Mycotoxins and coccidiosis in poultry - co-occurrence, interaction, and effects.

Avian coccidiosis, a common disease caused by Eimeria species, results in significant losses in global poultry production. Mycotoxins are low-molecular-weight natural products (i.e., small molecules) produced as secondary metabolites by filamentous fungi and they have the potential to economically and significantly affect global poultry production. Little is known about the relationship between mycotoxins and avian coccidiosis, although they often co-occur in the field. This comprehensive review examines the intricate relationship between mycotoxins and avian coccidiosis, in particular how mycotoxins, including aflatoxins, ochratoxins, trichothecenes as well as Fusarium mycotoxins, compromise the health of the poultry flock and open the door to Eimeria parasites in the gut. In addition, this review sheds light on the immunosuppressive effects of mycotoxins, their disruption of cellular signaling pathways, and the consequent exacerbation of coccidiosis infections. The mechanisms of mycotoxin toxicity are also reviewed, emphasizing direct damage to intestinal epithelial cells, impaired nutrient absorption, inflammation, oxidative stress, and changes in the gut microbiota. Finally, the consequences for the prevention and treatment of coccidiosis when mycotoxins are present in the feed are discussed. This review emphasizes the need for effective management strategies to mitigate the combined risks of mycotoxins and coccidiosis and highlights the complexity of diagnosing and controlling these interrelated problems in poultry. The review advocates a holistic approach that includes strict feed management, disease prevention measures and regular monitoring to maintain the health and productivity of poultry against these significant challenges.

Low Molecular Weight and High Deacetylation Degree Chitosan Batch Alleviates Pathogenesis, Toxin Accumulation, and Fusarium Gene Regulation in Barley Leaf Pathosystem.

Fusarium graminearum is a cosmopolitan fungal pathogen that destroys cereal production, in terms of loss of yield and grain contamination with mycotoxins, worldwide. Chitosan is a natural biopolymer abundant in the environment with proven antifungal properties that also acts as a plant immunity elicitor. Despite a number of articles, there is a lack of systematic comparison of antifungal activity of diverse batches of chitosan. The current study aimed to test the inhibitory effects of a collection of diverse chitosan samples on the growth and production of F. graminearum toxins, validated by changes in the Fusarium transcriptome. Experiments included testing antifungal activity of different chitosan samples, the application of the best performing one in vitro to investigate the impact on F. graminearum growth, followed by analyzing its effect on Fusarium toxins accumulation, and Fusarium transcriptomics in the barley leaf pathosystem. Confirmatory antifungal assays revealed that CS_10, a specific batch of chitosan, retarded Fusarium growth with an application concentration of 200 ppm, significantly reducing toxin synthesis and disease symptoms in Fusarium-inoculated barley leaves. RNA-Seq analysis of F. graminearum in barley leaf pathosystem exposed to CS_10 showed a list of differentially expressed genes involved in redox balance, cell respiration, nutrient transport, cell wall degradation enzymes, ergosterol biosynthesis, and trichothecenes production. The genes functioning in these essential pathways are discussed and assigned as critical checkpoints to control Fusarium infections. The results suggest some important molecular targets in F. graminearum that may be suitable in gene-specific targeting or transgene-free methods, such as spray-induced gene silencing during host-pathogen interactions.

Occurrence of Fusarium mycotoxins in freshly harvested highland barley (qingke) grains from Tibet, China.

Highland barley, also called "qingke" in Tibetan, is mainly cultivated in the Tibetan Plateau of China and has been used as a major staple food for Tibetans. Recently, Fusarium head blight (FHB) of qingke was frequently observed around the Brahmaputra River in Tibet. Considering the importance of qingke for Tibetans, the assessment of Fusarium mycotoxin contamination is essential for food safety. In this study, a total of 150 freshly harvested qingke grain samples were obtained from three regions around the Brahmaputra River in Tibet (China) in 2020. The samples were investigated for the occurrence of 20 Fusarium mycotoxins using high-performance liquid chromatography-tandem mass spectrometry (HPLC‒MS/MS). The most frequently occurring mycotoxin was enniatin B (ENB) (46%), followed by enniatin B1 (ENB1) (14.7%), zearalenone (ZEN) (6.0%), enniatin A1 (ENA1) (3.3%), enniatin A (ENA) (1.3%), beauvericin (BEA) (0.7%), and nivalenol (NIV) (0.7%). Due to the increase in altitude, the cumulative precipitation level and average temperature decreased from the downstream to the upstream of the Brahmaputra River; this directly correlated to the contamination level of ENB in qingke, which gradually decreased from downstream to upstream. In addition, the level of ENB in qingke obtained from qingke-rape rotation was significantly lower than that from qingke-wheat and qingke-qingke rotations (p < 0.05). These results disseminated the occurrence of Fusarium mycotoxins and provided further understanding of the effect of environmental factors and crop rotation on Fusarium mycotoxins.

Free and Modified Mycotoxins in Organic and Conventional Oats (Avena sativa L.) Grown in Scotland.

Small grain cereals are frequently infected with mycotoxigenic Fusarium fungi. Oats have a particularly high risk of contamination with type A trichothecene mycotoxins; their glucoside conjugates have also been reported. Agronomy practices, cereal variety and weather conditions have been suggested to play a role in Fusarium infection in oats. The current study investigates concentrations of free and conjugated Fusarium mycotoxins in organic and conventional oats grown in Scotland. In 2019, 33 milling oat samples (12 organic, 21 conventional) were collected from farmers across Scotland, together with sample questionnaires. Samples were analysed for 12 mycotoxins (type A trichothecenes T-2-toxin, HT-2-toxin, diacetoxyscirpenol; type B trichothecenes deoxynivalenol, nivalenol; zearalenone and their respective glucosides) using LC-MS/MS. The prevalence of type A trichothecenes T-2/HT-2 was very high (100% of conventional oats, 83% of organic oats), whereas type B trichothecenes were less prevalent, and zearalenone was rarely found. T-2-glucoside and deoxynivalenol-glucoside were the most prevalent conjugated mycotoxins (36 and 33%), and co-occurrence between type A and B trichothecenes were frequently observed (66% of samples). Organic oats were contaminated at significantly lower average concentrations than conventional oats, whereas the effect of weather parameters were not statistically significant. Our results clearly indicate that free and conjugated T-2- and HT-2-toxins pose a major risk to Scottish oat production and that organic production and crop rotation offer potential mitigation strategies.

A Study of a New Certified Reference Material for Accurate Determination of the Main Fusarium Mycotoxins in Whole-Wheat Flour.

Matrix certified reference materials (CRMs) play a critical role in analytical method validation and the assurance of reliable measurement results. A certified reference material (GBW(E)100813) for whole-wheat flour was developed to ensure an accurate and reliable measurement of the main Fusarium mycotoxins (deoxynivalenol (DON), nivalenol (NIV), deoxynivalenol-3-glucoside (DON-3G), and zearalenone (ZEN)). CRM candidates were prepared using sun-drying, grinding, sieving, homogenising, packaging, and gamma irradiation. The final produced CRM was packaged at 50 g per unit and stored at 20 °C. Certification was performed using isotope dilution-liquid chromatography-tandem mass spectrometry. CRM characterization was performed in eight laboratories in accordance with the requirements of ISO Guide 35. The certified values and expanded uncertainties (at a confidence of 95%, k = 2) for DON, NIV, DON-3G, and ZEN were determined to be 0.98 ± 0.12 mg/kg, 1.37 ± 0.20 mg/kg, 242 ± 35 µg/g, and 382 ± 50 µg/g. The CRM was sufficiently homogeneous between and within bottles, and remained stable for up to 12 months at 20 °C and 9 days below 40 °C for transportation. Thus, CRM can be used for quality control and method validation to ensure the accurate and reliable quantification of the main Fusarium mycotoxins in whole-wheat flour.

Impact of a Natural Fusarial Multi-Mycotoxin Challenge on Broiler Chickens and Mitigation Properties Provided by a Yeast Cell Wall Extract and a Postbiotic Yeast Cell Wall-Based Blend.

Yeast cell wall-based preparations have shown efficacy against Aspergillus-based toxins but have lower impact against type-B trichothecenes. Presently, we investigated a combination of deoxynivalenol (DON), T-2 toxin (T2) and zearalenone (ZEA), and the effect of a yeast cell wall extract (YCWE) and a post-biotic yeast cell wall-based blend (PYCW) with the objectives of preventing mycotoxins' negative effects in commercial broilers. A total of 720 one-day-old male Cobb broilers were randomly allocated to: (1) control diet, (aflatoxins 6 µg/kg; cyclopiazonic acid 15 µg/kg; fusaric acid 25 µg/kg; fumonisin B1 310 µg/kg); (2) Diet1 + 0.2% YCWE; (3) Diet1 + 0.2% PYCW; (4) Contaminated diet (3.0 mg/kg DON; 2.17 mg/kg 3-acetyldeoxynivalenol; 104 g/kg T2; 79 g/kg ZEA); (5) Diet4 + 0.2% YCWE; and (6) Diet4 + 0.2% PYCW. Naturally contaminated diets adversely affected performance, serum biochemistry, liver function, immune response, altered cecal SCFA goblet cell count and architecture of intestinal villi. These adverse effects were reduced in birds fed PYCW and to a lesser extent YCWE, indicating protection against toxic assault. PYCW yielded better production performance and stimulated liver function, with higher response to NDV and IBV vaccination. Furthermore, mycotoxins were found to affect production outputs when evaluated with the European poultry production efficiency factor compared to control or YCWE and PYCW supplemented treatments. Taken together, YCWE, when complemented with nutritional add-ons (PYCW), could potentiate the remediation of the negative effects from a multi mycotoxins dietary challenge in broiler birds.

Reduction of deoxynivalenol, T-2 and HT-2 toxins and associated Fusarium species during commercial and laboratory de-hulling of milling oats.

Oats (Avena sativa L.) are well known for their nutritional properties but are susceptible to the growth of different Fusarium fungi resulting in mycotoxin contamination of harvested oats. In this study, oat samples from harvest years 2011 to 2017 were preselected for their suitability as milling oats for food purposes with DON contents below 1750 µg/kg. The reduction of DON, T-2 and HT-2 toxins during the commercial de-hulling process was analysed. While the average reduction for the sum of T-2 and HT-2 toxins in large oat kernels was 85%, the reduction for thin kernels was 66%. The reduction for DON was about 60% and did not differ for the two kernel fractions. In laboratory de-hulling experiments, milling oat samples and de-hulled oat kernels with known DON, T-2 and HT-2 toxin content were correlated with the associated DNA amount of Fusarium graminearum, Fusarium culmorum and Fusarium langsethiae. The reduction of the Fusarium DNA amount after de-hulling was comparable to the reduction of the associated mycotoxins. Notably, the correlation between F. langsethiae DNA amounts and the sum of T-2 and HT-2 toxin contents was R2 = 0.69 in milling oats and it rose to R2 = 0.85 in de-hulled oat kernels. In laboratory tests, at least one third of the initial levels of DON and the sum of T-2 and HT-2 toxins could be removed by polishing off the first parts of the outer layers; two thirds remained in the polished oat kernels. These observations indicate that de-hulling alone may not be completely sufficient to remove mycotoxin contamination in oats. These findings are of high importance in the discussion of determining legal maximum levels for DON or the sum of T-2 and HT-2 toxins in intermediate and final products.

Emerging mycotoxins and reproductive effects in animals: A short review.

Emerging Fusarium mycotoxins beauvericin (BEA), enniatins (ENNs), and moniliformin (MON) are gaining increasing interest due to their wide presence especially in cereals and grain-based products. In vitro and in vivo studies indicate that Fusarium mycotoxins can be implicated in reproductive disorders in animals. Of these mycotoxins, BEA may affect reproductive functions, impairing the development of oocytes in pigs and sheep. Studies show dramatic inhibitory effects of BEA and ENNA on bovine granulosa cell steroidogenesis. ENNs also inhibit boar sperm motility and cause detrimental effects on embryos in mice and pigs. Although little data are reported on reproductive effects of MON, in vitro studies show inhibitory effects of MON on Chinese hamster ovary cells. The present review aims to summarize the reproductive toxicological effects of emerging Fusarium mycotoxins BEA, ENNs, and MON on embryo development, ovarian function, and testicular function of animals. In vitro and in vivo toxicological data are reported although additional studies are needed for proper risk assessment.

Comprehensive analysis of multiple mycotoxins and Aspergillus flavus metabolites in maize from Kenyan households.

This study assessed the levels of mycotoxins in maize from Kenyan households. Further, local open pollinated maize varieties were compared with commercial hybrids to evaluate which variety is less susceptible to mycotoxin contamination. Four hundred and eighty (n = 480) maize samples were collected in the years 2018-2020 from households in Eastern, Western, Coastal and Lake Victoria regions of Kenya. Liquid chromatography coupled to tandem mass spectrometry was used to detect and quantify 22 mycotoxins, along with 31 Aspergillus flavus metabolites in the samples. Eastern Kenya had the highest aflatoxin (AF) contamination with 75% of samples having AF levels above the Kenyan regulatory limits (10 µg/kg), the highest concentration was 558.1 µg/kg. In Western Kenya, only 18% of samples had concentration levels above the Kenyan regulatory limits for AF with highest sample having 73.3 µg/kg. The Lake Victoria region had the most fumonisins (F) contamination, with 53% of the samples having fumonisin B1 (FB1) < 1000 µg/kg. However, only 20% of the samples surpassed the Kenyan regulatory limit for total fumonisins (2000 µg/kg) with the highest concentration being 13,022 µg/kg. In addition, 21.6% of samples from the Lake Victoria region had zearalenone (ZEN) and deoxynivalenol (DON) above regulatory limits for European countries (1000 µg/kg). Western region had the least A. flavus metabolites contamination (18%) while the Eastern region had the highest incidence of A. flavus metabolites (81%). Among the A. flavus metabolites, cyclopiazonic acid (CPA), beta-cyclopiazonic acid (ß CPA), flavacol (FLV) and methylcitreo-isocoumarin (MIC) positively correlated with each other but negatively correlated with the other metabolites. Significant positive co-occurrence was also noted among Fusarium mycotoxins: nivalenol (NIV) positively correlated with DON (r = 0.81), fusarenon-X (FX) (r = 0.81) and ZEN (r = 0.70). Negative correlations were observed between Aspergillus and Fusarium mycotoxins: aflatoxin B1 (AFB1) negatively correlated with FB1 (r = -0.11), FX (r = -0.17) and ZEN (r = -0.20). Local open-pollinated maize varieties (L-opv) were less susceptible to mycotoxin contamination compared to the commercial hybrids (C-hy). This study reveals that Kenyan maize is contaminated with multiple mycotoxins most of which are not regulated in Kenya despite being regulated in other parts of the world. A comprehensive legislation should therefore be put in place to protect the Kenyan public against chronic exposure to these mycotoxins. In addition to high yield, there is a need for commercial hybrid maize breeders to incorporate mycotoxin resistance as an important trait in germplasm improvement in seeds production.

Occurrence and Dietary Exposure Assessment to Enniatin B through Consumption of Cereal-Based Products in Spain and the Catalonia Region.

Enniatin B (ENNB) is a mycotoxin produced by moulds from the Fusarium genera and its toxic effects are still not fully elucidated, hence a safe reference exposure value has not been established yet. ENNB is the most prevalent emerging mycotoxin and is widely found in cereal-based products, nevertheless, there are no comprehensive exposure assessment studies. For that reason, the aim of this study was to characterise the occurrence of ENNB and estimate the exposure of the Spanish and Catalan populations. A total of 347 cereal-based products were collected in 2019 and were analysed using liquid chromatography-tandem mass spectrometry. Consumption data were obtained from the national food consumption surveys (ENALIA) and a regional survey conducted in Catalonia. The global exposure was estimated using deterministic and probabilistic methods. The results showed a high occurrence of close to 100% in all foodstuffs, with a range from 6 to 269 µg/kg, and a strong correlation with the levels of deoxynivalenol. Children aged one-nine years were the most exposed, showing mean estimates in the range 308-324 ng/kg bw/day and 95th percentiles 697-781 ng/kg bw/day. This study stresses the need for further toxicological data to establish reference doses and conclude formal risk assessment, accounting for the co-occurrence with deoxynivalenol.

The Influence of Fusarium Mycotoxins on the Liver of Gilts and Their Suckling Piglets.

Mycotoxins are common fungal secondary metabolites in both animal feed and human food, representing widespread toxic contaminants that cause various adverse effects. Co-contamination with different mycotoxins is frequent; therefore, this study focused on feed contaminated with Fusarium mycotoxins, namely, deoxynivalenol (5.08 mg/kg), zearalenone (0.09 mg/kg), and fusaric acid (21.6 mg/kg). Their effects on the liver of gilts and their piglets were chosen as the research subject as pigs are one of the most sensitive animal species that are also physiologically very similar to humans. The gilts were fed the experimental diet for 54 ± 1 day, starting late in their pregnancy and continuing until roughly a week after weaning of their piglets. Livers of gilts and their piglets were assessed for different histopathological changes, apoptosis, and proliferation activity of hepatocytes. On histopathology, gilts fed the experimental diet had a statistically significant increase in hepatocellular necrosis and apoptosis (p = 0.0318) as well as sinusoidal leukocytosis with inflammatory infiltrates of hepatic lobules (p = 0.0004). The amount of interlobular connective tissue in the liver of experimental gilts was also significantly decreased (p = 0.0232), implying a disruption in the formation of fibrous connective tissue. Apoptosis of hepatocytes and of cells in hepatic sinusoids, further assessed by the terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, showed a statistically significant increase (p = 0.0224 and p = 0.0007, respectively). No differences were observed in piglet livers. These results indicated that Fusarium mycotoxins elicited increased apoptosis, necrosis, and inflammation in the liver of gilts, but caused no effects on the liver of piglets at these concentrations.

Effect of Selected Cooking Ingredients for Nixtamalization on the Reduction of Fusarium Mycotoxins in Maize and Sorghum.

Although previous studies have reported the use of nixtamalization for mycotoxins reduction in maize, the efficacy of calcium hydroxide and other nixtamalization cooking ingredients for mycotoxin reduction/decontamination in sorghum and other cereals still need to be determined. The current study investigated the effect of five nixtamalization cooking ingredients (wood ashes, calcium hydroxide, sodium hydroxide, potassium hydroxide, and calcium chloride) on the reduction of Fusarium mycotoxins in artificially contaminated maize and sorghum using liquid chromatography-tandem mass spectrometry. All tested cooking ingredients effectively reduced levels of mycotoxins in the contaminated samples with reduction initiated immediately after the washing step. Except for the calcium chloride nixtamal, levels of fumonisin B1, B2, and B3 in the processed sorghum nixtamal samples were below the limit of detection. Meanwhile, the lowest pH values were obtained from the maize (4.84; 4.99), as well as sorghum (4.83; 4.81) nejayote and nixtamal samples obtained via calcium chloride treatment. Overall, the results revealed that the tested cooking ingredients were effective in reducing the target mycotoxins. In addition, it pointed out the potential of calcium chloride, though with reduced effectiveness, as a possible greener alternative cooking ingredient (ecological nixtamalization) when there are environmental concerns caused by alkaline nejayote.

A Two-Year Occurrence of Fusarium T-2 and HT-2 Toxin in Croatian Cereals Relative of the Regional Weather.

To investigate into the T-2 and HT-2 toxin occurrence, 240 samples of unprocessed cereals (maize, wheat, barley, and oats) were sampled from different fields located in three Croatian regions during 2017-2018. In all samples, sum concentrations of T-2/HT-2 toxin were determined using the ELISA method, while the LC-MS/MS was used as a confirmatory method for both mycotoxins in positive samples (>LOD) and the establishment of T-2 over HT-2 toxin ratios. The results showed oats to be the most contaminated cereal, with T-2/HT-2 toxins detected in 70.0% of samples, followed by barley (40.9%), maize (26.8%) and wheat (19.2%), with the mean T-2/HT-2 ratio ranging from 1:2.7 in maize to 1:4.4 in oats. Sum T-2/HT-2 concentrations in two maize samples were higher than the indicative level recommended by the European Commission, necessitating subsequent investigations into the conditions under which these poorly investigated mycotoxins are produced. Statistically significantly (p < 0.05) higher concentrations of T-2/HT-2 toxin were determined in oats throughout study regions as compared to those found in wheat, but not maize and barley, while the concentrations of these mycotoxins were related to the regional weather in Croatia.

Beauvericin and Enniatins: In Vitro Intestinal Effects.

Food and feed contamination by emerging mycotoxins beauvericin and enniatins is a worldwide health problem and a matter of great concern nowadays, and data on their toxicological behavior are still scarce. As ingestion is the major route of exposure to mycotoxins in food and feed, the gastrointestinal tract represents the first barrier encountered by these natural contaminants and the first structure that could be affected by their potential detrimental effects. In order to perform a complete and reliable toxicological evaluation, this fundamental site cannot be disregarded. Several in vitro intestinal models able to recreate the different traits of the intestinal environment have been applied to investigate the various aspects related to the intestinal toxicity of emerging mycotoxins. This review aims to depict an overall and comprehensive representation of the in vitro intestinal effects of beauvericin and enniatins in humans from a species-specific perspective. Moreover, information on the occurrence in food and feed and notions on the regulatory aspects will be provided.

The effects of feed naturally contaminated with Fusarium mycotoxins on the thymus in suckling piglets.

In this study, feed naturally containing Fusarium mycotoxins was fed to gilts during the perinatal period, and the effects on the thymus were investigated in one-week-old piglets. Twenty gilts were divided into equal control (0.26 mg deoxynivalenol, DON) and experimental (5.08 mg DON, 0.09 mg zearalenone and 21.61 mg fusaric acid per kg of feed) groups. One suckling piglet from each litter (n = 20) was sacrificed at one week of age to obtain thymus samples for further analysis. The cortex to medulla ratio of the thymus was morphometrically analysed using NIS Elements BR (Nikon) software. Paraffin-embedded thymus sections were stained to quantify apoptosis (with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling - TUNEL method), cellular proliferation (Ki-67) and macrophages (MAC 387). The results showed that the thymus cortex (P = 0.023) to medulla (P = 0.023) ratio was significantly lower in the experimental group. The number of apoptotic cells (cortex, P = 0.010, medulla, P = 0.001) and the number of proliferating cells in the thymus cortex (P = 0.001) and medulla (P < 0.001) were significantly higher in the experimental group. Our results indicate that feeding Fusarium mycotoxins to a parent animal during the perinatal period induces significant alterations in the thymus of one-week-old piglets, which indicates an immunosuppressive effect in piglets.

Occurrence of Mycotoxins in Winter Rye Varieties Cultivated in Poland (2017-2019).

Rye (Secale cereale L.) is one of the most important cereals and is used in both the food and feed industries. It is produced mainly in a belt extending from Russia through Poland to Germany. Despite the great economic importance of this cereal, there is little research on rye contamination with mycotoxins. In this study, the occurrence of Fusarium mycotoxins (deoxynivalenol, nivalenol, 3-acetyl-deoxynivalenol, monoacetoxyscirpenol, diacetoxyscirpenol, T-2 toxin, HT-2 toxin, and zearalenone), as well as ochratoxin A, in 60 winter rye samples of four varieties (KWS Binntto, KWS Serafino, Dankowskie Granat and Farm Saved Seed) cultivated in three consecutive growing seasons in five different regions of Poland was determined using liquid chromatography with tandem mass spectrometry and fluorescence detection. Deoxynivalenol, T-2 toxin, HT-2 toxin, and zearalenone had the highest occurrence in samples (90%, 63%, 57%, and 45% positive results, respectively). The mean concentrations of these analytes were 28.8 µg/kg (maximum 354.1 µg/kg), 0.98 µg/kg (maximum 6.63 µg/kg), 2.98 µg/kg (maximum 29.8 µg/kg), and 0.69 µg/kg (maximum 10.2 µg/kg), respectively. The mean concentrations for individual mycotoxins were highest in the 2016/2017 growing season. In the 2016/2017 growing season, at least two mycotoxins were detected in 95% of the samples, while in the 2018/2019 growing season, 70% of samples contained one or no mycotoxins. The frequencies of mycotoxin occurrence in different rye varieties were similar. Although a high frequency of mycotoxin occurrence was noted (especially deoxynivalenol), their concentrations were low, and none of the analyzed rye samples exceeded the maximum acceptable mycotoxin level set by the European Commission.

Tri-octahedral bentonites as potential technological feed additive for Fusarium mycotoxin reduction.

In 2009 the EU Regulation 386/2009 established a new functional group of feed additives called "substances for reduction of the contamination of feed by mycotoxin". Later, di-octahedral bentonite (1 m558) was authorised, as an anti-aflatoxin additive, being the only additive of this group authorised to date. This work aims to demonstrate the effectiveness of other bentonites, such as tri-octahedral bentonites, versus Fusarium-mycotoxins, since very few adsorbents have proved their effectiveness in relation to this group of mycotoxins. For this purpose, 7 bentonites (six of them tri-octahedral) and 7 commercial adsorbents, added at 0.02% (w/v), were assayed in an in vitro adsorption experiment using two simulated gastro-intestinal (GI) juices (pH 1.3 and 6.8) versus zearalenone (ZEN: 0.1-5 mg/L), fumonisin B1 (FB1: 1-10 mg/L) and deoxynivalenol (DON: 2-10 mg/L). Mycotoxin adsorption data were fitted to Langmuir and Freundlich isotherms. In vitro adsorption experiments showed that ZEN and FB1 (in the latter case only in acid medium) were partially adsorbed, while the adsorption of DON was negligible. Moreover, the increase of adsorbent dose (up to 0.20%, w/v) significantly improved the in vitro adsorption of ZEN and FB1, reaching >90% of adsorption. The present work proposes the use of some tri-octahedral bentonites as feed additives for Fusarium-mycotoxin reduction.

Metabolomics-guided analysis reveals a two-step epimerization of deoxynivalenol catalyzed by the bacterial consortium IFSN-C1.

Deoxynivalenol (DON) is commonly found in wheat and wheat-derived foods, posing a threat to human health. Biodegradation is an efficient and eco-friendly measure for mycotoxin detoxification. Understanding the mechanism of DON biodegradation is hence of great importance. Herein, we report the application of metabolomics methods for the analysis of DON degradation by a bacterial consortium isolated from wheat leaves collected in Jiangsu Province. Metabolomics analysis combined with a nuclear magnetic resonance analysis revealed the main degradation product, 3-keto-DON, and a minor degradation product, 3-epi-DON. Further study illustrated that DON underwent a two-step epimerization through the intermediate 3-keto-DON. Sequencing analysis of the 16S rRNA metagenome of the microorganismal community suggested that the abundance of three bacterial genera, Achromobacter, Sphingopyxis, and Sphingomonas, substantially increased during the coculture of bacterial consortium and DON. Further investigation revealed that Devosia sp. might be responsible for the epimerization of 3-keto-DON. These findings shed light on the catabolic pathways of DON during biodegradation and illustrate the potential of using metabolomics approaches in biodegradation studies.Key Points• A bacterial consortium was isolated with good deoxynivalenol-degrading potential. • Metabolomics approaches were successfully used to interpret the degradation pathway. • A trace-amount degradation product was determined by metabolomics and NMR analysis. Graphical Abstract .

Co-Occurrence of Moniliformin and Regulated Fusarium Toxins in Maize and Wheat Grown in Italy.

The co-occurrence of moniliformin (MON), fumonisins (FBs), and deoxynivalenol (DON) was evaluated in maize, durum, and common wheat grown in different experimental fields located in several Italian regions. MON was quantified using a LC-MS/MS method adding lanthanum ions in the mobile phase. In maize, MON contamination was widespread and considerable; the toxin was detected in almost all the samples (95.1%) and exceeded 500 and 1000 µg kg-1 in 42.0% and in 18.5% of samples, respectively. Significant positive correlation was found between MON and FB contamination levels. When there were not droughty climate conditions, a positive significant correlation was found between growing degree days (GDD) and MON values. In wheat, MON contamination was not widespread like in maize and it was lower in common wheat than in durum wheat. In durum wheat, MON was detected in 45.0% of the samples with only 6 samples (7.5%) exceeding 500 µg kg-1, while in common wheat the toxin was detected above the LOD in 18.7% of samples exceeding 100 µg kg-1 in only two samples (2.5%). No correlation was found with DON contamination. Climate conditions influenced both MON and DON occurrence.

Fusarium mycotoxins in total mixed rations for dairy cows.

Mycotoxins produced by certain fungal species of the Fusarium genus are frequently found as contaminants in cereals and feedstuffs. Fumonisins (FBs), deoxynivalenol (DON) and zearalenone (ZEN) are of special concern relative to animal health and productivity. The aim of this work was to analyse the levels of Fusarium mycotoxin contamination in samples of total mixed rations (TMRs) for dairy cows. To accomplish this analysis, an HPLC-MS/MS multi-mycotoxin method was developed and validated. The relation between the formulation of TMR samples and the presence of mycotoxins was also studied. From February 2016 to January 2018, a total of 193 TMR samples for dairy cows collected from farms located in different areas of Spain were analysed for the presence of FBs, ZEN, DON and their metabolites. In total, 112 samples (58%) were contaminated with at least one mycotoxin, and 38 samples (20%) presented more than one mycotoxin. FBs were the mycotoxins most frequently found (34% positive samples). DON was detected in 17% of samples, and ZEN was detected in 16% of samples. Among the metabolites analysed, only deoxynivalenol-3-glucoside (DON-3-Glc) and 15-acetyldeoxynivalenol (15-ADON) were detected. The levels of all the Fusarium mycotoxins studied were always below the values recommended by the European Commission for feedstuffs. The wide variety of ingredients used in the formulation of the analysed samples made it difficult to reach definite conclusions, although it seemed that some cereal silages and concentrates such as cereals or compound feed used as ingredients of the TMR may be related to the presence of mycotoxins.