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Mycotoxin emergence and co-occurrence trends in Canadian grains are dynamic and evolving in response to changing weather patterns within each growing season. The mycotoxins deoxynivalenol and zearalenone are the dominant mycotoxins detected in grains grown in Eastern Canada. Two potential emerging mycotoxins of concern are sterigmatocystin, produced by Aspergillus versicolor, and diacetoxyscirpenol, a type A trichothecene produced by a number of Fusarium species. In response to a call from the 83rd Joint Expert Committee on Food Additives and Contaminants, we conducted a comprehensive survey of samples from cereal production areas in Ontario, Canada. Some 159 wheat and 160 corn samples were collected from farms over a three-year period. Samples were extracted and analyzed by LC-MS/MS for 33 mycotoxins and secondary metabolites. Ergosterol was analyzed as an estimate of the overall fungal biomass in the samples. In wheat, the ratio of DON to its glucoside, deoxynivalenol-3-glucoside (DON-3G), exhibited high variability, likely attributable to differences among cultivars. In corn, the ratio was more consistent across the samples. Sterigmatocystin was detected in some wheat that had higher concentrations of ergosterol. Diacetoxyscirpenol was not detected in either corn or wheat over the three years, demonstrating a low risk to Ontario grain. Overall, there was some change to the mycotoxin profiles over the three years for wheat and corn. Ongoing surveys are required to reassess trends and ensure the safety of the food value chain, especially for emerging mycotoxins. [ABSTRACT FROM AUTHOR]

Trichothecenes produced by Fusarium species are commonly detected in oats. However, the ratios of the concentrations of free trichothecenes and their conjugates and how they are impacted by different interacting environmental conditions are not well documented. This study aims to examine the effect of water activity (0.95 and 0.98 aw) and temperature (20 and 25 °C) stress on the production of T-2 and HT-2 toxins, deoxynivalenol and their conjugates, as well as diacetoxyscirpenol (DAS). Multiple mycotoxins were detected using liquid chromatography–tandem mass spectrometry from 64 contaminated oat samples. The highest concentrations of HT-2-glucoside (HT-2-Glc) were observed at 0.98 aw and 20 °C, and were higher than other type A trichothecenes in the natural oats' treatments. However, no statistical differences were found between the mean concentrations of HT-2-Glc and HT-2 toxins in all storage conditions analysed. DAS concentrations were generally low and highest at 0.95 aw and 20 °C, while deoxynivalenol-3-glucoside levels were highest at 0.98 aw and 20 °C in the naturally contaminated oats. Emerging mycotoxins such as beauvericin, moniliformin, and enniatins mostly increased with a rise in water activity and temperature in the naturally contaminated oats treatment. This study reinforces the importance of storage aw and temperature conditions in the high risk of free and modified toxin contamination of small cereal grains. [ABSTRACT FROM AUTHOR]

Mycotoxin emergence and co-occurrence trends in Canadian grains are dynamic and evolving in response to changing weather patterns within each growing season. The mycotoxins deoxynivalenol and zearalenone are the dominant mycotoxins detected in grains grown in Eastern Canada. Two potential emerging mycotoxins of concern are sterigmatocystin, produced by Aspergillus versicolor, and diacetoxyscirpenol, a type A trichothecene produced by a number of Fusarium species. In response to a call from the 83rd Joint Expert Committee on Food Additives and Contaminants, we conducted a comprehensive survey of samples from cereal production areas in Ontario, Canada. Some 159 wheat and 160 corn samples were collected from farms over a three-year period. Samples were extracted and analyzed by LC-MS/MS for 33 mycotoxins and secondary metabolites. Ergosterol was analyzed as an estimate of the overall fungal biomass in the samples. In wheat, the ratio of DON to its glucoside, deoxynivalenol-3-glucoside (DON-3G), exhibited high variability, likely attributable to differences among cultivars. In corn, the ratio was more consistent across the samples. Sterigmatocystin was detected in some wheat that had higher concentrations of ergosterol. Diacetoxyscirpenol was not detected in either corn or wheat over the three years, demonstrating a low risk to Ontario grain. Overall, there was some change to the mycotoxin profiles over the three years for wheat and corn. Ongoing surveys are required to reassess trends and ensure the safety of the food value chain, especially for emerging mycotoxins.

Trichothecenes produced by Fusarium species are commonly detected in oats. However, the ratios of the concentrations of free trichothecenes and their conjugates and how they are impacted by different interacting environmental conditions are not well documented. This study aims to examine the effect of water activity (0.95 and 0.98 aw) and temperature (20 and 25 °C) stress on the production of T-2 and HT-2 toxins, deoxynivalenol and their conjugates, as well as diacetoxyscirpenol (DAS). Multiple mycotoxins were detected using liquid chromatography–tandem mass spectrometry from 64 contaminated oat samples. The highest concentrations of HT-2-glucoside (HT-2-Glc) were observed at 0.98 aw and 20 °C, and were higher than other type A trichothecenes in the natural oats’ treatments. However, no statistical differences were found between the mean concentrations of HT-2-Glc and HT-2 toxins in all storage conditions analysed. DAS concentrations were generally low and highest at 0.95 aw and 20 °C, while deoxynivalenol-3-glucoside levels were highest at 0.98 aw and 20 °C in the naturally contaminated oats. Emerging mycotoxins such as beauvericin, moniliformin, and enniatins mostly increased with a rise in water activity and temperature in the naturally contaminated oats treatment. This study reinforces the importance of storage aw and temperature conditions in the high risk of free and modified toxin contamination of small cereal grains.

Abstract Background In spring 2021 increasing numbers of cats presenting with severe pancytopenia were noted in United Kingdom (UK). Objective To describe process and outcome of the investigation performed into the outbreak of pancytopenia in cats. Animals Five hundred and eighty client owned cats that presented with severe bi‐ or pancytopenia of unknown cause. Methods Real‐time data collection was performed by an online registration forum available to all veterinary surgeons in UK. Data collected included demographics, clinicopathological findings, diagnostic testing, dietary and drug history, outcome and COVID household status. Mycotoxicological feed analysis was performed on feed samples of 3 diets frequently mentioned in the database and 3 control diets. Results Five hundred and eighty cats presented to 378 veterinary practices were included for analysis. Case fatality rate was 63.3%. Dietary history was available for 544 (93.8%) cats, of which 500 (86%) were fed 1 of 3 diets (which were recalled midinvestigation). 54 (9.3%) cats were not fed a recalled product, with diet information unknown in 26 (4.5%) cats. Analysis of feed samples revealed concentrations of hematotoxic trichothecene T‐2/HT‐2 mycotoxins greater than recommended by the European Commission in 5/7 recalled diet samples but in none of control diet samples. The trichothecene mycotoxin diacetoxyscirpenol (DAS) was detectable in all recalled diet samples but not in any of control samples. Conclusion and Clinical Importance Contaminated‐feed induced trichothecene mycotoxicosis should be considered as a differential diagnosis for pancytopenia in cats.

Background: In spring 2021 increasing numbers of cats presenting with severe pancytopenia were noted in United Kingdom (UK). Objective: To describe process and outcome of the investigation performed into the outbreak of pancytopenia in cats. Animals: Five hundred and eighty client owned cats that presented with severe bi‐ or pancytopenia of unknown cause. Methods: Real‐time data collection was performed by an online registration forum available to all veterinary surgeons in UK. Data collected included demographics, clinicopathological findings, diagnostic testing, dietary and drug history, outcome and COVID household status. Mycotoxicological feed analysis was performed on feed samples of 3 diets frequently mentioned in the database and 3 control diets. Results: Five hundred and eighty cats presented to 378 veterinary practices were included for analysis. Case fatality rate was 63.3%. Dietary history was available for 544 (93.8%) cats, of which 500 (86%) were fed 1 of 3 diets (which were recalled midinvestigation). 54 (9.3%) cats were not fed a recalled product, with diet information unknown in 26 (4.5%) cats. Analysis of feed samples revealed concentrations of hematotoxic trichothecene T‐2/HT‐2 mycotoxins greater than recommended by the European Commission in 5/7 recalled diet samples but in none of control diet samples. The trichothecene mycotoxin diacetoxyscirpenol (DAS) was detectable in all recalled diet samples but not in any of control samples. Conclusion and Clinical Importance: Contaminated‐feed induced trichothecene mycotoxicosis should be considered as a differential diagnosis for pancytopenia in cats. [ABSTRACT FROM AUTHOR]

Abstract Background Certain Fusarium exometabolites have been reported to inhibit seed germination of the cereal-parasitizing witchweed, Striga hermonthica, in vitro. However, it is unknown if these exometabolites will consistently prevent S. hermonthica incidence in planta. The study screened a selection of known, highly phytotoxic Fusarium exometabolites, in identifying the most potent/efficient candidate (i.e., having the greatest effect at minimal concentration) to completely hinder S. hermonthica seed germination in vitro and incidence in planta, without affecting the host crop development and yield. Results In vitro germination assays of the tested Fusarium exometabolites (i.e., 1,4-naphthoquinone, equisetin, fusaric acid, hymeglusin, neosolaniol (Neo), T-2 toxin (T-2) and diacetoxyscirpenol (DAS)) as pre-Striga seed conditioning treatments at 1, 5, 10, 20, 50 and 100 µM, revealed that only DAS, out of all tested exometabolites, completely inhibited S. hermonthica seed germination at each concentration. It was followed by T-2 and Neo, as from 10 to 20 µM respectively. The remaining exometabolites reduced S. hermonthica seed germination as from 20 µM (P 0.05), only DAS completely prevented S. hermonthica incidence. Following a 14-d incubation of DAS in the planting soil substrate, bacterial 16S ribosomal RNA (rRNA) and fungal 18S rRNA gene copy numbers of the soil microbial community were enhanced; which coincided with complete degradation of DAS in the substrate. Metabolic footprinting revealed that the S. hermonthica mycoherbicidal agent, Fusarium oxysporum f. sp. strigae (isolates Foxy-2, FK3), did not produce DAS; a discovery that corresponded with underexpression of key genes (Tri5, Tri4) necessary for Fusarium trichothecene biosynthesis (P

To monitor the contamination of a type A trichothecene, diacetoxyscirpenol (DAS), one monoclonal antibody (mAb) 8A9 with high affinity and specificity was prepared in the present study. The mAb 8A9 showed a 50% inhibition concentration (IC50) of 0.31 μg/L, which is of the highest affinity reported to date. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and lateral flow immunoassay (LFIA) based on mAb 8A9 were developed and exhibited limits of detection as low as 0.65 μg/kg and 100 μg/kg in rice samples, respectively. The molecular recognition mechanism of mAb 8A9 to DAS was explored by molecular docking. The results showed that the hydrophobic amino acids of mAb 8A9 interacted with DAS by forming hydrogen bonds and a pi-sigma bond, which lead to a highly specific recognition of DAS. In summary, we produced one mAb, developed ELISA and LFIA for DAS detection in rice with significantly sensitivity, specificity, accuracy, and precision. [ABSTRACT FROM AUTHOR]

Background: Certain Fusarium exometabolites have been reported to inhibit seed germination of the cereal-parasitizing witchweed, Striga hermonthica, in vitro. However, it is unknown if these exometabolites will consistently prevent S. hermonthica incidence in planta. The study screened a selection of known, highly phytotoxic Fusarium exometabolites, in identifying the most potent/efficient candidate (i.e., having the greatest effect at minimal concentration) to completely hinder S. hermonthica seed germination in vitro and incidence in planta, without affecting the host crop development and yield. Results: In vitro germination assays of the tested Fusarium exometabolites (i.e., 1,4-naphthoquinone, equisetin, fusaric acid, hymeglusin, neosolaniol (Neo), T-2 toxin (T-2) and diacetoxyscirpenol (DAS)) as pre-Striga seed conditioning treatments at 1, 5, 10, 20, 50 and 100 µM, revealed that only DAS, out of all tested exometabolites, completely inhibited S. hermonthica seed germination at each concentration. It was followed by T-2 and Neo, as from 10 to 20 µM respectively. The remaining exometabolites reduced S. hermonthica seed germination as from 20 µM (P < 0. 0001). In planta assessment (in a S. hermonthica-sorghum parasitic system) of the exometabolites at 20 µM showed that, although, none of the tested exometabolites affected sorghum aboveground dry biomass (P > 0.05), only DAS completely prevented S. hermonthica incidence. Following a 14-d incubation of DAS in the planting soil substrate, bacterial 16S ribosomal RNA (rRNA) and fungal 18S rRNA gene copy numbers of the soil microbial community were enhanced; which coincided with complete degradation of DAS in the substrate. Metabolic footprinting revealed that the S. hermonthica mycoherbicidal agent, Fusarium oxysporum f. sp. strigae (isolates Foxy-2, FK3), did not produce DAS; a discovery that corresponded with underexpression of key genes (Tri5, Tri4) necessary for Fusarium trichothecene biosynthesis (P < 0.0001). Conclusions: Among the tested Fusarium exometabolites, DAS exhibited the most promising herbicidal potential against S. hermonthica. Thus, it could serve as a new biocontrol agent for efficient S. hermonthica management. Further examination of DAS specific mode of action against the target weed S. hermonthica at low concentrations (≤ 20 µM), as opposed to non-target soil organisms, is required. [ABSTRACT FROM AUTHOR]

The Chaco wetland is among the most biologically diverse regions in Argentina. In collections of fungi from asymptomatic native grasses (Poaceae) from the wetlands, we identified isolates of Fusarium that were morphologically similar to F. armeniacum, but distinct from it by their production of abundant microconidia. All the isolates had identical, or nearly identical, partial sequences of TEF1 and RPB2. But they were distinct from reference sequences from F. armeniacum and Fusarium species closely related to it. Phylogenetic analysis of 34 full-length housekeeping gene sequences retrieved from whole genome sequences of three Chaco wetland isolates, 29 genes resolved the isolates as an exclusive clade within the F. sambucinum species complex. Based on results of the morphological and phylogenetic analysis, we concluded that the Chaco wetland isolates are a distinct and novel species, herein described as Fusarium chaquense, sp. nov., which is closely related to F. armeniacum. F. chaquense in culture can produce the trichothecenes T-2 and HT-2 toxin, neosolaniol, diacetoxyscirpenol, and monoacetoxyscirpenol, as well as beauvericin and the pigment aurofusarin. Genome sequence analysis also revealed the presence of three previously described loci required for trichothecene biosynthesis. This research represents the first study of Fusarium in a natural ecosystem in Argentina. [ABSTRACT FROM AUTHOR]

To monitor the contamination of a type A trichothecene, diacetoxyscirpenol (DAS), one monoclonal antibody (mAb) 8A9 with high affinity and specificity was prepared in the present study. The mAb 8A9 showed a 50% inhibition concentration (IC50) of 0.31 μg/L, which is of the highest affinity reported to date. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and lateral flow immunoassay (LFIA) based on mAb 8A9 were developed and exhibited limits of detection as low as 0.65 μg/kg and 100 μg/kg in rice samples, respectively. The molecular recognition mechanism of mAb 8A9 to DAS was explored by molecular docking. The results showed that the hydrophobic amino acids of mAb 8A9 interacted with DAS by forming hydrogen bonds and a pi-sigma bond, which lead to a highly specific recognition of DAS. In summary, we produced one mAb, developed ELISA and LFIA for DAS detection in rice with significantly sensitivity, specificity, accuracy, and precision.

For maize grain, which has been important for the forage production of the country over the past two decades, persistent contamination with toxins of fusarium fungi, more often T-2/HT-2 toxins, fumonisins, and more rarely with deoxynivalenol and zearalenone in quantities that pose risks for animal intoxication was showed by enzyme immunoassay. The cases of superintensive accumulation of cyclopiazonic acid, citrinin, mycophenolic acid, and ochratoxin A were revealed. In 2016–2018, for maize grain from four subjects of the Central Federal District of the Russian Federation, a significant prevalence of T-2/HT-2 toxins, deoxynivalenol, and fumonisins with fluctuations in the frequency of occurrence of zearalenone over the years was found; diacetoxyscirpenol was detected in several samples from the Kursk and Voronezh oblasts. Contamination of grain with alternariol in 2016 and 2017 was mild both by frequency (5.3%) and accumulation levels (20–85 μg/kg), but the proportion of samples containing this toxin was 40.7% with a content range of 25–295 μg/kg in the yield of 2018. The influence of soil and climatic factors on the nature of mycotoxin contamination of the maize grain yield, the contribution of fungi belonging to dematiaceous hyphomycetes, and the prevailing variants of combined contamination with fusariotoxins are discussed. [ABSTRACT FROM AUTHOR]

In this report, a UPLC–ESI–MS/MS method for the simultaneous determination of aflatoxins, ochratoxin A, zearalenone, deoxynivalenol, fumonisins, T-2 and HT-2 toxins, fusarenone X, diacetoxyscirpenol, and 3- and 15-acetyldeoxynivalenol in feedstuffs was developed. A quadrupole-time-of-flight mass spectrometer detector (QTOF–MS) operating in full scan mode was combined with the UPLC–ESI–MS/MS system to confirm the identity of detected mycotoxins and to identify other possible microbial metabolites occurring in samples. Sixty-two feed samples from the Spanish market were analyzed. Extraction of metabolites was carried out with acetonitrile-water-formic acid (80:19:1, v/v/v). Method detection and quantification limits and performance criteria set by Commission Regulation (EC) No 401/2006 were fulfilled. Relatively high levels of the main regulated mycotoxins and presence of non-regulated mycotoxins in feed samples were found. This is the first study in which mycotoxins and other microbial metabolites occurring in feed are studied using a UPLC–QTOF–MS system being therefore a reference report. [ABSTRACT FROM AUTHOR]

The trichothecene mycotoxins contaminate cereal grains and have been related to alimentary toxicosis resulted in emetic response. This family of mycotoxins comprises type A to D groups of toxic sesquiterpene chemicals. Diacetoxyscirpenol (DAS), one of the most toxic type A trichothecenes, is considered to be a potential risk for human and animal health by the European Food Safety Authority. Other type A trichothecenes, T-2 toxin and HT-2 toxin, as well as type B trichothecene deoxynivalenol (DON), have been previously demonstrated to induce emetic response in the mink, and this response has been associated with the plasma elevation of neurotransmitters peptide YY (PYY) and serotonin (5-hydroxytryptamine, 5-HT). However, it is found that not all the type A and type B trichothecenes have the capacity to induce PYY and 5-HT. It is necessary to identify the roles of these two emetogenic mediators on DAS-induced emesis. The goal of this study was to determine the emetic effect of DAS and relate this effect to PYY and 5-HT, using a mink bioassay. Briefly, minks were fasted one day before experiment and given DAS by intraperitoneally and orally dosing on the experiment day. Then, emetic episodes were calculated and blood collection was employed for PYY and 5-HT test. DAS elicited robust emetic responses that corresponded to upraised PYY and 5-HT. Blocking the neuropeptide Y2 receptor (NPY2R) diminished emesis induction by PYY and DAS. The serotonin 3 receptor (5-HT3R) inhibitor granisetron totally restrained the induction of emesis by serotonin and DAS. In conclusion, our findings demonstrate that PYY and 5-HT have critical roles in DAS-induced emetic response.

Abstract: A copper‐catalysed (diacetoxyiodo)benzene‐promoted aerobic esterification reaction of acetoacetamides was developed for the synthesis of oxamates, which are useful precursors in synthetic organic chemistry. This practical and mild synthetic approach proceeded at 25 °C under open‐air conditions and afforded methyl 2‐oxo‐2‐(phenylamino)acetates in good to excellent yields combined with C−C σ‐bond cleavage and formal oxidative C−H bond functionalization. A mechanism is proposed. [ABSTRACT FROM AUTHOR]

Fusarium mycotoxins were determined by a multi-mycotoxin liquid chromatography-tandem mass spectrometry (LC-MS/MS) method in cassava ( garri and lafun ) and yam ( amala ) products collected from some selected Nigerian markets. Of the 94 samples analysed, 71% were contaminated with at least one mycotoxin at an incidence rate of 54% ( garri ), 72% ( lafun ), and 82% ( amala ). Deoxynivalenol which ranged between 35 and 99 μg/kg was the most prevalent Fusarium mycotoxin in garri with an incidence rate of 38%, while the dominant mycotoxin in lafun (61%, range = 30–392 μg/kg) and amala (68%, range = 29–155 μg/kg) was fumonisin B 2 . Other mycotoxins detected from the food products included fumonisin B 1 and B 3 , zearalenone, 3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, deoxynivalenol-3-glucoside, T-2 toxin, diacetoxyscirpenol, and fusarenon-X. The consumption of these contaminated products may be a possible route of exposure to a cocktail of Fusarium mycotoxins and can cause potential synergistic health effects on the Nigerian population. [ABSTRACT FROM AUTHOR]

The food-borne trichothecene mycotoxins have been documented to cause human and animal food poisoning. Anorexia is a hallmark of the trichothecene mycotoxins-induced adverse effects. Type B trichothecenes have been previously demonstrated to elicit robust anorectic responses, and this response has been directly linked to secretion of the gut satiety hormones cholecystokinin (CCK) and glucagon-like peptide-1 7–36 amide (GLP-1). However, less is known about the anorectic effects and underlying mechanisms of the type A trichothecenes, including T-2 toxin (T-2), HT-2 toxin (HT-2), diacetoxyscirpenol (DAS), neosolaniol (NEO). The purpose of this study was to relate type A trichothecenes T-2, HT-2, DAS and NEO-induced anorectic response to changes plasma concentrations of CCK and GLP-1. Following both oral gavage and intraperitoneal (IP) administration of 1 mg/kg bw T-2, HT-2, DAS and NEO evoked robust anorectic response and secretion of CCK and GLP-1. Elevations of plasma CCK markedly corresponded to anorexia induction by T-2, HT-2, DAS and NEO. Following oral exposure, plasma CCK was peaked at 6 h, 6 h, 2 h, 2 h and lasted up to 24 h, 24 h, > 6 h, > 6 h for T-2, HT-2, DAS and NEO, respectively. IP exposed to four toxins all induced elevation of CCK with peak point and duration at 6 h and > 24 h, respectively. In contrast to CCK, GLP-1 was moderately elevated by these toxins. Following both oral and IP exposure, T-2 and HT-2 evoked plasma GLP-1 elevation with peak point and duration at 2 h and 6 h, respectively. Plasma GLP-1 was peaked at 2 h and still increased at 6 h for IP and oral administration with DAS and NEO, respectively. In conclusion, CCK plays a contributory role in anorexia induction but GLP-1 might play a lesser role in this response. [ABSTRACT FROM AUTHOR]

Trichothecences, secondary metabolites produced by Fusarium, are serious health risks to humans and animals worldwide. Although type A trichothecence-induced food refusal has been observed, the mechanism underlying the anorexia caused by these compounds is not fully understood. In this study, we hypothesized that anorexia induced by type A trichothecenes, including T-2 toxin (T-2), HT-2 toxin (HT-2), diacetoxyscirpenol (DAS), and neosolaniol (NEO), in mice corresponds to the changes in the gut satiety hormones peptide YY3-36 (PYY3-36) and glucose-dependent insulinotropic polypeptide (GIP) in plasma. A well-characterized mouse food refusal model was used in this assay. Oral exposure to or intraperitoneal (ip) injection of 1 mg/kg bw T-2, HT-2, DAS, or NEO resulted in dramatically decreased food intake, and PYY3-36 and GIP concentrations were elevated accordingly. Specifically, the PYY3-36 and GIP concentrations peaked at 2h following oral exposure to these 4 toxins individually, although the durations were not identical. After ip administration of T-2 or HT-2, PYY3-36 significantly increased within 6h. However, no significant difference was found in the DAS and NEO groups. The GIP levels peaked within 2, 2, 0.5, and 0.5 h, respectively, and remained increased up to 6, 6, 2, and 6h, respectively, following T-2, HT-2, DAS, or NEO ip exposure. The increase in GIP was greater than that of PYY3-36 after exposure to the 4 toxins using 2 administration routes. Together, these findings suggest that PYY3-36 and GIP play a role in T-2-, HT-2-, DAS-, and NEO-induced anorexia. [ABSTRACT FROM AUTHOR]

Rainbow trout are highly sensitive to industrially-relevant levels of the feed-borne Fusarium mycotoxin deoxynivalenol (DON), a common contaminant of plant feedstuffs. Feed additives (yeasts, bacteria, enzymes, etc.) are frequently employed as the primary strategy for counteracting the negative effects of mycotoxins on animal performance. However, their application in aquaculture feeds is still largely speculative. A 12-week growth trial with rainbow trout (initial average body weight = 1.8 g/fish) was carried out to assess the efficacy of a commercially available feed additive purportedly effective for preventing the adverse effects of DON. Fish were reared at 16.4 °C and fed a total of eight diets containing graded levels of DON (0.3, 1.0, 1.5 and 2.0 ppm) from naturally contaminated corn with or without the commercial feed additive (CFA). Highly significant linear decreases in weight gain ( P < 0.0001), feed intake ( P < 0.0001) and thermal-unit growth coefficient (TGC, P < 0.0001) were associated with increasing levels of DON in fish fed the diets with or without the CFA. Similarly, regardless of CFA inclusion, rainbow trout fed the experimental diets experienced significant decreases in whole body crude protein (CP, P < 0.01), lipid ( P ≤ 0.05), ash ( P < 0.05) and gross energy (GE, P < 0.01) content and a significant increase in whole body water content ( P < 0.05). Significant linear or quadratic decreases in retained nitrogen (RN; P < 0.0001), recovered energy (RE, P < 0.0001), nitrogen retention efficiency (NRE; P < 0.05) and energy retention efficiency (ERE, P < 0.05) were also observed in response to increasing levels of DON in rainbow trout fed the diets with or without the CFA. There was no significant interaction between DON and CFA (DON × CFA, P > 0.05) for any of the aforementioned parameters indicating that inclusion of the CFA in the diets at the recommended dosage did not alleviate the adverse effects of DON on growth performance and nutrient utilization of rainbow trout. The feed additive used here was developed through extensive research and development with homeotherms; therefore, use in feeds for cold water fish species may be outside the scope of its effectiveness. Additional work is essential to systematically develop novel approaches for mycotoxin mitigation in highly sensitive farmed fish species. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) reduces crop yield and results in contamination of grains with trichothecene mycotoxins. We previously showed that mitochondria play a critical role in the toxicity of a type B trichothecene. Here, we investigated the direct effects of type A and type B trichothecenes on mitochondrial translation and membrane integrity in Saccharomyces cerevisiae. Sensitivity to trichothecenes increased when functional mitochondria were required for growth, and trichothecenes inhibited mitochondrial translation at concentrations, which did not inhibit total translation. In organello translation in isolated mitochondria was inhibited by type A and B trichothecenes, demonstrating that these toxins have a direct effect on mitochondrial translation. In intact yeast cells trichothecenes showed dose-dependent inhibition of mitochondrial membrane potential and reactive oxygen species, but only at doses higher than those affecting mitochondrial translation. These results demonstrate that inhibition of mitochondrial translation is a primary target of trichothecenes and is not secondary to the disruption of mitochondrial membranes.

Eleven isolates of F. poae, originated from wheat grain at 9 locations mainly in Vojvodina, were encompassed by the present study. The greatest number of samples was collected in 2005, in which the climatic conditions favoured a more intensive occurrence of Fusarium ear blight of wheat. In order to determine toxicological potential of this species, cultures of the selected isolates were grown in liquid media (GPY and SPY) on a rotary shaker (180 revolutions min-1), at room temperature (21-26°C) for three days. Crude toxins were isolated from liquid culture filtrates of isolates by the use of ethyl acetate, while quantification of mycotoxins was done by the thin layer chromatography method. A liquid culture of the isolate GZ-LES (F. graminearum) was used as a control for the evaluation of the zearalenone biosynthesis potential. On the other hand, the liquid culture of the isolate KF-38/1 (F. sporotrichioides) was used as a control for both type-A trichothecenes (T-2 toxin and diacetoxyscirpenol - DAS). The obtained results show that F. poae, in contrast to F. graminearum, has no potential for the zearalenone biosynthesis. The presence of DAS was determined only in one isolate of F. poae (MRIZP-666), and in the control isolate of F. sporotrichioides (KF-38/1/R), that were grown in the GPY liquid medium. The T-2 toxin was detected in the isolate MRIZP-666, grown in both media, and in the isolates MRIZP-37 and MRIZP-860, cultured in the GPY and SPY liquid medium, respectively. The control culture KF-38/1/R (F. sporotrichioides) produced the T-2 toxin at the concentration of 4,000 μg L-1. According to the gained information, it can be concluded that the potential of F. poae for the type-A trichothecene biosynthesis was low, as the concentration of DAS or T-2 toxin did not exceed 80 μg L-1 or 240 μg L-1, respectively.

Magnetic solid-phase extraction (m-SPE) is a promising sample preparation approach due to its convenience, speed, and simplicity. For the first time, a rapid and reliable m-SPE approach using magnetic multi-walled carbon nanotubes (m-MWCNTs) as the adsorbent was proposed for purification of type A trichothecenes including T-2 toxins (T2), HT-2 toxins (HT-2), diacetoxyscirpenol (DAS), and neosolaniol (NEO) in coix seed. The m-MWCNTs were synthesized by assembling the magnetic nanoparticles (FeO) with MWCNTs by sonication through an aggregation wrap mechanism, and characterized by transmission electron microscope. Several key parameters affecting the performance of the procedure were extensively investigated including extraction solutions, desorption solvents, and m-MWCNT amounts. Under the optimal sample preparation conditions followed by analysis with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), high sensitivity (limit of quantification in the range of 0.3-1.5 μg kg), good linearity ( R > 0.99), satisfactory recovery (73.6-90.6 %), and acceptable precision (≤2.5 %) were obtained. The analytical performance of the developed method has also been successfully evaluated in real coix seed samples. [ABSTRACT FROM AUTHOR]

A method for the determination of seven trichothecenes, neosolaniol (NEO), diacetoxyscirpenol (DAS), deoxynivalenol (DON), nivalenol (NIV), fusarenon-X (FUS-X), 3-acetyldeoxynivalenol (3-ADON) and 15-acetyldeoxynivalenol (15-ADON), in laboratory rat feed by GC-MS/MS was developed. Sample extraction and purification was performed by an acidified mixture of acetonitrile/water (80–20% v/v). Limits of quantitation (LOQs) were between 1 and 10 μg kg–1for all studied trichothecenes. Eight concentration levels between the LOQ and 100 × LOQ were used for the calibration curves. Matrix-matched calibration was used for quantitation purposes to compensate the detector signal enhancement obtained for all the analytes. The method accuracy was evaluated by recovery assays at three concentration levels, 25, 50 and 100 μg kg–1(n = 9). Recoveries ranged from 62% to 97% and precision, expressed as intra- and inter-day relative standard deviations, was evaluated for all compounds. The validated method was successfully applied to the analysis of 35 laboratory rat feed samples showing mycotoxin contamination in 66% of the samples. DON was the most prevalent trichothecene followed by 15-ADON, NIV and 3-ADON. The maximum DON concentration reached in real samples was 2156 ± 4.3 μg kg–1, while NEO, DAS and FUS-X were not detected in any sample. Multi-contamination by at least two mycotoxins was observed in 17% of the analysed feed samples. [ABSTRACT FROM PUBLISHER]

Fish consumption has been increasing worldwide, mainly due to the availability, access and price in relation to other kinds of meat consumption, such as beef, pork, and poultry. Consequently, some concerns begin to emerge, primarily regarding the quality of fish available in the market. Residues could be present in any product of animal origin causing economic losses and putting into a risk human and animal health. Food contamination by mycotoxins is a risk to human and animal health, and it is responsible for significant economic losses. It's very difficult to prove that a disease is a mycotoxicosis, and even when mycotoxins are detected, it is not easy to show that they are the etiological agents in veterinary pathology or human health problem. In spite of inevitable and widespread, the presence of mycotoxins in feeds of fish cannot be neglected, as revealed by the sight of many researches, field outbreaks reported and pathologies related to mycotoxins, mainly because the toxic effects and safety levels of mycotoxins in the different species of fish are superficially still known. Setting mycotoxin regulations is a complex activity, which involves interested parties and several factors, both of a scientific and socio-economic nature may influence the establishment of mycotoxin limits and regulations. The first limits for mycotoxins were set in the late 1960s for the aflatoxins and by the end of 2003, several countries had developed specific limits for mycotoxins in foodstuffs and feedstuffs, and the number continues to grow, however the residual tolerable of mycotoxins in the fish is still non-existent. [ABSTRACT FROM AUTHOR]

Diacetoxyscirpenol (DAS), a Fusarium mycotoxin belonging to the trichothecene type A mycotoxins, is able to contaminate food and feed worldwide. Only limited information is available regarding the metabolism of DAS. The present study used ultrahigh-performance liquid chromatography-quadrupole/time-of-flight hybrid mass spectrometry (UHPLC-Q/TOF) to investigate the in vitro phase I and II metabolism of DAS by rat, chicken, swine, goat, cow, and human liver microsomes. An extensive metabolization profile of DAS has been observed. A total of seven phase I and three phase II metabolites of DAS were detected. Among the identified molecules, four phase I metabolites (8β-hydroxy-DAS, neosolaniol, 7-hydroxy-DAS, and its epimer) and two phase II metabolites (4-deacetyl-DAS-3-glucuronic acid and 4-deacetyl-DAS-4-glucuronic acid) were identified for the first time. These results indicate that the major metabolic pathways of DAS in vitro were hydrolyzation (M1-M3), hydroxylation (M4-M7), and conjugation (M8-M10). Qualitative differences in phase I and II metabolic profiles of DAS between the five animal species and human were observed. 4-Deacetyl-DAS was the primary metabolite from liver microsomes of all species, especially human. The in vivo metabolism of DAS in rats and chickens after oral administration of DAS was also investigated and compared. The major metabolites for rats and chickens were 4-deacetyl-DAS and 7-hydroxy-DAS. These results will help to gain a more detailed insight into the metabolism and toxicity of DAS among different animal species and human. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Fusarium goolgardi, isolated from the grass tree Xanthorrhoea glauca in natural ecosystems of Australia, is closely related to fusaria that produce a subgroup of trichothecene (type A) mycotoxins that lack a carbonyl group at carbon atom 8 (C-8). Mass spectrometric analysis revealed that F. goolgardi isolates produce type A trichothecenes, but exhibited one of two chemotypes. Some isolates (50%) produced multiple type A trichothecenes, including 4,15-diacetoxyscirpenol (DAS), neosolaniol (NEO), 8-acetylneosolaniol (Ac-NEO) and T-2 toxin (DAS-NEO-T2 chemotype). Other isolates (50%) produced only DAS (DAS chemotype). In the phylogenies inferred from DNA sequences of genes encoding the RNA polymerase II largest (RPB1) and second largest (RPB2) subunits as well as the trichothecene biosynthetic genes (TRI), F. goolgardi isolates were resolved as a monophyletic clade, distinct from other type A trichothecene-producing species. However, the relationships of F. goolgardi to the other species varied depending on whether phylogenies were inferred from RPB1 and RPB2, the 12-gene TRI cluster, the two-gene TRI1-TRI16 locus, or the single-gene TRI101 locus. Phylogenies based on different TRI loci resolved isolates with different chemotypes into distinct clades, even though only the TRI1-TRI16 locus is responsible for structural variation at C-8. Sequence analysis indicated that TRI1 and TRI16 are functional in F. goolgardi isolates with the DAS-NEO-T2 chemotype, but non-functional in isolates with DAS chemotype due to the presence of premature stop codons caused by a point mutation. [ABSTRACT FROM AUTHOR]

This paper reports a new method for the determination of T-2 and HT-2 toxins and their glucosylated derivatives in cereals, and some survey data aimed at obtaining more comprehensive information on the co-occurrence of T-2 and HT-2 toxins and their glucosylated derivatives in naturally contaminated cereal samples. For these purposes, barley samples originating from a Northern Italian area were analysed by LC-HRMS for the presence of T-2, HT-2 and relevant glucosyl derivatives. Quantitative analysis of T-2 and HT-2 glucosides was performed for the first time using a recently made available standard of T-2 glucoside. The glucosyl derivative of HT-2 was detected at levels up to 163 µg kg–1in 17 of the 18 analysed unprocessed barley grains, whereas the monoglucosyl derivative of T-2 toxin was detected in only a few samples and at low µg kg–1levels. The ratio between glucosylated toxins (sum of T-2 and HT-2 glucosides) and native toxins (sum of T-2 and HT-2) ranged from 2% to 283%. Moreover, taking advantage of the possibility of retrospective analysis of full-scan HRMS chromatograms, samples were also screened for the presence of other type-A trichothecenes, namely neosolaniol, diacetoxyscirpenol and their monoglucosyl derivatives, which were detected at trace levels. A subset of nine different samples was subjected to micro-maltation in order to carry out a preliminary investigation on the fate of T-2, HT-2 and relevant glucosides along the malting process. Mycotoxin reduction from cleaned barley to malt was observed at rates ranging from 4% to 87%. [ABSTRACT FROM PUBLISHER]

An LC–MS/MS method was developed and validated for the detection and quantification of 23 mycotoxins in different varieties of sorghum. The method performance characteristics were as follows: suitable linearity ranges for all 23 mycotoxins with p -value >0.05; limits of detection (1.2–50 μg/kg), limits of quantification (2.5–100 μg/kg), repeatability (RSDr, 7–22%), intermediate precision (RSDR, 14–44%) and apparent recovery (0.2–11%, expressed as bias). The method was applied to analyze 10 samples obtained from retail shops in Belgium ( n = 8) and Germany ( n = 2). Nine of the 10 samples (90%) were positive for the following mycotoxins: aflatoxin B 1 (50 μg/kg), alternariol monomethyl ether (

A high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS) method was developed for simultaneous determination of 20 Fusarium toxins (nivalenol, fusarenon-X, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, HT-2 toxin, T-2 toxin, neosolaniol, diacetoxyscirpenol, fumonisin B1, fumonisin B2, fumonisin B3, fumonisin A1, fumonisin A2, fumonisin A3, zearalenone, α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol) in cereals. The separation of 20 Fusarium toxins with good peak shapes was achieved using a pentafluorophenyl column, and Orbitrap MS was able to detect accurately from cereal matrix components within ±0.77 ppm. The samples were prepared using a QuEChERS kit for extraction and a multifunctional cartridge for purification. The linearity, repeatability, and recovery of the method were >0.9964, 0.8%-14.7%, and 71%-106%, respectively. Using this method, an analysis of 34 commercially available cereals detected the presence of deoxynivalenol, 15-acetyl deoxynivalenol, fumonisin B1, fumonisin B2, fumonisin B3, fumonisn A1, fumonisin A2, fumonisin A3, and zearalenone in corn samples with high concentration and frequency. Trichothecenes was detected from wheat samples with high frequency; in particular, the concentration of deoxynivalenol was high. Conversely, α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol were not detected in any of the samples. [ABSTRACT FROM AUTHOR]

Mycotoxins, the toxic products of molds, exposure causes serious adverse health problems in human, animals, and crops. Determining the potential genotoxic effects of these substances is, therefore, of great importance. We have evaluated the genotoxic toxicity of two trichothecenes – diacetoxyscirpenol (DAS) and T-2 toxin – using the wing somatic mutation and recombination test (SMART) in Drosophila melanogaster. The SMART is based on the principle that the loss of heterozygosis of recessive markers located on the left arm of chromosome 3 – multiple wing hairs (mwh) at the map position 0.3 and flare-3 (flr3) at the map position 38.8 – may occur through various mechanisms such as mitotic recombination, mutation, deletion, half-translocation, chromosome loss, and nondisjunction. Both the mycotoxins were administered to third instar larvae (72 ± 4 h old) at concentrations ranging from 5 to 40 μM. Based on our results, DAS and T-2 toxins does not exert genotoxic effects up to a concentration of 40 μM. [ABSTRACT FROM PUBLISHER]