Kenya Agricultural & Livestock Research Organization (KALRO)

Overview of Aflatoxin Research Activities in KENYA

Charles NkongePresentation to the Excursion Meeting on “Networking on

aflatoxin Reduction in food value Chain” held at KALRO HQ on 15/8/16

Actors involvedResearch 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

IntroductionMost 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.

Aflatoxin Contamination Predisposing factorsEnvironmental 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?

Summary of Research Carried out

1.Surveys, Mapping out Aflatoxin hot spots1.1 Aflacontrol – ACDI/VOCA and KALROPrevalence 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

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 UniversityA

3. Aflatoxins in maize value chainsAflatoxins 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.

4. Feeds, Livestock/ dairy value chains4.1 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 high4.2 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)

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.

6. Aflatoxin Detoxification6.1 NixtamilzationLed 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.

5. Aflatoxin Detoxification continued-----5.2 Effect of dehulling maizeResearchers 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 fermentationUsing 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.

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.

Way ForwardQuite a bit of work has been done in several research areas on aflatoxinThe following is what I think some of the gaps that need to be plugged1. 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 priority4. There is urgent need to develop alternative non-food commercial use of contaminated

grain to cut down on losses incurred.

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

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

-- Acknowledgements

1. MRI2. KALRO3. EAFF4. UoN5. Colleagues

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Thank you