Charles Nkonge Presentation to the Excursion Meeting on “Networking on aflatoxin Reduction in food value Chain” held at KALRO HQ on 15/8/16

1. Kenya Agricultural & Livestock Research Organization (KALRO)
Overview of Aflatoxin Research Activities
in KENYA
Charles Nkonge
Presentation to the Excursion Meeting on “Networking on aflatoxin Reduction
in food value Chain” held at KALRO HQ on 15/8/16

2. Actors involved
Research and Regulatory
Institutions (KALRO,
KEMRI, KEBS, KEPHIS,
CPB)
Universities (UoN,
JKUAT, KU,
MMUST)
Ministries (MoAL&F,
MoH)
Development Partners
(US (USAID, USDA)
Germany (GIZ, BMZ),
Australia (DFAT),
Finland), World Bank,
FAO
International
NGOs
(ACDI/VOCA,
AATF)
CGIAR Centers
(ILRI, IFPRI, IITA)
KALRO
Aflatoxin research

3. Introduction
Most important molds in cereal crops, especially with respect to
maize spoilage and contamination with mycotoxins in Kenya belong
to three genera, Aspergillus, Fusarium and Penicillium.
Most research work has been done on mycotoxins produced by
Aspergillus and least on those produced by Penicillium
Several toxins are produced by Aspergillus species but aflatoxins
have attracted the highest attention.
The species in the Aspergillus genus that are commonly implicated in
maize aflatoxin contamination are A. flavus A. parasiticus, A. niger,
A. fumigitus.

4. Aflatoxin Contamination Predisposing factors
Environmental conditions especially high humidity and temperatures
favour fungal proliferation resulting in contamination of food and
feed. (Wagacha and Muthomi 2008)
Pre-harvest practices; time of harvesting; handling of produce during
harvesting; moisture levels at harvesting, transportation, marketing
and processing; insect damage all contribute to mycotoxin
contamination.
Sub optimal Agronomic practices, inadequate rain during growing
season, too much rain at harvest, poor storage conditions
Effect of stress caused by MLND on Aflatoxin?

5. Summary of Research Carried out

6. 1.Surveys, Mapping out Aflatoxin hot spots
1.1 Aflacontrol – ACDI/VOCA and KALRO
Prevalence of aflatoxins along the maize value chain in three areas in Kenya determined. Contamination
prevalent in both Western and Eastern Kenya but more in Eastern Kenya.
Contamination found to occur both pre- and post-harvest
Partners (IFPRI, CIMMYT, KARI, ICRISAT, University of Pittsburgh, United States Uniform Health Services)
1.2 UoN - CAVS (Muthomi et al )
Aflatoxin contamination of maize found to be more in Eastern Kenya as compared to North Rift. This was
attributed to climatic conditions of the two regions.
Aflastop- Storage technologies to reduce contamination

7. 2. Models to predict outbreaks (ILRI and others)
2.1 Good correlation between aflatoxin contamination and increased rainfall
at flowering and also increased contamination and decreased rainfall
through out the season was reported on Kenya maize by a team of
researchers from Cornell University.
2.2 A method for mapping of aflatoxin risk areas in the milk value chain in
Kenya using GIS approach was developed (ILRI, Sweedish University, UoN and
partners from Japan) .
2.3 A method using remotely sensed data was developed to predict aflatoxin
contamination in Eastern Kenya but the method could be developed further
to be applied elsewhere by a team from Cornell University
A

8. 3. Aflatoxins in maize value chains
Aflatoxins in Kenya which were first noted as early a 1960 and has since
persisted year after year (Steve Collins).
In 1961, about 16,000 turkeys died due to consumption of aflatoxin
contaminated groundnut feeds.
A country wide survey carried out in 2005 had found 21.7% of grains
sampled had Aflatoxins levels above 20 ppb.

9. 4. Feeds, Livestock/ dairy value chains
4.1 UoN and ILRI jointly or separately with others have done a lot of
studies on the prevalence of aflatoxins in feeds and milk value chains.
Contamination rate found to be high
4.2 In a survey of milk marketed through 4 types of small businesses in
peri-Nairobi gave results of 55% of samples that exceeded the
European Union maximum level of 0.05ppb. (ILRI)

10. 5. Biological reduction of aflatoxin
contamination of maize
5.1 Researchers in KALRO in collaboration with others (IITA, USDA-ARS, AATF,
ACDI-VOCA & NIB) are able to reduce the level of aflatoxin contamination by
between 70 and 99% through use of biological control
Maize fields are inoculated with Aflasafe KE01 a collection of about 3-4
atoxigenic bacterial 2-4 weeks before tasselling which out-compete the
native strains.
There is a carry of this effect to neighboring fields and following seasons.
A mycotoxin laboratory to serve East African countries is in operation and
currently serving 3 countries of Kenya, Uganda and Rwanda.
A modular plant to manufacture Aflasafe will has already been constructed
and will be equipped by next year.

11. 6. Aflatoxin Detoxification
6.1 Nixtamilzation
Led by KALRO with other collaborators (CIMMYT, MoAL&F, UoN and
Mexican Embassy).
The project will lead to reduction in aflatoxin levels in maize kernels
and improve the nutrition quality of maize by increasing the
bioavailability of niacin, calcium, iron and zinc.

12. 5. Aflatoxin Detoxification continued-----
5.2 Effect of dehulling maize
Researchers from UoN and KIRDI by using a traditional method of
dehulling maize were able to remove about 50% aflatoxin
5. 3 Effect of Lactic acid fermentation
Using monoculltures of Lactic Acid producing bacteria researchers from
Sokoine and Michigan universities were able to remove about 50%
aflatoxin B1 from fermented porridge. Wild fermentation with back-
slopping removed slightly more.

13. 6.
6.Control of aflatoxin accumulation at Molecular
level
6.1 Applying a strategy called host-induced gene silencing researchers
fron KU & JKUAT were able to transform maize targeting the aflatoxin
biosynthesis transcription factor aflR. The transgenic maize produced
14 fold less aflatoxin.
However the process led to undesirable effect of stunted maize and
reduced kernel placement which have to be overcome.

14. Way Forward
Quite a bit of work has been done in several research areas on aflatoxin
The following is what I think some of the gaps that need to be plugged
1. There is need to strengthen linkages between the different actors in the
aflatoxin research. This will lead to less duplication of efforts and increase
efficiency in use of available resources
2. Capacity building of 2 Kenyan scientists is planned in the AFLANET project. If it
is possible this should be accompanied by facilitation to build capacity of more
researchers by the 2 people trained in Germany.
3. Affordable rapid field test kits for aflatoxin testing of farmers maize is a priority
4. There is urgent need to develop alternative non-food commercial use of
contaminated grain to cut down on losses incurred.

15. SYNONYMNS Used
• AATF - African Agricultural Technology Foundation
• ACDI/VOCA - Agricultural Cooperative Development International/
Volunteers in Overseas Cooperative Assistance
• CAVS – College of Agriculture and Veterinary Services
• CGIAR - Consultative Group on International Agricultural Research
• CIMMYT – International Maize and Wheat Improvement Centre
• CPB – Kenya Cereals and Produce Board
• IFPRI - International Food Policy Research Institute
• IITA – International Institute of Tropical agriculture
• ILRI – International Livestock Research Institute
• JKUAT – Jomo Kenyatta University of Agriculture and Technology

16. SYNONYMNS Used continued---
• KALRO – Kenya Agricultural and Livestock research Organization
• KEBS – Kenya Bureau of Standards
• KEMRI – Kenya Medical Research Institute
• KEPHIS – Kenya Plant Health Inspectorate Service
• MMUST- Masinde Muliro University of Science and Technology
• MoAL&F – Ministry of Agriculture Livestock and Fisheries
• MoH – Ministry of Health
• NGOs – Non-Governmental Organizations
• NIB – National Irrigation Board
• UoN – University of Nairobi
• USDA – ARS – United Stated Department of Agriculture – Agricultural Research Service

17. --
Acknowledgements
1. MRI
2. KALRO
3. EAFF
4. UoN
5. Colleagues

18. --

19. --
Thank you