Aflatoxins in Wheat Grains: Detection and Detoxification through Chemical, Physical, and Biological Means

Wheat (Triticum aestivum L.) is an essential food crop in terms of consumption as well as production. Aflatoxin exposure has a widespread public health impact in economically developing nations, so there is a need to establish preventive techniques for these high-risk populations. Pre-harvest and post-harvest practices are the two strategies used to control aflatoxin contamination, which include the use of genetically modified crops that show resistance against Aspergillus infection, the use of pesticides, changing the planting and harvesting time of crops, and physical, chemical, and biological methods. In this research, aflatoxin detection and quantification were performed in different wheat varieties to determine quantitative differences in comparison to the European Commission's limit of 4 ppb aflatoxins in wheat. TLC for qualitative and the ELISA kit method for quantitative analysis of aflatoxins were used. Out of 56 samples, 35 were found contaminated with aflatoxins, while the remaining 21 samples did not show any presence of aflatoxins. Out of the 35 contaminated samples, 20 samples showed aflatoxin contamination within the permissible limit, while the remaining 15 samples showed aflatoxin concentration beyond the permissible level, ranging from 0.49 to 20.56 ppb. After quantification, the nine highly contaminated wheat samples were detoxified using physical, chemical, and biological methods. The efficiency of these methods was assessed, and they showed a significant reduction in aflatoxins of 53-72%, 79-88%, and 80-88%, respectively. In conclusion, the difference in aflatoxin concentration in different wheat varieties could be due to genetic variations. Furthermore, biological treatment could be the method of choice for detoxification of aflatoxins in wheat as it greatly reduced the aflatoxin concentration with no harmful effect on the quality of the grains.

The C-8-S-isomers of ergot alkaloids - a review of biological and analytical aspects

Ergot alkaloids are secondary metabolites that are produced by fungi and contaminate cereal crops and grasses. The ergot alkaloids produced by Claviceps purpurea are the most abundant worldwide. The metabolites exist in two configurations, the C-8-R-isomer (R-epimer) and the C-8-S-isomer (S-epimer). These two configurations can interconvert to one another. Ergot alkaloids cause toxic effects after consumption of ergot-contaminated food and feed at various concentrations. For bioactivity reasons, the C-8-R-isomers have been studied to a greater extent than the C-8-S-isomer since the C-8-S-isomers were considered biologically inactive. However, recent studies suggest the contrary. Analytical assessment of ergot alkaloids now includes the C-8-S-isomers and high concentrations of specific C-8-S-isomers have been identified. The inclusion of the C-8-S-isomer in regulatory standards is reviewed. This review has identified that further research into the C-8-S-isomers of ergot alkaloids is warranted. In addition, the inclusion of the C-8-S-isomers into regulatory recommendations worldwide for food and feed should be implemented. The objectives of this review are to provide an overview of historic and current studies that have assessed the C-8-S-isomers. Specifically, this review will compare the C-8-R-isomers to the C-8-S-isomers with an emphasis on the biological activity and analytical assessment.

Determination of Multimycotoxin in Cereal-Based Products Sold in Open-Air Markets

In this study, a total of 140 cereal-based foods sold in temporary open-air markets were analyzed by LC-MS/MS for aflatoxin B₁, B₂, G₁, G₂, ochratoxin (OTA), zearalenone (ZEN), deoxynivalenol (DON), fumonisin B₁, fumonisin B₂, citrinin (CIT), HT-2, and T-2 toxins. Breakfast cereals (n:27), cornmeal (n:41), extruded maize (n:32), and oatmeal (n:40) purchased from these alternative shopping areas created to meet the food needs of low-income people in the suburbs formed the sample set of the study. These foods, which are sold in areas that are out of legal control and greatly affected by external environmental conditions, are more open to health risks. Mycotoxins, chemicals of a biological origin, are some of the most important of these risks. In terms of public health, it is important to investigate the presence of mycotoxins in foods, which can cause acute and chronic diseases such as immunosuppression, genotoxic, estrogenic, teratogenic effect, cancer, and liver and kidney dysfunctions. Grain-based foods are often contaminated with a large number of mycotoxins, but legal regulations have not been prepared that consider the health risks associated with the co-existence of mycotoxins. Many of the studies have focused on the presence of a single mycotoxin and the risks it poses. As a result, aflatoxin B₁ levels in 28.57% of the samples and total aflatoxin (B₁ + B₂ + G₁ + G₂) levels in 26.43% of the samples were determined to exceed the limits defined in the "Turkish Food Codex Contaminants Regulation". Citrinin could not be detected in any of the samples. The rate of mycotoxin occurrences above the limit of detection (LOD) in grain-based food samples ranged from 22.86% to 99.29%. Total aflatoxin (TAF) + Total Fumonisin (FUM) were found in 83.57% of the samples; TAF + FUM + OTA in 82.14%; TAF + FUM + OTA + T-2 in 44.29%; TAF + FUM + OTA + DON + HT-2, TAF + FUM + OTA + DON + T-2, and TAF + FUM + OTA + DON + ZEN in 22.86% of the samples.

Type B Trichothecenes in Cereal Grains and Their Products: Recent Advances on Occurrence, Toxicology, Analysis and Post-Harvest Decontamination Strategies

Type B trichothecenes (deoxynivalenol, nivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol) and deoxynivalenol-3-glucoside (DON-3G) are secondary toxic metabolites produced mainly by mycotoxigenic Fusarium fungi and have been recognized as natural contaminants in cereals and cereal-based foods. The latest studies have proven the various negative effects of type B trichothecenes on human health. Due to the widespread occurrence of Fusarium species, contamination by these mycotoxins has become an important aspect for public health and agro-food systems worldwide. Hence, their monitoring and surveillance in various foods have received a significant deal of attention in recent years. In this review, an up-to-date overview of the occurrence profile of major type B trichothecenes and DON-3G in cereal grains and their toxicological implications are outlined. Furthermore, current trends in analytical methodologies for their determination are overviewed. This review also covers the factors affecting the production of these mycotoxins, as well as the management strategies currently employed to mitigate their contamination in foods. Information presented in this review provides good insight into the progress that has been achieved in the last years for monitoring type B trichothecenes and DON-3G, and also would help the researchers in their further investigations on metabolic pathway analysis and toxicological studies of these Fusarium mycotoxins.

Zearalenone promotes follicle development through activating the SIRT1/PGC-1α signaling pathway in the ovaries of weaned gilts

This study aimed to investigate the effect of zearalenone (ZEA) exposure on follicular development in weaned gilts, and its mechanism based on the silent information regulator 1 (SIRT1)/peroxisome proliferator-activated receptor-γ co-activator 1α (PGC-1α) signaling pathway. A total of 32 healthy female weaned piglets (Landrace × Yorkshire × Duroc) with an average body weight of 12.39 ± 0.24 kg were randomly allotted to a basal diet supplemented with 0, 0.15, 1.5, or 3.0 mg/kg ZEA for a 32-d feeding test. Blood and ovarian samples were obtained at the end of the experiment to determine serum toxin concentrations, ovarian histology, and the expressions of proliferating cell nuclear antigen (PCNA) and SIRT1/PGC-1α signaling pathway-related genes. Results showed that the vulva area, serum concentrations of ZEA, α-zearalenol and β-zearalenol, the thickness of the growing follicular layer, and the diameter of the largest growing follicles, as well as the expressions of SIRT1, PGC-1α, estrogen-related receptor α (ERRα), ATP synthase subunit beta (ATP5B), and PCNA, increased linearly (P < 0.05) with increasing dietary ZEA, whereas the thickness of the primordial follicle layer decreased linearly (P < 0.05). Immunohistochemical analysis showed that the immunoreactive substances of SIRT1 and PGC-1α in the ovaries enhanced with the increasing dietary ZEA (P < 0.05). In addition, the thickness of the growing follicular layer and the diameter of the largest growing follicle were positively correlated with relative mRNA and protein expressions of SIRT1, PGC-1α, ERRα, ATP5B, and PCNA (P < 0.05). However, the thickness of the primordial follicle layer was negatively correlated with the mRNA and protein expression of SIRT1, PGC-1α, ERRα, ATP5B, and PCNA (P < 0.05). Interestingly, the 1.5 mg/kg ZEA treatment had highly hyperplastic follicles, whereas 3.0 mg/kg ZEA resulted in a large number of follicular atresia, which indicated that low-dose ZEA exposure accelerated follicular proliferation, while high-dose ZEA promoted follicular atresia, although the critical value interval needs further confirmation. Results provide a theoretical basis for finding the therapeutic target of ZEA-induced reproductive disorders in weaned gilts.

Review of occurrence of mycotoxins in Serbian food items in the period from 2005 to 2022

This paper aimed to review the publications on mycotoxins' presence in cereals and foodstuffs originated from the Serbian market covering the period from 2005 to 2022. The review covers all the important steps in mycotoxins analysis including sampling, sample preparation, instrumental analysis, and concentration ranges in which the mycotoxins were found. Also, the results were interpreted from the European Union regulation point of view. The review emphasizes the importance of multi-mycotoxins analysis for determining the simultaneous presence of mycotoxins that can negatively affect the Serbian human population. The most frequently used instrumental technique in the mycotoxin analysis of Serbian products was the Enzyme-Linked Immunosorbent Assay followed by the Ultra-High Performance Liquid Chromatography coupled with triple quadrupole mass spectrometry. Most of the studies undertaken in Serbia until now investigated a few groups of matrices such as wheat, maize, milk, and dairy products. Only a few studies involved specific matrices such as nuts, dried fruits, biscuits, cookies, and spices. The review showed that contamination of milk and dairy products with aflatoxin M1 (AFM1), occurred at the very beginning of 2013, was the major health issue related to the population health. The contamination of milk and dairy products with the AFM1 was a consequence of maize contamination with aflatoxins which occurred in the year 2012, characterized by drought conditions. The studies dealing with the analysis of masked and emerging mycotoxins are rare and more attention should be paid to monitoring the presence of these types of mycotoxins in foodstuffs from Serbia.

Review of occurrence of mycotoxins in Serbian food items in the period from 2005 to 2022

This paper aimed to review the publications on mycotoxins' presence in cereals and foodstuffs originated from the Serbian market covering the period from 2005 to 2022. The review covers all the important steps in mycotoxins analysis including sampling, sample preparation, instrumental analysis, and concentration ranges in which the mycotoxins were found. Also, the results were interpreted from the European Union regulation point of view. The review emphasizes the importance of multi-mycotoxins analysis for determining the simultaneous presence of mycotoxins that can negatively affect the Serbian human population. The most frequently used instrumental technique in the mycotoxin analysis of Serbian products was the Enzyme-Linked Immunosorbent Assay followed by the Ultra-High Performance Liquid Chromatography coupled with triple quadrupole mass spectrometry. Most of the studies undertaken in Serbia until now investigated a few groups of matrices such as wheat, maize, milk, and dairy products. Only a few studies involved specific matrices such as nuts, dried fruits, biscuits, cookies, and spices. The review showed that contamination of milk and dairy products with aflatoxin M1 (AFM1), occurred at the very beginning of 2013, was the major health issue related to the population health. The contamination of milk and dairy products with the AFM1 was a consequence of maize contamination with aflatoxins which occurred in the year 2012, characterized by drought conditions. The studies dealing with the analysis of masked and emerging mycotoxins are rare and more attention should be paid to monitoring the presence of these types of mycotoxins in foodstuffs from Serbia.

Agronomic Factors Influencing the Scale of Fusarium Mycotoxin Contamination of Oats

Seven agronomic factors (crop season, farming system, harvest date, moisture, county, oat variety, and previous crop) were recorded for 202 oat crops grown across Ireland, and samples were analysed by LC-MS/MS for four major Fusarium mycotoxins: deoxynivalenol (DON), zearalenone (ZEN), T-2 toxin and HT-2 toxin. Type A trichothecenes were present in 62% of crops, with 7.4% exceeding European regulatory limits. DON (6.4%) and ZEN (9.9%) occurrences were relatively infrequent, though one and three samples were measured over their set limits, respectively. Overall, the type of farming system and the previous crop were the main factors identified as significantly influencing mycotoxin prevalence or concentration. Particularly, the adherence to an organic farming system and growing oats after a previous crop of grass were found to decrease contamination by type A trichothecenes. These are important findings and may provide valuable insights for many other types of cereal crops as Europe moves towards a much greater organic-based food system.

Naturally Occurring Fusarium Species and Mycotoxins in Oat Grains from Manitoba, Canada

Fusarium head blight (FHB) can lead to dramatic yield losses and mycotoxin contamination in small grain cereals in Canada. To assess the extent and severity of FHB in oat, samples collected from 168 commercial oat fields in the province of Manitoba, Canada, during 2016-2018 were analyzed for the occurrence of Fusarium head blight and associated mycotoxins. Through morphological and molecular analysis, F. poae was found to be the predominant Fusarium species affecting oat, followed by F. graminearum, F. sporotrichioides, F. avenaceum, and F. culmorum. Deoxynivalenol (DON) and nivalenol (NIV), type B trichothecenes, were the two most abundant Fusarium mycotoxins detected in oat. Beauvericin (BEA) was also frequently detected, though at lower concentrations. Close clustering of F. poae and NIV/BEA, F. graminearum and DON, and F. sporotrichioides and HT2/T2 (type A trichothecenes) was detected in the principal component analysis. Sampling location and crop rotation significantly impacted the concentrations of Fusarium mycotoxins in oat. A phylogenetic analysis of 95 F. poae strains from Manitoba was conducted using the concatenated nucleotide sequences of Tef-1α, Tri1, and Tri8 genes. The results indicated that all F. poae strains belong to a monophyletic lineage. Four subgroups of F. poae strains were identified; however, no correlations were observed between the grouping of F. poae strains and sample locations/crop rotations.

Natural Co-Occurrence of Multiple Mycotoxins in Unprocessed Oats Grown in Ireland with Various Production Systems

The natural co-occurrence of 42 mycotoxins was investigated in unprocessed oat grains grown in Ireland. The sample set included a total of 208 oat crops harvested during 2015–2016 and produced using conventional, organic, or gluten free farming systems. A range of different toxins was identified, including the major type A (neosolaniol, HT-2 and T-2 toxins, T-2 triol, and T-2-glucoside, co-occurring in 21 samples) and B trichothecenes (deoxynivalenol, nivalenol, and deoxynivalenol-3-glucoside), enniatins (B1, B, and A1, co-occurring in 12 samples), as well as beauvericin, alternariol, mycophenolic acid, and sterigmatocystin. The influences of sowing season, year, and production system were investigated, eventually indicating that the latter factor may have a higher impact than others on the production of certain mycotoxins in oats. The most frequently quantified compounds were HT-2 (51%) and T-2 (41%) toxins, with gluten free oats containing significantly lower concentrations of HT-2 compared to conventionally produced oats. Although the prevalence and concentrations of mycotoxin found in oat samples in this study should be substantially reduced by processing. However, as mycotoxin occurrence is clearly influenced by multiple factors, controlled field trials should be carried out to define optimal agronomic practices and mitigate mycotoxin production. Furthermore, this work highlights the need for regularly testing cereal-based foods with multi-residue analytical methods with wider specificities than the traditionally screened and regulated toxins, to generate knowledge on the occurrence of several mycotoxins that are, to date, rarely investigated.

Assessment of Deoxynivalenol in Wheat, Corn and Its Products and Estimation of Dietary Intake

The main goal of the present research was to explore the seasonal variation of deoxynivalenol (DON) in wheat, corn, and their products, collected during 2018-2019. Samples of 449 of wheat and products and 270 samples of corn and their products were examined using reverse-phase liquid chromatography with a UV detector. The findings of the present work showed that 104 (44.8%) samples of wheat and products from the summer season, and 91 (41.9%) samples from winter season were contaminated with DON (concentration limit of detections (LOD) to 2145 µg/kg and LOD to 2050 µg/kg), from summer and winter seasons, respectively. In corn and products, 87 (61.2%) samples from summer and 57 (44.5%) samples from winter season were polluted with DON with levels ranging from LOD to 2967 µg/kg and LOD to 2490 µg/kg, from the summer and winter season, respectively. The highest dietary intake of DON was determined in wheat flour 8.84 µg/kg body weight/day from the summer season, and 7.21 µg/kg body weight/day from the winter season. The findings of the work argued the need to implement stringent guidelines and create awareness among farmers, stakeholders, and traders of the harmful effect of DON. It is mostly observed that cereal crops are transported and stockpiled in jute bags, which may absorb moisture from the environment and produce favorable conditions for fungal growth. Therefore, these crops must store in polyethylene bags during transportation and storage, and moisture should be controlled. It is highly desirable to use those varieties that are more resistant to fungi attack. Humidity and moisture levels need to be controlled during storage and transportation.

Determination of 42 mycotoxins in oats using a mechanically assisted QuEChERS sample preparation and UHPLC-MS/MS detection

A method was developed and validated for the simultaneous determination of 42 mycotoxins in oats. The method includes all the mycotoxins listed under Commission Regulation 1881/2006 and Commission Recommendation 165/2013, the emerging mycotoxins (beauvericin, alternariol, alternariol-methyl-ether and enniatins), and two masked metabolites, namely deoxynivalenol-3-glucoside and T-2-glucoside. The method also focuses on a wide range of analytes of toxicological interest. The sample preparation involved extraction with an aqueous acetic acid solution and acetonitrile, followed by QuEChERS with mechanically assisted vibrational shaking. No further clean-up steps were employed, and analysis was performed using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Trueness ranged between 78% and 158%, while precision ranged from 1.7% to 49.9% under within-laboratory reproducibility conditions. Beside the high degree of accuracy and sample throughput provided, the method can be applied to a large number of compounds currently not regulated, thus generating knowledge and for risk assessment purposes.

Detection of mycotoxins and toxigenic fungi in cereal grains using vibrational spectroscopic techniques: a review

Nutrition-rich cereal grains and oil seeds are the major sources of food and feed for human and livestock, respectively. Infected by fungi and contaminated with mycotoxins are serious problems worldwide for cereals and oil seeds before and after harvest. The growth and development activities of fungi consume seed nutrients and destroy seed structures, leading to dramatic declines of crop yield and quality. In addition, the toxic secondary metabolites produced by these fungi pose a well-known threat to both human and animals. The existence of fungi and mycotoxins has been a redoubtable problem worldwide for decades but tends to be a severe food safety issue in developing countries and regions, such as China and Africa. Detection of fungal infection at an early stage and of mycotoxin contaminants, even at a small amount, is of great significance to prevent harmful toxins from entering the food supply chains worldwide. This review focuses on the recent advancements in utilising infrared spectroscopy, Raman spectroscopy, and hyperspectral imaging to detect fungal infections and mycotoxin contaminants in cereals and oil seeds worldwide, with an emphasis on recent progress in China. Brief introduction of principles, and corresponding shortcomings, as well as latest advances of each technique, are also being presented herein.

Effects of processing whole oats on the analysis and fate of mycotoxins and ergosterol

Grinding and dividing equipment were evaluated for their ability to comminute and divide ground oats in preparation for mycotoxin analysis. Four different grinders, using various settings, were evaluated for their ability to comminute oats and produce small particle sizes. Rotor beater type grinders produced the more desirable finer ground samples as compared to burr type mills. Four different division methods (manual scooping, rotary sample division, and two designs of gravity-fed dividers) were assessed for their ability to produce sub-samples with consistent particle size fraction distributions. No practical differences were observed on the particle size fraction distribution of test portions of finely ground oats produced using the four different division methods; therefore, no effects on mycotoxin analysis were anticipated. The effects of processing naturally contaminated whole oats on mycotoxin concentrations was also assessed. Laboratory scale dehulling, steaming, and kilning were examined. Dehulling showed the greatest impact and removed 60-100% of various Fusarium- and Alternaria-produced mycotoxins, as well as ergosterol, present on the naturally contaminated whole oats. Different from the other analytes studied, only 48% of the mycotoxin plant transformation product deoxynivalenol-3-glucoside was present in hulls and removed during dehulling. Steaming and kilning appeared to increase ergosterol in groats, as well as decrease deoxynivalenol and deoxynivalenol-3- glucoside. The observed inconsistent changes in concentrations of tentoxin after heat treatment of groats appeared to be due to sample heterogeneity.

Presence of Zearalenone in Cereal Grains and Its Exposure Risk Assessment in Indian Population

Zearalenone (ZEA) is a toxic metabolite of Fusarium genera that frequently contaminates cereal grains. India being a tropical country provides suitable conditions for fungal invasion to the cereals. In the absence of any regulatory limits for ZEA in India, the present study was carried out to analyze the contamination levels of ZEA in different cereal samples consumed by Indian population and its exposure assessment through intake. Out of 117 cereal samples comprising of wheat, rice, corn, and oats, 70 (84%) were found to be positive for ZEA contamination, among which 24 (33%) samples exceeded the permissible limits proposed by European Union when analyzed by high-performance liquid chromatography. The positive samples were further validated by Liquid Chromatography-Mass Spectroscopy (LC-MS) analysis. Based on the quantitative estimation of ZEA contamination in cereals and their daily consumption values, the probable daily intake of ZEA was found to be 16.9- and 7.9-fold higher in rice and wheat samples, respectively, than the tolerable daily intake prescribed by European Food Safety Authority. The presence of ZEA at high levels indicates a higher exposure risk for Indian population as wheat and rice are staple foods in India. Thus, there is an immediate need to set the permissible levels of ZEA in India to safeguard the health of 1.34 billion people. PRACTICAL APPLICATION: High levels of ZEA contaminated wheat and rice samples suggest that the consumers are at a greater exposure risk. The study will help the Indian regulatory bodies to set the permissible level of ZEA in different cereal grains so as to safeguard the health of common masses. This can happen by simply adopting to European Food Safety Authority standards or depending on the consumption pattern of food and its occurrence, the new safe limit can be prescribed in India like in other Asian countries.

Assessment of a Nutritional Rehabilitation Model in Two Modern Broilers and Their Jungle Fowl Ancestor: A Model for Better Understanding Childhood Undernutrition

This article is the first in a series of manuscripts to evaluate nutritional rehabilitation in chickens as a model to study interventions in children malnutrition (Part 1: Performance, Bone Mineralization, and Intestinal Morphometric Analysis). Inclusion of rye in poultry diets induces a nutritional deficit that leads to increased bacterial translocation, intestinal viscosity, and decreased bone mineralization. However, it is unclear the effect of diet on developmental stage or genetic strain. Therefore, the objective was to determine the effects of a rye diet during either the early or late phase of development on performance, bone mineralization, and intestinal morphology across three diverse genetic backgrounds. Modern 2015 (Cobb 500) broiler chicken, 1995 Cobb broiler chicken, and the Giant Jungle Fowl were randomly allocated into four different dietary treatments. Dietary treatments were (1) a control corn-based diet throughout the trial (corn-corn); (2) an early phase malnutrition diet where chicks received a rye-based diet for 10 days, and then switched to the control diet (rye-corn); (3) a malnutrition rye-diet that was fed throughout the trial (rye-rye); and (4) a late phase malnutrition diet where chicks received the control diet for 10 days, and then switched to the rye diet for the last phase (corn-rye). At 10 days of age, chicks were weighed and diets were switched in groups 2 and 4. At day 20 of age, all chickens were weighed and euthanized to collect bone and intestinal samples. Body weight, weight gain, and bone mineralization were different across diet, genetic line, age and all two- and three-way interactions (P < 0.05). Overall, Jungle Fowl were the most tolerant to a rye-based diet, and both the modern and 1995 broilers were significantly affected by the high rye-based diet. However, the 1995 broilers consuming the rye-based diet appeared to experience more permanent effects when compared with the modern broiler. The results of this study suggest that chickens have a great potential as a nutritional rehabilitation model in human trials. The 1995 broilers line was an intermediate genetic line between the fast growing modern line and the non-selected Jungle Fowl line, suggesting that it would be the most appropriate model to study for future studies.

Occurrence of ergot alkaloids in wheat from Albania

The occurrence of ergot alkaloids in wheat harvested in Albania was investigated. A total of 71 samples of winter wheat collected in 2014 and 2015 were analysed for the 12 most important ergot alkaloids using liquid chromatography-tandem mass spectrometry. In the harvesting year 2014, 48.6% of samples were contaminated with ergot alkaloids, whereas in 2015 only 19.4% of samples were contaminated. In 2014, the concentrations of total ergot alkaloids ranged from 17.3 to 975.4 μg kg^-1, and in 2015 they ranged from 10.3 to 390.5 μg kg^-1. The samples contained from one to nine ergot alkaloids. The most frequent were ergometrine, ergosine and ergocristine, and the least frequent were ergocryptine, ergocryptinine and ergocorninine.

Development and validation of an UHPLC-MS/MS method for the determination of mycotoxins in grass silages

An ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) multi-mycotoxin analytical method was developed to simultaneously identify and quantify 20 mycotoxins in grass silages, inclusive of mycotoxins that are currently regulated in European Union feeds. Extraction of mycotoxins from dried grass silages was performed using of a modified QuEChERS extraction employing an acidified aqueous extraction (0.1 N HCl) with no further clean-up. Following chromatographic separation, analytes were detected using a fast polarity-switching MS/MS method that allowed both positive and negative ions to be analysed from a single injection, thus the reducing time and cost of analysis. The limits of detection and quantification ranged between 3 µg kg(-1) DM (aflatoxin B1, beauvericin and enniatin A and A1) and 200 µg kg(-1) DM (deoxynivalenol), and between 10 µg kg(-1) DM (aflatoxin B1, beauvericin and enniatin A1) and 500 µg kg(-1) DM (deoxynivalenol), respectively. Inter-assay accuracy and precision ranged between 90% and 107% and between 3.9% and 15.0% CV, respectively. The accuracy of the method was assessed through the application to a range of incurred samples in an inter-laboratory study.

Aflatoxins in cereals: worldwide occurrence and dietary risk assessment

The worldwide occurrence of aflatoxins (AFB1, AFB2, AFG1, AFG2), genotoxic mycotoxins, in raw maize, rice, sorghum and wheat samples collected since the year 2000 was evaluated using published data and occurrence data from the GEMS/Food database (https://extranet.who.int/gemsfood). Dietary risk assessments were conducted using GEMS/Food total aflatoxin occurrence and food consumption data obtained from the 17 Cluster Diets. Risk characterisation arising from aflatoxin exposure was conducted using both cancer risk and margin of exposure (MOE) approaches. A total of 89 publications were retrieved from the literature, reporting data related to 18,097 samples, of which 37.6% were positive for at least one aflatoxin. The total upper bound (UB) mean for all samples analysed was 13.6 μg/kg, and was higher for rice (24.6 μg/kg) and sorghum (25.9 μg/kg). Of data related to the analysis of 4,536 samples reported to GEMS/Food database, 12.7% were positive for at least one aflatoxin. The total UB mean was 1.9 μg/kg, and was higher for rice (2.4 μg/kg) and maize (1.6 μg/kg). Total intakes ranged from 3.0 ng/kg bw/day (Cluster C11) to 17.1 ng/kg bw/day (Cluster C09). On average, the consumption of rice contributed to 41.6% of the total aflatoxin intake in all clusters, followed by wheat (35.4%), maize (21.2%) and sorghum (1.8%). The lowest cancer risk was found in cluster C11 (0.057 cancers/year/105 individuals), and the highest in cluster C09 (0.467 cancers/year/105 individuals). MOE ranged from 56 (C11) to 10 (C09), indicating a potential risk to consumers. These results highlight the need for continuous action by health authorities to decrease aflatoxin contamination in cereals, as they are staple foods in diets worldwide. These actions include the enforcement of code of practices at the national level and the establishment of maximum contamination levels by the Codex System.

Occurrence of Ergot and Ergot Alkaloids in Western Canadian Wheat and Other Cereals

A new method was developed to analyze 10 ergot alkaloids in cereal grains. Analytes included both "ine" and "inine" type ergot alkaloids. Validation of the method showed it performed with good accuracy and precision and that minor enhancement due to matrix effects was present during LC-MS/MS analysis, but was mitigated by use of an internal standard. The method was used to survey durum and wheat harvested in 2011, a year in which ergot infection was particularly widespread in western Canada. A strong linear relationship between the concentration of ergot alkaloids and the presence of ergot sclerotia was observed. In addition, shipments of cereals from 2010-2012 were also monitored for ergot alkaloids. Concentrations of total ergot alkaloids in shipments were lower than observed in harvest samples, and averaged from 0.065 mg/kg in barley to 1.14 mg/kg in rye. In shipments, the concentration of ergot alkaloids was significantly lower in wheat of higher grades.

Challenging conventional risk assessment with respect to human exposure to multiple food contaminants in food: A case study using maize

Mycotoxins and heavy metals are ubiquitous in the environment and contaminate many foods. The widespread use of pesticides in crop production to control disease contributes further to the chemical contamination of foods. Thus multiple chemical contaminants threaten the safety of many food commodities; hence the present study used maize as a model crop to identify the severity in terms of human exposure when multiple contaminants are present. High Content Analysis (HCA) measuring multiple endpoints was used to determine cytotoxicity of complex mixtures of mycotoxins, heavy metals and pesticides. Endpoints included nuclear intensity (NI), nuclear area (NA), plasma membrane permeability (PMP), mitochondrial membrane potential (MMP) and mitochondrial mass (MM). At concentrations representing legal limits of each individual contaminant in maize (3ng/ml ochratoxin A (OTA), 1μg/ml fumonisin B1 (FB1), 2ng/ml aflatoxin B1 (AFB1), 100ng/ml cadmium (Cd), 150ng/ml arsenic (As), 50ng/ml chlorpyrifos (CP) and 5μg/ml pirimiphos methyl (PM), the mixtures (tertiary mycotoxins plus Cd/As) and (tertiary mycotoxins plus Cd/As/CP/PM) were cytotoxic for NA and MM endpoints with a difference of up to 13.6% (p≤0.0001) and 12% (p≤0.0001) respectively from control values. The most cytotoxic mixture was (tertiary mycotoxins plus Cd/As/CP/PM) across all 4 endpoints (NA, NI, MM and MMP) with increases up to 61.3%, 23.0%, 61.4% and 36.3% (p≤0.0001) respectively. Synergy was evident for two endpoints (NI and MM) at concentrations contaminating maize above legal limits, with differences between expected and measured values of (6.2-12.4% (p≤0.05-p≤0.001) and 4.5-12.3% (p≤0.05-p≤0.001) for NI and MM, respectively. The study introduces for the first time, a holistic approach to identify the impact in terms of toxicity to humans when multiple chemical contaminants are present in foodstuffs. Governmental regulatory bodies must begin to contemplate how to safeguard the population when such mixtures of contaminants are found in foods and this study starts to address this critical issue.

Analysis of Ergot Alkaloids

The principles and application of established and newer methods for the quantitative and semi-quantitative determination of ergot alkaloids in food, feed, plant materials and animal tissues are reviewed. The techniques of sampling, extraction, clean-up, detection, quantification and validation are described. The major procedures for ergot alkaloid analysis comprise liquid chromatography with tandem mass spectrometry (LC-MS/MS) and liquid chromatography with fluorescence detection (LC-FLD). Other methods based on immunoassays are under development and variations of these and minor techniques are available for specific purposes.

By-products of grain cleaning: an opportunity for rapid sampling and screening of wheat for mycotoxins

By-products of cereal grain cleaning were analysed for a number of mycotoxins. Deoxynivalenol (DON) was the most frequently detected in by-products from commercial-scale cleaning procedures (maximum 2.94 mg/kg), followed by zearalenone (ZEA; maximum 0.045 mg/kg) and ochratoxin A (OTA; maximum 0.019 mg/kg). These three mycotoxins were also the most frequently detected in four different fractions collected from wheat run through a dockage tester, a piece of equipment used in the Canadian inspection process to separate material other than grain from wheat. Concentrations of mycotoxins were highest in the ‘light dockage’ fraction that contained dust and roughage such as glumes, fragments of stem, or rachis. Mycotoxin concentrations in this fraction reached up to 32 mg/kg (DON), 0.532 mg/kg (ZEA), and 0.249 mg/kg (OTA). Concentrations of DON in light dockage were significantly correlated with concentrations in whole grain that was un-cleaned or had undergone basic cleaning, indicating that the light dockage fraction could be used as a readily available matrix for the rapid screening of DON in wheat. This would eliminate the time required for additional sampling and preparation of whole grain, and move towards a truly rapid method for the screening of DON in wheat.

Untargeted screening of secondary metabolites in fungal cultures and samples from mouldy indoor environments by time-of-flight mass spectrometry

Nowadays, complaints about poor indoor air quality have become common. The variety of indoor air health problems include chronic fatigue, allergy, skin and eye irritation, and can be caused by several factors including fungi and their metabolites present in a building. The objective of this study was to establish a method for untargeted analysis of secondary fungal metabolites in indoor environments. As a detection technique, time-of-flight mass spectrometry was chosen, as it provided mass accuracy and higher sensitivity in full scan acquisition mode compared to tandem mass spectrometers. The method was first applied to fungal cultures, namely Penicillium brevicompactum and Chaetomium murorum, which were isolated from mouldy houses and grown on building materials under laboratory conditions for 7-21 days. Following the proposed strategy based on accurate mass measurement and post-acquisition data processing using principal component analysis, roquefortine C, brevianamide A and mycophenolic acid were identified in Penicillium sp., while chaetoglobosin A was found to be produced by Chaetomium sp. Subsequently, samples from mouldy inhabited buildings were analysed using the developed method. The actual presence of meleagrin was demonstrated in mouldy indoor environment. Applying the method to air and dust samples collected in these mouldy buildings, no metabolites were detected possibly due to generally low concentrations in these types of samples.

Determination of T-2 and HT-2 toxins in food and feed: an update

Based on the recent scientific opinion of the European Food Safety Authority (EFSA) Panel on Contaminants in the Food Chain on the risks to human and animal health related to the presence of T-2 and HT-2 toxins in food and feed that was published by EFSA in the EFSA Journal, this article provides an update on the determination of these Fusarium mycotoxins. After a brief introduction into the chemistry of these toxins, both chromatographic and immuno-analytical methods are discussed for the determination of these type A trichothecenes. During the last decade, liquid chromatography with (tandem) mass spectrometry has become the most frequently used method for the determination of T-2 and HT-2 toxins, often within a multi-analyte approach. However, complex matrices and the resulting signal suppression effects, as observed particularly in electrospray-mass spectrometry methods owing to matrix effects, may require careful optimisation of clean-up, usage of matrix matched standards, or e.g. the use of internal standards. For specific purposes where extremely low limits of quantification are needed, e.g. for the analysis of duplicate diets, a dedicated gas chromatography method with multistage mass spectrometry has become available. Other novel analytical approaches to determine T-2 and HT-2 toxins in food and feed include biosensor-based methods in surface plasmon resonance and electrochemical formats, as well as DNA microchip assays. For rapid screening, several immunochemical methods (mostly ELISAs) have become available and some are sold as commercial test kits. Whereas these methods work fast, cross-reactivities with other trichothecenes can have an undesired effect on their accuracy. While proficiency tests including T-2 and HT-2 toxins have been carried out, none of the chromatographic or immunochemical methods have been formally validated in interlaboratory validation studies. There are no certified reference materials available for T-2 and HT-2 toxins.

Critical evaluation of LC-MS-based methods for simultaneous determination of deoxynivalenol, ochratoxin A, zearalenone, aflatoxins, fumonisins and T-2/HT-2 toxins in maize

The results of a proficiency test for the LC-MS/(MS) determination of up to 11 mycotoxins (aflatoxins B1, B2, G1 and G2, fumonisins B1 and B2, ochratoxin A, deoxynivalenol, T-2 and HT-2 toxins and zearalenone) in maize were evaluated to identify possible strengths and weaknesses of various methodologies used by the 41 participating laboratories. The majority of laboratories (56%) used mixtures of acetonitrile:water for extraction. Other laboratories used methanol:water mixtures (17%) or performed two consecutive extractions with phosphate buffer solution (PBS) followed by methanol (15%). Few laboratories used mixtures of acetonitrile:water:methanol (7%), water:ethyl acetate (2.5%) or PBS alone (2.5%). The majority of laboratories (58%) used a clean-up step prior to chromatography. The remaining laboratories analysed crude extracts (37%) or used a mixed approach (5%). The amount of sample equivalent injected into LC-MS/(MS) ranged between 0.1-303 mg for purified extracts and 0.08-20 mg for directly analysed crude extracts. External (54%), matrix-matched (22%) or stable isotope-labelled internal standards calibration (24%) were used for toxin quantification. In general, extraction mixtures of water with acetonitrile, methanol or both provided good results for quantitative extraction of mycotoxins from maize. Laboratories using sample extract clean-up reported acceptable results for the majority of mycotoxins. Good results were also obtained by laboratories that analysed crude extracts although a high variability of results was observed for all tested mycotoxins. Matrix-matched calibration or isotope-labelled internal standards efficiently compensated matrix effects whereas external calibration gave reliable results by injecting ≤10 mg of matrix equivalent amounts. Unacceptable high recovery and high variability of fumonisin results were obtained by the majority of laboratories, which could not be explained and thus require further investigation. These findings provide the basis for the optimization and selection of methods to be used in future interlaboratory validation studies to derive their performance characteristics for simultaneous determination of mycotoxins in maize.

Monitoring of Fusarium trichothecenes in Canadian cereal grain shipments from 2010 to 2012

A method involving dry grinding, rotary sample dividing, and gas chromatography-mass spectrometry was evaluated for the analysis of eight Fusarium trichothecenes in cereal grains. Processing of whole cereal grains by the method produced representative test portions for the analysis of deoxynivalenol (DON). Method validation data, as well as the successful participation in various international proficiency tests, demonstrated the analytical method produced accurate and precise results. The evaluated method was used to monitor DON, 3- and 15-acetyldeoxynivalenol, nivalenol (NIV), T-2 toxin, HT-2 toxin, diacetoxyscirpenol, and fusarenon-X in shipments of Canadian wheat, durum, barley, corn, rye, and oats transported between August 1, 2010, and July 31, 2012. DON was the most frequently measured trichothecene, found in 231 of the 303 samples at concentrations up to 2.34 mg/kg; NIV was the next most frequently observed trichothecene, but its occurrence was limited to barley. Concentrations of DON were significantly associated with wheat class and grade. The median DON concentration in durum (0.09 mg/kg) was lower than that for hard red spring (0.21 mg/kg). Lower grades of wheat also contained higher median concentrations of DON than higher grades, supporting the current use of Fusarium damaged kernels as a grading factor to manage DON.

Multi-mycotoxin analysis of finished grain and nut products using high-performance liquid chromatography-triple-quadrupole mass spectrometry

Mycotoxins in foods have long been recognized as potential health hazards due to their toxic and carcinogenic properties. A simple and rapid method was developed to detect 26 mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, and ergot alkaloids) in corn, rice, wheat, almond, peanut, and pistachio products using high-performance liquid chromatography-triple-quadrupole mass spectrometry. Test portions of homogenized grain or nut products were extracted with acetonitrile/water (85:15, v/v), followed by high-speed centrifugation and dilution with water. Mean recoveries (± standard deviations) were 84 ± 6, 89 ± 6, 97 ± 9, 87 ± 12, 104 ± 16, and 92 ± 18% from corn, rice, wheat, almond, peanut, and pistachio products, respectively, and the matrix-dependent instrument quantitation limits ranged from 0.2 to 12.8 μg/kg, depending on the mycotoxin. Matrix effects, as measured by the slope ratios of matrix-matched and solvent-only calibration curves, revealed primarily suppression and were more pronounced in nuts than in grains. The measured mycotoxin concentrations in 11 corn and wheat reference materials were not different from the certified concentrations. Nineteen mycotoxins were identified and measured in 35 of 70 commercial grain and nut products, ranging from 0.3 ± 0.1 μg/kg (aflatoxin B1 in peanuts) to 1143 ± 87 μg/kg (fumonisin B1 in corn flour). This rapid and efficient method was shown to be rugged and effective for the multiresidue analysis of mycotoxins in finished grain and nut products.

Photochemical trans-/cis-isomerization and quantitation of zearalenone in edible oils

The emphasis of the present work was to investigate the photochemical conversion of trans- to cis-zearalenone in edible oils under real-life conditions. For quantitation purposes a cis-zearalenone standard was synthesized and characterized for its identity and purity (≥95%) by (1)H NMR, X-ray crystallography, HPLC fluorescence and mass spectrometric detection. In a sample survey of 12 edible oils (9 corn oils, 3 hempseed oils) from local supermarkets all corn oils contained trans-zearalenone (median 194 μg/kg), but no cis-zearalenone was detected. For alteration studies trans-zearalenone contaminated corn oils were exposed to sunlight over 4 and 30 weeks, revealing an obvious shift toward cis-zearalenone up to a cis/trans ratio of 9:1 by storage in colorless glass bottles. Irradiation experiments of trans-zearalenone in different organic solvents confirmed the preferred formation of cis-zearalenone possibly caused by entropic effects rather than by enthalpic entities as investigated by quantum chemical and classical force field simulations.

Multiclass mycotoxin analysis in food, environmental and biological matrices with chromatography/mass spectrometry

Mold metabolites that can elicit deleterious effects on other organisms are classified as mycotoxins. Human exposure to mycotoxins occurs mostly through the intake of contaminated agricultural products or residues due to carry over or metabolite products in foods of animal origin such as milk and eggs, but can also occur by dermal contact and inhalation. Mycotoxins contained in moldy foods, but also in damp interiors, can cause diseases in humans and animals. Nephropathy, various types of cancer, alimentary toxic aleukia, hepatic diseases, various hemorrhagic syndromes, and immune and neurological disorders are the most common diseases that can be related to mycotoxicosis. The absence or presence of mold infestation and its propagation are seldom correlated with mycotoxin presence. Mycotoxins must be determined directly, and suitable analytical methods are necessary. Hundreds of mycotoxins have been recognized, but only for a few of them, and in a restricted number of utilities, a maximum acceptable level has been regulated by law. However, mycotoxins seldom develop alone; more often various types and/or classes form in the same substrate. The co-occurrence might render the individual mycotoxin tolerance dose irrelevant, and therefore the mere presence of multiple mycotoxins should be considered a risk factor. The advantage of chromatography/mass spectrometry (MS) is that many compounds can be determined and confirmed in one analysis. This review illustrates the state-of-the-art of mycotoxin MS-based analytical methods for multiclass, multianalyte determination in all the matrices in which they appear. A chapter is devoted to the history of the long-standing coexistence and interaction among humans, domestic animals and mycotoxicosis, and the history of the discovery of mycotoxins. Quality assurance, although this topic relates to analytical chemistry in general, has been also examined for mycotoxin analysis as a preliminary to the systematic literature excursus. Sample handling is a crucial step to devise a multiclass analytical method; so when possible, it has been treated separately for a better comparison before tackling the instrumental part of the whole analytical method. This structure has resulted sometimes in unavoidable redundancies, because it was also important to underline the interconnection. Most reviews do not deal with all the possible mycotoxin sources, including the environmental ones. The focus of this review is the analytical methods based on MS for multimycotoxin class determination. Because the final purpose to devise multimycotoxin analysis should be the assessment of the danger to health of exposition to multitoxicants of natural origin (and possibly also the interaction with anthropogenic contaminants), therefore also the analytical methods for environmental relevant mycotoxins have been thoroughly reviewed. Finally, because the best way to shed light on actual risk assessment could be the individuation of exposure biomarkers, the review covers also the scarce literature on biological fluids.

Developments in mycotoxin analysis: an update for 2010-2011

This review highlights developments in mycotoxin analysis and sampling over a period between mid-2010 and mid-2011. It covers the major mycotoxins: aflatoxins, Alternaria toxins, ergot alkaloids, fumonisins, ochratoxin, patulin, trichothecenes, and zearalenone. Analytical methods for mycotoxins continue to be developed and published. Despite much interest in immunochemical methods and in the rapid development of LC-MS methodology, more conventional methods, sometimes linked to novel clean-up protocols, have also been the subject of research publications over the above period. Occurrence of mycotoxins falls outside the main focus of this review; however, where relevant to analytical method development, this has been mentioned.

Development and in-house validation of a robust and sensitive solid-phase extraction liquid chromatography/tandem mass spectrometry method for the quantitative determination of aflatoxins B1, B2, G1, G2, ochratoxin A, deoxynivalenol, zearalenone, T-2 and HT-2 toxins in cereal-based foods

A sensitive and robust liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed for the simultaneous determination of aflatoxins (B(1), B(2), G(1), G(2)), ochratoxin A, deoxynivalenol, zearalenone, T-2 and HT-2 toxins in cereal-based foods. Samples were extracted with a mixture of acetonitrile/water (84:16, v/v) and cleaned up through a polymeric solid-phase extraction column. Detection and quantification of the nine mycotoxins were performed by reversed-phase liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry (LC/ESI-MS/MS), using fully (13)C-isotope-labelled mycotoxins as internal standards. The method was validated in-house for five different cereal processed products, namely barley, oat and durum wheat flours, rye- and wheat-based crisp bread. Recoveries and repeatability of the whole analytical procedure were evaluated at contamination levels encompassing the EU maximum permitted levels for each tested mycotoxin. Recoveries ranged from 89 to 108% for deoxynivalenol, from 73 to 114% for aflatoxins, from 85 to 114% for T-2 and HT-2 toxins, from 64 to 97% for zearalenone, from 74 to 102% for ochratoxin A. Relative standard deviations were less than 16% for all tested mycotoxins and matrices. Limits of detection (signal-to-noise ratio 3:1) ranged from 0.1 to 59.2 µg/kg. The trueness of the results obtained by the proposed method was demonstrated by analysis of reference materials for aflatoxins, deoxynivalenol, zearalenone. The use of inexpensive clean-up cartridges and the increasing availability of less expensive LC/MS/MS instrumentation strengthen the potential of the proposed method for its effective application for reliable routine analysis to assess compliance of tested cereal products with current regulation.