Deoxynivalenol Levels Research Articles

Fusarium culmorum mycotoxin transfer from wheat to malting and brewing products and by-products

The objectives of this study were to establish the impact ofFusarium culmorum infection and fungicide treatment on the occurrence of deoxynivalenol (DON), 3-acetyl deoxynivalenol, T-2 toxin, HT-2 toxin, nivalenol, fusarenon-X, diacetoxyscirpenol and zearalenone in wheat, wheat malt and wort (beer). The concentrations of these compounds were also measured in the germ/rootlets, spent grains and spent yeast because these are the most important by-products and are further used as food or feed additives. Two wheat genotypes were obtained from the Agricultural Institute in Osijek, Croatia. The Osk.110/09 genotype, the genotype more susceptible toFusarium infections, and Lucija, the genotype less susceptible toFusarium, were analysed in this research. Each genotype was treated in four different ways at the field: (A) control, (B) treated with fungicide Prosaro® 250, (C) inoculated withF. culmorum spores and treated with fungicide Prosaro® 250, and (D) inoculated withF. culmorum spores. All samples were malted and brewed according to standard procedures, products and by-products were analysed for the mycotoxins by using LC-MS/MS. Since the majority of trichothecenes are polar molecules, the water after steeping was also analysed with LC-MS/MS. Mycotoxin concentrations were lower in malt samples treated with the fungicide. Elevated mycotoxin concentrations were observed in samples of both genotypes exposed toF. culmorum. Fungicide treatment was observed to suppress mycotoxin production and accumulation. However, samples with notably high mycotoxin concentrations, especially DON, retained elevated mycotoxin concentrations throughout the entire beer production process, even after a six-month storage period. DON proved to be the most frequently occurring mycotoxin in all of the by-products. The highest concentration of this compound was found in the steeping water from sample D (Osk.110/09), at 20,326 μg/l, leaving the spent grains of this sample with no detectable levels of DON.

An eight-year survey of wheat shows distinctive effects of cropping factors on different Fusarium species and associated mycotoxins

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.

A comparative investigation of the effects of feed-borne deoxynivalenol (DON) on growth performance, nutrient utilization and metabolism of detoxification in rainbow trout (Oncorhynchus mykiss) and Nile tilapia (Oreochromis niloticus) fed diets containing different levels of digestible carbohydrates

Increasing evidence suggests that variability in hepatic glucuronidation is a critical determinant of mammalian species-specific sensitivity to the Fusarium mycotoxin deoxynivalenol (DON). Concurrently, ongoing work regarding the effects of DON on fish has led to broad classifications concerning species-specific sensitivity (e.g. rainbow trout are highly sensitive to DON and channel catfish are highly tolerant to DON). This study was designed to determine if sensitivity to DON in fish is related to inherent differences in UDP-glucuronosyltransferase (UDPGT) activity and to evaluate if increased dietary digestible starch content could be an effective strategy to increase glucuronidation capacity. Rainbow trout or Nile tilapia (initial average body weight = 21.9 and 8.1 g/fish, respectively) were fed two series (12 or 24% digestible starch) of three diets containing graded levels of naturally occurring DON (0.1, 0.7 and 1.3 ppm) for 10 weeks. Significant linear decreases in weight gain, thermal-unit growth coefficient (TGC, P ≤ .05), feed efficiency (P < .001), whole body crude protein (CP) content (P < .001), retained nitrogen (RN, P ≤ .05) and nitrogen retention efficiency (NRE, P < .01) were associated with increasing levels of DON in rainbow trout regardless of the dietary digestible starch content. There were no significant effects of DON on any of these parameters in Nile tilapia (P > .05) with the exception of a quadratic increase in NRE (P < .01) in fish fed the diets containing 24% digestible starch. The effect of DON on growth performance and nutrient utilization was not altered by the digestible starch content of the diet (P > .05, DON × digestible starch). A significant quadratic decrease (P ≤ .05) in UDPGT activity was associated with increasing levels of DON in rainbow trout fed the diet containing 12% digestible starch, whereas trout and tilapia fed the diet containing 24% digestible starch experienced significant quadratic or linear increases (P ≤ .05) in UDPGT activity, respectively. However, UDPGT activity was approximately 10-fold higher in rainbow trout than in Nile tilapia. This suggests that UDPGT activity is not responsible for the observed species-specific sensitivity to DON or it is not an appropriate biomarker of DON glucuronidation. A significantly higher relative fold expression of CYP1A in tilapia compared to trout (P = .0001) may offer potential opportunity for future study. We demonstrate for the first time that Nile tilapia are unaffected by practically relevant levels of DON which are detrimental to rainbow trout. This study also extends the current knowledge of DON metabolism and represents an important contribution to the development of efficacious nutritional mycotoxin mitigation strategies.

Contamination of Wheat Cultivated in Various Regions of Poland during 2017 and 2018 Agricultural Seasons with Selected Trichothecenes and Their Modified Forms.

Cross-interaction of antibodies within the immunoaffinity columns used in this study facilitated the simultaneous determination of nivalenol (NIV), deoxynivalenol (DON), their glucoside derivatives (NIV-3G, DON-3G), and 3-acetyl-deoxynivalenol (3-AcDON) in wheat grain harvested in various regions of Poland. In Poland, 2018 was a warm, dry agricultural season, and hence, was relatively less favourable for cereal cultivation than 2017. Data on the natural occurrence of NIV-3G in wheat grain are among the first published in the literature. DON was the most frequently found mycotoxin in the tested samples; the percentage occurrence of DON-positive samples was 92% in 2017 and 61% in 2018. Moreover, DON concentrations were generally higher in 2017 samples (5.2–1670.7 µg/kg) than those in 2018 samples (range 5.0–461.7 µg/kg). A similar pattern was found for DON-3G. However, no statistically significant differences between the samples from the two agricultural seasons were observed for the other three mycotoxins that were analysed, and their concentrations were generally considerably lower. DON was strongly correlated with DON-3G (correlation coefficient r = 0.9558), while NIV was strongly correlated with NIV-3G (r = 0.9442). The percentage occurrence of NIV-3G- and DON-3G-positive samples was 14% in 2017 and 49% in 2018. The NIV-3G/NIV ratio was 5.9–35.7%, while the DON-3G/DON ratio range was 3.2–53.6%. In 2018, wheat samples from Southern Poland exhibited statistically significantly higher levels of DON than those from Northern Poland. The dry and hot summer of 2018 not only reduced wheat yields, but also limited development of Fusarium spp. Therefore, grain harvested that year was generally contaminated with relatively low levels of mycotoxins. Lower levels of DON were also accompanied by lesser amounts of DON-derivatives.

Investigation of the Metabolic Profile and Toxigenic Variability of Fungal Species Occurring in Fermented Foods and Beverage from Nigeria and South Africa Using UPLC-MS/MS.

Fungal species recovered from fermented foods and beverage from Nigeria and South Africa were studied to establish their toxigenic potential in producing an array of secondary metabolites including mycotoxins (n = 49) that could compromise human and animal safety. In total, 385 fungal isolates were grown on solidified yeast extract sucrose agar. Their metabolites were extracted and analyzed via ultra-performance liquid chromatography tandem mass spectrometry. To examine the grouping of isolates and co-occurrence of metabolites, hierarchal clustering and pairwise association analysis was performed. Of the 385 fungal strains tested, over 41% were toxigenic producing different mycotoxins. A. flavus and A. parasiticus strains were the principal producers of aflatoxin B1 (27–7406 µg/kg). Aflatoxin B1 and cyclopiazonic acid had a positive association. Ochratoxin A was produced by 67% of the A. niger strains in the range of 28–1302 µg/kg. The sterigmatocystin producers found were A. versicolor (n = 12), A. amstelodami (n = 4), and A. sydowii (n = 6). Apart from P. chrysogenum, none of the Penicillium spp. produced roquefortine C. Amongst the Fusarium strains tested, F. verticillioides produced fumonisin B1 (range: 77–218 µg/kg) meanwhile low levels of deoxynivalenol were observed. The production of multiple metabolites by single fungal species was also evident.

Dietary Deoxynivalenol Exposure Assessment in University Students from Japan.

This study was conducted to give a preliminary estimation of deoxynivalenol (DON) dietary exposure in Japanese university students (n = 30, aged 22–25 years) using a biomarker approach and to examine the correlation between wheat food intake and DON exposure levels. Spot urine samples were collected from 30 students of Azabu University, Tokyo. Urine samples were treated with enzyme digestion (for total DON measurement) and without (for unconjugated DON analysis) before clean-up using an immuno-affinity column and analysis using an LC-MS method, with a 13C15- DON internal standard used for accurate quantification. The limit of detection for this method is 0.5 ng/mL urine. The geometric mean (95% CI) of DON concentration was 2.03 (1.64 – 6.87) ng per mL urine. Ninety of the urine samples had detectable levels of urinary DON. The DON dietary intake exposure estimation suggested that one out of the 30 subjects had an intake of DON that exceeded Joint FAO/WHO Expert Committee on Food Additives (JECFA) provisional maximum tolerable daily intake (PMTDI) level. Mean ratio of free DON to total DON was determined to be 19%. Wheat intake assessed using a basic food frequent questionnaire method did not show a significant correlation with the urinary DON level.

Survey of Deoxynivalenol Contamination in Agricultural Products in the Chinese Market Using An ELISA Kit.

A total of 328 agricultural product samples highly suspected to be contaminated, from flour companies, feed companies, and livestock farms throughout China, were surveyed for deoxynivalenol (DON) contamination using a self-assembly enzyme-linked immunosorbent assay (ELISA) kit. An ELISA kit for DON was developed with a 4.9 ng mL−1 limit of detection (LOD) in working buffer and a 200 ng g−1 LOD in authentic samples. The DON contamination detection rate was 88.7%, concentrations ranged from 200.9 to 6480.6 ng g−1, and the highest DON contamination was found in distillers’ dried grains with solubles with an average of 3204.5 ng g−1. Wheat bran and wheat were found to be the most commonly contaminated samples, and the corn meal samples had the lowest average DON level. This ELISA kit is a powerful alternative method for the rapid, sensitive, specific, accurate, and high-throughput determination of DON and can meet the maximum requirement levels. This survey suggests that DON contamination in the Chinese market is serious, and the contamination risk deserves attention. Essential preventive measures should be implemented to ensure food safety and human health.

The role of roughage provision on the absorption and disposition of the mycotoxin deoxynivalenol and its acetylated derivatives in calves: from field observations to toxicokinetics.

A clinical case in Belgium demonstrated that feeding a feed concentrate containing considerable levels of deoxynivalenol (DON, 1.13mg/kg feed) induced severe liver failure in 2- to 3-month-old beef calves. Symptoms disappeared by replacing the highly contaminated corn and by stimulating ruminal development via roughage administration. A multi-mycotoxin contamination was demonstrated in feed samples collected at 15 different veal farms in Belgium. DON was most prevalent, contaminating 80% of the roughage samples (mixed straw and maize silage; average concentration in positives: 637 ± 621µg/kg, max. 1818µg/kg), and all feed concentrate samples (411 ± 156µg/kg, max. 693µg/kg). In order to evaluate the impact of roughage provision and its associated ruminal development on the gastro-intestinal absorption and biodegradation of DON and its acetylated derivatives (3- and 15-ADON) in calves, a toxicokinetic study was performed with two ruminating and two non-ruminating male calves. Animals received in succession a bolus of DON (120µg/kg bodyweight (BW)), 15-ADON (50µg/kg BW), and 3-ADON (25µg/kg) by intravenous (IV) injection or per os (PO) in a cross-over design. The absolute oral bioavailability of DON was much higher in non-ruminating calves (50.7 ± 33.0%) compared to ruminating calves (4.1 ± 4.5%). Immediately following exposure, 3- and 15-ADON were hydrolysed to DON in ruminating calves. DON and its acetylated metabolites were mainly metabolized to DON-3-glucuronide, however, also small amounts of DON-15-glucuronide were detected in urine. DON degradation to deepoxy-DON (DOM-1) was only observed to a relevant extent in ruminating calves. Consequently, toxicity of DON in calves is closely related to roughage provision and the associated stage of ruminal development.

Transfer of Deoxynivalenol (DON) through Placenta, Colostrum and Milk from Sows to Their Offspring during Late Gestation and Lactation.

Deoxynivalenol (DON) contamination of feed may result in reduced growth, feed refusal, immunosuppression, and health problems in swine. Piglets can be exposed to DON via placenta before birth and via milk during lactation. The extent of early-life exposure of piglets to DON is, however, not fully known. This study was therefore aimed at investigating DON uptake in sows fed with naturally contaminated diets, DON transfer across placenta during late gestation, and transfer of DON to piglets via colostrum and milk. Forty-four crossbred sows were evaluated from day 93 ± 1 of gestation until weaning of piglets and fed with feed made from naturally DON-contaminated oats at three concentration levels: (1) control (DON < 0.2 mg/kg), (2) DON level 1 (1.4 mg DON/kg), and (3) DON level 2 (1.7 mg DON/kg). The transfer of DON to the piglets was evaluated in 15 sows, with repeated sampling of blood and milk from the sows and blood samples from five piglets of each litter. The piglet/sow plasma DON ratio and milk/plasma (M/P) DON ratio in sows were calculated to estimate the degree of transfer. Piglet/sow plasma ratios were 2.14 at birth, 2.30 within 12–36 h after parturition, 0.08 on day 7, 0.16 on day 21, and 0.20 at weaning. M/P ratios were 0.92, 1.11, 0.94, 1.21, and 0.90, respectively. The results indicate that DON is efficiently transferred across placenta and into milk. However, the low piglet/sow plasma ratios at mid-lactation to weaning indicate that the piglets were most strongly exposed to DON in early life, despite the high M/P ratios and efficient secretion of DON in milk throughout the entire lactation.

Deoxynivalenol screening in wheat‐derived products in Gran Asunción, Paraguay

Abstract Fusarium graminearum is one of the most important pathogens affecting wheat production in Paraguay. This fungus decreases yield and grain quality; the most important consequence is the production of mycotoxins from the trichothecene group, secondary metabolites toxic to humans and other animals. The toxin reported in Paraguay is deoxynivalenol, which has effects on the gastrointestinal tract and immune system. To determine the presence of deoxynivalenol in flour and baked goods, samples of wholemeal flour and white flour, white and wholemeal bread, and bran crackers were carried out in the Gran Asunción Area. The presence of deoxynivalenol was determined by monoclonal antibodies through the use of quantitative test strips. The results were variable and below those established by international standards.Practical applicationsIn the developing countries, the control of the quality and safety of food is practically nonexistent. In Paraguay, there is no legislation on the maximum levels of deoxynivalenol in wheat and derivatives. As this cereal and its derivative products are highly susceptible to contamination by Fusarium and its mycotoxins, it is a priority to initiate controls and establish bases for legislation on maximum acceptable limits in these products. Also highlight the need at country level of the application of high efficiency and sensitive techniques for quantification mycotoxins in food.

Impact of agronomic factors on fusarium mycotoxins in harvested wheat

ABSTRACTThe aim of this study was to model fusarium mycotoxins against agronomic factors in order to identify those that have the greatest impact on mycotoxin levels in harvested wheat. To achieve this, fusarium mycotoxins levels were monitored, and associated agronomic data collected, in approximately 150 English wheat fields/year between 2006 and 2013. Results showed large seasonal variation in fusarium mycotoxin levels, with high levels in 2008 (13% and 29% exceeding legal limit for unprocessed soft wheat intended for human consumption for deoxynivalenol (DON) and zearalenone (ZON), respectively) and 2012 (10% and 15% exceeding legal limit for unprocessed soft wheat intended for human consumption for DON and ZON, respectively) and low levels in 2006 and 2011 (no samples exceeding legal limits for unprocessed soft wheat intended for human consumption for DON or ZON). Analysis of agronomic factors identified previous crop, cultivation and variety as the greatest risk factors. The greatest risk of mycotoxin development in grain was following maize as a previous crop and minimum tillage. The combined effect of these factors gave respective average DON and ZON levels 20 and 14 times higher than other previous crop and cultivation combinations. A newly quantified risk factor was harvest date. A 1-month delay in harvest resulted in a 10 and 25 times greater mean DON and ZON concentration, respectively, when compared to crops harvested around the long-term regional average harvest date. These results highlight the highly seasonal variation in fusarium mycotoxins in wheat and the agronomic factors that should be avoided to minimise fusarium mycotoxin levels in harvested wheat.

Deoxynivalenol Decontamination in Raw and Germinating Barley Treated by Plasma-Activated Water and Intense Pulsed Light

The contamination of barley kernel by Fusarium fungi constitutes a serious problem for malting-related industries. Deoxynivalenol (DON) is a secondary metabolite produced by Fusarium fungi. DON can affect dopaminergic receptors in the human brain; it may cause symptoms such as vomiting, diarrhea, headache, and fever. The aims of this study were to evaluate the DON destruction effect of the intense pulsed light (IPL) and plasma-activated water (PAW) treatments in raw and germinating barley and assess the feasibility for disinfection in the malt industry. Both non-thermal methods degraded DON concentration in germinating barley. IPL treatment significantly reduced (p < 0.05) the DON level of germinating barley samples by 35.5% after 180 pulses in 60 s, and the PAW treatment effectively degraded the DON level by 34.6% in germinating barley in the first 5 min. However, higher barley quality remained for PAW treatment (germination rate: 81–100%) than for the IPL treatment (germination rate: 41–60%). For the raw barley samples, although significant reduction (30.9%) was achieved after 180 pulses of IPL treatment, noticeable quality (germination rate: 20–40%) alteration was observed. Significantly less DON degradation was achieved by the PAW treatment on raw barley than the germinating barley for all times. Overall, these findings suggested that PAW and IPL might potentially be used to reduce DON levels in some malt-related industry applications, and PAW was recommended as a better method than IPL to maintain the barley quality.

Effects of feeding naturally contaminated deoxynivalenol diets to sows during late gestation and lactation in a high-yield specific pathogen-free herd

BackgroundThe most prevalent Fusarium mycotoxin in grains is deoxynivalenol (DON). Contamination of swine feed with DON can result in reduced consumption and poor growth performance. Gestating and lactating sows need sufficient feed intake for fetus development during late gestation and milk production and body maintenance during lactation. Therefore, there is considerable concern in modern piglet production about the effects of DON contamination in sow feed. Most previous studies in sows have been done under experimental conditions, with DON levels ≥2.8 mg/kg feed. The aim of the current field trial was to investigate the effects of feeding grains that are naturally contaminated with more realistic levels of DON on sows during late gestation and lactation.MethodsIn a commercial, high-yield specific pathogen-free piglet production unit, 45 Norwegian Landrace × Yorkshire sows were fed three diets from 93 ± 1 days of gestation until weaning of the piglets, and average daily feed intake (ADFI), body weight (BW), production and reproduction performance, as well as sow blood parameters were recorded. Diets were made from naturally contaminated oats, with three concentration levels: 1) control (DON < 0.2 mg/kg), 2) DON level 1 (1.4 mg DON/kg), and 3) DON level 2 (1.7 mg DON/kg).ResultsSows that were fed DON level 1 and 2 diets showed a 4–10% reduction in feed consumption during lactation, compared with sows in the control group. However, the DON-contaminated diets did not significantly affect sow BW or backfat thickness. Similarly, there were neither effects on production or reproduction performance, nor on blood parameters in the sows. The effects on skin temperature were variable.ConclusionNaturally contaminated diets with realistic, moderately increased DON levels, fed during late gestation and lactation in a modern high-yield piglet production farm, had limited effects on sow health and production.

Determination and Visualization of Different Levels of Deoxynivalenol in Bulk Wheat Kernels by Hyperspectral Imaging

A hyperspectral imaging system is proposed as a method to rapidly and nondestructively predict mycotoxin deoxynivalenol (DON) levels in FHB-infected wheat kernels. Standard normal variate transformation and multiplicative scatter correction (MSC) were used in spectral preprocessing. The successive projections algorithm (SPA) and random frog algorithm were used to select the optical wavelengths. Finally, the support vector machine (SVM) technique and partial least squares discriminant analysis were applied to establish different models for determining DON levels. Based on a comparison of the results, the MSC–SPA–SVM model, with the highest classification accuracy (100.00% for the training test and 97.92% for the testing set), gave the best performance, and a visualization map of the DON content level based on this model was created.

Influence of plant density on toxigenic fungal and mycotoxin contamination of maize grains

Field trials were set up in the Belgrade area (Serbia) in 2013 and 2014 to determine the effect of plant density on the natural incidence of potentially toxigenic fungi and the level of mycotoxins, aflatoxin B1 (AFB1), deoxynivalenol (DON) and fumonisins (FBs) in two Serbian maize hybrids of the FAO maturity group 700 (ZP 735 and NS Zenit). Three plant density treatments, namely, 55,000 plants ha−1 (PD1), 64,000 plants ha−1 (PD2) and 75,000 plants ha−1 (PD3), were evaluated.The incidence of identified potentially toxigenic fungi of the genera Aspergillus, Fusarium, and Penicillium and the FB level increased significantly (P ≤ 0.01) at PD3. The effect of year was also significant (P ≤ 0.01) on the incidence of toxigenic fungi, as all fungal species had a higher incidence in 2014 than in 2013, with the exception of Aspergillus spp. that showed a significantly higher incidence in 2013. Levels of all tested mycotoxins were higher in 2014 than in 2013. The higher incidence of Fusarium graminearum, Fusarium proliferatum, Fusarium subglutinans, Fusarium verticillioides and Penicillium spp. and higher levels of AFB1 and FBs were observed in the hybrid ZP 735, whereas the hybrid NS Zenit had a higher incidence of Aspergillus spp. The effect of hybrids was not significant on the incidence of F. subglutinans and the DON level.These results indicated that the highest investigated plant density increased the fungal incidence and the FB level, especially in 2014. Although the two hybrids originated from the same FAO group, they differed in their effects on some toxigenic fungi and mycotoxins.

Deoxynivalenol decreased intestinal immune function related to NF-κB and TOR signalling in juvenile grass carp (Ctenopharyngodon idella)

Deoxynivalenol (DON) is one of the most common mycotoxins in animal feed worldwide and causes significant threats to the animal production. The intestine is an important mucosal immune organ in teleost, and it is also the first target for feed-borne toxicants in animal. However, studies concerning the effect of DON on fish intestine are scarce. This study explored the effects of DON on intestinal immune function in juvenile grass carp (Ctenopharyngodon idella). A total of 1440 juvenile grass carp (12.17 ± 0.01 g) were fed six diets containing graded levels of DON (27, 318, 636, 922, 1243 and 1515 μg/kg diet) for 60 days. After the growth trial, fish were challenged with Aeromonas hydrophila. The results were analysed by the Duncan's multiple-range test (P < 0.05), indicating that compared with the control group (27 μg/kg diet), dietary DON levels up to 318 μg/kg diet: (1) decreased lysozyme (LZ) and acid phosphatase (ACP) activities, as well as complement 3 (C3), C4 and immunoglobulin M (IgM) content in the proximal intestine (PI), middle intestine (MI) and distal intestine (DI) of juvenile grass carp (P < 0.05); (2) down-regulated the mRNA levels of anti-microbial substance: liver expressed antimicrobial peptide (LEAP) -2A, LEAP-2B, hepcidin, β-defensin-1 and mucin2 in the PI, MI and DI of juvenile grass carp (P < 0.05); (3) up-regulated the mRNA levels of pro-inflammatory cytokines [interleukin 1β (IL-1β), tumour necrosis factor α (TNF-α), interferon γ2 (INF-γ2), IL-6 (only in PI), IL-8, IL-12p35, IL-12p40, IL-15 and IL-17D] in the PI, MI and DI of juvenile grass carp (P < 0.05), which might be partly related to nuclear factor kappa B (NF-κB) signalling [IκB kinase β (IKKβ) and IKKγ/inhibitor of κBα (IκBα)/NF-κB (p65 and c-Rel)]; and (4) down-regulated the mRNA levels of anti-inflammatory cytokines [IL-10, IL-11, IL-4/13A (not IL-4/13B), transforming growth factor β1 (TGF-β1) (not TGF-β2)] in the PI, MI and DI of juvenile grass carp (P < 0.05), which might be partly related to target of rapamycin (TOR) signalling [TOR/ribosomal protein S6 kinases 1 (S6K1) and eIF4E-binding proteins (4E-BP)]. All data indicated that DON could impair the intestinal immune function, and its potential regulation mechanisms were partly associated with NF-κB and TOR signalling pathways. Finally, based on the enteritis morbidity, and the LZ and ACP activities as well as IgM content in the PI, the reasonable dose of DON for grass carp were estimated to be 251.66, 305.83, 252.34 and 309.94 μg/kg diet, respectively.

Vliv fungicidního ošetření a podmínek skladování na hladiny vybraných mykotoxinů u ječmene

The aim of the study was to determine the effect of fungicidal treatment and storage on the occurrence of mycotoxins in barley (Hordeum vulgare L.). Barley was initially inoculated with Fusarium culmorum followed by the application of fungicides (prothioconazole and bixafen). A screening of 57 mycotoxins were performed using ultra-performance liquid chromatography in tandem with mass spectrometry. The fungicide treatment affected (P <0.05) the levels of zearalenone, β-zearalenol, arternariol and alternariol-methylether that were present. Levels of deoxynivalenol was highest in the second year of monitoring. 3-acetyl-deoxynivalenol was not affected by fungicidal treatment or storage. The significant increase (P <0.05) of DON-3-glucoside, 15-acetyl-DON, enniatin A, enniatin A1, enniatin B, and enniatin B1 was measured in barley samples. The results of the experiment determined that the use of fungicides can suppress some kinds of mycotoxins, but not others.

Effect of Wheat Cultivar on the Concentration of Fusarium Mycotoxins in Wheat Stems

Effective control of Fusarium-mycotoxin accumulation in grain affected by Fusarium head blight (FHB) (caused by Fusarium graminearum) begins with selecting moderately resistant wheat cultivars; however, little is known about how this resistance affects mycotoxin levels in the stem. A study was conducted from 2011 to 2014 in a mist-irrigated FHB nursery in Urbana, IL to determine whether the FHB resistance class of a cultivar (very susceptible, susceptible, moderately susceptible, and moderately resistant) affects the concentration of Fusarium mycotoxins in the stem. FHB incidence, FHB severity, and Fusarium-damaged kernel ratings were collected and used to calculate FHB index; incidence, severity, and kernel damage (ISK) index; and deoxynivalenol (DON), incidence, severity, and kernel damage (DISK) index. Grain was assayed for levels of DON, and the bottom 25 cm of plant stems was collected from each plot and assayed for DON, 3-acetyl-deoxynivalenol (3ADON), and 15-acetyl-deoxynivalenol (15ADON). Significant differences in DON concentration in the grain were detected among cultivars (P = 0.0001) and for the concentration of all DON (P = 0.003), 3ADON (P = 0.03), and 15ADON (P < 0.0001) in the stem. Significant differences among resistance classes were observed for FHB index value (P < 0.0001), ISK index (P = 0.006), and DISK index (P = 0.004). In all years of this study, the concentration of DON in the grain and the concentrations of all mycotoxins in the stem were consistently lower in the moderately resistant cultivars. All three indices were poor indicators of mycotoxin concentrations in the stem. Overall, the selection of a moderately resistant cultivar provides effective control of DON accumulation in the grain and mycotoxin accumulation in the stem.

Co-occurrence of mycotoxins in maize food and maize-based feed from small-scale farms in Brazil: a pilot study.

A limited survey was conducted to assess the co-occurrence of aflatoxins (AF) B1, B2, G1, and G2; fumonisins (FB) B1 and B2; ochratoxin A (OTA); zearalenone (ZEN); and deoxynivalenol (DON) in maize food (N = 26) and animal feed (N = 45) collected from 21 small-scale farms from the states of São Paulo (SP) and Santa Catarina (SC), Brazil. Samples evaluated were maize meal and maize flour for human consumption available in the farm households, and maize-based feed intended for broiler chicks, laying hens, and dairy cows. Analyses of mycotoxins were performed by ultra-performance liquid chromatography coupled with tandem mass spectrometry. The median levels of mycotoxins found in maize food were 2.5μg/kg (total AF), 120μg/kg (total FB), 13μg/kg (ZEN), and 57μg/kg (DON). All values were below the Brazilian tolerance limits, except for total FB in one sample of maize flour. In feed samples, median levels of total AF, total FB, ZEN, and DON were 100μg/kg, 680μg/kg, 160μg/kg, and 200μg/kg, respectively. The co-occurrence of two or more mycotoxins was confirmed in 35% and 51% of maize food and feed, respectively. Results indicate a low human exposure to mycotoxins in the small-scale farms evaluated and a higher exposure of farm animals to mycotoxins in the feed.

Malting of Fusarium Head Blight-Infected Rye (Secale cereale): Growth of Fusarium graminearum, Trichothecene Production, and the Impact on Malt Quality.

This project was initiated with the goal of investigating the malt quality of winter rye cultivars and hybrids grown in the United States in 2014 and 2015, but high levels of deoxynivalenol (DON) were subsequently found in many of the malt samples. DON levels in 75% of the investigated rye samples (n = 117) were actually below 1.0 mg/kg, as quantified by a gas chromatography combined with electron capture detector (GC-ECD). However, 83% of the samples had DON in excess of 1.0 mg/kg following malting, and the average DON level in malted rye was 10.6 mg/kg. In addition, relatively high levels of 3-acetate DON (3-ADON), 15-acetate DON (15-ADON), nivalenol (NIV), and DON-3-glucoside (D3G) were observed in some rye malts. Our results show that rye grain DON is likely a poor predicator of type B trichothecenes in malt in practice, because high levels of malt DON, 15-ADONm and D3G were produced, even when the rye samples with DON levels below 0.50 mg/kg were processed. Fusarium Tri5 DNA content in rye was highly associated with malt DON levels (r = 0.83) in a small subset of samples (n = 55). The impact of Fusarium infection on malt quality was demonstrated by the significant correlations between malt DON levels and wort viscosity, β-glucan content, wort color, wort p-coumaric acid content, and total phenolic content. Additional correlations of rye Fusarium Tri5 DNA contents with malt diastatic power (DP), wort free amino nitrogen (FAN) content, and arabinoxylan content were observed.