Emerging Fusarium and Alternaria Mycotoxins: Occurrence, Toxicity and Toxicokinetics

The flavonoid chrysin protects against zearalenone induced reproductive toxicity in male mice

The mycotoxin zearalenone (ZEA) has strong estrogenic effects and elicits reproductive toxicity. Chrysin is a natural flavonoid found in many plant and has a broad range of pharmacological activities, including anticancer, antioxidant and anti-inflammatory. The present study aimed to investigate the potential protective effects of chrysin against ZEA toxicity. Mice received chrysin (5 or 20 mg/kg; i.g.) for ten days, and then received a single injection of ZEA (40 mg/kg). Two days thereafter, blood and testes were collected. ZEA decreased number and motility of sperm, plasma testosterone levels, enzymatic (glutathione peroxidase, glutathione reductase, glutathione-S-transferase) and non-enzimatic defenses (reduced glutathione). Moreover, ZEA increased 4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine levels, myeloperoxidase activity and levels of proinflammatory cytokines (interleukins-1β and 6, tumor necrosis factor alpha). ZEA also decreased levels of anti-inflammatory cytokine interleukin-10 and increased activity of caspases 3 and 9. Chrysin treatment increased the number and motility of sperm, testosterone levels, restored antioxidant defenses and reduced the inflammation and apoptosis process. In summary, chrysin attenuated the toxic effects caused by ZEA in blood and testes of mice, suggesting a potential preventive treatment against the deleterious effects of ZEA.

Red- and Blue-Light Sensing in the Plant Pathogen Alternaria alternata Depends on Phytochrome and the White-Collar Protein LreA

Light controls many processes in filamentous fungi. The study of light regulation in a number of model organisms revealed an unexpected complexity. Although the molecular components for light sensing appear to be widely conserved in fungal genomes, the regulatory circuits and the sensitivity of certain species toward specific wavelengths seem different. In N. crassa, most light responses are triggered by blue light, whereas in A. nidulans, red light plays a dominant role. In Alternaria alternata, both blue and red light appear to be important. In A. alternata, photoreceptors control morphogenetic pathways, the homeostasis of reactive oxygen species, and the production of secondary metabolites. On the other hand, high-osmolarity sensing required FphA and LreA, indicating a sophisticated cross talk between light and stress signaling.

The filamentous fungus Alternaria alternata is a common postharvest contaminant of food and feed, and some strains are plant pathogens. Many processes in A. alternata are triggered by light. Interestingly, blue light inhibits sporulation, and red light reverses the effect, suggesting interactions between light-sensing systems. The genome encodes a phytochrome (FphA), a white collar 1 (WC-1) orthologue (LreA), an opsin (NopA), and a cryptochrome (CryA) as putative photoreceptors. Here, we investigated the role of FphA and LreA and the interplay with the high-osmolarity glycerol (HOG) mitogen-activated protein (MAP) kinase pathway. We created loss-of function mutations for fphA, lreA, and hogA using CRISPR-Cas9 technology. Sporulation was reduced in all three mutant strains already in the dark, suggesting functions of the photoreceptors FphA and LreA independent of light perception. Germination of conidia was delayed in red, blue, green, and far-red light. We found that light induction of ccgA (clock-controlled gene in Neurospora crassa and light-induced gene in Aspergillus nidulans) and the catalase gene catA depended on FphA, LreA, and HogA. Light induction of ferA (a putative ferrochelatase gene) and bliC (bli-3, light regulated, unknown function) required LreA and HogA but not FphA. Blue- and green-light stimulation of alternariol formation depended on LreA. A lack of FphA or LreA led to enhanced resistance toward oxidative stress due to the upregulation of catalases and superoxide dismutases. Light activation of FphA resulted in increased phosphorylation and nuclear accumulation of HogA. Our results show that germination, sporulation, and secondary metabolism are light regulated in A. alternata with distinct and overlapping roles of blue- and red-light photosensors.

Multi LC-MS/MS and LC-HRMS Methods for Determination of 24 Mycotoxins including Major Phase I and II Biomarker Metabolites in Biological Matrices from Pigs and Broiler Chickens

A reliable and practical multi-method was developed for the quantification of mycotoxins in plasma, urine, and feces of pigs, and plasma and excreta of broiler chickens using liquid chromatography–tandem mass spectrometry. The targeted mycotoxins belong to the regulated groups, i.e., aflatoxins, ochratoxin A and Fusarium mycotoxins, and to two groups of emerging mycotoxins, i.e., Alternaria mycotoxins and enniatins. In addition, the developed method was transferred to a LC-high resolution mass spectrometry instrument to qualitatively determine phase I and II metabolites, for which analytical standards are not always commercially available. Sample preparation of plasma was simple and generic and was accomplished by precipitation of proteins alone (pig) or in combination with removal of phospholipids (chicken). A more intensive sample clean-up of the other matrices was needed and consisted of a pH-dependent liquid–liquid extraction (LLE) using ethyl acetate (pig urine), methanol/ethyl acetate/formic acid (75/24/1, v/v/v) (pig feces) or acetonitrile (chicken excreta). For the extraction of pig feces, additionally a combination of LLE using acetone and filtration of the supernatant on a HybridSPE-phospholipid cartridge was applied. The LC-MS/MS method was in-house validated according to guidelines defined by the European and international community. Finally, the multi-methods were successfully applied in a specific toxicokinetic study and a screening study to monitor the exposure of individual animals.

Development of Sensitive and Reliable UPLC-MS/MS Methods for Food Analysis of Emerging Mycotoxins in China Total Diet Study

With the climatic changes that have taken place during the last decade, the spectrum of fungal pathogens as well as mycotoxins has considerably changed. As a result, some emerging mycotoxins have been shown to occur frequently in agricultural products. In this study, a sensitive and reliable method for the determination of 10 emerging mycotoxins (beauvericin, enniatin A, enniatin A1, enniatin B, enniatin B1, alternariol, alternariol monomethyl ether, altenuene, tentoxin, and tenuazonic acid) in 12 different food matrices (cereals, legumes, potatoes, meats, eggs, aquatic foods, dairy products, vegetables, fruits, sugars, beverages, and alcohol beverages) was developed and validated. After a simple extraction, a one-step sample clean-up by a HLB solid phase extraction (SPE) column was sufficient for all 12 food matrices prior to analysis with ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). Isotope internal standards 13C-TeA, TEN-d₃, and 13C-AFB2 were used for accurate quantification. Validation in terms of linearity, selectivity, sensitivity, accuracy, and precision (intra and inter-day variability) were evaluated for the 10 mycotoxins in all selected matrices. The sensitivity varied from 0.0004 to 0.3 ng mL-1 (limits of detection) and from 0.002 to 0.9 ng mL-1 (limits of quantitation). The recoveries of 10 mycotoxins in fortified samples were from 60.6% to 164% including very low spiking levels in all 12 food matrices, with relative standard deviations (RSDs) less than 12%. The proposed methodology was applied to the analysis of 60 samples collected from five provinces within the 6th China Total Diet Study with the results discussed in detail. The advantages of sensitivity, accuracy, and robustness made it a powerful tool for emerging mycotoxin monitoring and dietary exposure assessment.

(±)-Alternamgin, a Pair of Enantiomeric Polyketides, from the Endophytic Fungi Alternaria sp. MG1

A pair of enantiomeric polyketides, (+)- and (-)-alternamgin (1), featuring an unprecedented 6/6/6/6/5/6/6 seven ring backbone, were isolated from the endophytic fungi Alternaria sp. MG1. The relative configuration of 1 was determined using X-ray diffraction, and the absolute configurations of (±)-1 were confirmed by comparing the experimental and calculated ECD data. Plausible biosynthetic pathways for 1 were proposed. Compound (-)-1 exhibited moderate necrosis rates to Hela and HepG2 cells, but (+)-1 only showed similar necrosis rates to HepG2 cells.

Alternaria mycotoxins in grains from Albania: alternariol, alternariol monomethyl ether, tenuazonic acid and tentoxin

The presence of four Alternaria toxins in maize and wheat harvested in 2014 and 2015 in Albania was investigated. In total, 45 samples of maize and 71 samples of wheat were collected from the country’s main producing regions. The presence of alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA) and tentoxin (TTX) was studied by an LC-MS/MS method. The incidence of Alternaria toxins in maize was 45.2% in the year 2014 and 7.1% in 2015, and the contamination rate in wheat was 82.9% in 2014 and 86.1% in 2015. Considering maize and wheat samples together, 65.2 and 64.0% of samples were contaminated by Alternaria toxins in the harvesting years 2014 and 2015, respectively. The occurrence rate was much higher in wheat than in maize, but the concentrations were higher in maize. The highest concentration of total Alternaria toxins in maize was 1,283 μg/kg (mean 243.0 μg/kg, median 110.2 μg/kg), while the maximum concentration in wheat was 175.7 μg/kg (mean 29.9 μg/kg, median 16.5 μg/kg). TeA was the major Alternaria mycotoxin detected. It was found in 70 out of 116 samples (60.3%). Chronic exposure of the adult population in Albania to Alternaria toxins through cereal consumption was assessed by the estimated daily intake (EDI) taking into account daily consumption of wheat and maize of 380 and 4.9 g, respectively. The main contribution to chronic dietary exposure was by TeA originating from wheat, with EDIs of 88.6-94.1 ng/kg body weight (bw) per day in 2014 and 152.7-155.5 ng/kg bw per day in 2015. TTX EDIs were 7.8- 34.0 and 10.6-38.7 ng/kg bw per day in 2014 and 2015, respectively. The contribution of AOH and AME originating from wheat was 0-31.7 ng/kg bw per day. The contribution of Alternaria toxins through maize consumption was significantly lower.

Development of a QuEChERS-Based UHPLC-MS/MS Method for Simultaneous Determination of Six Alternaria Toxins in Grapes

A simple and reliable analytical method for the simultaneous determination of alternariol (AOH), altenuene (ALT), tentoxin (TEN), altenusin (ALS), tenuazonic acid (TeA), and alternariol monomethyl ether (AME) in grapes was developed by ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure with the extraction by acetonitrile and purification by sodium chloride (0.5 g) and anhydrous magnesium sulfate (0.5 g) was established to recover the six Alternaria toxins. After validation by determining the linearity (R² > 0.99), recovery (77.8–101.6%), sensitivity (limit of detection in the range of 0.03–0.21 μg kg⁻¹, and limit of quantification in the range of 0.09–0.48 μg kg⁻¹), and precision (relative standard deviation (RSD) ≤ 12.9%), the analytical method was successfully applied to reveal the contamination state of Alternaria toxins in grapes. Among 56 grape samples, 40 (incidence of 71.4%) were contaminated with Alternaria toxins. TEN was the most frequently found mycotoxin (37.5%), with a concentration range of 0.10–1.64 μg kg⁻¹, followed by TeA (28.6%) and AOH (26.8%). ALT (10.7%), AME (3.6%), and ALS (5.4%) were also detected in some samples. To the best of our knowledge, this is the first report about the Alternaria toxins contamination in grapes in China.

Occurrence of emerging mycotoxins in cereals and cereal-based products from the Korean market using LC-MS/MS

The present study aimed to investigate the occurrence of emerging mycotoxins in cereals (n = 61) and cereal-based products (n = 36) collected from Korean market. First of all, using the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction method, and ultrahigh-pressure liquid chromatography (UPLC) with triple quadruple tandem mass spectrometry (MS/MS), we developed a simple and fast method for quantitative determination of eight emerging mycotoxins including alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN), beauvericin (BEA) and enniatins (ENs; ENA, ENA1, ENB and ENB1). The developed analytical method was validated in parameters of linearity, precision and accuracy. For UPLC-MS/MS analysis, the recoveries of emerging mycotoxins from spiked samples at three concentration levels ranged from 82.7% to 108.8% with RSDs between 0.4% and 14.7%. Analytical methods were applied to determine the contamination of mycotoxins in cereal and cereal-based product samples. Sixty-three of the total 97 samples were contaminated with at least one emerging mycotoxin. The maximum number of emerging mycotoxins observed in a single sample was six out of eight analytes. The highest level of contamination was detected in cereal at 70.9 μg/kg for alternariol monomethyl ether (AME). However, currently there is no international standard for emerging mycotoxins in food. Accordingly, it is necessary to establish a database of emerging mycotoxins contamination through continuous monitoring.

Co-culture of the fungus Fusarium tricinctum with Streptomyces lividans induces production of cryptic naphthoquinone dimers

Co-cultivation of the endophytic fungus Fusarium tricinctum with Streptomyces lividans on solid rice medium led to the production of four new naphthoquinone dimers, fusatricinones A–D (1–4), and a new lateropyrone derivative, dihydrolateropyrone (5), that were not detected in axenic fungal controls. In addition, four known cryptic compounds, zearalenone (7), (−)-citreoisocoumarin (8), macrocarpon C (9) and 7-hydroxy-2-(2-hydroxypropyl)-5-methylchromone (10), that were likewise undetectable in extracts from fungal controls, were obtained from the co-culture extracts. The known antibiotically active compound lateropyrone (6), the depsipeptides enniatins B (11), B1 (12) and A1 (13), and the lipopeptide fusaristatin A (14), that were present in axenic fungal controls and in co-culture extracts, were upregulated in the latter. The structures of the new compounds were elucidated by 1D and 2D NMR spectra as well as by HRESIMS data. The relative and absolute configuration of dihydrolateropyrone (5) was elucidated by TDDFT-ECD calculations.

Naphthoquinone dimers from co-culture of Fusarium tricinctum with Streptomyces lividans.

In vitro characterization of hepatic toxicity of Alternaria toxins

Alternaria mycotoxins are secondary fungal metabolites which can contaminate food and feed. They are produced by Alternaria species with alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), and tentoxin (TEN) as the main representatives for Alternaria mycotoxins in food. Once passing the intestinal barrier, Alternaria toxins can reach the liver to exert yet uncharacterized molecular effects. Therefore, hepatic in vitro systems were used to examine selected Alternaria mycotoxins for their induction of metabolism-dependent cytotoxicity, phosphorylation of the histone H2AX as a surrogate marker for DNA double-strand breaks, and relevant marker genes for hepatotoxicity. Analysis of cell viability as well as the induction of H2AX phosphorylation in the hepatocarcinoma cell line HepG2 revealed a detoxification of 100 μmol/l AME and AOH by pre-treatment with S9 liver homogenate as shown by a decrease in cytotoxicity and H2AX histone phosphorylation to levels observed in control cells. Concentrations up to 100 μmol/l TeA and TEN did not induce H2AX phosphorylation whether metabolized or not. In the metabolically competent human hepatoma cell line HepaRG, no cytotoxicity of Alternaria toxins occurred even at high concentrations up to 100 μmol/l, which indicates a low cytotoxic potential. Induction of gene expression associated with liver toxicity was analyzed by quantitative real-time PCR using a specific hepatotoxicity PCR array in HepaRG cells: here, an evidence was found that 50 μmol/l of AOH, AME, TeA, and TEN might be associated with hepatotoxic effects, necrosis, and the development of diseases like cholestasis and phospholipidosis.

A Review on the Synthesis and Bioactivity Aspects of Beauvericin, a Fusarium Mycotoxin

Beauvericin (BEA) is an emerging Fusarium mycotoxin that contaminates food and feeds globally. BEA biosynthesis is rapidly catalyzed by BEA synthetase through a nonribosomal, thiol-templated mechanism. This mycotoxin has cytotoxicity and is capable of increasing oxidative stress to induce cell apoptosis. Recently, large evidence further shows that this mycotoxin has a variety of biological activities and is being considered a potential candidate for medicinal and pesticide research. It is noteworthy that BEA is a potential anticancer agent since it can increase the intracellular Ca²⁺ levels and induce the cancer cell death through oxidative stress and apoptosis. BEA has exhibited effective antibacterial activities against both pathogenic Gram-positive and Gram-negative bacteria. Importantly, BEA exhibits an effective capacity to inhibit the human immunodeficiency virus type-1 integrase. Moreover, BEA can simultaneously target drug resistance and morphogenesis which provides a promising strategy to combat life-threatening fungal infections. Thus, in this review, the synthesis and the biological activities of BEA, as well as, the underlying mechanisms, are fully analyzed. The risk assessment of BEA in food and feed are also discussed. We hope this review will help to further understand the biological activities of BEA and cast some new light on drug discovery.

Synthesis and Structural Identification of a Biaryl Ether-Linked Zearalenone Dimer

A new dimer of the food-relevant mycotoxin zearalenone was isolated after electrochemical and chemical oxidation. The structure was determined as a 16-O-15'-biaryl ether-linked dimer based on spectroscopic analyses (¹H- and ¹³C-NMR, COSY, HMBC, and HSQCAD) and high-resolution mass spectrometry analysis (Q-TOF).

Comparative in vitro cytotoxicity of the emerging Fusarium mycotoxins beauvericin and enniatins to porcine intestinal epithelial cells

The emerging Fusarium mycotoxins beauvericin (BEA) and enniatin (ENN) A, ENN A1, ENN B and ENN B1 gain increasing interest due to their highly prevalent contamination of cereals and cereal products. After oral intake, the gastro-intestinal tract is the first possible site of interaction. In the present in vitro study, the relative cytotoxicity of these mycotoxins towards proliferating and differentiated intestinal porcine epithelial cells of the jejunum (IPEC-J2) was evaluated using flow cytometric viability analysis. IPEC-J2 cells showed the highest sensitivity to BEA and ENN A. In proliferating cells, incubation for 24h with 10 μM BEA caused complete disruption, while the viability percentage declined to 32% after 24h of incubation with 10 μM ENN A. ENN A1 and ENN B1 were less cytotoxic with 87% and 93% viable cells after 24h of incubation with 10 μM ENN A1 and B1, respectively. ENN B was the least cytotoxic since incubation at concentrations up to 100 μM resulted in 83% viable proliferating cells. The same trend was observed for differentiated cells. The limited in vitro cytotoxic effect of ENN B on intestinal cells corroborates previous in vivo findings in broiler chicken in which dietary ENN B had minimal effect on intestinal morphometry.

Diversity and fate of fungal metabolites during the preparation of oshikundu, a Namibian traditional fermented beverage

Sorghum and pearl millet, ingredients for the popular Namibian traditional fermented beverage oshikundu, are prone to fungal infection, raising concerns for consumer health from mycotoxin exposure. This study aimed at determining the diversity of fungal metabolites in street-vended ingredients and their transfer rates into oshikundu. A total of 105 samples (40 sorghum malt, 40 pearl millet, 25 oshikundu) were analysed for 700 fungal, bacterial and plant metabolites, using liquid chromatography-tandem mass spectrometry. Of 98 quantified metabolites, 84 were fungal, some being mycotoxins. Aspergillus metabolites were most prevalent (50%, n=42), including aflatoxins, aflatoxin precursors, cyclopiazonic acid and 3-nitropropionic acid from Aspergillus flavus; helvolic acid, gliotoxin and fumiquinazolines from Aspergillus fumigatus and cytochalasin E, patulin and tryptoquivalines from Aspergillus clavatus. High levels of up to 2,280 μg/kg for cyclopiazonic acid and 11,900 μg/kg for 3-nitropropionic acid were quantified in sorghum malts. Other metabolites included fumonisins, curvularin, alternariol and dihydroergosine produced by Fusarium, Penicillium, Alternaria and Claviceps genera, respectively. European Union legislated mycotoxins occurred in cereals at a prevalence range of 3-75%, while none were quantifiable in oshikundu. Aflatoxin B1 was quantified in pearl millet meals (13%) and sorghum malts (50%), with 15% sorghum malts having levels above the European Union regulatory limit of 5 μg/kg. Fumonisin B1 was quantified in pearl millet meals (50%) and sorghum malts (75%) at maximum levels of 3,060 μg/kg and 123 μg/kg respectively, and levels in 5% pearl millet meals were above the European Union regulatory limit of 2,000 μg/kg. Zearalenone and ochratoxin A were quantified in the cereals at levels below European Union regulatory limits. For most metabolites quantifiable in oshikundu, transfer rates from cereals to oshikundu were above 50%, necessitating the use of good quality ingredients for preparing oshikundu and assessment of consumer exposure to mycotoxins.

Multi-mycotoxin screening of feed and feed raw materials from Africa

As animal feed is prone to infestation with mycotoxin-producing fungi, mycotoxin contamination of feed should be monitored. Here, we report a multi-mycotoxin survey of feed samples from Africa. We determined the concentrations of aflatoxins, fumonisins, deoxynivalenol, T-2 toxin, zearalenone and ochratoxin A in 1,045 samples of finished feed and feed raw materials (maize, maize silage, other cereals, etc.) from South Africa and 318 samples from Algeria, Tunisia, Morocco, Senegal, Côte d’Ivoire, Nigeria, Ghana, Namibia, Uganda, Kenya, Tanzania, Zambia and Madagascar. We compared the measured mycotoxin concentrations to regulatory limits or guidance values that are in effect in the European Union and analysed the co-occurrence of these mycotoxins. To determine the occurrence of other fungal secondary metabolites, a subset of the samples was analysed using a multi-analyte liquid chromatography tandem mass spectrometry-based method for the simultaneous detection of over 700 fungal metabolites. We found that 33.3% of maize samples and 54.4% of finished feed samples from Senegal, Côte d’Ivoire, Nigeria, Ghana, Namibia, Uganda, Kenya and Tanzania exceeded the European regulatory limit of 20 ng/g aflatoxins. The Fusarium mycotoxins zearalenone, fumonisins and deoxynivalenol were prevalent in all commodities from all countries, but concentrations were in most cases below European guidance values. Concentrations of deoxynivalenol and zearalenone were correlated. Several other Fusarium metabolites occurred frequently (e.g. moniliformin, beauvericin, aurofusarin) or in high concentrations (e.g. aurofusarin, fusaproliferin). Furthermore, high levels of diplodiatoxin were occasionally detected in samples from South Africa and the Alternaria metabolite tenuazonic acid was prevalent and reached high concentrations. In conclusion, aflatoxins frequently occurred in African feed samples in potentially unsafe concentrations. While Fusarium mycotoxins mostly occurred in concentrations below European guidance values, a correlation between deoxynivalenol and zearalenone concentrations suggests that toxicological interactions of these compounds deserve attention. Several less investigated fungal secondary metabolites occurred frequently or reached high concentrations.

Toxicity Assay for Citrinin, Zearalenone and Zearalenone-14-Sulfate Using the Nematode Caenorhabditis elegans as Model Organism

To keep pace with the rising number of detected mycotoxins, there is a growing need for fast and reliable toxicity tests to assess potential threats to food safety. Toxicity tests with the bacterial-feeding nematode Caenorhabditis elegans as the model organism are well established. In this study the C. elegans wildtype strain N2 (var. Bristol) was used to investigate the toxic effects of the food-relevant mycotoxins citrinin (CIT) and zearalenone-14-sulfate (ZEA-14-S) and zearalenone (ZEA) on different life cycle parameters including reproduction, thermal and oxidative stress resistance and lifespan. The metabolization of the mycotoxins by the nematodes in vivo was investigated using HPLC-MS/MS. ZEA was metabolized in vivo to the reduced isomers α-zearalenol (α-ZEL) and β-ZEL. ZEA-14-S was reduced to α-/β-ZEL-14-sulfate and CIT was metabolized to mono-hydroxylated CIT. All mycotoxins tested led to a significant decrease in the number of nematode offspring produced. ZEA and CIT displayed negative effects on stress tolerance levels and for CIT an additional shortening of the mean lifespan was observed. In the case of ZEA-14-S, however, the mean lifespan was prolonged. The presented study shows the applicability of C. elegans for toxicity testing of emerging food mycotoxins for the purpose of assigning potential health threats.

Chemotaxonomy of Mycotoxigenic Small-Spored Alternaria Fungi - Do Multitoxin Mixtures Act as an Indicator for Species Differentiation?

Necrotrophic as well as saprophytic small-spored Alternaria (A.) species are annually responsible for major losses of agricultural products, such as cereal crops, associated with the contamination of food and feedstuff with potential health-endangering Alternaria toxins. Knowledge of the metabolic capabilities of different species-groups to form mycotoxins is of importance for a reliable risk assessment. 93 Alternaria strains belonging to the four species groups Alternaria tenuissima, A. arborescens, A. alternata, and A. infectoria were isolated from winter wheat kernels harvested from fields in Germany and Russia and incubated under equal conditions. Chemical analysis by means of an HPLC-MS/MS multi-Alternaria-toxin-method showed that 95% of all strains were able to form at least one of the targeted 17 non-host specific Alternaria toxins. Simultaneous production of up to 15 (modified) Alternaria toxins by members of the A. tenuissima, A. arborescens, A. alternata species-groups and up to seven toxins by A. infectoria strains was demonstrated. Overall tenuazonic acid was the most extensively formed mycotoxin followed by alternariol and alternariol mono methylether, whereas altertoxin I was the most frequently detected toxin. Sulfoconjugated modifications of alternariol, alternariol mono methylether, altenuisol and altenuene were frequently determined. Unknown perylene quinone derivatives were additionally detected. Strains of the species-group A. infectoria could be segregated from strains of the other three species-groups due to significantly lower toxin levels and the specific production of infectopyrone. Apart from infectopyrone, alterperylenol was also frequently produced by 95% of the A. infectoria strains. Neither by the concentration nor by the composition of the targeted Alternaria toxins a differentiation between the species-groups A. alternata, A. tenuissima and A. arborescens was possible.

Genome Sequence of the Emerging Mycotoxin-Producing Filamentous Fungus Fusarium tricinctum Strain INRA104

The genome of the phytopathogenic fungus Fusarium tricinctum strain INRA104 was sequenced at a fold-coverage of more than 500×. This led to 23 scaffolds, including one scaffold for the mitochondrial genome, for a total genome size of 42.8 Mb, with an average GC content of 45% and 13,387 predicted genes.

The genome of the phytopathogenic fungus Fusarium tricinctum strain INRA104 was sequenced at a fold-coverage of more than 500×. This led to 23 scaffolds, including one scaffold for the mitochondrial genome, for a total genome size of 42.8 Mb, with an average GC content of 45% and 13,387 predicted genes.

Urinary levels of enniatin B and its phase I metabolites: First human pilot biomonitoring study

Enniatins (Enns) are mycotoxins produced by Fusarium spp. and are widely distributed contaminants of cereals and derivate products. Among the different identified enniatins, Enn B is the most relevant analogue in cereals in Europe. Therefore, the aim of this study was to investigate for the first time the occurrence of Enn B and Enn B phase I metabolites in 300 human urine samples throughout an ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) methodology. Three different sample preparation procedures were evaluated and salting-out liquid-liquid extraction showed satisfactory validation results. Enn B was quantified in 83.7% of samples ranging from 0.006 to 0.391 ng/mL (average content: 0.016 ng/mL). In line with the in vitro observations with human liver microsomes, in the here analyzed samples the Enn B monooxygenated, N-demethylated and dioxygenated metabolites were tentatively found in 87.7%, 96.3% and 6.7% of samples. The data of this pilot biomonitoring survey indicate a frequent intake of enniatins in Italy, supporting further toxicological studies to provide better basis for understanding their potential effects in humans.

Risks to human and animal health related to the presence of moniliformin in food and feed

Moniliformin (MON) is a mycotoxin with low molecular weight primarily produced by Fusarium fungi and occurring predominantly in cereal grains. Following a request of the European Commission, the CONTAM Panel assessed the risk of MON to human and animal health related to its presence in food and feed. The limited information available on toxicity and on toxicokinetics in experimental and farm animals indicated haematotoxicity and cardiotoxicity as major adverse health effects of MON. MON causes chromosome aberrations in vitro but no in vivo genotoxicity data and no carcinogenicity data were identified. Due to the limitations in the available toxicity data, human acute or chronic health‐based guidance values (HBGV) could not be established. The margin of exposure (MOE) between the no‐observed‐adverse‐effect level (NOAEL) of 6.0 mg/kg body weight (bw) for cardiotoxicity from a subacute study in rats and the acute upper bound (UB) dietary exposure estimates ranged between 4,000 and 73,000. The MOE between the lowest benchmark dose lower confidence limit (for a 5% response ‐ BMDL₀₅) of 0.20 mg MON/kg bw per day for haematological hazards from a 28‐day study in pigs and the chronic dietary human exposure estimates ranged between 370 and 5,000,000 for chronic dietary exposures. These MOEs indicate a low risk for human health but were associated with high uncertainty. The toxicity data available for poultry, pigs, and mink indicated a low or even negligible risk for these animals from exposure to MON in feed at the estimated exposure levels under current feeding practices. Assuming similar or lower sensitivity as for pigs, the CONTAM Panel considered a low or even negligible risk for the other animal species for which no toxicity data suitable for hazard characterisation were identified. Additional toxicity studies are needed and depending on their outcome, the collection of more occurrence data on MON in food and feed is recommended to enable a comprehensive human risk assessment.

From malt to wheat beer: A comprehensive multi-toxin screening, transfer assessment and its influence on basic fermentation parameters

The aim was to determine the mycotoxin transfer rate into beer during a semi-industrial production process and the effect of fungicide treatment in the field on mycotoxins concentrations in beer. To ensure the usual practical agronomical conditions, sample A was treated with fungicide Prosaro® 250, and sample B was infected with Fusarium culmorum spores, in order to obtain infected malt. Malt was produced using standard procedure and beer was produced in a semi-industrial unit. During fermentation measurement of sugars (maltotriose and maltose), glycerol and ethanol content was performed on a daily basis. Multiple toxins were determined in malt and beer. Deoxynivalenol (DON), its modified plant metabolite DON-3-glucoside (DON-glucoside), brevianamide F, tryptophol, linamarin, lotaustralin, culmorin (CUL), 15-hydroxy-CUL and 5-hydroyx-CUL were detected in all samples. Results indicate that F. culmorum infection did not influence the fermentation process or the alcohol concentration.

Toxicodynamics of Mycotoxins in the Framework of Food Risk Assessment-An In Silico Perspective

Mycotoxins severely threaten the health of humans and animals. For this reason, many countries have enforced regulations and recommendations to reduce the dietary exposure. However, even though regulatory actions must be based on solid scientific knowledge, many aspects of their toxicological activity are still poorly understood. In particular, deepening knowledge on the primal molecular events triggering the toxic stimulus may be relevant to better understand the mechanisms of action of mycotoxins. The present work presents the use of in silico approaches in studying the mycotoxins toxicodynamics, and discusses how they may contribute in widening the background of knowledge. A particular emphasis has been posed on the methods accounting the molecular initiating events of toxic action. In more details, the key concepts and challenges of mycotoxins toxicology have been introduced. Then, topical case studies have been presented and some possible practical implementations of studying mycotoxins toxicodynamics have been discussed.

Chronic Dietary Intake of Enniatin B in Broiler Chickens Has Low Impact on Intestinal Morphometry and Hepatic Histology, and Shows Limited Transfer to Liver Tissue

The Fusarium mycotoxin enniatin B (ENN B) is a so-called emerging mycotoxin frequently contaminating poultry feed. To investigate the impact of chronic ENN B exposure on animal health, broiler chickens were fed either a diet naturally contaminated with ENN B (2352 µg/kg) or a control diet (135 µg/kg) for 2, 7, 14, or 21 days. ENN B concentrations were determined in plasma and liver using a validated ultra-high performance liquid chromatography—tandem mass spectrometry UHPLC-MS/MS method. Liver was evaluated histologically, and the villus length and crypt depth of the duodenum, jejunum, and ileum were measured. Histopathology of the livers did not reveal major abnormalities. Feeding an ENN B-contaminated diet could possibly inhibit the proliferation of enterocytes in the duodenal crypts, but did not affect villus length, crypt depth, or villus length-crypt depth ratio of the jejunum and ileum. ENN B levels in plasma and liver were significantly higher in the ENN B-fed group and ranged between <25–264 pg/mL and <0.05–0.85 ng/g, respectively. ENN B carry-over rates from feed to liver tissue were 0.005–0.014% and 0.034–0.109% in the ENN B and control group, respectively. Carry-over rates were low and indicated a limited contribution of poultry tissue-derived products to the total dietary ENN B intake for humans. The above results support the opinion of the European Food Safety Authority stating that adverse health effects from ENN B in broiler chickens are unlikely.