects of processing methods on the protein quality of mucuna bean (Mucuna pruriens L.)
Abstract: Mucuna bean (Mucuna pruriens L.) is grown in many parts of Kenya as a
green manure/cover crop. The bean contains a high content of crude protein.
However, it remains a minor food crop due to the presence of anti-nutritional
compounds such as 3,4-dihydroxy-L-phenylalanine (L-Dopa). The potential
for utilization of mucuna bean as an alternative source of protein was
evaluated by assessing the effect of various processing methods on its
protein quality. Mucuna bean was processed to remove L-Dopa and other
anti-nutritional compounds by different methods such as soaking,
autoclaving, roasting, germination, and alkaline fermentation. Protein quality
was determined by amino acid composition, in vitro and in vivo rat balance
methodologies. All processing methods except roasting improved in vitro
protein digestibility (IVPD). Soaking in acidic medium (pH 3.2) at 60°C for 48
hrs significantly improved IVPD (80.5%) and biological value (80.8) of
mucuna bean protein. The content of essential amino acids met the
recommended FAO/WHO reference requirements for 2-5 yr old except for
tryptophan. However, true digestibility for processed bean diet was poor
(58%) and protein digestibility corrected amino acid score (PDCAAS) low
(0.4) compared to that of reference casein (1.0). This was attributed to both
low sulphur amino acids content and possible presence of factors that affect
protein hydrolysis such as phenolic compounds. Mucuna protein diet did not
support growth of weanling rats indicating amino acids pattern incompatible
with the needs of weanling rats. Histological examination of liver and kidney
tissues revealed that consumption of processed mucuna bean as the only
source of protein caused inflammation of the organs. This suggests possible
presence of other antitoxins in processed bean even though mucuna bean
diet contained the recommended safe level of residual L-Dopa (<0.1%).
Processing mucuna bean by soaking in acidic medium (pH 3.2) at 60°C for
48 hrs improved protein quality. However, mucuna bean is not
recommended as a sole protein in human diet.
Journal: AJFAND ONLINE 10(4):2394-2412 (2010)

Authors: J. B. Mugendi, E. N. M. Njagi, E. N. Kuria, M. A. Mwasaru, J. G. Mureithi
and Z. Apostolides
Title: Effects of processing technique on the nutritional composition and antinutrient content of mucuna bean (Mucuna pruriens L.)
Abstract: Mucuna bean (Mucuna pruriens) is an indigenous legume promoted in
Kenya as a green manure cover crop. It contains high protein but it is under –
utilized due to the presence of 3, 4-dihydroxy-Lphenylalanine (L-Dopa) and
other anti nutritional compounds. To improve its nutritional potential as a
protein source, mucuna bean was processed and evaluated for nutritional
composition. Effects of processing at different pH, temperature and particle
size, autoclaving, germination and fermentation on the contents of antinutritional
compounds and crude protein were investigated. Raw beans
contained high crude protein (27.9 g/100-1). Contents of ether extract; crude
fibre and ash were 3.7, 7.9 and 3.5 g/100-1, respectively. Mineral content
was comparable to that of common pulses. Raw whole mucuna bean
contained high L-Dopa (7.0 g/100-1) content. Other anti-nutritional
compounds included total phenols 7.1 g/100-1, trypsin inhibitor activity (TIA)
5.1 TIU and phytates 0.9 g/100-1. All processing techniques, except
roasting, reduced levels of L-dopa by > 95% while less than 15% of protein
was lost. Soaking dehulled bean in acidic medium (pH 3.2) at 60°C for 48 h
reduced L-Dopa content to the recommended safe level of 0.1%. Processing
mucuna bean increased its nutritional value and potential to improve food
security
Journal: African Journal of Food Science 4(4): 156 – 166 ( 2010)

Authors: Onyango Christine Akoth, Ochanda, Simon Oduor, Mwasaru Mwanjala
Alfred, Ochieng Joy Kagwiria , and Mathooko Francis Mutiso
Title: Development of instant breakfast cereals from optimized flours of pearl millet, red and white sorghum
Abstract:

Objective: This was to develop instant breakfast cereals from optimized
flours of red and white sorghum and pearl millet.
Methodology and results: Breakfast cereals were developed from optimally
treated flours of red sorghum, white sorghum and pearl millet. Legume
complementation was done using pigeon peas. Other ingredients included
pigeon peas, wheat, sugar, salt, water and fat. Control products contained
the same ingredients but with untreated flours and without the pigeon peas.
The most preferred breakfast cereal was determined through sensory
evaluation. A comparison of the most preferred product with two breakfast
cereals in the market and shelf life analysis was also done. Conclusion and
application: The developed breakfast cereals from optimized fours of
sorghum and millet were generally acceptable to the consumer with their
nutritive values being as high as that of similar products in the market. This
technology can be adopted, further refined and up scaled to be used by
interested entrepreneurs to process sorghum and millet based breakfast
cereals for commercial purposes. In this way these orphaned crops can be
revived and the technologies developed to detoxify the antinutrients
associated with them adopted in their utilization.
Journal: Journal of Applied Biosciences 51: 3559– 3566 (2012)

Authors Mburu, M.W., Gikonyo, N.K., Kenji, G.M. and Mwasaru, M.A.
Title: Nutritional and functional properties of a complementary food based on Kenyan amaranth grain (Amaranthus cruentus)
Abstract:

The objective of this study was to determine the nutritional and functional
properties of Amaranthus cruentus grain grown in Kenya for preparation of a
ready-to-eat product that can be recommended as infant complementary
food. Amaranth grains were subjected to steeping and steam pregelatinization
to produce a ready-to-eat nutritious product with improved
solubility during reconstitution. The effect of processing on the functional and
nutritional properties of amaranth grain was analyzed. Two blends were
prepared from raw and processed amaranth grains. Standard procedures of
Association of Official Analytical Chemists (AOAC) were used to determine
the proximate chemical composition. High Performance Liquid
Chromatography (HPLC) was used quantify amino acid, water soluble
vitamins, α- tocopherols and phytates, while Atomic Absorption Flame
Emission spectrophotometry was used to determine the mineral element
composition. Fatty acid composition was determined using Gas Liquid
Chromatography (GLC). Tannin composition was determined using vanillin
hydrochloric acid method. The overall results indicated that processing
amaranth grain did not significantly affect its nutritional and physicochemical
properties. Amaranth grain product was rich in protein with 0.5 g/10g of
lysine, a limiting amino acid in cereals, and methionine, a limiting amino acid
in pulses. The product had good amount 44.4 mg/100g of α- tocopherols
important for infant development. The product was also rich in oleic acid
(36.3%) and linoleic acid (35.9%) with some amounts of linolenic acid (3.4%)
that are important for infant growth. It also had good amounts of minerals of
importance such as potassium (324.4 mg/100g), phosphorous (322.8
mg/100g), calcium 189.1 (mg/100g), magnesium (219.5 mg/100g), iron (13.0
mg/100g) and zinc (4.8 mg/100g). Considering amaranth grain product fed to
infant three times a day, at a reconstitution of 15% product, the levels of
magnesium, manganese and tocopherols were far above the recommended
intakes, while protein, phosphorous, iron, zinc, riboflavin and niacin were
above the average requirements. Therefore, reconstituting the product with
milk would enrich the deficient nutrients, especially for iron and zinc which
are crucial nutrients for infants. The processing method is a practical
approach aimed at combating the problem of malnutrition among infants and
young children in Kenya and other developing countries. The product
developed in this study would also be appropriate for use in geriatrics care
and also in immuno-compromised individuals. The technique in this study
can be easily adopted at both household and village levels to produce high
protein-energy weaning food to help enhance the nutritional status of
Kenyans.
Journal: AJFAND-ONLINE 12(2):5959-5977 (2012)

Authors: M.A. Ayieko, J.N. Kinyuru, M.F. Ndong’a and G.M. Kenji
Title of Publication Nutritional Value and Consumption of Black Ants (Carebara vidua Smith) from the Lake Victoria Region in Kenya
Abstract The edible insects of the Lake Victoria region which provided food and medicine, have suffered the effects of mismanaged environment. Our case study of Carebara vidua Smith (black ant) which is an endangered insect currently threatened with extinction due to human’s activities, have provided unique source of protein and medicinal value. C. vidua is an endangered species of Heminoptera. This paper discusses the nutritional value and medicinal potential of the black ant. It is one of the most sought after edible insects because of its nutritional and medicinal value. The samples were collected from Kisumu and Siaya counties along the Lake Victoria region. Standard nutrient analysis methods were used to determine the nutritional value.The insect has between 39.79 to 44.64% protein and about 42.07 to 49.77% fat content depending on the body part. The insect is also rich in iron, zinc, magnesium, potassium and phosphorus. From the fatty acid profile,the edible insects recorded high content of Palmitic, Oleic and Linoleic acids. No Linolenic acid was
found in the samples analysed. The elderly Luos of Kenya collect and consume the black ants to manage several body ailments probably due to the essential nutrients found in the insect. C. vidua Smith is fairly similar to Polyrhachis vicina Roger in China which has been processed and commercialised as medicinal to manage several chronic diseases. Further research is needed to highlight the potential medicinal value of C. vidua Smith in Kenya and to save the insect from total disappearance.
Name of Journal Advance Journal of Food Science and Technology
Year of Publication 4(1): 39-45, 2012

Authors: Mburu MW, Gikonyo NK, Kenji GM and AM Mwasaru
Title of Publication NUTRITIONAL AND FUNCTIONAL PROPERTIES OF A COMPLEMENTARY FOOD BASED ON KENYAN AMARANTH GRAIN (AMARANTHUS CRUENTUS)
Abstract

The objective of this study was to determine the nutritional and functional properties of Amaranthus cruentus grain grown in Kenya for preparation of a ready-to-eat product that can be recommended as infant complementary food. Amaranth grains were subjected to steeping and steam pre-gelatinization to produce a ready-to-eat nutritious product with improved solubility during reconstitution. The effect of processing on the functional and nutritional properties of amaranth grain was analyzed. Two blends were prepared from raw and processed amaranth grains. Standard procedures of Association of Official Analytical Chemists (AOAC) were used to determine the proximate chemical composition.
High Performance Liquid Chromatography (HPLC) was used quantify amino acid, water soluble vitamins, α- tocopherols and phytates, while Atomic Absorption Flame Emission spectrophotometry was used to determine the mineral element composition. Fatty acid composition was determined using Gas Liquid Chromatography (GLC). Tannin composition was determined using vanillin hydrochloric acid method. The overall results indicated that processing amaranth grain did not significantly affect its nutritional and physicochemical properties. Amaranth grain product was rich in protein with 0.5 g/10g of lysine, a limiting amino acid in cereals, and methionine, a limiting amino acid in pulses. The product had good amount 44.4 mg/100g of α- tocopherols important for infant development. The product was also rich in oleic acid (36.3%) and linoleic acid (35.9%) with some amounts of linolenic acid (3.4%) that are important for infant growth. It also had good amounts of
minerals of importance such as potassium (324.4 mg/100g), phosphorous (322.8 mg/100g), calcium 189.1 (mg/100g), magnesium (219.5 mg/100g), iron (13.0 mg/100g) and zinc (4.8 mg/100g). Considering amaranth grain product fed to infant three times a day, at a reconstitution of 15% product, the levels of magnesium, manganese and tocopherols were far above the recommended intakes, while protein, phosphorous, iron, zinc, riboflavin and niacin were above the average requirements. Therefore, reconstituting the product with milk would enrich the deficient nutrients, especially for iron and zinc which are crucial nutrients for infants. The processing method is a practical approach aimed at combating the problem of malnutrition among infants and young children in Kenya and other developing countries. The product developed in this study would also be appropriate for use in geriatrics care and also in immuno-compromised individuals. The technique in this study can be easily adopted at both household and village levels to produce high protein-energy weaning food to help enhance the nutritional status of Kenyans.
Name of Journal AJFAND
Year of Publication Vol.12 N02. April 2012

Authors: Silvenus O. Konyole, John N. Kinyuru, Bethwell O. Owuor, Glaston M. Kenji, Christine A. Onyango, Benson B. Estambale1, Henrik Friis, Nanna Roos & Victor O. Owino
Title of Publication Acceptability of Amaranth Grain-based Nutritious Complementary Foods with Dagaa Fish (Rastrineobola argentea) and Edible Termites (Macrotermes subhylanus) Compared to Corn Soy Blend Plus among Young Children/Mothers Dyads in Western Kenya
Abstract

We assessed acceptability of two flours and porridges of complementary foods based on
germinated grain amaranth and maize with or without edible termites and dagaa small fish named “Winfood Classic” (WFC) and “Winfood Lite” (WFL), respectively, compared to Corn Soy Blend Plus (CSB+) among mothers and young children. A total of 57 children consumed each of the three foods on separate days with one-day washout between foods. Each food was considered acceptable if the child consumed at least 75% of the serving. Most mothers preferred WFL flour and porridge (63.2% and 70.2%, respectively)
compared to WFC (24.4% and 10.5%) and CSB+ (12.3% and 19.3%). Children consuming at least 75% of served porridge were 43%, 19.6% and 21% for WFL, WFC and CSB+, respectively. No adverse effects were observed for all the foods throughout the study period and follow up lasting 4 weeks. All foods were acceptable and can be further developed and be tested for efficacy
Name of Journal Journal of Food Research;
Year of Publication Vol. 1, No. 3; 2012

Authors: John N. Kinyuru, Silvenus O. Konyole, Glaston M. Kenji & Christine A. Onyango, Victor O. Owino Bethwell O. Owuor
Tittle of Publication Identification of Traditional Foods with Public Health Potential for Complementary Feeding in Western Kenya
Abstract

The diversity of traditional foods in Kisumu West District of Western Kenya was assessed with an aim to identify the foods with a potential for complementary feeding. Leaves were the most consumed plant part amongst vegetables, while a few fruits were consumed together with their seeds. Amaranthus cruentus L. was found to be consumed as a leafy vegetable while another variety, Amaranthus hybridus L. was found to be consumed as a grain. Four species of winged termites, a grasshopper, black ant and dagaa fish were also identified. Twelve of the traditional foods were found to be associated with nutritional and health benefits as perceived by the locals. Traditional food processing methods such as boiling, fermentation and sun drying were identified. Thus exploitation of the species possessing nutrient, health and processing benefits needs to be explored in complementary feeding.

Name of Journal Journal of Food Research
Year of Publication Vol. 1, No. 2; May 2012

Authors: Glaston Mwangi Kenji and Richard Wanzala Wamalwa
Title of Publication Improvement of testing laboratories competency for economic and social growth
Abstract

Consumers everywhere expect consistent provision of quality products that they purchase. They need constant assurance that products procured exhibit little or no variation and are safe for use. These expectations can be satisfied when there is conformity, especially in measurements made during the manufacturing processes. To ensure this conformity, the testing laboratories must provide accurate analytical results, manned by well trained staff with well calibrated equipment so as to be able to reduce costs due to reduce wastage and health risks. Laboratory accreditation and profiency testing (PT) yield correct results that enable better technical and socio-economic decisions to be made and thus enhance efficiency of our businesses. We have about 300 testing laboratories in Kenya out of which only less than 10 are accredited. The accredited laboratories are required to periodically participate in PT. In the Second Round EAC PT in 2007, 25 and 33 laboratories in EA region paticipated in chemical composition for drinking water and wheat flour PT respectively. The z-scores were used as a basis for proficiency assessment for analytes for each respective determinands. The result from the participating laboratories in the wheat flour PT was: 53% produced satisfactory results; 28% did not produce reliable results with 9% as questionable results and 19% as unsatisfactory results; 19% did not submit the results of their tests. The results for chemical composition for drinking water PT was: 60%  produced satisfactory results; 24% did not produce reliable results; 16% did not submit the results of their tests. These inconsistent results from different laboratories after analysing the same sample demonstrate that the quality of data obtained from some of our laboratory is questionable. This paper therefore proposes that our testing laboratories should aggressively seek to be competent by getting accreditation by recognized accrediting bodies.

Name of Journal International Journal of Arts and Commerce 2012
Year of Publication Vol. 1 No. 4 September 2012

Authors: Kathurima C. W., Kenji G. M. Muhoho S. M. Boulanger R. Gichimu B. M.
and Gichuru E. K.
Title of Publication Genetic diversity among commercial coffee varieties, advanced selections and museum collections using molecular markers
Abstract

Molecular markers have effectively been applied to study genetic diversity and as markers of particular traits. This study assessed the diversity of twenty four (24) coffee genotypes using Random Amplified Polymorphic DNA (RAPD) primers and 2 microsatellites (M24 and Sat 235). A total of 35 polymorphic bands were generated by the RAPD primers. The bands were scored for presence (1) and absence (0) of amplified products. The data was subjected to cluster analysis using R statistical software and a dendrogram constructed using Unweighted Pair Group Method with Arithmetic Average (UPGMA). The genotypes separated into three main clusters. C. eugenioides clustered alone in the first cluster while un-introgressed Arabica genotypes dominated the second cluster. The third cluster comprised of Coffea canephora (Robusta) and introgressed genotypes, Ruiru 11, Hibrido de Timor and Catimor. Robusta and C. eugenioides were the most distantly related and generated most of the diversity observed. The similarities observed among un-introgressed Arabica genotypes attest to the narrow genetic diversity within Coffea arabica. The divergence observed among introgressed genotypes could be utilized in future breeding programmes.
Name of Journal International Journal of Biodiversity and Conservation
Year of Publication Vol. 4(2), pp. 39-46, February 2012

Authors: Mbae KM, Kiiyukia C and GM Kenji
Title of Publication IN VITRO PRODUCTION OF TRICHOTHECENES AND ZEARALENONE BY FUSARIUM ISOLATES FROM EQUATORIAL BARLEY
(HORDEUM VULGARE L.) GROWN IN KENYA
Abstract

Fusarium head blight (scab) is a devastating disease of wheat and barley throughout the world. The disease has been reported worldwide wherever cereals are grown, cutting across diverse ecological and geographical distribution. In addition to being pathogenic to plants, which may cause severe crop yield reduction, many Fusarium species are also capable of producing mycotoxins deleterious to human health as secondary metabolites. Fusarium toxins are commonly detected in wheat, barley, maize, rice and beer. Traditionally malted barley (Hordeum vulgare L.) is the principal ingredient in
clear beer and Fusarium toxins incidences are of major concern. Moreover, the spent grain from the brewing industry is used as feed and presence of mycotoxins can lead to harmful effects on domestic animals and also find a way into the human food chain. Studies carried out in Kenya have revealed presence of various Fusarium species with ability to produce mycotoxins and presence of Fusarium toxins in wheat and maize and beer. Based on the ubiquitous nature of Fusarium mold and the fact that barley production takes place in maize and wheat growing areas, this study set out to investigate the occurrence of Fusarium molds in Equatorial barley grown in Kenya and the ability of the isolates to
produce selected mycotoxins. Grain samples were obtained from newly delivered barley lots originating from two regions and stored grain awaiting malting after break of dormancy from Kenya Maltings Ltd., Nairobi. The Fusarium isolates were identified to species level based on cultural and morphological characteristics. Additionally, they were screened in-vitro on rice cultures for their ability to produce Type A trichothecenes (T–2 toxin, HT–2 toxin, Diacetoxyscirpenol), Type B trichothecenes (deoxynivalenol and nivalenol) and Zearalenone. Samples from all sources were contaminated with Fusarium, but at varying magnitudes – 50%, 33.3% and 25% for barley kernels originating from Timau, Olchoro and in-storage grain with no common history of origin, respectively. The distribution of the species showed some regional specificity. F. graminearum and F. poae predominated in kernels sourced from Olchoro region. All strains of F. graminearum produced both deoxynivalenol and zearalenone. F. poae strains and F. chlamydosporum did not produce detectable amounts of the screened mycotoxins. However, two inconclusively identified isolates of Fusarium spp. isolated from Timau samples produced deoxynivalenol only. The study revealed that a number of toxigenic Fusarium spp. do occur in Equatorial barley grown in Kenya.
Name of Journal AJFAND
Year of Publication Vol. 12 No. 5 2012

Title: Characterization of pMRI 5.2, a rolling-circle-type plasmid from Lactobacillus plantarum BFE 5092 which harbours two different replication initiation genes
Authors: Gyu-Sung Cho; Melanie Huch; Julius Maina Mathara; Marco J. van Belkum;
Charles M.A.P. Franz.
Plasmid 69 (2013) 160–171
Year 2013:
Abstract
Plasmid pMRI 5.2 from Lactobacillus plantarum BFE 5092 was sequenced and
analysed. The sequence consists of 5206 bp with a mol% G+C content of 35.8%. Nine
putative open reading frames were identified. A typical pC194 family double strand
origin (dso) and a putative single strand origin (sso) were predicted upstream of a rep
gene. This rep gene encoded a replication protein of 314 amino acids exhibiting 98%
amino acid sequence identity to the Rep protein of plasmid pLAB1000 from
Lactobacillus hilgardii. A mob gene encoding a mobilization protein was also identified
and this protein showed high amino acid similarity to Mob proteins from various
Lactobacillus plantarum plasmids. Downstream of the mob gene, a second putative
replication region was identified that is similar to the pMV158 family of plasmids. It
contains a dso as well as a putative sso, and encodes the 52 amino acid repressor-like
protein RepA, the replication initiation protein RepB of 215 amino acids, and the 48
amino acid RepC that is similar to ORFD of the lactococcal plasmid pWVO1. RT-PCR
and qRT-PCR expression analyses of the rep and repB genes showed that the repB gene
was expressed at a higher level. To confirm that the plasmid replicated by the rollingcircle-
type mechanism, the presence of a characteristic single strand intermediate DNA
was shown to be produced during replication. Plasmid copy number was ca. 30 per
equivalent chromosome copy number based on qRT-PCR analyses. The plasmid also
encodes four additional putative proteins of unknown function. The unusual feature of a
rolling-circle plasmid having two different plasmid-encoded replication initiation
proteins from different replicon families suggests that the genes for these may have
originated from different plasmids.

Title: Fusarium langsethiae – a HT-2 and T-2 Toxins Producer that Needs More Attention
Authors: Samuel M. Imathiu, Simon G. Edwards, Rumiana V. Ray and Matthew A.
Back
Abstract:
Fusarium langsethiae is a toxigenic fungus that was formally described as a new species
in 2004. This fungus was first detailed in the 1990s but was initially referred to as
‘powdery Fusarium poae’ having a spore morphology similar to F. poae but a
mycotoxin profile like that of Fusarium sporotrichioides. The species has been isolated
from infected oat, wheat and barley grains but has been reported as more problematic in
the former crop rather than the latter two. Whilst the epidemiology of F. langsethiae
remains unclear, the fungus has been shown to produce high levels of type- A
trichothecenes HT-2 and T-2 toxins in small-grain cereals. HT-2 and T-2 toxins are two
of the most potent trichothecenes capable of inhibiting protein synthesis in eukaryotes. In
this regard, mycotoxin contamination caused by F. langsethiae is clearly a food and feed
safety hazard. With the European Commission considering legislation of HT-2 and T-2
toxins, more information is required not only on the producer and conditions favouring
mycotoxin production, but also on reliable methods of pathogen detection and reduction
of cereal contamination. This review describes recent research concerning the known
epidemiology of F. langsethiae and suggestions of what needs to be known about the
fungus in order to be able to understand and employ measures for preventing its
infection and contamination of cereals with HT-2 and T-2 toxins.
13
Journal: Journal of Phytopathology Vol 161, pp 1-10
Year: 2013

Title: Molecular studies to identify the Fusarium species responsible for HT-2 and T-2
mycotoxins in UK oats
Authors: Simon G. Edwards , Samuel M. Imathiu , Rumiana V. Ray , Matthew
Back, Martin C. Hare
Abstract: High levels of Fusarium mycotoxins HT-2 and T-2 have been detected
in UK oats since surveys started in 2002. Fusarium langsethiae and the closely related
species F. sporotrichioides have previously been associated with the contamination of
cereals with type A trichothecenes HT-2 and T-2 in Nordic countries. Preliminary
microbiological analysis of UK oat samples with high concentrations of HT-2 and T-2
detected and isolated F. langsethiae and F. poae but not the other type A trichothecene
producing species F. sporotrichioides, F. sibiricum and F. armeniacum. Two hundred
and forty oat flour samples with a known mycotoxin profile were selected from a
previous four year study (2002–2005) to cover the full concentration range from below
the limit of quantification (˂20 μg/kg) to 9990 μg/kg HT-2+T-2 combined. All samples
were analysed for the DNA of F. langsethiae, F. poae and F. sporotrichioides based on
previously published PCR assays. F. langsethiae was detectable in nearly all samples; F.
poae was detected in 90% of samples whereas F. sporotrichioides was not detected in
any sample. A real-time PCR assay was developed to quantify F. langsethiae DNA in
plant material. The assay could quantify as low as 10−4 ng F. langsethiae DNA/μl.
Based on this assay and a previously published assay for F. poae, both species were
quantified in the oat flour samples with known HT-2+T-2 content. Results showed a
good regression (P˂0.001, r2=0.60) between F. langsethiae DNA and HT-2+T 2
concentration. F. poae DNA concentration was not correlated to HT2+T2 concentration
(P=0.448) but was weakly correlated to nivalenol concentration (P˂0.001, r2=0.09).
Multiple regression with F. langsethiae and F. poae DNA as explanatory variates
identified that both F. langsethiae and F. poae DNA were highly significant (P˂0.001)
but F. poae DNA only accounted for an additional 4% of the variance and the estimate
was negative, indicating that higher concentrations of F. poae DNA were correlated with
slightly lower concentrations of HT2+T2 detected. A stronger regression (P˂0.001,
r2=0.77) between F. langsethiae DNA and HT-2+T-2 was obtained after extraction and
quantification of DNA and mycotoxins from individual oat grains. The results from this
study provide strong evidence that F. langsethiae is the primary, if not sole, fungus
responsible for high HT-2 and T-2 in UK oats.
Journal: International Journal of Food Microbilogy Vol. 156, pp. 168-175
Year: 2012

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