Fumonisin Contamination Research Articles

The Impact of Fermentation on Aflatoxin and Fumonisin Levels in Sorghum Kernels and Flour Used to Prepare Complementary Food in Kerio Valley, Kenya

ABSTRACTSorghum is a major ingredient used in the production of complementary foods in Kenya's drylands, particularly in areas like Kerio Valley. However, it is known to be susceptible to aflatoxin and fumonisin contamination, which have adverse effects on human health. The current study aimed to assess the levels of aflatoxin and fumonisin in sorghum kernels and flour from Kerio Valley and to investigate whether fermentation (spontaneous or innoculum facilated) could reduce the levels of toxins. The sorghum samples were obtained through a cross‐sectional survey and subjected to ELISA analysis for quantification of aflatoxin and fumonisin levels. The aflatoxin levels ranged from 0 to 119.91 ppb for sorghum kernels and from 2.70 to 89.36 ppb in the flour, while fumonisin concentrations ranged from 0 to 30.65 ppm in sorghum kernels and 0.22 to 27.27 ppm in the flour. Fermentation significantly reduced the levels of the toxins in sorghum samples (p ≤ 0.05). The type of fermentation (p = 0.001), sample fermented (kernels or flour) (p = 0.004), and duration of fermentation (p = 0.037) significantly impacted the reduction of both toxins. Therefore, there is a need to integrate the adoption of fermentation with other effective postharvest practices to mitigate mycotoxin contamination in sorghum and other cereal‐based foods. In addition to the customary health and nutrition messages, promoting proper food handling, storage, and processing can significantly contribute to improving food safety and the overall health and nutritional status of young children.

Assessing the effect of provitamin a on maize field resistance to aflatoxin and fumonisin contamination

Vitamin A deficiency in sub-Saharan Africa is mainly being addressed through crop biofortification. Several high provitamin A (PVA) maize varieties have been released as part of these measures. However, these varieties are grown in areas where Aspergillus ear rot (AER) and Fusarium ear rot (FER) frequently occur, leading to contamination with mycotoxins, which in turn reduce the yield and grain quality. Chronic mycotoxin exposure leads to serious public health problems. Therefore, PVA maize varieties should be resistant to mycotoxin contamination. In a previous study, we generated 120 PVA hybrids by crossing 60 PVA inbreds and two testers with contrasting PVA content. Several inbreds resistant to aflatoxin were detected through laboratory-based kernel screening assays. In the current study, 21 PVA inbred lines with varying carotenoid content inoculated with toxigenic isolates of A. flavus and F. verticillioides were evaluated in field trials conducted at two locations in Nigeria for resistance to ear rots and mycotoxin production. Inbred lines resistant to AER, FER, aflatoxin and fumonisin contamination were identified. High PVA inbred lines were less susceptible to the ear rots, aflatoxin, and fumonisin than those with low PVA content. There were negative correlations between PVA content and each of AER (r = −0.28, P < 0.0001), FER (r = −0.37, P < 0.0001), aflatoxin (r = −0.15, P < 0.05), and fumonisin (r = −0.27, P < 0.0001). Three promising inbred lines were resistant to both aflatoxin and fumonisin. Moreover, the inbred TZI1715 combined resistance to AER, FER, aflatoxin, and fumonisin with desirable general combining ability for high β-carotene and total PVA content. These results suggest that the PVA biofortified maize developed to address vitamin A deficiency can also contribute to reduced exposure to aflatoxin and fumonisin.

Seed Priming with Rhizospheric Bacillus subtilis: A Smart Strategy for Reducing Fumonisin Contamination in Pre-Harvest Maize.

Maize, one of the most important cereal crops in Bangladesh, is severely contaminated by fumonisin, a carcinogenic secondary metabolite produced by Fusarium including Fusarium proliferatum. Biocontrol with Bacillus strains is an effective approach to controlling this F. proliferatum as Bacillus has proven antagonistic properties against this fungus. Therefore, the present study aimed to determine how native Bacillus strains can reduce fumonisin in maize cultivated in Bangladesh, where BDISO76MR (Bacillus subtilis) strains showed the highest efficacy both in vitro in detached cob and in planta under field conditions. The BDISO76MR strain could reduce the fumonisin concentration in detached cob at 98.52% over untreated control, by inhibiting the conidia germination and spore formation of F. proliferatum at 61.56% and 77.01%, respectively in vitro. On the other hand, seed treatment with formulated BDISO76MR showed higher efficacy with a reduction of 97.27% fumonisin contamination compared to the in planta cob inoculation (95.45%) over untreated control. This implies that Bacillus-based formulation might be a potential approach in mitigating fumonisin contamination in maize to ensure safe food and feed.

Self-powered photoelectrochemical aptasensor for fumonisin B1 detection based on a Z-scheme ZnIn2S4/WO3 photoanode

The incidence of esophageal cancer is positively associated with fumonisin contamination. It is necessary to develop methods for the rapid detection of fumonisins. In this work, a self-powered photoelectrochemical aptamer sensor based on ZnIn2S4/WO3 photoanode and Au@W–Co3O4 photocathode is proposed for the sensitive detection of fumonisin B1 (FB1). Among them, under visible light irradiation, the Z-type heterostructure of ZnIn2S4/WO3 acts as a photoanode to improve the electron transfer rate, which contributes to the enhancement of the photocathode signal and lays the foundation for a wider detection range. The Au@W–Co3O4 photocathode as a sensing interface reduces the probability of false positives (comparison of anode sensing platforms). The PEC sensor has a good working performance in the detection range (10 pg/mL-1000 ng/mL) with a detection limit of 2.7 pg/mL (S/N = 3). In addition, the sensor offers good selectivity, stability and excellent recoveries in real sample analysis. This work is expected to play a role in the field of analyzing environmental toxins.

PSV-20 Mycotoxin contamination trends in United States corn grain: 2019-2023

Abstract Mycotoxins are secondary fungal metabolites which may affect animal health, reproduction, and performance. These naturally occurring toxic metabolites are found in a variety of feedstuffs worldwide. Classic signs of mycotoxicosis in livestock can include reduced feed intake, diarrhea, and vomiting. Consideration of clinical signs alone will underestimate the true impact of mycotoxins on animals as inflammation, decreased nutrient digestibility, impaired gut integrity, and altered immune responses have also been associated with mycotoxin exposure. The objective of this study was to compare mycotoxin contamination levels of the 2023 corn crop with previous year trends. Samples were analyzed utilizing the liquid chromatography with tandem mass spectrometry (LC-MS/MS) method for six major mycotoxin groups: aflatoxins (Afla), type A trichothecenes (A-Trich), type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN), and ochratoxin A (OTA). Statistical analyses were performed with JMP Pro 16 software using one-way ANOVA and means were separated using Tukey’s HSD with significance reported at P ≤ 0.05. A limited number of 2023 samples were screened by time of abstract submission (n = 37); therefore, the contamination profile of this crop year will likely change as the sample pool expands and includes more samples originating from the Midwest. Contamination levels in corn for the tested toxin groups have remained consistent over the survey period. To date, 100% of the samples evaluated contained at least one mycotoxin, compared with 91% that was observed in 2022. Aflatoxin occurrence was numerically greater in 2023 corn compared with previous harvest years (27 vs. 11, 7, 5, and 3%, 2022 through 2019, respectively) while Afla mean contamination levels were similar across the study period (P &amp;gt; 0.05). The occurrence of FUM in 2023 corn was also numerically the greatest (97 vs. 79, 64, 64, and 78%, 2022 through 2019, respectively) and mean FUM contamination levels did not differ across the study period (P &amp;gt; 0.05). Occurrence of A-Trich was numerically increased in 2023 vs. 2022 (22 vs. 3%) but mean contamination level of positive samples for A-Trich was significantly less (P &amp;lt; 0.05) in 2023 vs. 2019 (21 vs. 330 parts per billion) and did not differ from other years in the study. The occurrence of B-Trich was numerically less in 2023 vs. 2022 (35 vs. 68%) while B-Trich mean contamination levels were similar across the study period (P &amp;gt; 0.05). Preliminary results of the 2023 US corn grain survey indicate mycotoxin occurrence is numerically increased while mean contamination levels are similar for most mycotoxin groups other than A-Trich. Continued surveillance is advised to assess the risk to livestock as new crop corn is fed out over the coming months.

Encapsulation of Apium graveolens essential oil into chitosan nanobiopolymer for protection of stored rice against Fusarium verticillioides and fumonisins contamination

The present investigation entails the encapsulation of Apium graveolens essential oil into chitosan nanobiopolymer (AGEO-Ne) and assessment of its efficacy against Fusarium verticillioides contamination and fumonisins biosynthesis in stored rice (Oryza sativa L.) samples. The AGEO was encapsulated through ionic gelation process and characterized by scanning electron microscopy (SEM), Dynamic light scattering (DLS), X-ray diffractometry (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses. The AGEO exhibited bi-phasic delivery pattern from chitosan matrix. The AGEO caused complete inhibition of F. verticillioides growth at 1.2 μL/mL, while fumonisin B1 (FB1) and B2 (FB2) biosynthesis at 1.2 and 1.0 μL/mL, respectively. On the other hand, nanoencapsulated AGEO (AGEO-Ne) exhibited improved efficacy, caused complete inhibition of fungal growth at 0.8 μL/mL, and FB1 and FB2 production at 0.8 and 0.6 μL/mL, respectively. AGEO-Ne caused 100 % inhibition of ergosterol synthesis at 0.8 μL/mL and exhibited greater efflux of Ca2+, Mg2+, K+ ions (18.99, 21.63, and 25.38 mg/L) as well as 260 and 280 nm absorbing materials from exposed fungal cells. The in silico interaction of granyl acetate and linalyl acetate with FUM 21 protein validated the molecular mechanism for inhibition of FB1 and FB2 biosynthesis. Further, improvement in antioxidant activity of AGEO-Ne was observed after encapsulation with IC50 values of 12.08 and 6.40 μL/mL against DPPH and ABTS radicals, respectively. During in situ investigation, AGEO caused 82.09 and 86.32 % protection of rice against F. verticillioides contamination in inoculated and uninoculated rice samples, respectively, while AGEO-Ne exhibited 100 % protection of fumigated rice samples against F. verticillioides proliferation as well as FB1 and FB2 contamination. The AGEO-Ne also caused better retardation of lipid peroxidation (41.35 and 37.52 μM/g FW malondialdehyde in inoculated and uninoculated treatment) and acceptable organoleptic properties in rice samples, which strengthen its application as plant based novel preservative in food and agricultural industries.

Phenotypic characterisation and evaluation of resistance to Fusarium ear rot, fumonisin contamination and agronomic traits in a collection of maize landraces

Context Maize is a major crop in Italy and is constantly affected by the fungus Fusarium verticillioides, producing ear rot and grain contamination by fumonisins. Finding new genotypes resistant to Fusarium infection is an important goal for the improvement of maize cultivation. Aims The objective of this work was to test a collection of 33 traditional landraces from the Emilia-Romagna (Italy) region for Fusarium ear rot (FER) severity, fumonisin content, and their agronomic performance. Methods Primary ears were artificially inoculated with a toxigenic strain of F. verticillioides in a 2-year experimental trial. The landrace ‘Nostrano di Storo’ and a commercial hybrid of FAO maturity class 300 were also included and used as comparisons representing a well-known and highly valued landrace and a modern flint hybrid, respectively. Key results The collection showed great phenotypic variability for all the agronomic traits assessed and responded differently to the Fusarium infection with percentages of FER ranging from 6.6% to 49.3%, and fumonisins from 4.3 mg/kg to 34.5 mg/kg. Thirteen and six landraces displayed FER percentages and fumonisin content very similar to the hybrid, respectively. Moreover, eight landraces exhibited grain yield values comparable to the hybrid. Interestingly, Va221, Va227 and EMR03 showed the best combination among these three traits. Conclusions This local material can be considered suitable for breeding purposes targeting the development of FER and fumonisin resistant germplasm. Implications The collection may represent a resource for future research aimed at evaluating the response to multiple pathogens and their associated mycotoxins.

NIR-HSI as a tool to predict deoxynivalenol and fumonisins in maize kernels: a step forward in preventing mycotoxin contamination.

Maize is frequently contaminated with deoxynivalenol (DON) and fumonisins B1 (FB1) and B2 (FB2). In the European Union, these mycotoxins are regulated in maize and maize-derived products. To comply with these regulations, industries require a fast, economic, safe, non-destructive and environmentally friendly analysis method. In the present study, near-infrared hyperspectral imaging (NIR-HSI) was used to develop regression and classification models for DON, FB1 and FB2 in maize kernels. The best regression models presented the following root mean square error of cross validation and ratio of performance to deviation values: 0.848 mg kg-1 and 2.344 (DON), 3.714 mg kg-1 and 2.018 (FB1) and 2.104 mg kg-1 and 2.301 (FB2). Regarding classification, European Union legal limits for DON and FB1 + FB2 were selected as thresholds to classify maize kernels as acceptable or not. The sensitivity and specificity were 0.778 and 1 for the best DON classification model and 0.607 and 0.938 for the best FB1 + FB2 classification model. NIR-HSI can help reduce DON and fumonisins contamination in the maize food and feed chain. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Financial losses due to fumonisin contamination in the Texas High Plains maize

Fumonisins are one of the main problems affecting maize production in the Texas High Plains (THP), where its agroclimatic conditions make it a perennial hotspot for mycotoxin contamination. In 2017, a fumonisin outbreak in the THP maize motivated stakeholders’ request to repeal a subsection of the Texas Administrative Code, §61.61(a)(7) (Fumonisin Rule), and its related Texas Feed Industry Memorandum (Memo 5–20), which previously permitted the blending of maize containing high fumonisin levels with maize containing ≥ 5 mg/kg under state authority, and pivot to FDA fumonisin guidance. Shortly after, the USDA Risk Management Agency (RMA's) reintroduced Discount Factors (DFs) in annual Special Provisions (SP) that outline price reductions related to fumonisin contamination in maize. In this research, we estimate the potential economic burden posed by these changes through a two-part approach. In part one, we construct a decision model that explores the final disposition of fumonisin-contaminated maize based on blending permissions, fumonisin levels, and crop insurance status. In part two, we estimate the economic impact by inserting output values of the decision model into financial equations that consider testing costs, transportation fees, and discounts from crop insurance and grain elevators when applicable. Our economic analysis projects that the financial losses during a THP crop year with high fumonisin levels could range from $15.1 to $135.5 million without the option to blend under conditions of the revised RMA discount schedule. Findings further highlight crop insurance as the most promising risk management strategy for farmers in areas susceptible to fumonisin contamination.

Biophysical factors and agronomic practices associated with Fusarium ear rot and fumonisin contamination of maize in multiple agroecosystems in Ethiopia

AbstractIn Ethiopia, Fusarium ear rot (FER) reduces yield, quality, and safety of maize and negatively impacts the economics of maize growers. However, there is almost no published information on geographic distribution, severity, or causal agents of FER in Ethiopia or levels of preharvest fumonisin contamination, biophysical factors, and agronomic practices associated with FER. Therefore, we surveyed 480 agricultural fields located in 10 Ethiopian zones to assess the incidence and severity of FER as well as agricultural practices and biophysical factors associated with each field. We also determined the concentration of fumonisin in samples taken from the fields. Results revealed that FER was prevalent with varied disease intensity and yield loss levels among the assessed zones. The highest percent severity index (PSI) was recorded in Mirab Wellega (33.2%), with a correspondingly maximum estimated mean grain yield loss of 13.6%, while the minimum disease severity 11.3% and yield loss 5.4% were recorded from the Ilubabor zone. Fumonisins (FB1, FB2, FB3, and FB4) were detected in 98% of the samples, and the levels ranged from 5 to 7517 μg kg−1 (mean, 540 μg kg−1 and median 82.4 μg kg−1). The mean fumonisin contamination of 1524.4, 1316.8, 744.5, and 742.6 μg kg−1 was recorded for Mirab Welega, Misraq Wellega, Assosa, and Hawassa zones, respectively. In total, about 11.3% of the maize samples exceeded the maximum tolerable total fumonisin limit set by the European Union in maize flour (&gt;1000 μg kg−1) and are not suitable for human consumption. Disease severity highly significantly (p &lt; 0.0001) correlated with biophysical factors such as insect infestation (r = 0.60, p &lt; 0.0001) and weed infestation (r = 0.64, p &lt; 0.0001) and agronomic practices such as nitrogen phosphorus sulfur fertilizer application rate (r = −0.39, p &lt; 0.0001) and insecticide spray frequency (r = −0.55, p &lt; 0.0001). Other agronomic practices such as earlier or later sowing date and inter‐cropping systems significantly reduced (p &lt; 0.001) FER incidence, PSI, and the associated grain yield loss. There was significant (p &lt; 0.0001) variation among maize cultivars currently under production in reaction against FER disease intensity. Moreover, the result of the present study attests a strong positive association (p &lt; 0.001) between disease intensity and maize fumonisin concentrations. Generally, the study revealed a wider distribution of FER and fumonisin contamination of maize in the southwest major maize‐growing belts of Ethiopia. Thus, appropriate integrated pre‐harvest ear rot management strategies including the use of resistant cultivars and suitable agronomic practices are recommended for the management of FER and the associated mycotoxins in Ethiopia.

Food Safety Aspects of Breeding Maize to Multi-Resistance against the Major (Fusarium graminearum, F. verticillioides, Aspergillus flavus) and Minor Toxigenic Fungi (Fusarium spp.) as Well as to Toxin Accumulation, Trends, and Solutions-A Review.

Maize is the crop which is most commonly exposed to toxigenic fungi that produce many toxins that are harmful to humans and animals alike. Preharvest grain yield loss, preharvest toxin contamination (at harvest), and storage loss are estimated to be between 220 and 265 million metric tons. In the past ten years, the preharvest mycotoxin damage was stable or increased mainly in aflatoxin and fumonisins. The presence of multiple toxins is characteristic. The few breeding programs concentrate on one of the three main toxigenic fungi. About 90% of the experiments except AFB1 rarely test toxin contamination. As disease resistance and resistance to toxin contamination often differ in regard to F. graminearum, F. verticillioides, and A. flavus and their toxins, it is not possible to make a food safety evaluation according to symptom severity alone. The inheritance of the resistance is polygenic, often mixed with epistatic and additive effects, but only a minor part of their phenotypic variation can be explained. All tests are made by a single inoculum (pure isolate or mixture). Genotype ranking differs between isolates and according to aggressiveness level; therefore, the reliability of such resistance data is often problematic. Silk channel inoculation often causes lower ear rot severity than we find in kernel resistance tests. These explain the slow progress and raise skepticism towards resistance breeding. On the other hand, during genetic research, several effective putative resistance genes were identified, and some overlapped with known QTLs. QTLs were identified as securing specific or general resistance to different toxicogenic species. Hybrids were identified with good disease and toxin resistance to the three toxigenic species. Resistance and toxin differences were often tenfold or higher, allowing for the introduction of the resistance and resistance to toxin accumulation tests in the variety testing and the evaluation of the food safety risks of the hybrids within 2-3 years. Beyond this, resistance breeding programs and genetic investigations (QTL-analyses, GWAM tests, etc.) can be improved. All other research may use it with success, where artificial inoculation is necessary. The multi-toxin data reveal more toxins than we can treat now. Their control is not solved. As limits for nonregulated toxins can be introduced, or the existing regulations can be made to be stricter, the research should start. We should mention that a higher resistance to F. verticillioides and A. flavus can be very useful to balance the detrimental effect of hotter and dryer seasons on aflatoxin and fumonisin contamination. This is a new aspect to secure food and feed safety under otherwise damaging climatic conditions. The more resistant hybrids are to the three main agents, the more likely we are to reduce the toxin losses mentioned by about 50% or higher.

Atoxigenic Aspergillus flavus (Aflasafe KE01) application reduces Fumonisin contamination in maize in lower Eastern Kenya

Management of fumonisin contamination in maize has been a challenge largely because there are no effective management measures for Fusarium ear rots. Maize varieties that are resistant to fumonisin contamination are also lacking. This study was conducted to determine the efficacy of atoxigenic Aspergillus flavus (Aflasafe KE01) on fumonisin contamination of maize. The study was carried out in four sub-counties in lower Eastern Kenya. Twenty-four maize fields were selected in each sub-county; where 12 fields were treated with Aflasafe KE01, while 12 fields comprised the untreated controls. Aflasafe KE01 was applied at a rate of 5 kg/ha and 10kg/ha by hand broadcasting in maize fields two to three weeks before tasselling of maize. Fumonisin level in the maize samples was determined using Accuscan Pro-reader enzyme-linked immunosorbent assay (ELISA). The results showed that application of Aflasafe KE01 reduced fumonisin in the maize from the Aflasafe KE01 treated fields by up to 68% compared to samples from untreated fields. About 62.5% of the maize fields treated with 5kg/ha of Aflasafe KE01 met the European Commission regulatory threshold of ≤2ppm for total fumonisin as compared to about 45% from the control fields. This indicates that Aflasafe KE01 is a potential biopesticide for the management of fumonisin in maize. Therefore, efficacy of Aflasafe KE01 to reduce fumonisin contamination of other key staples in Kenya should also be evaluated. Key words: Aflasafe KE01, atoxigenic Aspergillus sp., fumonisins, maize.

Efficacy of Pinus roxburghii Sarg. essential oil against Fusarium proliferatum and fumonisin contamination in stored rice samples

The present study entails first time investigation on chemical characterisation of Pinus roxburghii essential oil (PEO) with its efficacy assessment against Fusarium proliferatum contamination and fumonisin synthesis in stored rice samples. The GC-MS analysis indicated α-Pinene, terpinolene, and O-cymene as major components of PEO. The PEO displayed complete inhibition of F. proliferatum growth and fumonisin B1, B2 biosynthesis at 1.5, 1.0, and 0.75 µL/mL, respectively. The antifungal activity of PEO was associated with impairment in ergosterol biosynthesis and enhanced leakage of vital cellular cations (Ca2+, Mg2+, and K+), nucleic acids, and proteins which validated plasma membrane as a plausible site of action. Moreover, the PEO showed promising antioxidant activity and in situ efficacy for preservation of rice samples against F. proliferatum infestation, and fumonisin B1, B2 contamination. Further, the high LD50 value in mammalian model strengthens the application of Pinus roxburghii essential oil as green fungitoxicant in agricultural industries.

Genome-wide transcriptome analysis of toxigenic Fusarium verticillioides in response to variation of temperature and water activity on maize kernels

Fusarium verticillioides is one of the important mycotoxigenic pathogens of maize since it causes severe yield losses and produces fumonisins (FBs) to threaten human and animal health. Previous studies showed that temperature and water activity (aw) are two pivotal environmental factors affecting F. verticillioides growth and FBs production during maize storage. However, the genome-wide transcriptome analysis of differentially expressed genes (DEGs) in F. verticillioides under the stress combinations of temperature and aw has not been studied in detail. In this study, DEGs of F. verticillioides and their related regulatory pathways were analyzed in response to the stress of temperature and aw combinations using RNA-Seq. The results showed that the optimal growth conditions for F. verticillioides were 0.98 aw and 25 °C, whereas the highest per-unit yield of the fumonisin B1 (FB1) was observed at 0.98 aw and 15 °C. The RNA-seq analysis showed that 9648 DEGs were affected by temperature regardless of aw levels, whereas only 218 DEGs were affected by aw regardless of temperature variations. Gene Ontology (GO) analysis revealed that a decrease in temperature at both aw levels led to a significant upregulation of genes associated with 24 biological processes, while three biological processes were downregulated. Furthermore, when aw was decreased at both temperatures, seven biological processes were significantly upregulated and four were downregulated. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that the genes, whose expression was upregulated when the temperature decreased, were predominantly associated with the proteasome pathway, whereas the genes, whose expression was downregulated when the aw decreased, were mainly linked to amino acid metabolism. For the FB1, except for the FUM15 gene, the other 15 biosynthetic-related genes were highly expressed at 0.98 aw and 15 °C. In addition, the expression pattern analysis of other biosynthetic genes involved in secondary metabolite production and regulation of fumonisins production was conducted to explore how this fungus responds to the stress combinations of temperature and aw. Overall, this study primarily examines the impact of temperature and aw on the growth of F. verticillioides and its production of FB1 using transcriptome data. The findings presented here have the potential to contribute to the development of novel strategies for managing fungal diseases and offer valuable insights for preventing fumonisin contamination in food and feed storage.

Dynamic geospatial modeling of mycotoxin contamination of corn in Illinois: unveiling critical factors and predictive insights with machine learning.

Mycotoxin contamination of corn is a pervasive problem that negatively impacts human and animal health and causes economic losses to the agricultural industry worldwide. Historical aflatoxin (AFL) and fumonisin (FUM) mycotoxin contamination data of corn, daily weather data, satellite data, dynamic geospatial soil properties, and land usage parameters were modeled to identify factors significantly contributing to the outbreaks of mycotoxin contamination of corn grown in Illinois (IL), AFL >20 ppb, and FUM >5 ppm. Two methods were used: a gradient boosting machine (GBM) and a neural network (NN). Both the GBM and NN models were dynamic at a state-county geospatial level because they used GPS coordinates of the counties linked to soil properties. GBM identified temperature and precipitation prior to sowing as significant influential factors contributing to high AFL and FUM contamination. AFL-GBM showed that a higher aflatoxin risk index (ARI) in January, March, July, and November led to higher AFL contamination in the southern regions of IL. Higher values of corn-specific normalized difference vegetation index (NDVI) in July led to lower AFL contamination in Central and Southern IL, while higher wheat-specific NDVI values in February led to higher AFL. FUM-GBM showed that temperature in July and October, precipitation in February, and NDVI values in March are positively correlated with high contamination throughout IL. Furthermore, the dynamic geospatial models showed that soil characteristics were correlated with AFL and FUM contamination. Greater calcium carbonate content in soil was negatively correlated with AFL contamination, which was noticeable in Southern IL. Greater soil moisture and available water-holding capacity throughout Southern IL were positively correlated with high FUM contamination. The higher clay percentage in the northeastern areas of IL negatively correlated with FUM contamination. NN models showed high class-specific performance for 1-year predictive validation for AFL (73%) and FUM (85%), highlighting their accuracy for annual mycotoxin prediction. Our models revealed that soil, NDVI, year-specific weekly average precipitation, and temperature were the most important factors that correlated with mycotoxin contamination. These findings serve as reliable guidelines for future modeling efforts to identify novel data inputs for the prediction of AFL and FUM outbreaks and potential farm-level management practices.

Phytochemicals reduced growth, sporulation and conidial dimensions of Fusarium verticillioides, cause of fumonisin contamination in maize grains

The objective of the study was to evaluate the effectiveness of methanolic extracts of plants against radial growth and spore dimensions of Fusarium verticillioides. Leaf extracts of 25 plants were tested against the fungus. Of which, thirteen extracts were potent against the fungus and evaluated using food poising technique. Growth was evaluated on PDA medium amended with the extracts at 5 mg ml–1. Control treatments included plates without (negative) extracts and with synthetic (positive) fungicide. Spore dimension was determined using PDB. The results showed T. vulgaris extract completely inhibited mycelial growth of the fungus as equivalent as the fungicide. Similarly, G. parviflora, C. citratus, R. officinalis, R. chalepensis, and Agave sp. also recorded growth reductions ranging from 71.04 to 81.35 % at day seven. In addition, extracts of Agave sp., C. citratus and T. vulgaris did not support sporulation. Overall, the results indicate that T. vulgaris extracts could be safe source of bioactive chemicals to control F. verticillioides.

Quantitative risk assessment of the presence of fumonisin in corn produced in different regions of Brazil: Influence of climatic conditions

In this study, the probability of occurrence of fumonisins in corn in the states of greatest production in Brazil was determined. The data were analyzed through quantitative risk analysis using the Monte Carlo simulation. The results indicated that there is a strong correlation between fumonisins contamination levels and the geographical region due to the influence of climatic characteristics, with temperature having the main influence. The Southern states presented higher risks of occurrence and concentration levels of fumonisins in corn due to the temperate climate with lower average temperature and higher relative humidity and precipitation indices. Cultivation in the best season indicates a significant reduction in the production of fumonisins when this period was evaluated, with average concentration levels up to 42% lower. The generated data are important for regulatory agencies and the agricultural sector, which needs to be aware that the chance of success in grain production depends on efficient planning of the growing season, mainly concerning the climatic conditions to which it is subject to minimize the risks.

Health Implication of Mycotoxigenic Fungi and Mycotoxins Analysed from Sun Dried Yam and Potato Chips Sold in Minna Niger State, Nigeria

Mycotoxin is toxic secondary metabolite synthesized by filamentous fungi during their stationary phase of growth in agricultural crops, food and feed products. Niger State experienced high temperature and humidity for about three-quarters of the year, and these are some of the conditions that encourage filamentous fungi to produce mycotoxin in food products. Enzyme Linked Immunosorbent Assay (ELISA) was used to dectect mycotoxins. Mycological profile and mycotoxins of sun dried yam and potato chips was determined. Total of fifty (50) samples were collected randomly from five markets in Minna and its environs. 179 isolates were recorded. Aspergillus species 86(53.1 %) Mucor species 27(15.1 %), yeast species 25(13.9 %) Penicillium species 14(7.8 %), Fusarium species 14(7.8 %) Rhizopus species 3(1.7 %) and Microsporum species 1(0.6 %) were the common fungi. The highest mean fungal counts (12.8 x 103 cfu/g) were observed in sweet potato chips bought in Gwada market while the lowest (3.5 x 103 cfu/g), was observed in Yam chips from Paiko market. The mean moisture content of 7.41±2.28 % was recorded in potato chips and yam chips had the lowest moisture content of 4.72± 1.66 %. Total aflatoxins, fumonisin and zearalenone contents were detected in 48 (96 %) of the samples. In yam and potato chips, total aflatoxin contamination was 68 and 84 % with mean concentrations of 12.6±7.36 μg/kg and 10.3±13.81 μg/kg respectively. The total aflatoxin concentration range of yam and potato chips were 0-61.84 μg/kg and 0-54.49 μg/kg with 28 and 48 % of the samples below 4μg/kg E.U limit respectively. Fumonisin contamination was 80 and 60% with mean concentrations of 928.123±559.50 μg/kg and 722.64 ± 137.85 μg/kg with a range 0.0-4018.24 μg/kg and 0 – 2055.98 μg/kg and had 52 and 72 % below 1000 μg/kg acceptable limit for yam and potato chips respectively. Zearalenone contamination in yam and potato account for 56 and 68% having mean concentration of 16.33± 9.71 μg/kg and 24.12± 21.03 μg/kg with a range 0 – 45.53 μg/kg and 0 – 83.74 μg/kg respectively. All the samples contaminated with Zearalenone were below the E.U regulatory limit of 100 μg/kg for food stuff intended for direct consumption. Dietary exposure and risk characterisation (EDI and %TDI) were further estimated for total aflatoxins, fumonisin and zearalenone. It was concluded that the level of contamination of these chips with mycotoxins poses a serious threat to public health and there is the need for proactive approach to drastically reduce fungal contamination.

Multispectral Sorting Based on Visibly High-Risk Kernels Sourced from Another Country Reduces Fumonisin and Toxigenic Fusarium on Maize Kernels

Fusarium species infect maize crops leading to the production of fumonisin by their toxigenic members. Elimination of microbes is critical in mitigating further postharvest spoilage and toxin accumulation. The current study investigates the efficacy of a previously described multispectral sorting technique to analyze the reduction of fumonisin and toxigenic Fusarium species found contaminating maize kernels in Kenya. Maize samples (n = 99) were collected from six mycotoxin hotspot counties in Kenya (Embu, Meru, Tharaka Nithi, Machakos, Makueni, and Kitui County) and analyzed for aflatoxin and fumonisin using commercial ELISA kits. Aflatoxin levels in majority (91%) of the samples were below the 10 ng/g threshold set by the Kenya Bureau of Standards and therefore not studied further. The 23/99 samples that had >2,000 ng/g of fumonisin were selected for sorting. The sorter was calibrated using kernels sourced from Ghana to reject visibly high-risk kernels for fumonisin contamination using reflectance at nine distinct wavelengths (470–1,550 nm). Accepted and rejected streams were tested for fumonisin using ELISA, and the presence of toxigenic Fusarium using qPCR. After sorting, there was a significant (p < 0.001) reduction of fumonisin, by an average of 1.8 log ng/g (98%) and ranging between 0.14 and 2.7 log ng/g reduction (28–99.8%) with a median mass rejection rate of 1.9% (ranged 0% to 48%). The fumonisin rejection rate ranged between 0 and 99.8% with a median of 77%. There was also a significant reduction (p = 0.005) in the proportion of DNA represented by toxigenic Fusarium, from a mean of 30–1.4%. This study demonstrates the use of multispectral sorting as a potential postharvest intervention tool for the reduction of Fusarium species and preformed fumonisin. The spectral sorting approach of this study suggests that classification algorithms based on high-risk visual features associated with mycotoxin can be applied across different sources of maize to reduce fumonisin.

Maize kernel metabolome involved in resistance to fusarium ear rot and fumonisin contamination.

Fusarium verticillioides poses a threat to worldwide maize production due to its ability to infect maize kernel and synthesize fumonisins that can be accumulated above safety levels for humans and animals. Maize breeding has been proposed as key tool to decrease kernel contamination with fumonisins, but metabolic studies complementary to genomic approaches are necessary to disclose the complexity of maize resistance. An untargeted metabolomic study was proposed using inbreds genetically related but with contrasting levels of resistance in order to uncover pathways implicated in resistance to Fusarium ear rot (FER) and fumonisin contamination in the maize kernel and to look for possible biomarkers. Metabolite determinations were performed in kernels collected at 3 and 10 days after inoculation with F. verticillioides (dat). Discriminant metabolites between resistant and susceptible RILs were rather found at 10 than 3 dat, although metabolite differences at later stages of colonization could be driven by subtle variations at earlier stages of infection. Within this context, differences for membrane lipid homeostasis, methionine metabolism, and indolacetic acid conjugation seemed highly relevant to distinguish between resistant and susceptible inbreds, confirming the polygenic nature of resistance to FER and fumonisin contamination in the maize kernels. Nevertheless, some specific metabolites such as the polyamine spermidine and/or the alkaloid isoquinoline seemed to be promising indirect selection traits to improve resistance to FER and reduce fumonisin accumulation. Therefore, in vitro and in vivo experiments will be necessary to validate the inhibitory effects of these compounds on fumonisins biosynthesis.