Occurrence of deoxynivalenol and deoxynivalenol-3-glucoside in hard red spring wheat grown in the USA

Integrating genomics, phenomics, and deep learning improves the predictive ability for Fusarium head blight-related traits in winter wheat

Fusarium head blight (FHB) remains one of the most destructive diseases of wheat (Triticum aestivum L.), causing considerable losses in yield and end-use quality. Phenotyping of FHB resistance traits, Fusarium-damaged kernels (FDK), and deoxynivalenol (DON), is either prone to human biases or resource expensive, hindering the progress in breeding for FHB-resistant cultivars. Though genomic selection (GS) can be an effective way to select these traits, inaccurate phenotyping remains a hurdle in exploiting this approach. Here, we used an artificial intelligence (AI)-based precise FDK estimation that exhibits high heritability and correlation with DON. Further, GS using AI-based FDK (FDK_QVIS/FDK_QNIR) showed a two-fold increase in predictive ability (PA) compared to GS for traditionally estimated FDK (FDK_V). Next, the AI-based FDK was evaluated along with other traits in multi-trait (MT) GS models to predict DON. The inclusion of FDK_QNIR and FDK_QVIS with days to heading as covariates improved the PA for DON by 58% over the baseline single-trait GS model. We next used hyperspectral imaging of FHB-infected wheat kernels as a novel avenue to improve the MT GS for DON. The PA for DON using selected wavebands derived from hyperspectral imaging in MT GS models surpassed the single-trait GS model by around 40%. Finally, we evaluated phenomic prediction for DON by integrating hyperspectral imaging with deep learning to directly predict DON in FHB-infected wheat kernels and observed an accuracy (R2 = 0.45) comparable to best-performing MT GS models. This study demonstrates the potential application of AI and vision-based platforms to improve PA for FHB-related traits using genomic and phenomic selection.

Influence of Biotreatment on Hordeum vulgare L. Cereal Wholemeal Contamination and Enzymatic Activities

Crop contamination with mycotoxins is a global problem with a negative impact on human and animal health as well as causing economical losses in food and feed chains. This study was focused on the evaluation of the effect of lactic acid bacteria (LAB) strain (Levilactobacillus brevis-LUHS173, Liquorilactobacillus uvarum-LUHS245, Lactiplantibacillus plantarum-LUHS135, Lacticaseibacillus paracasei-LUHS244 and Lacticaseibacillus casei-LUHS210) fermentation on the changes in the level of deoxynivalenol (DON) and its conjugates in Fusarium spp.-contaminated barley wholemeal (BWP). Samples, with different contamination of DON and its conjugates, were treated separately (for 48 h). In addition to mycotoxin content, enzymatic activities (amylolytic, xylanolytic, and proteolytic) of BWP (before and after fermentation) were evaluated. It was established that the effect of decontamination depends on the LAB strain used, and a significant reduction in DON and the concentration of its conjugates in Lc. casei fermented samples was achieved: the amount of DON decreased on average by 47%, and the amount of D3G, 15-ADON and 3-ADON decreased by 82.4, 46.1, and 55.0%, respectively. Lc. casei also showed viability in the contaminated fermentation medium and an effective production of organic acids was obtained. Additionally, it was found that enzymes are involved to the detoxification mechanism of DON and its conjugates in BWP. These findings indicate that fermentation with selected LAB strains could be applied for contaminated barley treatment in order to significantly reduce Fusarium spp. mycotoxin levels in BWP and improve the sustainability of grain production.

Modified Mycotoxins, a Still Unresolved Issue

Mycotoxins are toxic secondary metabolites produced by filamentous microfungi on almost every agricultural commodity worldwide. After the infection of crop plants, mycotoxins are modified by plant enzymes or other fungi and often conjugated to more polar substances, like sugars. The formed—often less toxic—metabolites are stored in the vacuole in soluble form or bound to macromolecules. As these substances are usually not detected during routine analysis and no maximum limits are in force, they are called modified mycotoxins. While, in most cases, modified mycotoxins have lower intrinsic toxicity, they might be reactivated during mammalian metabolism. In particular, the polar group might be cleaved off (e.g., by intestinal bacteria), releasing the native mycotoxin. This review aims to provide an overview of the critical issues related to modified mycotoxins. The main conclusion is that analytical aspects, toxicological evaluation, and exposure assessment merit more investigation.

Modified Fusarium Mycotoxins in Cereals and Their Products-Metabolism, Occurrence, and Toxicity: An Updated Review

Mycotoxins are secondary fungal metabolites, toxic to humans, animals and plants. Under the influence of various factors, mycotoxins may undergo modifications of their chemical structure. One of the methods of mycotoxin modification is a transformation occurring in plant cells or under the influence of fungal enzymes. This paper reviews the current knowledge on the natural occurrence of the most important trichothecenes and zearalenone in cereals/cereal products, their metabolism, and the potential toxicity of the metabolites. Only very limited data are available for the majority of the identified mycotoxins. Most studies concern biologically modified trichothecenes, mainly deoxynivalenol-3-glucoside, which is less toxic than its parent compound (deoxynivalenol). It is resistant to the digestion processes within the gastrointestinal tract and is not absorbed by the intestinal epithelium; however, it may be hydrolysed to free deoxynivalenol or deepoxy-deoxynivalenol by the intestinal microflora. Only one zearalenone derivative, zearalenone-14-glucoside, has been extensively studied. It appears to be more reactive than deoxynivalenol-3-glucoside. It may be readily hydrolysed to free zearalenone, and the carbonyl group in its molecule may be easily reduced to α/β-zearalenol and/or other unspecified metabolites. Other derivatives of deoxynivalenol and zearalenone are poorly characterised. Moreover, other derivatives such as glycosides of T-2 and HT-2 toxins have only recently been investigated; thus, the data related to their toxicological profile and occurrence are sporadic. The topics described in this study are crucial to ensure food and feed safety, which will be assisted by the provision of widespread access to such studies and obtained results.

Occurrence of deoxynivalenol and deoxynivalenol-3-glucoside in durum wheat from Argentina

The occurrence of deoxynivalenol, 3- and 15-deoxynivalenol and deoxynivalenol-3-glucoside in 84 durum wheat samples, from the Argentinean main growing area, was investigated during 2012/13 and 2013/14 using LC-MS/MS. Deoxynivalenol was found in all samples at concentrations varying between <LOQ (50μg/kg) and 9480μg/kg. Deoxynivalenol-3-glucoside was detected in 94% of the samples at concentrations ranging from <LOQ (50μg/kg) to 850μg/kg. Moreover, the acetylated derivatives were also detected but at lower frequency (49%). To the best of our knowledge, this is the first report of deoxynivalenol-3-glucoside in wheat in Argentina. All the commercial cultivars transformed deoxynivalenol to its glucosylated form at conversion rates between 6 and 22%. The results obtained alert of the potential risk present in durum wheat for Argentinean consumers but also show that some of the commercial cultivars currently on used could be promising candidates for breeding programs intended to obtained Fusarium head blight resistance.

Development and Validation of an Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry Method for Simultaneous Determination of Four Type B Trichothecenes and Masked Deoxynivalenol in Various Feed Products

A reliable and sensitive analytical method was developed for simultaneous determination of deoxynivalenol(DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), fusarenon X (FUS-X), and masked deoxynivalenol (deoxynivalenol-3-glucoside, D3G) in formula feed, concentrated feed, and premixed feed products. The method was based on an improved sample pretreatment with the commercially available HLB cartridges used for sample purification and enrichment followed by analysis using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Several key parameters including the extraction solvents, the positions of sample loading solvents, washing and elution solvents for HLB cartridges were carefully optimized to achieve optimal extraction and purification efficiencies. The established method was extensively validated by determining the linearity (R² ≥ 0.99), sensitivity (limit of quantification in the range of 0.08-4.85 μg/kg), recovery (79.3%-108.1%), precision (Intra-day RSDs ≤ 13.5% and Inter-day RSDs ≤ 14.9%), and then was successfully applied to determine the four type B trichothecenes and D3G in a total of 31 feed samples. Among them, 26 were contaminated with various mycotoxins at the levels of 2.1-864.5 μg/kg, and D3G has also been detected in 17 samples with the concentrations in the range of 2.1-34.8 μg/kg, proving the established method to be a valuable tool for type B trichothecenes and masked DON monitoring in complex feed matrices.

Modelling the anorectic potencies of food-borne trichothecenes by benchmark dose and incremental area under the curve methodology

Fusarium spp. fungi produce a spectrum of trichothecene mycotoxins that often simultaneously contaminate cereal grains. These have the potential to contribute jointly to adverse effects such as anorexia and emesis. For the purposes of risk assessment and regulation, it is desirable to assign toxic equivalency factors (TEFs) to each of these trichothecenes, as has been successfully done for anthropogenic toxicants such as polyhalogenated aromatic hydrocarbons. As a first step towards this end, we employed a mouse model to compare the anorectic potencies of deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), nivalenol (NIV), fusarenon-X (FUS-X), T-2 and HT-2 toxin (T-2 and HT-2) following oral exposure by gavage using two approaches. In the first approach, the US Environmental Protection Agency (US EPA) benchmark dose (BMD) method for continuous data was used to calculate the BMD relative to DON 2 h after dosing. The order of potency based on BMD values was: DON(1) ≈ 3-ADON(1) ≈ 15-ADON(1) < NIV(3) < HT-2(5) < FUS-X(9) << T-2(124). In a second approach, time course effects of each toxin at fixed doses were measured by calculating the incremental area under the curve (IAUC) over 16 h. DON caused significant feed refusal within the first 30 min after exposure, lasting only 3 h while for 3-ADON and 15-ADON, feed refusal lasted 6 h. NIV, FUS-X, T-2, and HT-2 toxins caused the longest duration of feed refusal, lasting up to 16 h. Based on IAUC values, the order of relative potency was as follows: DON(1) < 3-ADON(2) ≈ 15-ADON(2) < NIV(7) < FUS-X(10) << T-2(31) < HT-2(34). These results provide a foundation for developing consensus TEFs that will be amenable to future risk assessment of trichothecene mixtures.