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This book evaluates the risks to human and animal health posed by the consumption of maize and maize-based products contaminated with fumonisin B1. This naturally occurring mycotoxin produced by the mould Fusarium verticillioides is found in high concentrations throughout the world and is believed to be the most prevalent and toxic of the fumonisins. Consumption is known to cause two fatal diseases in farm animals. Possible adverse effects on human health are of particular importance in several developing countries where maize and maize-based products are the staple food for large populations

Maize and other cereals are the commodities most contaminated with fumonisins. The maize acreage is increasing in Africa, and the maize harvest provides important foods for humans and feeds for domestic animals throughout the continent. In North Africa, high levels of fumonisins have been reported from Algeria and Morocco, while low levels have been detected in the rather few fumonisin analyses reported from Tunisia and Egypt. The West African countries Burkina Faso, Cameroon, Ghana, and Nigeria all report high levels of fumonisin contamination of maize, while the few maize samples analysed in Togo contain low levels. In Eastern Africa, high levels of fumonisin contamination have been reported from the Democratic Republic of Congo, Ethiopia, Kenya, Tanzania, and Uganda. The samples analysed from Rwanda contained low levels of fumonisins. Analysis of maize from the Southern African countries Malawi, Namibia, South Africa, Zambia, and Zimbabwe revealed high fumonisin levels, while low levels of fumonisins were detected in the few analyses of maize from Botswana and Mozambique.

In order to calculate the dietary fumonisin intake of the German consumer, a large survey was carried out on a variety of potentially contaminated products in the period between December 1998 and July 2001. A total of 1960 food samples comprising all known relevant groups of products were analysed for fumonisins. Furthermore, 272 of these samples were also analysed for hydrolysed fumonisins (HFB). For routine analysis enzyme immunoassay was used, confirmatory and control analyses were performed using HPLC-FLD after precolumn derivatisation, or by LC-MS/MS. Daily intake of fumonisins was calculated by combining fumonisin contamination data obtained in this study with available food consumption data for Germany. In a "mean case" scenario, median fumonisin levels in foods and mean food intake values were used. To generate a "bad case" scenario, the 90th percentile of fumonisin levels in foods and mean food intake values were combined. The overall daily fumonisin intake by the German consumer was 1.1 ?g in the "mean case" scenario, and 21 ?g in the "bad case" scenario. It was concluded that in general there is no increased risk for the German consumer in aspects of exceeding the recommended tolerable daily intake of fumonisins (2 ?g/kg body weight). However, certain products (and certain brands of products) were repeatedly found to contain elevated fumonisin levels, which in a "worst case" scenario ("high" food intake of maize-based products) could pose a potential risk for the consumer, in particular concerning foods for infants and young children. High fumonisin levels were found in infant foods in 1999, but contamination levels decreased strongly in the following years. HFBs (mostly HFB1) were frequently found in processed cereals such as corn flakes, but in relatively low concentrations. According to our findings, the new European Union maximum levels for fumonisins are suitable to eliminate peak contamination levels of fumonisins in foods, but would lead to a regular excess of the TDI for infants and young children if these maximum levels would indeed be exhausted.

Genetic improvement is an emerging method to reduce the levels of fumonisin (FB) contamination in maize, but breeding advances depend on the development of suitable methods to accurately assess the performance of different cultivars. Our study focused on characterizing a local isolate of Fusarium verticillioides; comparing artificial inoculation techniques with this isolate (injection into kernels and down the silk channel); and assessing white maize resistance under artificial vs. natural inoculation. The fungal growth rate significantly increased with temperature and water activity aw. The optimum growth rate, corresponding with the shortest phase of initial growth, occurred at 25–30 °C and 0.99 aw. Under silk inoculation with this isolate, the hybrid EP10 × EC22 accumulated significantly less FBs than the other hybrids, whereas, under kernel inoculation, differences among hybrids were not significant (P ≤ 0.05). The local isolate of F. verticillioides produced FBs and responded to the usual environmental conditions during maize kernel ripening in northwestern Spain. Inoculation with this isolate is recommended because it is aggressive, toxigenic, and adapted to the local environment. Silk inoculation was the only method that allowed a clear distinction among genotypes based on differences in resistance to FB accumulation. Resistance to natural and artificial inoculations was confirmed for the hybrid EP10 × EC22. ; This research was supported by the National Plan for Research and Development of Spain (AGL2009-12770), the Autonomous Government of Galicia (PGIDIT06TAL40301PR) and the Excma. Diputación Provincial de Pontevedra. A. Cao acknowledges funding from the JAE Program of the Spanish Council of Research. R. Santiago acknowledges postdoctoral contract "Isidro Parga Pondal" supported by the Autonomous Government of Galicia and the European Social Fund.

Genetic improvement is an emerging method to reduce the levels of fumonisin (FB) contamination in maize, but breeding advances depend on the development of suitable methods to accurately assess the performance of different cultivars. Our study focused on characterizing a local isolate of Fusarium verticillioides; comparing artificial inoculation techniques with this isolate (injection into kernels and down the silk channel); and assessing white maize resistance under artificial vs. natural inoculation. The fungal growth rate significantly increased with temperature and water activity a w. The optimum growth rate, corresponding with the shortest phase of initial growth, occurred at 25-30 °C and 0.99 a w. Under silk inoculation with this isolate, the hybrid EP10 × EC22 accumulated significantly less FBs than the other hybrids, whereas, under kernel inoculation, differences among hybrids were not significant (P ≤ 0.05). The local isolate of F. verticillioides produced FBs and responded to the usual environmental conditions during maize kernel ripening in northwestern Spain. Inoculation with this isolate is recommended because it is aggressive, toxigenic, and adapted to the local environment. Silk inoculation was the only method that allowed a clear distinction among genotypes based on differences in resistance to FB accumulation. Resistance to natural and artificial inoculations was confirmed for the hybrid EP10 × EC22. © 2013 KNPV. ; MINECO ; Autonomous Government of Galicia ; Excma. Diputación Provincial de Pontevedra ; Spanish Council of Research ; European Social Fund ; This research was supported by the National Plan for Research and Development of Spain (AGL2009-12770), the Autonomous Government of Galicia (PGIDIT06TAL40301PR) and the Excma. Diputación Provincial de Pontevedra. A. Cao acknowledges funding from the JAE Program of the Spanish Council of Research. R.Santiago acknowledges postdoctoral contract "Isidro Parga Pondal" supported by the Autonomous Government of Galicia and the European Social Fund. ; Peer Reviewed

[Background] Plant breeding has been proposed as one of the most effective and environmentally safe methods to control fungal infection and to reduce fumonisin accumulation. However, conventional breeding can be hampered by the complex genetic architecture of resistance to fumonisin accumulation and marker-assisted selection is proposed as an efficient alternative. In the current study, GWAS has been performed for the first time for detecting high-resolution QTL for resistance to fumonisin accumulation in maize kernels complementing published GWAS results for Fusarium ear rot. ; [Results] Thirty-nine SNPs significantly associated with resistance to fumonisin accumulation in maize kernels were found and clustered into 17 QTL. Novel QTLs for fumonisin content would be at bins 3.02, 5.02, 7.05 and 8.07. Genes with annotated functions probably implicated in resistance to pathogens based on previous studies have been highlighted. ; [Conclusions] Breeding approaches to fix favorable functional variants for genes implicated in maize immune response signaling may be especially useful to reduce kernel contamination with fumonisins without significantly interfering in mycelia development and growth and, consequently, in the beneficial endophytic behavior of Fusarium verticillioides. ; This research was funded by the Autonomous Government of Galicia, Spain (project IN607A/013), and by the "Secretaría de Estado de Investigación, Desarrollo e Innovación", Spain, within the projects AGL2015–67313-C2–1-R and AGL2015–67313-C2–2-R, which were co-financed with European Social Funds. R. Santiago acknowledges postdoctoral contract "Ramón y Cajal" financed by the "Secretaría de Estado de Investigación, Desarrollo e Innovación" and co-financed by the "Universidad de Vigo", Spain, and the European Social Funds.

Fumonisins are major mycotoxins found worldwide in maize and maize products. Because of their toxicity for both human and animals, European Union regulations were created to fix the maximal fumonisin B1 and B2 content allowed in foods and feeds. Unfortunately, directly measuring these mycotoxins by current analytical techniques is tedious and expensive and most measurement methods do not lend themselves to online control. Alternative approaches to chemical analysis have been developed and involve models that allow the mycotoxin contamination to be predicted based on environmental conditions and analysis by near-infrared (NIR) spectroscopy. In the present work, we use NIR spectroscopy to determine the fumonisin and fungal contents of 117 samples of maize. The determination coefficient between fumonisin and fungal-biomass content was 0.44. We establish herein a threshold for the number of CFUs for fungal biomass beyond which the fumonisin content is likely to exceed the European regulatory level of 4000 μg/kg. In addition, we determine the fungal content by using a NIR-spectroscopy model that allows us to sort samples of maize. Upon calibration, the percentage of well-classified samples was 96%, which compares favorably to the 82% obtained by independent verification.

International audience ; Fumonisins are major mycotoxins found worldwide in maize and maize products. Because of their toxicity for both human and animals, European Union regulations were created to fix the maximal fumonisin B1 and B2 content allowed in foods and feeds. Unfortunately, directly measuring these mycotoxins by current analytical techniques is tedious and expensive and most measurement methods do not lend themselves to online control. Alternative approaches to chemical analysis have been developed and involve models that allow the mycotoxin contamination to be predicted based on environmental conditions and analysis by near-infrared (NIR) spectroscopy. In the present work, we use NIR spectroscopy to determine the fumonisin and fungal contents of 117 samples of maize. The determination coefficient between fumonisin and fungal-biomass content was 0.44. We establish herein a threshold for the number of CFUs for fungal biomass beyond which the fumonisin content is likely to exceed the European regulatory level of 4000 μg/kg. In addition, we determine the fungal content by using a NIR-spectroscopy model that allows us to sort samples of maize. Upon calibration, the percentage of well-classified samples was 96%, which compares favorably to the 82% obtained by independent verification.

International audience ; Fumonisins are major mycotoxins found worldwide in maize and maize products. Because of their toxicity for both human and animals, European Union regulations were created to fix the maximal fumonisin B1 and B2 content allowed in foods and feeds. Unfortunately, directly measuring these mycotoxins by current analytical techniques is tedious and expensive and most measurement methods do not lend themselves to online control. Alternative approaches to chemical analysis have been developed and involve models that allow the mycotoxin contamination to be predicted based on environmental conditions and analysis by near-infrared (NIR) spectroscopy. In the present work, we use NIR spectroscopy to determine the fumonisin and fungal contents of 117 samples of maize. The determination coefficient between fumonisin and fungal-biomass content was 0.44. We establish herein a threshold for the number of CFUs for fungal biomass beyond which the fumonisin content is likely to exceed the European regulatory level of 4000 μg/kg. In addition, we determine the fungal content by using a NIR-spectroscopy model that allows us to sort samples of maize. Upon calibration, the percentage of well-classified samples was 96%, which compares favorably to the 82% obtained by independent verification.

Layer feeds in Africa largely comprise cereals that are susceptible to mycotoxin contamination. Mycotoxins pose a health and production hazard in the poultry industry. This study investigated the mycoflora associated with layer feeds and mycotoxin content. 50 samples each of chick mash, grower mash, and layer mash were sampled from five regions in Nairobi County where urban poultry farming is carried out. Dilution plate technique was used to isolate fungi in Potato Dextrose Agar (PDA) and identified using morphological and molecular methods. Total aflatoxins (AF) and total fumonisins (FUM) levels were screened using Enzyme-Linked Immunosorbent Assay (ELISA). Aspergillus (91%), Penicillium (77%), Fusarium (13%), Mucor (11%), Rhizopus (9%), Cladosporium (4%), and Cochliobolus (1%) were isolated. AF was detected in 65% of feed samples (0.22 μg/kg - 157.89 μg/kg) while FUM in 91% of feed samples (210 μg/kg - 15173 μg/kg). Sixty-two samples (42%) had AF levels greater than the Kenya Bureau of Standards (KEBS) recommended limit of 10 μg/kg in poultry feed. No sample contained FUM levels higher than the European Union (EU) recommended limit of 20000 μg/kg. Our results highlight AF contamination in farms in the County, raising concern to poultry and public health due to AF residues in eggs.

Mycotoxins are a crucial problem for poultry production worldwide. Two of the most frequently found mycotoxins in feedstuffs are deoxynivalenol (DON) and fumonisins (FUM) which adversely affect gut health and poultry performance. The current knowledge on DON and FUM effects on broiler responses relevant for gut detoxification, antioxidant capacity, and health is still unclear. The aim of this study was to assess a range of selected molecular intestinal biomarkers for their responsiveness to the maximum allowable European Union dietary levels for DON (5 mg/kg) and FUM (20 mg/kg) in broilers. For the experimental purpose, a challenge diet was formulated, and biomarkers relevant for detoxification, antioxidant response, stress, inflammation, and integrity were profiled across the broiler intestine. The results reveal that DON significantly (p < ; 0.05) induced aryl hydrocarbon receptor (AhR) and cytochrome P450 enzyme (CYP) expression mainly at the duodenum. Moreover, DON and FUM had specific significant (p < ; 0.05) effects on the antioxidant response, stress, inflammation, and integrity depending on the intestinal segment. Consequently, broiler molecular responses to DON and FUM assessed via a powerful palette of biomarkers were shown to be mycotoxin and intestinal site specific. The study findings could be highly relevant for assessing various dietary bioactive components for protection against mycotoxins.

Mycotoxins are a crucial problem for poultry production worldwide. Two of the most frequently found mycotoxins in feedstuffs are deoxynivalenol (DON) and fumonisins (FUM) which adversely affect gut health and poultry performance. The current knowledge on DON and FUM effects on broiler responses relevant for gut detoxification, antioxidant capacity, and health is still unclear. The aim of this study was to assess a range of selected molecular intestinal biomarkers for their responsiveness to the maximum allowable European Union dietary levels for DON (5 mg/kg) and FUM (20 mg/kg) in broilers. For the experimental purpose, a challenge diet was formulated, and biomarkers relevant for detoxification, antioxidant response, stress, inflammation, and integrity were profiled across the broiler intestine. The results reveal that DON significantly (p < 0.05) induced aryl hydrocarbon receptor (AhR) and cytochrome P450 enzyme (CYP) expression mainly at the duodenum. Moreover, DON and FUM had specific significant (p < 0.05) effects on the antioxidant response, stress, inflammation, and integrity depending on the intestinal segment. Consequently, broiler molecular responses to DON and FUM assessed via a powerful palette of biomarkers were shown to be mycotoxin and intestinal site specific. The study findings could be highly relevant for assessing various dietary bioactive components for protection against mycotoxins.