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Mycotoxins are toxic secondary metabolites of fungi that grow on food and feed matrices and significantly harm the health of humans and farm animals. Among the reported mycotoxigenic fungi, Fusarium graminearum has received wide attention due to its ability to produce multiple mycotoxins, including deoxynivalenol (DON), nivalenol (NIV), and zearalenone (ZEA) under diverse climatic conditions. The present study focused on proving in vitro cytotoxicity of F. graminearum toxins (DON, NIV, and ZEA) in H9c2 cells (Rattus norvegicus heart/myocardi). The effect of F. graminearum toxins (FGTs) on cell viability was studied by MTT, LDH, and live/dead cell assays. The cell viability decreased with increasing the quantity of FGTs and was noticed as dose-dependent. The cell viability assays indicated that DON was significantly more toxic than NIV, and both were considerably more toxic than ZEA. The toxicity mechanism of FGTs was revealed by estimating reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and caspase-3 levels. The effect of FGTs on the generation of ROS was observed by fluorescent probe dichloro-dihydro-fluorescein diacetate (DCFH-DA), and the ROS levels were enhanced on the treatment of FGTs. The effect of FGTs on MMP was revealed by rhodamine 123 staining, and MMP levels were depleted with exposure to FGTs. Furthermore, the expression level of caspase-3 was determined by a caspase-3 detection kit, and its levels were enhanced by exposure to FGTs. The studies conclude that FGTs have a potent cytotoxic effect on H9c2 cells and induce death by oxidative stress-mediated apoptosis. [ABSTRACT FROM AUTHOR]

Currently, the EU is focusing on less intensive agrotechnology and sustainable development. It is important to minimize the occurrence of mycotoxins (including Fusariotixins) in food, and to monitor mycotoxin concentration in the food chain. Therefore, this study evaluated Fusarium mycotoxin contamination, specifically type A and B trichothecenes and ergosterol concentration, in wheat grain from a three-year field experiment (2019–2021) conducted at IUNG-PIB in Osiny (Poland), along with its byproducts (bran, flour, bread). Four wheat cultivars were grown under different farming systems: organic (ORG), integrated (INT), and conventional (CONV). Ergosterol was analyzed using HPLC with an absorbance detector while Type A and B trichothecenes were analyzed using gas chromatography and mass spectrometry. Results showed that the farming system significantly influenced type B trichothecenes concentration in grain, with the highest concentration established in ORG-grown wheat. However, the grain concentration from the INT farming system was comparable to that from CONV. Type A trichothecenes concentrations were low and not significantly affected by the farming system. Bran exhibited the highest ergosterol and mycotoxin concentration, while flour and bread exhibited the lowest. [ABSTRACT FROM AUTHOR]

This study investigated the immunotoxic effects of the mycotoxin nivalenol (NIV) using antigen-presenting cells and a mouse model of atopic dermatitis (AD). In vitro experiments were conducted using a mouse macrophage cell line (RAW 264.7) and mouse dendritic cell line (DC 2.4). After cells were exposed to NIV (0.19–5 µmol) for 24 h, the production of pro-inflammatory cytokines (IL-1β, IL-6, and TNFα) was quantified. To further investigate the inflammatory cytokine production pathway, the possible involvement of mitogen-activated protein kinase (MAPK) pathways, such as ERK1/2, p-38, and JNK, in NIV exposure was analyzed using MAPK inhibitors and phosphorylation analyses. In addition, the pro-inflammatory effects of oral exposure to NIV at low concentrations (1 or 5 ppm) were evaluated in an NC/Nga mouse model of hapten-induced AD. In vitro experiments demonstrated that exposure to NIV significantly enhanced the production of TNFα. In addition, it also directly induced the phosphorylation of MAPK, indicated by the inhibition of TNFα production following pretreatment with MAPK inhibitors. Oral exposure to NIV significantly exacerbated the symptoms of AD, including a significant increase in helper T cells and IgE-produced B cells in auricular lymph nodes and secretion of pro-inflammatory cytokines, such as IL-4, IL-5, and IL-13, compared with the vehicle control group. Our findings indicate that exposure to NIV directly enhanced the phosphorylation of ERK1/2, p-38, and JNK, resulting in a significant increase in TNFα production in antigen-presenting cells, which is closely related to the development of atopic dermatitis. [ABSTRACT FROM AUTHOR]

This study reports levels of mycotoxins in sorghum from Niger State, Nigeria, and provides a comprehensive assessment of their potential health risks by combining mycotoxin levels and dietary exposure assessment. A total of 240 samples of red and white sorghum were collected from both stores and markets across four microclimatic zones. Fungal species were identified using a dilution plate method. Aflatoxins (AFs), deoxynivalenol, nivalenol, and ochratoxin (OTA) were quantified using HPLC, whereas cyclopiazonic acid, fumonisins (FUMs) and zearalenone were quantified using ELISA. A. flavus and A. fumigatus were dominant fungal species followed by F. verticilloides, A. oryzae and P. verrucosum. Aflatoxins (mean: 29.97 µg/kg) were detected in all samples, whereas OTA (mean: 37.5 µg/kg) and FUMs (mean: 3269.8 µg/kg) were detected in 72% and 50% of the samples, respectively. Mycotoxins frequently co-occurred in binary mixtures of AFs + OTA and AFs + FUMs. Dietary exposure estimates were highest for FUMs at 230% of TDI and margin of exposures (MOEs) for both AFs and OTA (<10,000) indicating a potential risk associated with combined exposure to AFs and OTA. The Risk of hepatocellular carcinoma cases (HCC/year) attributable to AFs and OTA exposure from sorghum was estimated to be 5.99 × 105 and 0.24 × 105 cases for HBsAg + individuals based on 13.6% HBV incidence. Similarly, the HCC/year for AFs and OTA were assessed to be 3.59 × 105 and 0.14 × 105 at an 8.1% prevalence rate. Therefore, the results of this study demonstrate the high prevalence and dietary exposure to mycotoxins through sorghum consumption, raising public health and trade concerns. [ABSTRACT FROM AUTHOR]

Fusarium species are cosmopolitan soil phytopathogens from the division Ascomycota, which produce mycotoxins and cause significant economic losses of crop plants. However, soils suppressive to Fusarium diseases are known to occur, and recent knowledge on microbial diversity in these soils has shed new lights on phytoprotection effects. In this review, we synthesize current knowledge on soils suppressive to Fusarium diseases and the role of their rhizosphere microbiota in phytoprotection. This is an important issue, as disease does not develop significantly in suppressive soils even though pathogenic Fusarium and susceptible host plant are present, and weather conditions are suitable for disease. Soils suppressive to Fusarium diseases are documented in different regions of the world. They contain biocontrol microorganisms, which act by inducing plants’ resistance to the pathogen, competing with or inhibiting the pathogen, or parasitizing the pathogen. In particular, some of the Bacillus, Pseudomonas, Paenibacillus and Streptomyces species are involved in plant protection from Fusarium diseases. Besides specific bacterial populations involved in disease suppression, next-generation sequencing and ecological networks have largely contributed to the understanding of microbial communities in soils suppressive or not to Fusarium diseases, revealing different microbial community patterns and differences for a notable number of taxa, according to the Fusarium pathosystem, the host plant and the origin of the soil. Agricultural practices can significantly influence soil suppressiveness to Fusarium diseases by influencing soil microbiota ecology. Research on microbial modes of action and diversity in suppressive soils should help guide the development of effective farming practices for Fusarium disease management in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Fusarium species are cosmopolitan soil phytopathogens from the division Ascomycota, which produce mycotoxins and cause significant economic losses of crop plants. However, soils suppressive to Fusarium diseases are known to occur, and recent knowledge on microbial diversity in these soils has shed new lights on phytoprotection effects. In this review, we synthesize current knowledge on soils suppressive to Fusarium diseases and the role of their rhizosphere microbiota in phytoprotection. This is an important issue, as disease does not develop significantly in suppressive soils even though pathogenic Fusarium and susceptible host plant are present, and weather conditions are suitable for disease. Soils suppressive to Fusarium diseases are documented in different regions of the world. They contain biocontrol microorganisms, which act by inducing plants’ resistance to the pathogen, competing with or inhibiting the pathogen, or parasitizing the pathogen. In particular, some of the Bacillus, Pseudomonas, Paenibacillus and Streptomyces species are involved in plant protection from Fusarium diseases. Besides specific bacterial populations involved in disease suppression, next-generation sequencing and ecological networks have largely contributed to the understanding of microbial communities in soils suppressive or not to Fusarium diseases, revealing different microbial community patterns and differences for a notable number of taxa, according to the Fusarium pathosystem, the host plant and the origin of the soil. Agricultural practices can significantly influence soil suppressiveness to Fusarium diseases by influencing soil microbiota ecology. Research on microbial modes of action and diversity in suppressive soils should help guide the development of effective farming practices for Fusarium disease management in sustainable agriculture.

Fusarium graminearum (FG) and Fusarium verticillioides (FV) co-occur in infected plants and plant residues. In maize ears, the growth of FV is stimulated while FG is suppressed. To elucidate the role of mycotoxins in these effects, we used FG mutants with disrupted synthesis of nivalenol (NIV) and deoxynivalenol (DON) and a FV mutant with disrupted synthesis of fumonisins to monitor fungal growth in mixed cultures in vitro and in co-infected plants by real-time PCR. In autoclaved grains as well as in maize ears, the growth of FV was stimulated by FG regardless of the production of DON or NIV by the latter, whereas the growth of FG was suppressed. In autoclaved grains, fumonisin-producing FV suppressed FG more strongly than a fumonisin-nonproducing strain, indicating that fumonisins act as interference competition agents. In co-infected maize ears, FG suppression was independent of fumonisin production by FV, likely due to heterogeneous infection and a lower level of fumonisins in planta. We conclude that (i) fumonisins are agents of interference competition of FV, and (ii) trichothecenes play no role in the interaction between FG and FV. We hypothesize the following: (i) In vitro, FG stimulates the FV growth by secreting hydrolases that mobilize nutrients. In planta, suppression of plant defense by FG may additionally play a role. (ii) The biological function of fumonisin production in planta is to protect kernels shed on the ground by accumulating protective metabolites before competitors become established. Therefore, to decipher the biological function of mycotoxins, the entire life history of mycotoxin producers must be considered. [ABSTRACT FROM AUTHOR]

Fusarium cerealis is a causal agent of Fusarium Head Blight in wheat, and it produces both deoxynivalenol (DON) and nivalenol (NIV). Nevertheless, the effect of environmental factors on the growth and mycotoxin production of this species has not been studied so far. The objective of this study was to investigate the impact of environmental factors on the growth and mycotoxin production of F. cerealis strains. All strains were able to grow in a wide range of water activity (aW) and temperatures, but their mycotoxin production was influenced by strain and environmental factors. NIV was produced at high aW and temperatures, while optimal conditions for DON production were observed at low aW. Interestingly, some strains were able to simultaneously produce both toxins, which could pose a more significant risk for grain contamination. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Nivalenol (NIV) is a trichothecene mycotoxin that is more toxic than deoxynivalenol. It accumulates in grains due to infection with Fusarium species, which are the causative agents of scab or Fusarium head blight. An immunoassay, which is a rapid and easy analytical method, is necessary for monitoring NIV in grains. However, a specific antibody against NIV has not been prepared previously. To establish an immunoassay, we prepared NIV, introduced a linker, and generated antibodies against it. NIV was prepared from a culture of Fusarium kyushuense obtained from pressed barley through chromatographic procedures with synthetic adsorbents and silica gel. NIV was reacted with glutaric anhydride, and the reaction was stopped before mono-hemiglutaryl-NIV was changed to di-hemiglutaryl-NIV. 15-O-Hemiglutaryl-NIV was isolated via preparative HPLC and bound to keyhole limpet hemocyanin (KLH) using the active ester method. Two different monoclonal antibodies were prepared by immunizing mice with the NIV-KLH conjugate. The 50% inhibitory concentration values were 36 and 37 ng/mL. These antibodies also showed high reactivity in a direct competitive enzyme-linked immunosorbent assay and specifically reacted with NIV and 15-acetyl-NIV but not with deoxynivalenol and 4-acetyl-NIV. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Fusarium culmorum is a major pathogen of grain crops. Infected plants accumulate deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), or nivalenol (NIV), which are mycotoxins of the trichothecene B group. These toxins are also produced by F. graminearum species complex. New trichothecenes structurally similar to trichothecenes B but lacking the carbonyl group on C-8, designated NX toxins, were recently discovered in atypical isolates of F. graminearum from North America. Only these isolates and a few strains of a yet to be characterized Fusarium species from South Africa are known to produce NX-2 and other NX toxins. Here, we report that among 20 F. culmorum strains isolated from maize, wheat, and oat in Europe and Asia over a period of 70 years, 18 strains produced NX-2 simultaneously with 3-ADON and DON or NIV. Rice cultures of strains producing 3-ADON accumulated NX-2 in amounts corresponding to 2–8% of 3-ADON (1.2–36 mg/kg). A strain producing NIV accumulated NX-2 and NIV at comparable amounts (13.6 and 10.3 mg/kg, respectively). In F. graminearum, producers of NX-2 possess a special variant of cytochrome P450 monooxygenase encoded by TRI1 that is unable to oxidize C-8. In F. culmorum, producers and nonproducers of NX-2 possess identical TRI1; the reason for the production of NX-2 is unknown. Our results indicate that the production of NX-2 simultaneously with trichothecenes B is a common feature of F. culmorum. [ABSTRACT FROM AUTHOR]

The production of mycotoxins is often interpreted as fungal response to cope with unfavorable growth conditions induced by toxic substances, environmental and biological factors. Soil covers influence soil environment, which consequently can change the abundance and composition of microbial communities. We investigated how plastic coverage (PC) influence soil fungi and mycotoxin occurrence (deoxynivalenol, nivalenol and zearalenone) compared to the traditional straw coverage (SC) in dependence of soil depth and time in a 3-year field experiment in strawberry cultivation. In total, 300 soil samples, resulting from two treatments, three soil layers, and ten sampling dates (n = 5), were analyzed for mycotoxins and ergosterol (proxy for soil fungal biomass) with liquid chromatography high resolution mass spectrometry and high-performance liquid chromatography with UV-detection, respectively. The modified microclimate under PC had no significant influence on fungal biomass, whereas SC promoted fungal biomass in the topsoil due to C-input. Mycotoxins were detected under both cover types in concentrations between 0.3 and 21.8 µg kg−1, mainly during strawberry establishment period and after fungicide application. Deoxynivalenol had the highest detection frequency with 26.3% (nivalenol: 8.3%, zearalenone: 8.7%). This study confirmed the in situ production of mycotoxins in soil, which seems mainly triggered by field treatment (fungicide application) and plant growth stage (establishment period) rather than on mulching type. Further investigations are necessary to better understand the influence of different agricultural practices and soil types on the production and fate of mycotoxins. [ABSTRACT FROM AUTHOR]

Aims: Cereals contaminated with type B trichothecene nivalenol (NIV) and its acetylated derivative 4‐acetyl‐nivalenol (4‐AcNIV) are a global mycotoxicological problem threatening the health of humans and livestock. Toxicological studies, quantitative determinations and screening for biodegrading micro‐organisms require massive amounts of pure toxins. However, the low yield from fungal cultures and high prices of NIV and 4‐AcNIV limit research progress in these areas. This work aimed to select Fusarium asiaticum mutant strains with enhanced production of NIV and 4‐AcNIV. Methods and Results: A total of 62 NIV‐producing F. asiaticum strains were isolated and compared regarding their ability to produce NIV. Strain RR108 had the highest yield of NIV among 62 field isolates surveyed and was then genetically modified for higher production. Targeted deletion of the FaFlbA gene, encoding a regulator of G protein signalling protein, resulted in a significant increase in NIV and 4‐AcNIV production in the FaFlbA deletion mutant ΔFaFlbA. The expression of three TRI genes involved in the trichothecene biosynthetic pathway was upregulated in ΔFaFlbA. ΔFaFlbA produced the highest amount of NIV and 4‐AcNIV when cultured in brown long‐grain rice for 21 days, and the yields were 2.07 and 2.84 g kg−1, respectively. The mutant showed reduced fitness, including reduced conidiation, loss of perithecial development and decreased virulence on wheat heads, which makes it biologically safe for large‐scale preparation and purification of NIV and 4‐AcNIV. Conclusions: The F. asiaticum mutant strain ΔFaFlbA presented improved production of NIV and 4‐AcNIV with reduced fitness and virulence in plants. Significance and Impact of the Study: Targeted deletion of the FaFlbA gene resulted in increased NIV and 4‐AcNIV production. Our results provide a practical approach using genetic modification for large‐scale mycotoxin production. [ABSTRACT FROM AUTHOR]

Fusarium cerealis is a causal agent of Fusarium Head Blight in wheat, and it produces both deoxynivalenol (DON) and nivalenol (NIV). Nevertheless, the effect of environmental factors on the growth and mycotoxin production of this species has not been studied so far. The objective of this study was to investigate the impact of environmental factors on the growth and mycotoxin production of F. cerealis strains. All strains were able to grow in a wide range of water activity (aW) and temperatures, but their mycotoxin production was influenced by strain and environmental factors. NIV was produced at high aW and temperatures, while optimal conditions for DON production were observed at low aW. Interestingly, some strains were able to simultaneously produce both toxins, which could pose a more significant risk for grain contamination.

Food security goes beyond food being available; the food needs to be free of contaminants. Trichothecenes mycotoxins, produced by Fusarium fungus, are. among the most frequently found contaminants of wheat. In this study, we evaluated the production of trichothecenes Deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-AcDON), 15-acetyldeoxynivalenol (15-AcDON), and nivalenol (NIV) by Fusarium meridionale, F. austroamericanum, and F. graminearum grown in wheat plants and rice medium. Fusarim meridionale was efficient only in the production of NIV (production range (pr) from 1340 to 2864 µg kg−1 in wheat plant), and F. austroamericanum in the production of 3-AcDON (pr from 50 to 192 µg kg−1 in wheat plant, and from 986 to 7045 µg kg−1 in rice medium) and DON (pr from 4076 to 13,701 µg kg−1 in wheat plant, and from 184 to 43,395 µg kg−1 in rice medium). Already, F. graminearum was efficient in the production of 3-AcDON only in rice medium (pr from 81 to 2342 µg kg−1), 15-AcDON in wheat plant (pr from 80 to 295 µg kg−1) and in rice medium (pr from 436 to 8597 µg kg−1), and DON also in wheat plant (pr from 7746 to 12,046 µg kg−1) and in rice medium (pr from 695 to 49,624 µg kg−1). The specificity of F. meridionale in the production of NIV but not the production of DON could generate a food security problem in regions where this species occurs and the amounts of NIV in grains and derivatives are not regulated in the food chain, as in Brazil. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is one of the most important diseases that occurs in cereal regions worldwide and causes serious economic damage. This disease can be caused by several Fusarium species with Fusarium graminearum sensu stricto being the most common pathogen isolated from several crops. The aim of this study was to report the occurrence of F. graminearum sensu stricto on rye grains collected from field samples in Argentina and to determine the potential ability to produce deoxynivalenol (DON), nivalenol (NIV) and zearalenone (ZEA). Based on morphological characteristics, the isolate was identified as F. graminearum sensu stricto. To confirm molecularly, portions of the RED and TRI genes were sequenced and showed 99% similarity with the F. graminearum sensu stricto sequences available in the NCBI database. The potential to produce DON, 15-acetyldeoxynivalenol (15-ADON) and ZEA was determined. Moreover, Koch´s postulates were carried out. To our knowledge, this is the first report of F. graminearum sensu stricto associated with rye kernels in Argentina.

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. [ABSTRACT FROM AUTHOR]

Background: Wheat is frequently contaminated by deoxynivalenol (DON) and nivalenol (NIV), which are type B trichothecenes produced by Fusarium fungi. Most problems related to these contaminants involve prolonged feed intake at low levels of contamination. This study investigated the occurrence of NIV and deoxynivalenol (DON) in wheat flour in flour factories in Khuzestan Providence, Iran. Methods: In total, 104 samples were collected in this study. An acetonitrile/water mixture (84:16, v/v) was used to extract the samples. The extracts were filtered and purified using a Whatman No. 4 paper and MycoSepTM 227 column. Then, they were evaporated to dryness at 40˚C under a nitrogen stream. After dissolving the dry residue in the mobile phase, containing a mixture of methanol, acetonitrile, and water (5:5:90, v/v/v), the contents of NIV and DON in the samples were measured in High-Performance Liquid Chromatography (HPLC) system with a column C18 (150 mm×4.6 mm ID, 5 µm) and a UV detector (220 nm). Results: The results showed that among 104 wheat flour samples, 28 (26.8%) and 54 (51.9%) samples were contaminated with NIV and DON, respectively. The mean and maximum concentrations were 118.75 and 2278 ng/g for NIV, and 593 and 67.88 ng/g for DON, respectively. Conclusion: Based on the findings, DON and NIV had significantly lower concentrations than the maximum tolerated level (1 µg/g), established by the Institute of Standards and Industrial Research of Iran. Therefore, there were no health risks for consumers at the studied contamination levels.

Surface-enhanced Raman spectroscopy (SERS) is a robust analytical tool applicable for the quick and accurate determination of mycotoxins. However, there hasn't been any attempt to use SERS for the quantitative detection of nivalenol (NIV) thus far. To improve the Raman signals of NIV, we fabricated a polydopamine-coated silver nanoflower (PDA-AgNFs) SERS substrate with strong "hot-spots". The PDA-AgNFs substrates showed superior SERS enhancement activities in the target analyte detection and quantification. It produced good substrate uniformity (relative standard deviation of SERS signals, RSD = 4.1% for substrate-to-substrate test, and 3.24% for spot-to-spot test), an enhancement factor of 2.87 × 106 towards rhodamine 6B (R 6 G), and detection sensitivity as low as 1 femtomolar (10−15 M) against R 6 G probe molecule. Moreover, the PDA-AgNFs SERS substrates were successfully used, for the first time, to detect NIV in corn, horse beans, and mushroom samples. The calibration curve showed a satisfactory linear fit based on the SERS intensities of different NIV concentrations. The detection limit (LOD) for the suggested approach was 0.22 nM (S/N = 3). Interestingly, the MTT assay experiment demonstrated that PDA-AgNFs had no toxicity against mammalian NIH-3T3 cells. The biocompatible PDA-AgNFs substrates with intense plasmonic effects and binding sites demonstrated impressive Raman enhancement, and could serve as an effective, label-free, and fast SERS-based analysis of NIV in real samples. [Display omitted] • Fabrication of PDA-inspired silver nano-flowers was successful. • The synthesized nano-flower particles were characterized extensively. • The synthesized PDA-AgNS exhibited excellent sensitivity, repeatability, signal reproducibility, and stability. • The proposed method was suitable for the detection of nivalenol mycotoxins in real samples. • PDA-AgNF nanosubstrate reduces cytotoxicity of the precursor species. [ABSTRACT FROM AUTHOR]

While mycotoxins are generally regarded as food contamination issues, there is growing interest in mycotoxins as environmental pollutants. The main sources of trichothecene and zearalenone mycotoxins in the environment are mainly attributed to Fusarium infested fields, where mycotoxins can wash off in infested plants or harvest residues. Subsequently, mycotoxins inevitably enter the soil. In this context, investigations into the effects, fate, and transport are still needed. However, there is a lack of analytical methods used to determine Fusarium toxins in soil matrices. We aimed to validate an analytical method capable of determining the toxins nivalenol (NIV), deoxynivalenol (DON), 15-acetyl-deoxynivalenol (15-AcDON), and zearalenone (ZEN), at environmentally relevant concentrations, in five contrasting agricultural soils. Soils were spiked at three levels (3, 9 and 15 ng g−1), extracted by solid-liquid extraction assisted with ultrasonication, using a generic solvent composition of acetonitrile:water 84:16 (v:v) and measured by LC–HRMS. Method validation was successful for NIV, DON, and 15-AcDON with mean recoveries > 93% and RSDr < 10%. ZEN failed the validation criteria. The validated method was applied to eight conventionally managed maize field soils during harvest season, to provide a first insight into DON, NIV, and 15-AcDON levels. Mycotoxins were present in two out of eight sampled maize fields. Soil mycotoxin concentrations ranged from 0.53 to 19.4 ng g−1 and 0.8 to 2.2 ng g−1 for DON and NIV, respectively. Additionally, we found indication that “hot-spot” concentrations were restricted to small scales (

The current study investigated the fungal diversity in freshly harvested oat samples from the two largest production regions in Brazil, Paraná (PR) and Rio Grande do Sul (RS), focusing primarily on the Fusarium genus and the presence of type B trichothecenes. The majority of the isolates belonged to the Fusarium sambucinum species complex, and were identified as F. graminearum sensu stricto (s.s.), F. meridionale, and F. poae. In the RS region, F. poae was the most frequent fungus, while F. graminearum s.s. was the most frequent in the PR region. The F. graminearum s.s. isolates were 15-ADON genotype, while F. meridionale and F. poae were NIV genotype. Mycotoxin analysis revealed that 92% and 100% of the samples from PR and RS were contaminated with type B trichothecenes, respectively. Oat grains from PR were predominantly contaminated with DON, whereas NIV was predominant in oats from RS. Twenty-four percent of the samples were contaminated with DON at levels higher than Brazilian regulations. Co-contamination of DON, its derivatives, and NIV was observed in 84% and 57.7% of the samples from PR and RS, respectively. The results provide new information on Fusarium contamination in Brazilian oats, highlighting the importance of further studies on mycotoxins.

Mycotoxins in small grains are a significant and long-standing problem. These contaminants may be produced by members of several fungal genera, including Alternaria, Aspergillus, Fusarium, Claviceps, and Penicillium. Interventions that limit contamination can be made both pre-harvest and post-harvest. Many problems and strategies to control them and the toxins they produce are similar regardless of the location at which they are employed, while others are more common in some areas than in others. Increased knowledge of host-plant resistance, better agronomic methods, improved fungicide management, and better storage strategies all have application on a global basis. We summarize the major pre- and post-harvest control strategies currently in use. In the area of pre-harvest, these include resistant host lines, fungicides and their application guided by epidemiological models, and multiple cultural practices. In the area of post-harvest, drying, storage, cleaning and sorting, and some end-product processes were the most important at the global level. We also employed the Nominal Group discussion technique to identify and prioritize potential steps forward and to reduce problems associated with human and animal consumption of these grains. Identifying existing and potentially novel mechanisms to effectively manage mycotoxin problems in these grains is essential to ensure the safety of humans and domesticated animals that consume these grains.

Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe is a major disease of wheat (Triticum aestivum L.). FHB preferentially infects immature spikes and mycotoxins accumulate in developing grains, reducing yield and nutritional quality. The mycotoxins are type B trichothecene group of compounds including deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), and nivalenol (NIV) that also act as virulence factors during FHB infection and disease progression. An enzyme UDP-glucosyl transferase (EC 2.4.1.x) glycosylates DON to deoxynivalenol-3-glucoside (D3G), thus rendering it ineffective as a virulence factor. The present study analysed the association of DON, 3A-DON, and D3G with FHB severity using in vitro spike culture for FHB screening. The mycotoxins in FHB-resistant and -susceptible spikes were extracted using a single step extraction method, and their concentration was determined using an LC-MS/MS method that differentiated all the five mycotoxins. Pairwise comparisons of FHB-resistant and -susceptible spike culture derived variants (SCDV) using Tukey's method showed significant (P ≤ 0.001) variation for disease severity and accumulation of DON, 3-ADON, and D3G at seven and nine days after fungal inoculation. FHB severity showed a significant positive correlation to the accumulation of DON, 3-ADON, and D3G, but an inverse correlation to the ratio between D3G and DON. [ABSTRACT FROM AUTHOR]

There is evidence that microalgae phenolic compounds can inhibit the growth of toxigenic fungi. This study aimed to evaluate the ability of microalgae phenolic extracts to inhibit trichothecene production by Fusarium genus and thereby identify parameters that can promote a new technology to avoid contamination of crops by mycotoxins. The microalgae phenolic acids (Spirulina sp. and Nannochloropsis sp.) were extracted with methanol, clarified and resuspended in water. The in vitro experiment involved adding the phenolic extract from each microalga (40 μg/mL) to Petri dishes containing culture medium and previously sterilized wheat grains, with subsequent inoculation of an isolate belonging to the F. graminearum species complex. The control was cultured with sterile water. Treatment with the fungicide tebuconazole (0.6 mg/mL) was also performed. Petri dishes were incubated at 25 °C, with a light/dark photoperiod of 12–12 h. After 168 h, the samples were extracted by the adapted QuEChERS method; the trichothecenes (nivalenol, deoxynivalenol and acetylates) were identified and quantified by high-performance liquid chromatography. When the phenolic extracts from microalgae were applied, the characteristic peak of nivalenol was not detected, suggesting total inhibition, whereas, the nivalenol content increased (15%) in the presence of tebuconazole. Both microalgae phenolic extracts also had a promising effect on the inhibition of deoxynivalenol, with no detection (Nannochloropsis sp. extract) and 62% reduction (Spirulina sp. extract). The application of the fungicide tebuconazole increased the deoxynivalenol concentration. Both microalgae phenolic extracts and tebuconazole decreased the detection of acetylates. Thus, phenolic extracts from microalgae were more efficient than tebuconazole as antifungal and antimycotoxigenic agents in cultures in vitro. Unlabelled Image • Microalgae phenolic extracts showed antimycotoxigenic effect in cultures in vitro. • Microalgae phenolic extracts act mainly against nivalenol production. • Nannochloropsis sp. phenolic extract inhibited deoxynivalenol production completely. • Spirulina sp. phenolic extract inhibited 62% of deoxynivalenol production. • Fungicide tebuconazole resulted in an increase in deoxynivalenol concentration. [ABSTRACT FROM AUTHOR]

Lymphocytes are involved in the adaptive immune response and are highly sensitive to type B trichothecenes. In grains and their products, deoxynivalenol (DON) is the most widely distributed trichothecene. It usually co-occurs with other type B members, such as nivalenol (NIV) and fusarenon-X (FX), because they are all produced by the same Fusarium fungi. However, the combined effects of mycotoxins are complex and cannot be predicted based on individual toxicity. Thus, the adverse effects of combined toxins are of increasing concern. The aim of this study was to compare the toxicity to lymphoid tissues of mice of DON alone or mixed with NIV or FX. Forty, 3-week-old male ICR mice were given a single oral administration of a vehicle control, one toxin, binary, or ternary mixtures and then sacrificed at 12 h after exposure. Mice treated with FX alone showed marked nuclear condensation and fragmentation of lymphocytes in the cortical thymus and germinal center of Peyer's patches and spleen. Similarly, these animals clearly displayed TUNEL- and Caspase-3-positive cells in the regions. In contrast, minimal changes were noticed in the lymphoid tissues of mice receiving combined toxins when compared to this toxin alone. In addition, oral exposure to FX alone significantly up-regulated the relative expression of Bax , Caspase-3 , Caspase-9 , and Trp53. These data increase our understanding of the toxic actions of DON, NIV, and FX alone or in combination to lymphocytes and can be used to assess the possible risk associated with their co-occurrences in foodstuffs to human and animal health. • FX alone showed marked apoptotic cell death in the lymphoid tissues of mice after oral administration. • Mycotoxin mixtures are less toxicity to lymphocytes apoptosis than that of individual exposure. • In natural co-occurrence, the combined mycotoxins might be less impact on lymphoid mortality. [ABSTRACT FROM AUTHOR]

A simple and reliable method for the simultaneous determination of major type B trichothecene mycotoxins, deoxynivalenol (DON) and nivalenol (NIV), along with their 3-β-d-glucosides (DON-3-glucoside (DON3G) and NIV-3-glucoside (NIV3G)) in baby formula and Korean rice wine was validated in the present study. The method was based on immunoaffinity cleanup followed by analysis using an HPLC-UV technique. The method was validated in-house for two matrices as follows: linearity (R2 > 0.99) was established in the range of 20–1000 μg kg–1; accuracy (expressed as recovery) ranged from 78.7 to 106.5% for all the analytes; good intermediate precision (relative standard deviation < 12%), and adequate detection and quantitation limits (< 4.4 and < 13.3 μg kg–1, respectively) were achieved. Furthermore, the estimated measurement expanded uncertainty was determined to be 4–24%. The validated method was successfully applied to the analysis of 31 baby formulas and Korean rice wines marketed in Korea. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Characterization of 7 novel nivalenol (NIV)- and NIV-3-glucoside (NIV3 G) metabolites in rats. • Development of LC–MS/MS based methods for analysis of NIV(3 G) metabolites in rat excrements. • Similar metabolization of NIV and deoxynivalenol in rats, but with different metabolite patterns. • NIV3 G is largely hydrolyzed in the GI tract of rats, but also extensively further metabolized. • The systemic exposure to NIV is roughly 30 times lower after NIV3 G consumption than after NIV dosage. Abstract Plant-derived mycotoxin conjugates like deoxynivalenol-3-glucoside can be partly hydrolyzed to their aglycones in vivo , albeit to different extent depending on the mycotoxin conjugate and on the animal species. The aim of this work was to investigate the metabolization of the trichothecene mycotoxin nivalenol (NIV) and the fate of its modified form NIV-3-glucoside (NIV3G) in rats. To that end, 350 μg/kg body weight of NIV and the equimolar dose of NIV3G were administered to six rats by gavage in a 5 × 6 design and excreta were collected for 2 days after each treatment. For further analysis of NIV and NIV3G metabolites in rat urine and feces, seven novel NIV- and NIV3G metabolites including NIV sulfonates (NIVS) 1, 2 and 3, deepoxy-NIV (DNIV), DNIV sulfonate 2, NIV3G sulfonate (NIV3GS) 2 and NIV-3-glucuronide were produced, isolated and characterized. Subsequently, LC–MS/MS based methods for determination of NIV, NIV3G and their metabolites in excreta samples were developed, validated and applied. The biological recoveries of administered toxins in the form of their fecal and urinary metabolites were 57 ± 21% for NIV and 94 ± 36% for NIV3G. The majority of NIV and NIV3G metabolites was excreted into feces, with DNIV and NIVS 2 as major NIV metabolites and NIV3GS 2 and DNIV as major metabolites of NIV3G. Only 1.5% of the administered NIV3G was recovered in urine, with NIV3G itself as major urinary metabolite. The biological recovery of free NIV in urine was approximately 30 times lower after treatment with NIV3G than after administration of NIV, indicating that exposure of rats to NIV3G results in lower toxicity than exposure to NIV. [ABSTRACT FROM AUTHOR]

Crown and root rot of wheat, caused by Fusarium spp., limit crop yields worldwide, from rotting of seeds, seedlings, crowns, roots and basal plant stems. Virulence factors and virulence and aggressiveness of Fusarium spp. were investigated for isolates from Iran, obtained from wheat plants with crown and root rot symptoms. Forty isolates of Fusarium were used in this research. Among the isolates, nivalenol (NIV) was detected as the dominant trichothecene chemotype produced. Production of trichothecenes and zearalenone (ZEA) in autoclaved rice cultures of Fusarium isolates was analyzed using high performance liquid chromatography. The levels of NIV ranged from 258 to 1246 µg kg-1, of deoxynivalenol (DON) from 45 to 1411 µg kg-1, and of ZEA from 53 to 3220 µg kg-1. All Fusarium isolates produced cellulase and pectinase enzymes. Positive correlation was observed between activity of cell wall degrading enzymes (CWDEs) produced by the isolates and their pathogenicity on wheat leaf segments. Virulence of trichothecene-producing isolates was greater than that of nontrichothecene-producing isolates. Considerable association was detected between the capability of Fusarium spp. isolates to produce virulence factors (such as mycotoxins and CWDEs) and their pathogenicity on wheat. [ABSTRACT FROM AUTHOR]

Highlights • The effect of six cropping factors on Fusarium mycotoxins in wheat was investigated. • We observed high DON and ZEA contents after previous crop maize and reduced tillage. • High NIV contents were associated with samples from ploughed fields. • Soya bean as a previous crop might contribute to reduce the risk of DON and NIV. • In Switzerland, NIV is most likely produced by four different Fusarium species. • We suggest that F. poae has a different ecological niche than that of F. graminearum. Abstract Over an eight-year period, 686 winter wheat grain samples and information on their cropping history were obtained from Swiss growers. To estimate the risk of Fusarium head blight (FHB), grains were examined for Fusarium species incidence, mycotoxin content as well as the abundance of F. graminearum (FG) and F. poae (FP) DNA and three chemotypes, 15-acetyl-deoxynivalenol (15ADON), 3-acetyl-deoxynivalenol (3ADON) and nivalenol (NIV). Of all Fusarium species, FG and FP were predominant, and the average abundance of the FG DNA was three times higher compared with that of FP. The average detection of the 15ADON chemotype was twice as high as those of 3ADON and NIV, respectively. Deoxynivalenol (DON), zearalenone (ZEA) and nivalenol (NIV) were the most frequently detected toxins. For DON, 11% and for ZEA, 7% of all samples exceeded the European maximum limits for unprocessed cereals intended for human consumption. Furthermore, NIV was most likely produced by four different Fusarium species. A multiple correspondence analysis revealed that high levels of FG and DON were mainly observed in grain samples from fields with the previous crop maize, reduced tillage, cultivars with poor FHB resistance and strobilurin-based fungicides. Other previous crops and/or ploughing decreased the DON content by 78 to 95%. ZEA showed a similar pattern. In contrast, high levels of FP and NIV were associated with samples from ploughed fields and the previous crop canola. These findings and the negative correlations between FP DNA and FG incidence, ZEA and DON suggest a different ecological niche for FP or diverging requirements for growth and infection. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is one of the most important diseases that occurs in cereal regions worldwide and causes serious economic damage. This disease can be caused by several Fusarium species with Fusarium graminearum sensu stricto being the most common pathogen isolated from several crops. The aim of this study was to report the occurrence of F. graminearum sensu stricto on rye grains collected from field samples in Argentina and to determine the potential ability to produce deoxynivalenol (DON), nivalenol (NIV) and zearalenone (ZEA). Based on morphological characteristics, the isolate was identified as F. graminearum sensu stricto. To confirm molecularly, portions of the RED and TRI genes were sequenced and showed 99% similarity with the F. graminearum sensu stricto sequences available in the NCBI database. The potential to produce DON, 15-acetyldeoxynivalenol (15-ADON) and ZEA was determined. Moreover, Koch´s postulates were carried out. To our knowledge, this is the first report of F. graminearum sensu stricto associated with rye kernels in Argentina. [ABSTRACT FROM AUTHOR]

Abstract Food and feed commodities are often contaminated by more than one mycotoxin. Among the several combinations that frequently occur, fusariotoxins are often mentioned. The multi-mycotoxins contamination is a serious threat for health. In the present study we investigated the toxic interactions between deoxynivalenol (DON), nivalenol (NIV), and fusarenon-X (FX) in Jurkat T cells by using the MTT assay. The tested mycotoxins alone or in combination had a dose dependent effect on proliferating lymphocytes. According to IC 50 , it could be classified in decreasing order of toxicity: FX > NIV > DON > DON + FX > NIV + FX > DON + NIV > DON + NIV + FX. The type of mycotoxin interactions was assessed by calculating the combination index (CI) and the dose reduction index (DRI). Our data indicate that an antagonistic effect was strongly observed in binary combination between DON and NIV at higher concentrations and ternary mixtures. Meanwhile, the DON and FX mixtures generated moderate antagonism, while NIV and FX provoked different interactions. The effects of tested mycotoxins on apoptosis were also determined using a FACScan flow cytometer. At IC 75 , the percentages of apoptotic cells in all treatment groups were significantly different when compared to control group but no significant differences among treatment groups was observed. Taken together, our data suggest that immunotoxicity among multi-mycotoxins contamination cannot be predicted based on individual effects but depends on the mixtures, ratio and/or concentrations in the product, as well as type of target cells. Highlights • The natural co-occurrence of mycotoxins in cereal grains and animal feeds are frequently noted around the world. • DON, NIV, and FX alone or in combination induce cytotoxicity and apoptosis on Jurkat human T cells. • The toxic interaction depends on the mixed of mycotoxin, their ratio and concentrations, as well as type of target cells. [ABSTRACT FROM AUTHOR]

A 2-year field experiment was conducted to determine the effects of Fusarium sporotrichioides, F. langsethiae, or F. poae on durum wheat plants artificially inoculated at different growth stages. The percentage of symptomatic kernels was similar among the three species, but incidence of infected kernels was lower for F. langsethiae. Kernel colonization was higher when plants were inoculated before and during anthesis for F. sporotrichioides and F. poae, but unaffected by timing of inoculation for F. langsethiae. Production of T-2/HT-2 toxins was higher for F. sporotrichioides than for F. langsethiae. Significant accumulations of nivalenol were detected for F. poae. Across all three species, there was a weak correlation (r = 0.16; P = 0.031) between the incidences of symptomatic and infected kernels, but a stronger correlation (r = 0.53; P < 0.001) between infection incidence and the quantity of fungal DNA (species-specific) in kernels. Mycotoxin content was correlated (r > 0.58; P < 0.007) with infection incidence or fungal DNA in kernels, but only for F. sporotrichioides and F. poae. [ABSTRACT FROM AUTHOR]

Fusarium graminearum, the causal agent of Fusarium head blight (FHB), produces trichothecenes including deoxynivalenol (DON), nivalenol (NIV), and 3,7,15-trihydroxy-12,13-epoxytrichothec-9-ene (NX-3). These toxins contaminate grains and cause profound health problems in humans and animals. To explore exploiting a fungal self-protection mechanism in plants, we examined the ability of F. graminearum trichothecene 3-O-acetyltransferase (FgTri101) to detoxify several key trichothecenes produced by F. graminearum: DON, 15-ADON, NX-3, and NIV. FgTri101 was cloned from F. graminearum and expressed in Arabidopsis plants. We compared the phytotoxic effects of purified DON, NIV, and NX-3 on the root growth of transgenic Arabidopsis expressing FgTri101. Compared to wild type and GUS controls, FgTri101 transgenic Arabidopsis plants displayed significantly longer root length on media containing DON and NX-3. Furthermore, we confirmed that the FgTri101 transgenic plants acetylated DON to 3-ADON, 15-ADON to 3,15-diADON, and NX-3 to NX-2, but did not acetylate NIV. Approximately 90% of the converted toxins were excreted into the media. Our study indicates that transgenic Arabidopsis expressing FgTri101 can provide plant protection by detoxifying trichothecenes and excreting the acetylated toxins out of plant cells. Characterization of plant transporters involved in trichothecene efflux will provide novel targets to reduce FHB and mycotoxin contamination in economically important plant crops.

Fusarium graminearum and Fusarium culmorum are among the major causal agents of Fusarium head blight, which reduces both crop yield and grain quality in wheat worldwide. The present study was conducted with 57 isolates collected from 23 different locations across four provinces in the 2011/2012 growing season. Out of the 57 Fusarium isolates, 32 isolates were identified as F. graminearum and 25 isolates were identified as F. culmorum. Both pathogens are of particular importance, since they produce several mycotoxins. Among these, deoxynivalenol (DON) and nivalenol (NIV) are well known for their toxicity towards human and animal health. Genetic chemotyping of F. graminearum and F. culmorum species indicated that both DON and NIV chemotypes were present in the surveyed area. Of the 32 F. graminearum isolates, the primer sets Tri13DON and Tri13NIV identified 87.5% as DON chemotypes and 12.5% as NIV chemotypes. Similarly, the 25 F. culmorum isolates displayed 88% DON and 12% NIV chemotypes. In addition, DON acetylated derivatives, 3-acetyldeoxynivalenol (3-AcDON) and 15-AcDON, were identified by polymerase chain reaction based methods. It was determined that 15-AcDON sub-chemotype was dominant in F. graminearum populations, whereas 3-AcDON was dominant in F. culmorum populations. This is the first report demonstrating the presence of F. graminearum and F. culmorum isolates and the distribution of 3-AcDON and 15-AcDON chemotypes in both Fusarium species in wheat fields of eastern Mediterranean region of Turkey.

The transformation of deoxynivalenol (DON), nivalenol (NIV), and their glucosides (DON3G and NIV3G) during the malting of grains of two wheat varieties was studied. The concentration of DON3G and NIV3G started to increase significantly before the concentration of DON and NIV increased. This may reflect the transformation of the parent mycotoxin forms into their glucosides due to xenobiotic detoxification reactions. After a sharp rise during the last 2 days of the process (day 6 and 7), the DON concentration reached 3010 ± 338 µg/kg in the Legenda wheat-based malt and 4678 ± 963 µg/kg in the Pokusa wheat-based malt. The NIV concentration, at 691 ± 65 µg/kg, remained the same as that in the dry grain. The concentration of DON3G in the Legenda and Pokusa wheat-based malt was five and three times higher, respectively, than that in the steeped grain. The concentration of NIV3G in the Legenda wheat-based malt was more than twice as high as that in the steeped grain. The sharp increase in the concentration of DON at the end of the malting process reflected the high pathogen activity. We set aside some samples to study a batch that was left undisturbed without turning and aeration, for the entire period of malting. The concentration of DON in the malt produced from the latter batch was 135% and 337% higher, for Legenda and Pokusa, respectively, than that in the malt produced from the batch that was turned and aerated. The NIV concentration was 22% higher in the latter batch.

Fusarium head blight (FHB) can cause contamination of cereal grain with mycotoxins. Triticale is also infected with FHB; however, it is more resistant than wheat to head infection. The aim of this study was to identify triticale lines that combine low head infection with low toxin contamination. Resistance to FHB of 15 winter triticale and three winter wheat lines was evaluated over a three-year experiment established in two locations. At the anthesis stage, heads were inoculated with Fusarium culmorum isolates. The FHB index was scored and the percentage of Fusarium-damaged kernels (FDKs) assessed. The grain was analysed for type B trichothecenes (deoxynivalenol and derivatives, nivalenol) and zearalenone content. The average FHB index was 10.7%. The proportion of FDK was 18.1% (weight) and 21.6% (number). An average content of deoxynivalenol amounted to 7.258 mg/kg and nivalenol to 5.267 mg/kg. In total, it was 12.788 mg/kg of type B trichothecenes. The zearalenone content in the grain was 0.805 mg/kg. Relationships between FHB index, FDK, and mycotoxin contents were statistically significant for triticale lines; however, they were stronger for FDK versus mycotoxins. Triticale lines combing all types of FHB resistance were found, however the most resistant ones were less resistant that wheat lines with the Fhb1 gene.

Trichothecenes are the most common mycotoxins contaminating small grain cereals worldwide. The C12,13 epoxide group in the trichothecenes was identified as a toxic group posing harm to humans, farm animals, and plants. Aerobic biological de-epoxidation is considered the ideal method of controlling these types of mycotoxins. In this study, we isolated a novel trichothecene mycotoxin-de-epoxidating bacterium, Desulfitobacterium sp. PGC-3-9, from a consortium obtained from the soil of a wheat field known for the occurrence of frequent Fusarium head blight epidemics under aerobic conditions. Along with MMYPF media, a combination of two antibiotics (sulfadiazine and trimethoprim) substantially increased the relative abundance of Desulfitobacterium species from 1.55% (aerobic) to 29.11% (aerobic) and 28.63% (anaerobic). A single colony purified strain, PGC-3-9, was isolated and a 16S rRNA sequencing analysis determined that it was Desulfitobacterium. The PGC-3-9 strain completely de-epoxidated HT-2, deoxynivalenol (DON), nivalenol and 15-acetyl deoxynivalenol, and efficiently eliminated DON in wheat grains under aerobic and anaerobic conditions. The strain PGC-3-9 exhibited high DON de-epoxidation activity at a wide range of pH (6–10) and temperature (15–50 °C) values under both conditions. This strain may be used for the development of detoxification agents in the agriculture and feed industries and the isolation of de-epoxidation enzymes.

Biotic stress, which includes infection by pathogenic fungi, causes losses of wheat yield in terms of quantity and quality. Ear Fusarium is caused by strains of F. graminearum and F. culmorum, which can produce mycotoxins—deoxynivalenol (DON) and nivalenol (NIV). One of the wheat’s defense mechanisms against stressors is the activation of biosynthesis pathways of antioxidant compounds, including ferulic acid. The aim of the study was to conduct pilot studies on the basis of which neural models were created that would examine the impact of the variety and weather conditions on the concentration of ferulic acid, and link its content with the concentration of deoxynivalenol and nivalenol. The plant material was 23 winter wheat genotypes with different Fusarium resistance. The field experiment was conducted in 2011–2013 in Poland in three experimental combinations, namely: with full chemical protection; without chemical protection, but infested with natural disease (control); and in the absence of fungicidal protection, with artificial inoculation by genus Fusarium fungi. As a result of the pilot studies, three neural models—FERUANN analytical models (ferulic acid content), DONANN (deoxynivalenol content) and NIVANN (nivalenol content)—were produced. Each model was based on 14 independent features, 12 of which were in the form of quantitative data, and the other two were presented as qualitative data. The structure of the created models was based on an artificial neural network (ANN) of the multilayer perceptron (MLP) with two hidden layers. The sensitivity analysis of the neural network showed the two most important features determining the concentration of ferulic acid, deoxynivalenol, and nivalenol in winter wheat seeds. These are the experiment variant (VAR) and winter wheat variety (VOW).

The mycotoxins deoxynivalenol (DON) and nivalenol (NIV), worldwide cereal contaminants, raise concerns for animal and human gut health, following contaminated food or feed ingestion. The impact of DON and NIV on intestinal mucosa was investigated after acute exposure, in vitro and in vivo. The histological changes induced by DON and NIV were analyzed after four-hour exposure on pig jejunum explants and loops, two alternative models. On explants, dose-dependent increases in the histological changes were induced by DON and NIV, with a two-fold increase in lesion severity at 10 µM NIV. On loops, NIV had a greater impact on the mucosa than DON. The overall proliferative cells showed 30% and 13% decrease after NIV and DON exposure, respectively, and NIV increased the proliferative index of crypt enterocytes. NIV also increased apoptosis at the top of villi and reduced by almost half the proliferative/apoptotic cell ratio. Lamina propria cells (mainly immune cells) were more sensitive than enterocytes (epithelial cells) to apoptosis induced by NIV. Our results demonstrate a greater impact of NIV than DON on the intestinal mucosa, both in vitro and in vivo, and highlight the need of a specific hazard characterization for NIV risk assessment.

Fusarium poae is one of the Fusarium species commonly detected in wheat kernels affected by Fusarium Head Blight. Fusarium poae produces a wide range of mycotoxins including nivalenol (NIV). The effect of temperature on colony growth and NIV production was investigated in vitro at 5–40 °C with 5 °C intervals. When the data were fit to a Beta equation (R 2  ≥ 0.97), the optimal temperature was estimated to be 24.7 °C for colony growth and 27.5 °C for NIV production. The effects of temperature on infection incidence, fungal biomass, and NIV contamination were investigated by inoculating potted durum wheat plants at full anthesis; inoculated heads were kept at 10–40 °C with 5 °C intervals for 3 days and then at ambient temperature until ripening. Temperature significantly affected the incidence of floret infection and fungal biomass (as indicated by DNA amount) in the affected heads but did not affect NIV content in the head tissue. Inoculation of potted plants with F. poae did not reduce yield. [ABSTRACT FROM AUTHOR]

Abstract Fusarium meridionale has been frequently isolated from soybean in Argentina and showed similar pathogenicity as F. graminearum sensu stricto. However, no data on their growth and mycotoxin production under different environmental conditions are yet available. The aims of this study were: to determine the effect of temperature, water activity (a W) and strain on growth of F. meridionale and to evaluate deoxynivalenol (DON) and nivalenol (NIV) production in a soybean based medium. The results showed that optimal conditions for F. meridionale growth were at 25 °C and 0.98–0.99 a W. Deoxynivalenol production was favored at 25 °C and 0.96 a W while NIV production was strain-dependent, being 30 °C and 0.98 a W optimal conditions for F. meridionale B2300 strain and 20 °C and 0.98 a W for F. meridionale F5043 and F. meridionale 5048 strains. These conditions are similar to those observed at pre-harvest stage in soybean crop, thus control strategies need to be considered to reduce the risk of the occurrence of DON and NIV in harvested grains. Highlights • Optimal conditions for Fusarium meridionale growth were at 25°C and 0.98-0.99 a W. • Deoxynivalenol production was favored at 25°C and 0.96 a W. • NIV production was strain-dependent. • Fusarium meridionale was able to growth and to produce mycotoxins under the conditions observed at R6 stage in soybean [ABSTRACT FROM AUTHOR]

In this study, 100 samples of beer available on the Polish market have been HPLC-analysed for the occurrence of mycotoxins: nivalenol, deoxynivalenol and deoxynivalenol-3-glucoside. Fractions of positive beer samples were 56, 83 and 67% for nivalenol, deoxnivalenol and deoxynivalenol-3-glucoside, respectively. Mean concentrations of the analytes found in the beer samples were (all data in μg/L): 2.4 ± 1.9 (range 0.5–7.6), 9.0 ± 12.7 (range 1.0–73.6), 9.2 ± 7.5 (range 2.0–35.8) for nivalenol, deoxynivalenol and deoxynivalenol-3-glucoside, respectively. Higher concentrations of deoxynivalenol-3-glucoside than deoxynivalenol found in many beer samples reflect the activity of glucosyltransferase enzymes during the grain malting process when they assist secondary biosynthesis of deoxynivalenol-3-glucoside. From the toxicological point of view, the above mycotoxin levels found in beer may be regarded as safely low. The vast majority of the samples contained deoxynivalenol. The deoxynivalenol-3-glucoside co-occurring with deoxynivalenol from the point of view of food safety can increase the toxicological hazard. Mycotoxins in beer available on the Polish market have not been earlier reported at all. [ABSTRACT FROM AUTHOR]

Abstract The main aim of this research was to evaluate the toxicokinetic characteristics of fusarenon-X (FX) and its metabolite, nivalenol (NIV), in goats. The amounts of FX and NIV in post-mitochondrial (S-9), microsomal and cytosolic fractions of diverse tissues of the goat were also investigated. FX was intravenously (iv) or orally (po) administered to goats at dosages of 0.25 and 1 mg/kg bw, respectively. The concentrations of FX and NIV in plasma, feces and urine were quantified by liquid chromatography tandem-mass spectrometry (LC-ESI-MS/MS). The concentrations of FX in plasma were quantified up to 8 h with both routes of administration. A large amount of NIV (metabolite) was quantifiable in plasma, urine and feces after both administrations. The C max value of FX was 413.39 ± 206.84 ng/ml after po administration. The elimination half-life values were 1.64 ± 0.32 h and 4.69 ± 1.25 h after iv and po administration, respectively. In vitro experiments showed that the conversion FX-to-NIV mainly occurs in the liver microsomal fraction. This is the first study that evaluates the fate and metabolism of FX in ruminant species. Highlights • This is the first study that evaluates the fate and metabolism of FX in ruminant species. • FX is absorbed from the gastrointestinal tract with a relatively low bioavailability in goats. • The liver is the organ responsible for the FX-to-NIV biotransformation in goats. • FX is excreted mainly as NIV in the feces of goats after p.o. administration of FX. [ABSTRACT FROM AUTHOR]