Deoxynivalenol and other selected Fusarium toxins in Swedish wheat--occurrence and correlation to specific Fusarium species

The influence of different abiotic conditions on the concentrations of free and conjugated deoxynivalenol and zearalenone in stored wheat

Environmental factors influence fungal growth and mycotoxin production in stored grains. However, the concentrations of free mycotoxins and their conjugates and how they are impacted by different interacting environment conditions have not been previously examined. The objectives of this study were to examine the impact of storage conditions (0.93-0.98 aw) and temperature (20-25 °C) on (a) the concentrations of deoxynivalenol and zearalenone and their respective glucosides/conjugates and (b) the concentrations of emerging mycotoxins in both naturally contaminated and irradiated wheat grains inoculated with Fusarium graminearum. Contaminated samples were analysed for multiple mycotoxins using Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). Method validation was performed according to the acceptable performance criteria set and updated by the European Commission regulations No. 2021/808/EC. As an important conjugate of deoxynivalenol, the concentrations of deoxynivalenol-3-glucoside were significantly different from its precursor deoxynivalenol at 0.93 aw (22% moisture content- MC) at 25 °C in the naturally contaminated wheat with a ratio proportion of 56:44% respectively. The high concentrations of deoxynivalenol-3-glucoside could be influenced by the wheat's variety and/or harvested season/fungal strain type/location. Zeralenone-14-sulfate concentrations were surprisingly three times higher than Zearalenone in the naturally contaminated wheat at 0.98 aw (26% MC) at both temperatures. Emerging mycotoxins such as moniliformin increased with temperature rise with the highest concentrations at 0.95 aw and 25 °C. These findings highlight the influence and importance of storage aw x temperature conditions on the relative presence of free vs conjugated mycotoxins which can have implications for food safety.

Shifts in Fusarium Communities and Mycotoxins in Maize Residues, Soils, and Wheat Grains throughout the Wheat Cycle: Implications for Fusarium Head Blight Epidemiology

Fusarium Head Blight (FHB), predominantly caused by Fusarium species, is a devastating cereal disease worldwide. While considerable research has focused on Fusarium communities in grains, less attention has been given to residues and soil, the primary inoculum sources. Knowledge of Fusarium spp. diversity, dynamics, and mycotoxin accumulation in these substrates is crucial for assessing their contribution to wheat head infection and the complex interactions among Fusarium communities throughout the wheat cycle. We monitored six minimum-tillage wheat fields, with maize as the preceding crop, over two years. Soils, maize residues, and wheat grains were sampled at four stages. Fusarium composition was analyzed using a culture-dependent method, species-specific qPCR, and EF1α region metabarcoding sequencing, enabling species-level resolution. The Fusarium communities were primarily influenced by substrate type, accounting for 35.8% of variance, followed by sampling location (8.1%) and sampling stage (3.2%). Among the 32 identified species, F. poae and F. graminearum dominated grains, with mean relative abundances of 47% and 29%, respectively. Conversely, residues were mainly contaminated by F. graminearum, with a low presence of F. poae, as confirmed by species-specific qPCR. Notably, during periods of high FHB pressure, such as in 2021, F. graminearum was the dominant species in grains. However, in the following year, F. poae outcompeted F. graminearum, resulting in reduced disease pressure, consistent with the lower pathogenicity of F. poae. Source Tracker analysis indicated that residues were a more significant source of Fusarium contamination on wheat in 2021 compared to 2022, suggesting that F. graminearum in 2021 primarily originated from residues, whereas F. poae's sources of infection need further investigation. Additionally, multiple mycotoxins were detected and quantified in maize residues during the wheat cycle, raising the question of their ecological role and impact on the soil microbiota.

Co-contamination and interactions of multiple mycotoxins and heavy metals in rice, maize, soybeans, and wheat flour marketed in Shanghai City

Mycotoxins and heavy metals extensively contaminate grains and grain products, posing severe health risks. This work implements validated ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and inductively coupled plasma mass spectrometry (ICP-MS) methods to quantify the concentration of 12 mycotoxins and five heavy metals in rice, maize, soybeans, and wheat flour samples marketed in Shanghai. The mixed contamination characteristics were analyzed using correlation cluster analysis and co-contamination index, and the probabilities of all cross combinations of contaminations were analyzed using a self-designed JAVA language program. The results showed that grains and grain products were frequently contaminated with both mycotoxins and heavy metals, mostly with deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), 15-acetyl-deoxynivalenol (15-ADON), ochratoxin A (OTA), aflatoxins, fumonisin B1 (FB1), fumonisin B2 (FB2), fumonisin B3 (FB3), arsenic (As), chromium (Cr) and cadmium (Cd). All the samples (100 %) were contaminated with two or more contaminants, and 77.3 % of the samples were co-contaminated with more than four contaminants. In cereals and cereal products, the following combinations were closely associated: (FB3 +3-ADON), (FB1 +As), (FB1 +FB2), (DON+FB1), (DON+Cd), (As+Cd), (DON+Cd+As), (FB1 +FB2 +As), and (DON+3-ADON+15-ADON). The results indicated that mycotoxins and heavy metals frequently co-occurred in Shanghai grains and grain products, and they provided primary data for safety assessments, early warnings, and regulatory measures on these contaminants to protect public health.

A comparison between the role of enniatins and deoxynivalenol in Fusarium virulence on different tissues of common wheat

BACKGROUND

Fusarium graminearum and Fusarium avenaceum are two of the most important causal agents of Fusarium head blight (FHB) of wheat. They can produce mycotoxins that accumulate in infected wheat heads, including deoxynivalenol (DON) and enniatins (ENNs), produced by F. graminearum and F. avenaceum, respectively. While the role of DON as a virulence factor in F. graminearum toward wheat is well known, ENNs in F. avenaceum has been poorly explored. Results obtained to-date indicate that ENNs may confer an advantage to F. avenaceum only on particular hosts.

RESULTS

In this study, with the use of ENN-producing and ENN non-producing F. avenaceum strains, the role of ENNs on F. avenaceum virulence was investigated on the root, stem base and head of common wheat, and compared with the role of DON, using DON-producing and DON non-producing F. graminearum strains. The DON-producing F. graminearum strain showed a significantly higher ability to cause symptoms and colonise each of the tested tissues than the non-producing strain. On the other hand, the ability to produce ENNs increased initial symptoms of the disease and fungal biomass accumulation, measured by qPCR, only in wheat heads, and not in roots or stem bases. LC-MS/MS analysis was used to confirm the presence of ENNs and DON in the different strains, and results, both in vitro and in wheat heads, were consistent with the genetics of each strain.

CONCLUSION

While the key role of DON on F. graminearum virulence towards three different wheat tissues was noticeable, ENNs seemed to have a role only in influencing F. avenaceum virulence on common wheat heads probably due to an initial delay in the appearance of symptoms.

Characterization of the fludioxonil and phenamacril dual resistant mutants of Fusarium graminearum

Fusarium graminearum is an important fungal pathogen causing Fusarium head blight (FHB) in wheat and other cereal crops worldwide. Due to lack of resistant wheat cultivars, FHB control mainly relies on application of chemical fungicides. Both fludioxonil (a phenylpyrrole compound) and phenamacril (a cyanoacrylate fungicide) have been registered for controlling FHB in China, however, fludioxonil-resistant isolates of F. graminearum have been detected in field. To evaluate the potential risk of dual resistance of F. graminearum to both compounds, fludioxonil and phenamacril dual resistant (DR) mutants of F. graminearum were obtained via fungicide domestication in laboratory. Result showed that resistance of the DR mutants to both fludioxonil and phenamacril were genetically stable after sub-cultured for ten generations or stored at 4 °C for 30 days on fungicide-free PDA. Cross-resistance assay showed that the DR mutants remain sensitive to other groups of fungicides, including carbendazim, tebuconazole, pydiflumetofen, and fluazinam. In addition, the DR mutants exhibited defects in mycelia growth, conidiation, mycotoxin deoxynivalenol (DON) production, and virulence Moreover, the DR mutants displayed increased sensitivity to osmotic stress. Sequencing results showed that amino acid point mutations S217L/T in the myosin I protein is responsible for phenamacril resistance in the DR mutants. Our results indicate that mutations leading to fludioxonil and phenamacril dual resistance could result in fitness cost for F. graminearum. Our results also suggest that the potential risk of F. graminearum developing resistance to both fludioxonil and phenamacril in field could be rather low, which provides scientific guidance in controlling FHB with fludioxonil and phenamacril.

Mycotoxin occurrence in kernels and straws of wheat, barley, and tritordeum

Thirty-two varieties of common and durum wheat, hordeum, barley, and tritordeum collected over two harvesting years (2020 and 2021) were investigated for the presence of multiple Fusarium-related mycotoxins in asymptomatic plants. DON, 3-AcDON, 15-AcDON, T-2, HT-2, and ZEN together with the emerging mycotoxin ENN B and the major modified form of DON, namely DON3Glc, were quantified by means of UHPLC-MS/MS. Overall, DON and ENN B were the most frequently detected mycotoxins, albeit large inter-year variability was observed and related to different climate and weather conditions. Straws had higher mycotoxin contents than kernels and regarding DON occurrence tritordeum was found to be the most contaminated group on average for both harvesting years, while barley was the less contaminated one. Emerging mycotoxin ENN B showed comparable contents in kernels compared to straw, with a ratio close to 1 for tritordeum and barley. Regarding the occurrence of the other evaluated mycotoxins, T-2 and HT-2 toxins have been spotted in a few tritordeum samples, while ZEN has been frequently found only in straw from the harvesting year 2020. The data collected confirms the occurrence of multiple Fusarium mycotoxins in straws also from asymptomatic plants, highlighting concerns related to feed safety and animal health. The susceptibility of Tritordeum, hereby reported for the first time, suggests that careful measures in terms of monitoring, breeding, and cultural choices should be applied when dealing with his emerging crop.

Mycotoxin Determination and Occurrence in Pseudo-Cereals Intended for Food and Feed: A Review

Nowadays, pseudo-cereals' consumption is increasing due to their health benefits as they possess an excellent nutrient profile. Whole pseudo-cereal grains are rich in a wide range of compounds, namely flavonoids, phenolic acids, fatty acids, and vitamins with known beneficial effects on human and animal health. Mycotoxins are common contaminants in cereals and by-products; however, the study of their natural occurrence in pseudo-cereals is currently scarce. Pseudo-cereals are similar to cereal grains; thus, mycotoxin contamination is expected to occur in pseudo-cereals. Indeed, mycotoxin-producing fungi have been reported in these matrices and, consequently, mycotoxin contents have been reported too, especially in buckwheat samples, where ochratoxin A and deoxynivalenol reached levels up to 1.79 μg/kg and 580 μg/kg, respectively. In comparison to cereal contamination, mycotoxin levels detected in pseudo-cereal samples are lower; however, more studies are necessary in order to describe the mycotoxin pattern in these samples and to establish maximum levels that ensure human and animal health protection. In this review, mycotoxin occurrence in pseudo-cereal samples as well as the main extraction methods and analytical techniques to determine them are described, showing that mycotoxins can be present in pseudo-cereal samples and that the most employed techniques for their determination are liquid and gas chromatography coupled to different detectors.

Effects of climate change on the distribution of Fusarium spp. in Italy

This work studies the incidence of Fusarium spp. on wheat kernels about current and future climatic conditions in Italy. Epidemiological analyses were performed from 2007 to 2013 and the resulting dataset was used to find correlations between the disease incidence of five important Fusarium species monitored in Italy (Fusarium graminearum, F. langsethiae, F. sporotrichioides, F. poae and F. avenaceum) and climatic and geographical parameters. Probabilistic-based modelling of the actual distribution of Fusarium spp. was achieved by using the Zero-inflated Poisson regression. The probabilistic geographical distribution of the Fusarium species was assessed by applying future climatic scenarios (RCPs 4.5 and 8.5). The shift from current to future climatic scenarios highlighted changes on a national and regional scale. The tightening of environmental conditions from the RCP4.5 to 8.5 scenarios resulted in a sporadic presence of F. avenaceum only in the northern region of Italy. Fusarium graminearum was plentifully present in the current climate, but the tightening of minimum and maximum temperatures and the decrease of precipitation between May-June in the RCP8.5 no longer represents the optimum conditions for it. Fusarium langsethiae was currently distributed in all of Italy, showing an increase in the probability of detecting it by moving from high to low latitudes and from low to high longitudes in the RCP8.5. Fusarium poae, unlike other Fusarium species, grows and develops in arid climatic conditions. High values of F. poae were recorded at low latitudes and longitudes. Under the RCP scenarios, it showed high incidence probabilities in the southeast and northeast areas of Italy. Fusarium sporotrichioides is scarcely present in Italy, found at high latitudes and in the central areas. Climate change altered this distribution, and the chances of discovering it increased significantly moving to southern Italy. Overall, the study shows that climate change conditions are likely to lead to an increase in the incidence of Fusarium species on wheat kernels in Italy, highlighting the importance of developing strategies to mitigate the effects of climate change on wheat production, quality, and safety.

Impact of Enniatin and Deoxynivalenol Co-Occurrence on Plant, Microbial, Insect, Animal and Human Systems: Current Knowledge and Future Perspectives

Fusarium mycotoxins commonly contaminate agricultural products resulting in a serious threat to both animal and human health. The co-occurrence of different mycotoxins in the same cereal field is very common, so the risks as well as the functional and ecological effects of mycotoxins cannot always be predicted by focusing only on the effect of the single contaminants. Enniatins (ENNs) are among the most frequently detected emerging mycotoxins, while deoxynivalenol (DON) is probably the most common contaminant of cereal grains worldwide. The purpose of this review is to provide an overview of the simultaneous exposure to these mycotoxins, with emphasis on the combined effects in multiple organisms. Our literature analysis shows that just a few studies on ENN-DON toxicity are available, suggesting the complexity of mycotoxin interactions, which include synergistic, antagonistic, and additive effects. Both ENNs and DON modulate drug efflux transporters, therefore this specific ability deserves to be explored to better understand their complex biological role. Additionally, future studies should investigate the interaction mechanisms of mycotoxin co-occurrence on different model organisms, using concentrations closer to real exposures.

Dietary beauvericin and enniatin B exposure cause different adverse health effects in farmed Atlantic salmon

The extensive use of plant ingredients in novel aquafeeds have introduced mycotoxins to the farming of seafood. The emerging enniatin B (ENNB) and beauvericin (BEA) mycotoxins have been found in the novel aquafeeds and farmed fish. Little is known about the potential toxicity of ENNs and BEA in farmed fish and their feed-to-organ transfer. Atlantic salmon (Salmo salar) pre-smolt (75.3 ± 8.10 g) were fed four graded levels of spiked chemical pure ENNB or BEA feeds for three months, in triplicate tanks. Organismal adverse health end-point assessment included intestinal function (protein digestibility), disturbed hematology (red blood cell formation), bone formation (spinal deformity), overall energy use (feed utilization), and lipid oxidative status (vitamin E). Both dietary BEA and ENNB had a low (<∼0.01%) transfer to organs (kidney > liver > brain > muscle), with a higher transfer for ENNB compared to BEA. BEA caused a growth reduction combined with a decreased protein digestion and feed conversion rate- ENNB caused a stunted growth, unrelated to feed utilization capacity. In addition, ENNB caused anemia while BEA gave an oxidative stress response. Lower bench-mark dose regression assessment showed that high background levels of ENNB in commercial salmon feed could pose a risk for animal health, but not in the case of BEA.

Enniatin B and beauvericin affect intestinal cell function and hematological processes in Atlantic salmon (Salmo salar) after acute exposure

Unintentional use of mold-infested plant-based feed ingredients are sources of mycotoxins in fish feeds. The presence of the emerging mycotoxins ENNB and BEA in Norwegian commercial fish feeds and plant-based feed ingredients has raised concerns regarding the health effects on farmed Atlantic salmon (Salmon salar). Atlantic salmon pre-smolts were exposed to non-lethal doses of BEA and ENNB (ctrl, 50 and 500 μg/kg feed for 12 h), after which total RNA sequencing of the intestine and liver was carried out to evaluate gut health and identify possible hepatological changes after acute dietary exposure. ENNB and BEA did not trigger acute toxicity, however ENNB caused the onset of pathways linked to acute intestinal inflammation and BEA exposures caused the onset of hepatic hematological disruption. The prevalence and concentration of ENNB found in today's commercial feed could affect the fish health if consumed over a longer time-period.

Emerging health threat and cost of Fusarium mycotoxins in European wheat

Mycotoxins harm human and livestock health, while damaging economies. Here we reveal the changing threat of Fusarium head blight (FHB) mycotoxins in European wheat, using data from the European Food Safety Agency and agribusiness (BIOMIN, World Mycotoxin Survey) for ten years (2010-2019). We show persistent, high, single- and multi-mycotoxin contamination alongside changing temporal-geographical distributions, indicative of altering FHB disease pressure and pathogen populations, highlighting the potential synergistic negative health consequences and economic cost.

Infection timing affects Fusarium poae colonization of bread wheat spikes and mycotoxin accumulation in the grain

BACKGROUND

Fusarium poae is one of the most common Fusarium head blight (FHB) causal agents in wheat. This species can biosynthesize a wide range of mycotoxins, in particular nivalenol (NIV). In FHB epidemiology, infection timing is important for disease occurrence, kernel development, symptom appearance and mycotoxin accumulation in grain. The present study explored, both in a controlled environment and in a 2-year field plot experiment in Central Italy, the influence of five infection timings (from beginning of flowering to medium milk growth stage) on F. poae colonization and mycotoxin accumulation in bread wheat spikes (spring cv. A416 and winter cv. Ambrogio).

RESULTS

Both climate chamber and field experiments showed that early infection timings (from beginning of flowering to full flowering) especially favoured F. poae colonization and accumulation of its mycotoxins (particularly NIV) in grain. By contrast, later infection timings (watery ripe and medium milk) reduced F. poae development and mycotoxin levels. The time window of host susceptibility in the field was shorter than that observed under controlled conditions. Symptom expression in kernels also differed among infection timings. In general, F. poae biomass was higher in the chaff than in the grain.

CONCLUSION

These results enhance knowledge of a common member of the FHB complex worldwide, and could be useful in forecasting the risk of F. poae infection and mycotoxin contamination. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Temporal and spatial dynamics of Fusarium spp. and mycotoxins in Swedish cereals during 16 years

We analysed the dynamics of Fusarium spp. and mycotoxin contamination in Swedish cereals during 2004–2018. More than 1400 cereal samples from field trials were included, collected in a monitoring programme run by the Swedish Board of Agriculture. Five Fusarium mycotoxins were quantified with LC-MS/MS and fungal DNA from four species was quantified using quantitative real-time PCR. Correlation analyses revealed that deoxynivalenol (DON) and zearalenone (ZEN) were mainly associated with Fusarium graminearum, but stronger correlations with F. culmorum was seen some years. Nivalenol (NIV) was associated with F. poae and the HT-2 and T-2 toxins with F. langsethiae. Clear differences in mycotoxin contamination between different cereal crops and geographical regions were identified. The highest levels of DON and ZEN were found in spring wheat in Western Sweden. For NIV, HT-2 and T-2 toxins, the levels were highest in spring oats and spring barley. Regional differences were not detected for NIV, while HT-2 and T-2 toxins were associated with the northernmost region. We found that delayed harvest was strongly associated with increased levels of DON and ZEN in several crops. However, harvest date did not influence the levels of NIV or HT-2 and T-2 toxins. Our results suggest similar distribution patterns of DON and ZEN, in contrast to NIV and HT-2 and T-2 toxins, probably mirroring the differences in the ecology of the toxin-producing Fusarium species. Timely harvest is important to reduce the risk of DON and ZEN contamination, especially for fields with other risk factors.

Nivalenol Mycotoxin Concerns in Foods: An Overview on Occurrence, Impact on Human and Animal Health and Its Detection and Management Strategies

Mycotoxins are secondary metabolites produced by fungi that infect a wide range of foods worldwide. Nivalenol (NIV), a type B trichothecene produced by numerous Fusarium species, has the ability to infect a variety of foods both in the field and during post-harvest handling and management. NIV is frequently found in cereal and cereal-based goods, and its strong cytotoxicity poses major concerns for both human and animal health. To address these issues, this review briefly overviews the sources, occurrence, chemistry and biosynthesis of NIV. Additionally, a brief overview of several sophisticated detection and management techniques is included, along with the implications of processing and environmental factors on the formation of NIV. This review’s main goal is to offer trustworthy and current information on NIV as a mycotoxin concern in foods, with potential mitigation measures to assure food safety and security.

Toxicokinetics and metabolism of deoxynivalenol in animals and humans

Deoxynivalenol (DON) is the most widespread mycotoxin in food and feedstuffs, posing a persistent health threat to humans and farm animals. The susceptibilities of DON vary significantly among animals, following the order of pigs, mice/rats and poultry from the most to least susceptible. However, no study comprehensively disentangles factors shaping species-specific sensitivity. In this review, the toxicokinetics and metabolism of DON are summarized in animals and humans. Generally, DON is fast-absorbed and widely distributed in multiple organs. DON is first enriched in the plasma, liver and kidney and subsequently accumulates in the intestine. There are also key variations among animals. Pigs and humans are highly sensitive to DON, and they have similar absorption rates (1 h < t_max < 4 h), high bioavailability (> 55%) and long clearance time (2 h < t_1/2 < 4 h). Also, both species lack detoxification microorganisms and mainly depend on liver glucuronidation and urine excretion. Mice and rats have similar toxicokinetics (t_max < 0.5 h, t_1/2 < 1 h). However, a higher proportion of DON is excreted by feces as DOM-1 in rats than in mice, suggesting an important role of gut microbiota in rats. Poultry is least sensitive to DON due to their fast absorption rate (t_max < 1 h), low oral bioavailability (5-30%), broadly available detoxification gut microorganisms and short clearance time (t_1/2 < 1 h). Aquatic animals have significantly slower plasma clearance of DON than land animals. Overall, studies on toxicokinetics provide valuable information for risk assessment, prevention and control of DON contamination.

Distribution, pathogenicity and disease control of Fusarium tricinctum

Plant pathogenic fungi such as Fusarium tricinctum cause various plant diseases worldwide, especially in temperate regions. In cereals, F. tricinctum is one of the most common species causing Fusarium head blight (FHB) and root rot. Infection with F. tricinctum results in high yield losses and reduction in quality, mainly due to mycotoxin contamination of grain. Mycotoxins produced by F. tricinctum, such as enniatins (ENs) and moniliformin (MON), which are the most studied mycotoxins, have been reported to have multiple toxic effects on humans and animals. Although chemical control of Fusarium infection has been applied to grains, it is not always effective in controlling disease or reducing the level of mycotoxins in wheat grains. To the contrary, chemical control may significantly increase infection of F. tricinctum in fungicide-treated plots after treatment. Our studies show that the bacterium Bacillus amyloliquefaciens, has good control effects against F. tricinctum. Therefore, its use as a biological control agent against various plant pathogens may be an effective strategy to control the spread of Fusarium pathogens. Here, we conduct a review of the literature involving this plant pathogen, its diversity, virulence, and methods to control.

Roles of stress response-related signaling and its contribution to the toxicity of zearalenone in mammals

Zearalenone (ZEA) is a mycotoxin frequently found in cereal crops and cereal-derived foodstuffs worldwide. It affects plant productivity, and is also a serious hazard to humans and animals if being exposed to food/feed contaminated by ZEA. Studies over the last decade have shown that the toxicity of ZEA in animals is mainly mediated by the various stress responses, such as endoplasmic reticulum (ER) stress, oxidative stress, and others. Accumulating evidence shows that oxidative stress and ER stress signaling are actively implicated in and contributes to the pathophysiology of various diseases. Biochemically, the deleterious effects of ZEA are associated with apoptosis, DNA damage, and lipid peroxidation by regulating the expression of genes implicated in these biological processes. Despite these findings, the underlying mechanisms responsible for these alterations remain unclear. This review summarized the characteristics, metabolism, toxicity and the deleterious effects of ZEA exposure in various tissues of animals. Stress response signaling implicated in the toxicity as well as potential therapeutic options with the ability to reduce the deleterious effects of ZEA in animals were highlighted and discussed.

Deoxynivalenol: An Overview on Occurrence, Chemistry, Biosynthesis, Health Effects and Its Detection, Management, and Control Strategies in Food and Feed

Mycotoxins are fungi-produced secondary metabolites that can contaminate many foods eaten by humans and animals. Deoxynivalenol (DON), which is formed by Fusarium, is one of the most common occurring predominantly in cereal grains and thus poses a significant health risk. When DON is ingested, it can cause both acute and chronic toxicity. Acute signs include abdominal pain, anorexia, diarrhea, increased salivation, vomiting, and malaise. The most common effects of chronic DON exposure include changes in dietary efficacy, weight loss, and anorexia. This review provides a succinct overview of various sources, biosynthetic mechanisms, and genes governing DON production, along with its consequences on human and animal health. It also covers the effect of environmental factors on its production with potential detection, management, and control strategies.

Cytochrome P450 isoforms contribution, plasma protein binding, toxicokinetics of enniatin A in rats and in vivo clearance prediction in humans

Emerging mycotoxins, such as enniatin A (ENNA), are becoming a worldwide concern owing to their presence in different types of food and feed. However, comprehensive toxicokinetic data that links intake, exposure and toxicological effects of ENNA has not been elucidated yet. Therefore, the present study investigated the in vitro (rat and human) and in vivo (rat) toxicokinetic properties of ENNA. Towards this, an easily applicable and sensitive bioanalytical method was developed and validated for the estimation of ENNA in rat plasma. ENNA exhibited high plasma protein binding (99%), high hepatic clearance and mainly underwent metabolism via CYP3A4 (74%). The in-house predicted hepatic clearance (54 mL/min/kg) and observed in vivo rat clearance (55 mL/min/kg) were comparable. The predicted in vivo human hepatic clearance was 18 mL/min/kg. ENNA underwent slow absorption (T_max = 4 h) and rapid elimination following oral administration to rats. The absolute oral bioavailability was 47%. The toxicokinetic findings for ENNA from this study will help in designing and interpreting toxicological studies in rats. Besides, these findings could be used in physiologically based toxicokinetic (PBTK) model development for exposure predictions and risk assessment for ENNA in humans.

Beauvericin (BEA) and enniatin B (ENNB)-induced impairment of mitochondria and lysosomes - Potential sources of intracellular reactive iron triggering ferroptosis in Atlantic salmon primary hepatocytes

Beauvericin (BEA) and enniatin B (ENNB) are emerging mycotoxins frequently detected in plant-based fish feed. With ionophoric properties, they have shown cytotoxic potential in mammalian models. Sensitivity in fish is still largely unknown. Primary hepatocytes isolated from Atlantic salmon (Salmo salar) were used as a model and exposed to BEA and ENNB (0.05-10 μM) for 48 h. Microscopy, evaluation of cell viability, total ATP, total H₂O₂, total iron content, total Gpx enzyme activity, and RNA sequencing were used to characterize the toxicodynamics of BEA and ENNB. Both mycotoxins became cytotoxic at ≥ 5 μM, causing condensation of the hepatocytes followed by formation of blister-like protrusions on the cell's membrane. RNA sequencing analysis at sub-cytotoxic levels indicated BEA and ENNB exposed hepatocytes to experience increased energy expenditure, elevated oxidative stress, and iron homeostasis disturbances sensitizing the hepatocytes to ferroptosis. The present study provides valuable knowledge disclosing the toxic action of these mycotoxins in Atlantic salmon primary hepatocytes.

Effects of Fusarium metabolites beauvericin and enniatins alone or in mixture with deoxynivalenol on weaning piglets

The impact of the Fusarium-derived metabolites beauvericin, enniatin B and B1 (EB) alone or in combination with deoxynivalenol (DON) was investigated in 28-29 days old weaning piglets over a time period of 14 days. The co-application of EB and DON (EB + DON) led to a significant decrease in the weight gain of the animals. Liver enzyme activities in plasma were significantly decreased at day 14 in piglets receiving the EB + DON-containing diet compared to piglets receiving the control diet. All mycotoxin-contaminated diets led to moderate to severe histological lesions in the jejunum, the liver and lymph nodes. Shotgun metagenomics revealed a significant effect of EB-application on the gut microbiota. Our results provide novel insights into the harmful impact of emerging mycotoxins alone or with DON on the performance, gut health and immunological parameters in pigs.

Agronomic Factors Influencing the Scale of Fusarium Mycotoxin Contamination of Oats

Seven agronomic factors (crop season, farming system, harvest date, moisture, county, oat variety, and previous crop) were recorded for 202 oat crops grown across Ireland, and samples were analysed by LC-MS/MS for four major Fusarium mycotoxins: deoxynivalenol (DON), zearalenone (ZEN), T-2 toxin and HT-2 toxin. Type A trichothecenes were present in 62% of crops, with 7.4% exceeding European regulatory limits. DON (6.4%) and ZEN (9.9%) occurrences were relatively infrequent, though one and three samples were measured over their set limits, respectively. Overall, the type of farming system and the previous crop were the main factors identified as significantly influencing mycotoxin prevalence or concentration. Particularly, the adherence to an organic farming system and growing oats after a previous crop of grass were found to decrease contamination by type A trichothecenes. These are important findings and may provide valuable insights for many other types of cereal crops as Europe moves towards a much greater organic-based food system.

Multi-mycotoxin occurrence in feed, metabolism and carry-over to animal-derived food products: A review

The world requests for raw materials used in animal feed has been steadily rising in the last years driven by higher demands for livestock production. Mycotoxins are frequent toxic metabolites present in these raw materials. The exposure of farm animals to mycotoxins could result in undesirable residues in animal-derived food products. Thus, the potential ingestion of edible animal products (milk, meat and fish) contaminated with mycotoxins constitutes a public health concern, since they enter the food chain and may cause adverse effects upon human health. The present review summarizes the state-of-the-art on the occurrence of mycotoxins in feed, their metabolism and carry-over into animal source foodstuffs, focusing particularly on the last decade. Maximum levels (MLs) for various mycotoxins have been established for a number of raw feed materials and animal food products. Such values are sometimes exceeded, however. Aflatoxins (AFs), fumonisins (FBs), ochratoxin A (OTA), trichothecenes (TCs) and zearalenone (ZEN) are the most prevalent mycotoxins in animal feed, with aflatoxin M₁ (AFM1) predominating in milk and dairy products, and OTA in meat by-products. The co-occurrence of mycotoxins in feed raw materials tends to be the rule rather than the exception, and the carry-over of mycotoxins from feed to animal source foods is more than proven.

Modelling the Effects of Weather Conditions on Cereal Grain Contamination with Deoxynivalenol in the Baltic Sea Region

Fusarium head blight (FHB) is one of the most serious diseases of small-grain cereals worldwide, resulting in yield reduction and an accumulation of the mycotoxin deoxynivalenol (DON) in grain. Weather conditions are known to have a significant effect on the ability of fusaria to infect cereals and produce toxins. In the past 10 years, severe outbreaks of FHB, and grain DON contamination exceeding the EU health safety limits, have occurred in countries in the Baltic Sea region. In this study, extensive data from field trials in Sweden, Poland and Lithuania were analysed to identify the most crucial weather variables for the ability of Fusarium to produce DON. Models were developed for the prediction of DON contamination levels in harvested grain exceeding 200 µg kg⁻¹ for oats, spring barley and spring wheat in Sweden and winter wheat in Poland, and 1250 µg kg⁻¹ for spring wheat in Lithuania. These models were able to predict high DON levels with an accuracy of 70–81%. Relative humidity (RH) and precipitation (PREC) were identified as the weather factors with the greatest influence on DON accumulation in grain, with high RH and PREC around flowering and later in grain development and ripening correlated with high DON levels. High temperatures during grain development and senescence reduced the risk of DON accumulation. The performance of the models, based only on weather variables, was relatively accurate. In future studies, it might be of interest to determine whether inclusion of variables such as pre-crop, agronomic factors and crop resistance to FHB could further improve the performance of the models.

Enniatin B and Deoxynivalenol Activity on Bread Wheat and on Fusarium Species Development

Fusarium head blight (FHB) is a devastating wheat disease, mainly caused by Fusarium graminearum (FG)-a deoxynivalenol (DON)-producing species. However, Fusarium avenaceum (FA), able to biosynthesize enniatins (ENNs), has recently increased its relevance worldwide, often in co-occurrence with FG. While DON is a well-known mycotoxin, ENN activity, also in association with DON, is poorly understood. This study aims to explore enniatin B (ENB) activity, alone or combined with DON, on bread wheat and on Fusarium development. Pure ENB, DON, and ENB+DON (10 mg kg-1) were used to assess the impacts on seed germination, seedling growth, cell death induction (trypan blue staining), chlorophyll content, and oxidative stress induction (malondialdehyde quantification). The effect on FG and FA growth was tested using ENB, DON, and ENB+DON (10, 50, and 100 mg kg-1). Synergistic activity in the reduction of seed germination, growth, and chlorophyll degradation was observed. Conversely, antagonistic interaction in cell death and oxidative stress induction was found, with DON counteracting cellular stress produced by ENB. Fusarium species responded to mycotoxins in opposite directions. ENB inhibited FG development, while DON promoted FA growth. These results highlight the potential role of ENB in cell death control, as well as in fungal competition.

Occurrence, mitigation and in vitro cytotoxicity of nivalenol, a type B trichothecene mycotoxin - Updates from the last decade (2010-2020)

The present review aims to give an overview of the literature of the last decade (2010-2020) concerning the occurrence of the type B trichothecene mycotoxin nivalenol (NIV) and its in vitro toxicity, with the purpose of updating information regarding last researches on this mycotoxin. The most recent studies on the possible methods for preventing Fusarium spp. growth and NIV production are also discussed. Recently, various environmental factors have been shown to influence strongly NIV occurrence. However, Fusarium spp. of the NIV genotype have been found almost worldwide. With regard to NIV cytotoxicity, NIV has been reported to cause a marked decrease in cell proliferation in different mammalian cells. In particular, the recent data suggest that organs containing actively proliferating cells represent the main targets of NIV. Moreover, NIV resulted to cause immunosuppression, gastrointestinal toxicity and genotoxicity. However, sufficient evidence of carcinogenicity in humans is currently lacking, and the International Agency for Research on Cancer (IARC) classifies it as a group 3 carcinogen. Further researches and the discovery of effective treatment strategies to prevent NIV contamination and to counteract its toxicity are urgently required against this common food-borne threat to human health and livestock.

Mycotoxins in wheat cultivated in the Netherlands: results from eight years of field surveys

In the period 2009–2018, an annual field survey with commercial arable farms in the Netherlands was held, to collect data on agronomics of wheat fields as well as mycotoxin concentrations of the specific wheat field at harvest. In total, 293 full farm field records over 8 years were obtained. This study aimed to investigate (i) the occurrence of deoxynivalenol (DON) and other mycotoxins, as well as correlations between these mycotoxins, and (ii) the relationships between agronomics and the DON concentration in wheat kernels for wheat cultivated in the Netherlands. Results showed that mycotoxins most frequently observed in concentrations above the limit of quantification were DON, enniatin B and B₁, HT-2 toxin, zearalenone (ZEN) and nivalenol. On average, DON was detected in 54% of the samples (> 50 µg/kg) ranging from 19 to 92% depending on the year. Positive samples (> 50 µg/kg) had DON concentrations ranging 53–15,400 µg/kg, with a median of 228 µg/kg. Co-occurrence between DON and ZEN as well as between each of DON and ZEN with their modified forms was confirmed by the data of this study. The year influenced the DON concentration in wheat the most, followed by the region. The results of this study show that DON levels in wheat can only be influenced in a limited manner by agronomic practices such as the use of fungicides against Fusarium spp. around flowering, crop rotation, or the use of resistant wheat cultivars.

Occurrence, Impact on Agriculture, Human Health, and Management Strategies of Zearalenone in Food and Feed: A Review

Mycotoxins represent an assorted range of secondary fungal metabolites that extensively occur in numerous food and feed ingredients at any stage during pre- and post-harvest conditions. Zearalenone (ZEN), a mycotoxin categorized as a xenoestrogen poses structural similarity with natural estrogens that enables its binding to the estrogen receptors leading to hormonal misbalance and numerous reproductive diseases. ZEN is mainly found in crops belonging to temperate regions, primarily in maize and other cereal crops that form an important part of various food and feed. Because of the significant adverse effects of ZEN on both human and animal, there is an alarming need for effective detection, mitigation, and management strategies to assure food and feed safety and security. The present review tends to provide an updated overview of the different sources, occurrence and biosynthetic mechanisms of ZEN in various food and feed. It also provides insight to its harmful effects on human health and agriculture along with its effective detection, management, and control strategies.

Feedborne Mycotoxins Beauvericin and Enniatins and Livestock Animals

Mycotoxins are secondary metabolites produced by several species of fungi, including the Fusarium, Aspergillus, and Penicillium species. Currently, more than 300 structurally diverse mycotoxins are known, including a group called minor mycotoxins, namely enniatins, beauvericin, and fusaproliferin. Beauvericin and enniatins possess a variety of biological activities. Their antimicrobial, antibiotic, or ionoforic activities have been proven and according to various bioassays, they are believed to be toxic. They are mainly found in cereal grains and their products, but they have also been detected in forage feedstuff. Mycotoxins in feedstuffs of livestock animals are of dual concern. First one relates to the safety of animal-derived food. Based on the available data, the carry-over of minor mycotoxins from feed to edible animal tissues is possible. The second concern relates to detrimental effects of mycotoxins on animal health and performance. This review aims to summarize current knowledge on the relation of minor mycotoxins to livestock animals.

Fusarium Mycotoxins in Two Hulless Oat and Barley Cultivars Used for Food Purposes

Hulless oats and hulless barley are highly valued for their excellent nutritional attributes and are increasingly being promoted in human nutrition. However, special attention should be paid to the risk of their contamination by Fusarium mycotoxins, as the rate of mycotoxin reduction during processing could be much lower than that for hulled cereals. In the present study, mycotoxin contamination of two cultivars, each of hulless oats and barley suitable for food purposes were studied in a 3-year field trial established in two contrasting environments. The contents of the mycotoxins regulated by law (deoxynivalenol and zearalenone) were low, and the present legal limits for their maximum content in unprocessed cereals were far from being exceeded. The mycotoxins most frequently occurring in hulless barley were enniatins (enniatin B, enniatin B₁ and enniatin A₁), beauvericin and nivalenol; hulless oats most frequently contained the HT-2 and T-2 toxins, beauvericin and enniatin B. The contents of enniatins and nivalenol were higher in barley than in oats. Close, positive relationships between the contents of the individual enniatins and between enniatins, beauvericin and nivalenol were observed, which implies that co-exposure could enhance the toxic potential of these mycotoxins through synergistic effects. The results highlight the need to pay more attention to the occurrence of enniatins, beauvericine and nivalenol in hulless oats and barley used for food purposes.

A novel metabarcoding approach to investigate Fusarium species composition in soil and plant samples

The genus Fusarium contains more than 300 species, most of which are plant pathogens. Appropriate molecular tools for accurately and rapidly describing temporal and spatial shifts in Fusarium communities would be useful for the development of control strategies. Here, we present a new Fusarium-specific primer pair targeting the translation elongation factor 1-α (EF1α) gene with amplicons of ~430 bp, suitable for MiSeq metabarcoding sequencing. Mock Fusarium communities were used to evaluate its resolution and to optimize read filtering and downstream analyses. The use of the DADA2 pipeline coupled with operational taxonomic unit (OTU) picking at 98% similarity cut-off significantly increased the accuracy of read filtering. Building a phylogenetic tree using a manually curated database as a reference allowed taxonomic assignment at the species or species-complex level. This methodology was tested on soil and maize residue samples collected from crop fields. Up to 18 Fusarium OTUs, belonging to 17 species and 8 species complexes, were obtained, with F. oxysporum being the most abundant species in soil samples, while F. graminearum and F. avenaceum were the most abundant in maize residues. We demonstrated the high performance of this workflow which could be further used for profiling Fusarium species composition and dynamics during the cultivation cycle.

Removal of Small Kernels Reduces the Content of Fusarium Mycotoxins in Oat Grain

Cereal grain contaminated by Fusarium mycotoxins is undesirable in food and feed because of the harmful health effects of the mycotoxins in humans and animals. Reduction of mycotoxin content in grain by cleaning and size sorting has mainly been studied in wheat. We investigated whether the removal of small kernels by size sorting could be a method to reduce the content of mycotoxins in oat grain. Samples from 24 Norwegian mycotoxin-contaminated grain lots (14 from 2015 and 10 from 2018) were sorted by a laboratory sieve (sieve size 2.2 mm) into large and small kernel fractions and, in addition to unsorted grain samples, analyzed with LC-MS-MS for quantification of 10 mycotoxins. By removing the small kernel fraction (on average 15% and 21% of the weight of the samples from the two years, respectively), the mean concentrations of HT-2+T-2 toxins were reduced by 56% (from 745 to 328 µg/kg) in the 2015 samples and by 32% (from 178 to 121 µg/kg) in the 2018 samples. Deoxynivalenol (DON) was reduced by 24% (from 191 to 145 µg/kg) in the 2018 samples, and enniatin B (EnnB) by 44% (from 1059 to 594 µg/kg) in the 2015 samples. Despite low levels, our analyses showed a trend towards reduced content of DON, ADON, NIV, EnnA, EnnA1, EnnB1 and BEA after removing the small kernel fraction in samples from 2015. For several of the mycotoxins, the concentrations were considerably higher in the small kernel fraction compared to unsorted grain. Our results demonstrate that the level of mycotoxins in unprocessed oat grain can be reduced by removing small kernels. We assume that our study is the first report on the effect of size sorting on the content of enniatins (Enns), NIV and BEA in oat grains.

Fusarium Mycotoxins Enniatins: An Updated Review of Their Occurrence, the Producing Fusarium Species, and the Abiotic Determinants of Their Accumulation in Crop Harvests

Cereal grains and their processed food products are frequently contaminated with mycotoxins produced by the Fusarium genus. Enniatins (ENNs), which belong to the so-called "emerging mycotoxins" family, are among the most frequently found in small grain cereals. Health hazards induced by a chronic exposure to ENNs or an association of ENNs with other major mycotoxins is a risk that cannot be excluded given the current toxicological data. Thus, efforts must be pursued to define efficient control strategies to mitigate their presence in cereal grains. A key condition for achieving this aim is to gain deep and comprehensive knowledge of the factors promoting the appearance of ENNs in crop harvests. After an update of ENN occurrence data, this review surveys the scientific literature on the Fusarium species responsible for ENN contamination and covers the recent advances concerning the abiotic determinants and the genetic regulation of ENN biosynthesis.

Composition and Predominance of Fusarium Species Causing Fusarium Head Blight in Winter Wheat Grain Depending on Cultivar Susceptibility and Meteorological Factors

Fusarium head blight (FHB) is one of the most important diseases of wheat, causing yield losses and mycotoxin contamination of harvested grain. A complex of different toxigenic Fusarium species is responsible for FHB and the composition and predominance of species within the FHB complex are determined by meteorological and agronomic factors. In this study, grain of three different susceptible winter wheat cultivars from seven locations in northern Germany were analysed within a five-year survey from 2013 to 2017 by quantifying DNA amounts of different species within the Fusarium community as well as deoxynivalenol (DON) and zearalenone (ZEA) concentrations. Several Fusarium species co-occur in wheat grain samples in all years and cultivars. F. graminearum was the most prevalent species, followed by F. culmorum, F. avenaceum and F. poae, while F. tricinctum and F. langsethiae played only a subordinate role in the FHB complex in terms of DNA amounts. In all cultivars, a comparable year-specific quantitative occurrence of the six detected species and mycotoxin concentrations were found, but with decreased DNA amounts and mycotoxin concentrations in the more tolerant cultivars, especially in years with higher disease pressure. In all years, similar percentages of DNA amounts of the six species to the total Fusarium DNA amount of all detected species were found between the three cultivars for each species, with F. graminearum being the most dominant species. Differences in DNA amounts and DON and ZEA concentrations between growing seasons depended mainly on moisture factors during flowering of wheat, while high precipitation and relative humidity were the crucial meteorological factors for infection of wheat grain by Fusarium. Highly positive correlations were found between the meteorological variables precipitation and relative humidity and DNA amounts of F. graminearum, DON and ZEA concentrations during flowering, whereas the corresponding correlations were much weaker several days before (heading) and after flowering (early and late milk stage).

Regional and field-specific differences in Fusarium species and mycotoxins associated with blighted North Carolina wheat

Worldwide, while Fusarium graminearum is the main causal species of Fusarium head blight (FHB) in small-grain cereals, a diversity of FHB-causing species belonging to different species complexes has been found in most countries. In the U.S., FHB surveys have focused on the Fusarium graminearum species complex (FGSC) and the frequencies of 3-ADON, 15-ADON, and nivalenol (NIV) chemotypes. A large-scale survey was undertaken across the state of North Carolina in 2014 to explore the frequency and distribution of F. graminearum capable of producing NIV, which is not monitored at grain intake points. Symptomatic wheat spikes were sampled from 59 wheat fields in 24 counties located in three agronomic zones typical of several states east of the Appalachian Mountains: Piedmont, Coastal Plain, and Tidewater. Altogether, 2197 isolates were identified to species using DNA sequence-based methods. Surprisingly, although F. graminearum was the majority species detected, species in the Fusarium tricinctum species complex (FTSC) that produce "emerging mycotoxins" were frequent, and even dominant in some fields. The FTSC percentage was 50-100% in four fields, 30-49% in five fields, 20-29% in five fields, and < 20% in the remaining 45 fields. FTSC species were at significantly higher frequency in the Coastal Plain than in the Piedmont or Tidewater (P < .05). Moniliformin concentrations in samples ranged from 0.0 to 38.7 μg g^-1. NIV producing isolates were rare statewide (2.2%), and never >12% in a single field, indicating that routine testing for NIV is probably unnecessary. The patchy distribution of FTSC species in wheat crops demonstrated the need to investigate the potential importance of their mycotoxins and the factors that allow them to sometimes outcompete trichothecene producers. An increased sampling intensity of wheat fields led to the unexpected discovery of a minority FHB-causing population.

Occurrence and preventive strategies to control mycotoxins in cereal-based food

Mycotoxins contamination in cereal-based food is ubiquitous according to systematic review of the scientific documentation of worldwide mycotoxin contamination in cereal and their products between 2008 and 2018, thus representing food safety issue especially in developing tropical countries. Food processing plays a vital role to prevent mycotoxin contamination in food. Therefore, it is with great urgency to develop strategies to inhibit fungi growth and mycotoxin production during food processing. This review begins by discussing physicochemical properties of five most common mycotoxins (aflatoxins, fumonisins, ochratoxins, deoxynivalenol, and zearalenone) found in cereal grains, regulation for mycotoxins in food, and their potential negative impact on human health. The fate of mycotoxins during major cereal-based food processing including milling, breadmaking, extrusion, malting, and brewing was then summarized. In the end, traditional mitigation strategies including physical and chemical and potential application of biocontrol agent and essential oil nanoemulsions that can be applied during food processing were discussed. It indicated that no single method is currently available to completely prevent mycotoxin contamination in cereal foods.

Cultivation Area Affects the Presence of Fungal Communities and Secondary Metabolites in Italian Durum Wheat Grains

In this study, durum wheat kernels harvested in three climatically different Italian cultivation areas (Emilia Romagna, Umbria and Sardinia) in 2015, were analyzed with a combination of different isolation methods to determine their fungal communities, with a focus on Fusarium head blight (FHB) complex composition, and to detect fungal secondary metabolites in the grains. The genus Alternaria was the main component of durum wheat mycobiota in all investigated regions, with the Central Italian cultivation area showing the highest incidence of this fungal genus and of its secondary metabolites. Fusarium was the second most prevalent genus of the fungal community in all cultivation environments, even if regional differences in species composition were detected. In particular, Northern areas showed the highest Fusarium incidence, followed by Central and then Southern cultivation areas. Focusing on the FHB complex, a predominance of Fusariumpoae, in particular in Northern and Central cultivation areas, was found. Fusariumgraminearum, in the analyzed year, was mainly detected in Emilia Romagna. Because of the highest Fusarium incidence, durum wheat harvested in the Northern cultivation area showed the highest presence of Fusarium secondary metabolites. These results show that durum wheat cultivated in Northern Italy may be subject to a higher FHB infection risk and to Fusarium mycotoxins accumulation.

Investigating the in vitro catabolic fate of Enniatin B in a human gastrointestinal and colonic model

Enniatin B is an emerging mycotoxin known to present biological activity because of its ionophoric characteristics. This compound has demonstrated strong in vitro cytotoxicity against different cancer cells, also at low molecular concentrations. Its natural occurrence in food commodities and feed is highly reported world-wide, but few information is available about its stability in the human gastro-intestinal tract. The present work evaluates the catabolic fate of enniatin B upon in vitro simulated digestion and colonic fermentation. LC-MS target and untargeted analysis have been performed to quantify the extent of enniatin B degradation and the formation of catabolic products. The results obtained showed significant degradation of enniatin B (degradation rate 79 ± 5%) along the gastrointestinal tract and further degradation of residual enniatin B was observed during colonic fermentation after 24 h of incubation. Moreover, 5 catabolic metabolites of enniatin B were putatively identified after gastrointestinal digestion resulting from the oxidation and opening of the depsipeptide ring. As a final step, the pharmacokinetic properties of enniatin B degradation products were tested in silico revealing that some of them may be adsorbed at the gastrointestinal level more than the parent compound. Additionally, the smaller degradation products showed moderate blood-brain-barrier crossing.

Risk assessment for mycotoxin contamination in fish feeds in Europe

Mycotoxins are difficult to monitor continuously, and a tool to assess the risk would help to judge if there is a particular risk due to the inclusion of certain feed ingredients. For this, the toxin contents of 97 commercial fish feeds have been estimated, and the most prominent toxins in fish feed are calculated to be deoxynivalenol, zearalenone, fumonisins and enniatins. These pose a risk to fish well-being, as can be calculated by the Bayesian models for determining the critical concentrations 5% (CC5) for the different toxins. Besides fishmeal, wheat, soybean products and corn are regularly used as fish feed ingredients. The calculated scenarios show that fish are at high risk of toxin contamination if feed ingredients of low quality are chosen for feed production. Due to this, specific maximum allowable levels for several mycotoxins in fish feeds should be established.

Effects of Fusarium graminearum and Fusarium poae on disease parameters, grain quality and mycotoxins contamination in bread wheat (Part I)

BACKGROUND

Wheat is the most important winter crop in the world, being affected by the presence of fungal, mainly those belonging to the Fusarium genus. Fusarium head blight (FHB) is a serious disease that causes important economic damage and quantitative/qualitative losses, with Fusarium graminearum and Fusarium poae being two of the most isolated species worldwide. The present study aimed to evaluate the interaction between F. graminearum and F. poae and the effects on disease parameters, grain quality and mycotoxin contamination on five wheat genotypes under field conditions during three growing seasons.

RESULTS

Statistical differences between Fusarium treatments were found for disease parameters, grain quality and mycotoxin contamination during the 2014/2015 growing season. High values of incidence (58.00 ± 8.00%), severity (6.28 ± 1.51%) and FHB index (4.72 ± 1.35) were observed for F. graminearum + F. poae treatment. Regarding grain quality, the results showed that the degradation of different protein fractions depends on each Fusarium species: glutenins were degraded preferably by F. graminearum (-70.82%), gliadins were degraded preferably by F. poae (-29.42%), whereas both protein fractions were degraded when both Fusarium species were present (-60.91% and -16.51%, respectively). Significant differences were observed for mycotoxin contamination between genotypes, with Proteo being the most affected (DON = 12.01 ± 3.67 μg g^-1 ). In addition, we report that 3-ADON predominated over 15-ADON in the three seasons evaluated.

CONCLUSION

Variations in plant-pathogen interaction (Fusarium-wheat pathosystem) should be considered at least in years with favorable climatic conditions for FHB development, as a result of the potential impact of this disease on grain quality and mycotoxin contamination. © 2019 Society of Chemical Industry.

Twenty-Eight Fungal Secondary Metabolites Detected in Pig Feed Samples: Their Occurrence, Relevance and Cytotoxic Effects In Vitro

Feed samples are frequently contaminated by a wide range of chemically diverse natural products, which can be determined using highly sensitive analytical techniques. Next to already well-investigated mycotoxins, unknown or unregulated fungal secondary metabolites have also been found, some of which at significant concentrations. In our study, 1141 pig feed samples were analyzed for more than 800 secondary fungal metabolites using the same LC-MS/MS method and ranked according to their prevalence. Effects on the viability of the 28 most relevant were tested on an intestinal porcine epithelial cell line (IPEC-J2). The most frequently occurring compounds were determined as being cyclo-(L-Pro-L-Tyr), moniliformin, and enniatin B, followed by enniatin B1, aurofusarin, culmorin, and enniatin A1. The main mycotoxins, deoxynivalenol and zearalenone, were found only at ranks 8 and 10. Regarding cytotoxicity, apicidin, gliotoxin, bikaverin, and beauvericin led to lower IC50 values, between 0.52 and 2.43 µM, compared to deoxynivalenol (IC50 = 2.55 µM). Significant cytotoxic effects were also seen for the group of enniatins, which occurred in up to 82.2% of the feed samples. Our study gives an overall insight into the amount of fungal secondary metabolites found in pig feed samples compared to their cytotoxic effects in vitro.

Plant-based milks: unexplored source of emerging mycotoxins. A proposal for the control of enniatins and beauvericin using UHPLC-MS/MS

Mycotoxins have become one of the most common contaminants reported worldwide. Current legislation has established maximum levels only for some well-known mycotoxins; however, there are many other "emerging mycotoxins" for which there is no regulation, as enniatins and beauvericin. An analytical method based on salting-out assisted liquid-liquid extraction followed by ultra-high performance liquid chromatography tandem mass spectrometry is proposed for determination of enniatin A, A1, B, B1, and beauvericin in different plant-based milks, as a possible source of these contaminants, is proposed. The method showed good precision and trueness (RSD <8% and recoveries between 84-97%) with a moderate matrix effect. From a total of 32 samples of plant-based milks of different compositions (including 8 rice milks, 8 oat milks and 16 soy milks), 3 samples were contaminated with the five mycotoxins, while 5 samples were contaminated with four of them, being oat milk the most susceptible for contamination.

Pig Urinary Concentration of Mycotoxins and Metabolites Reflects Regional Differences, Mycotoxin Intake and Feed Contaminations

The determination of mycotoxin and metabolite concentrations in human and animal urine is currently used for risk assessment and mycotoxin intake measurement. In this study, pig urine (n = 195) was collected at slaughterhouses in 2012 by the Swedish National Food Agency in three counties representing East, South and West regions of Sweden. Urinary concentrations of four mycotoxins, (deoxynivalenol (DON), zearalenone (ZEA), fumonisin B1 (FB1), and ochratoxin A (OTA)), and four key metabolites, (deepoxy-deoxynivalenol (DOM-1), aflatoxin M1 (AFM1, biomarker of AFB1), α-zearalenol (α-ZOL), and β-zearalenol (β-ZOL)) were identified and measured by UPLC-MS/MS. Statistically significant regional differences were detected for both total DON (DON + DOM-1) and total ZEA (ZEA + α-ZOL + β-ZOL) concentrations in pig urine from the three regions. These regional differences were in good agreement with the occurrence of Fusarium graminearum mycotoxins (DON + ZEA) in cereal grains harvested in 2011 in Sweden. There were no statistically significant differences in FB1, AFM1 and OTA urinary concentrations in pigs from the three regions. The overall incidence of positive samples was high for total ZEA (99-100%), total DON (96-100%) and OTA (85-95%), medium for FB1 (30-61%) and low for AFM1 (0-13%) in the three regions. Urinary mycotoxin biomarker concentrations were used to estimate mycotoxin intake and the level of mycotoxins in feeds consumed by the monitored pigs. The back-calculated levels of mycotoxins in feeds were low with the exception of seven samples that were higher the European limits.