Scientific Opinion on the risk for public and animal health related to the presence of sterigmatocystin in food and feed

Neurotoxicological Effects of Some Mycotoxins on Humans Health and Methods of Neuroprotection

Food contamination with mycotoxin-producing fungi increases the risk of many diseases, including neurological diseases closely related to the neurotoxicity of these toxins. Based on the latest literature data, we presented the association of common Fusarium mycotoxins with neurological diseases. Articles from 2001 to 2024 were analyzed. The mechanisms underlying the neurotoxicity of the described mycotoxins were presented. They are mainly related to the increase in oxidative stress in neuronal cells, which leads to higher levels of pro-inflammatory cytokines as IL-1β, IL-6 and TNF-α, enzymatic activity as GST, GPx, CAT and SOD and neurotransmitter dysfunction (5-HT, serotonin, dopamine and GABA). At the end of the article, based on the literature data, we attempted to present ways to mitigate mycotoxin neurotoxicity using mainly natural substances of plant origin. The data in this review focus on the Fusarium mycotoxins most frequently found in food and will be useful as comparative information for future studies. It is important to conduct further studies to mitigate the neurotoxic effects of Fusarium mycotoxins in order to reduce the development of diseases of the nervous system.

Associations between dietary mycotoxins exposures and risk of hepatocellular carcinoma in a European cohort

Mycotoxins have been hypothesized to contribute to a diversity of adverse health effects in humans, even at low concentrations. Certain mycotoxins are established human carcinogens, whereas for others research suggests potential carcinogenic effects. The aim of this study was to determine the association between dietary exposure to mycotoxins and hepatobiliary cancers in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. EPIC questionnaire data were matched to mycotoxin food occurrence data compiled by the European Food Safety Authority to assess long-term dietary mycotoxin exposure (expressed as μg/kg body weight/day) and then relate them to the risk of hepatocellular carcinoma (HCC) (n = 255) and biliary tract cancers (n = 273). Analyses were conducted using multivariable Cox proportional hazards regression models to compute hazard ratios (HR) and 95% confidence intervals (95% CI). Key food groups contributing to mycotoxin exposure were cereals and cereal-based products, vegetables, non-alcoholic beverages (including fruit juices) and fruits. Estimated intake of deoxynivalenol (DON) and its derivatives was positively associated with HCC risk (HRT3vsT1: 1.90, 95% CI: 1.18-3.05, p-trend <0.01). No statistically significant associations were found for the other mycotoxins. Further research to confirm our observations and investigate potential underlying mechanisms of these compounds is warranted. These data may provide evidence of HCC risks associated with higher dietary intake levels of DON, which has not yet been classified as a human carcinogen.

Inhibitor of Chromosome Segregation in Pseudomonas aeruginosa from Fungal Extracts

Chromosome segregation is an essential cellular process that has the potential to yield numerous targets for drug development. This pathway is presently underutilized partially due to the difficulties in the development of robust reporter assays suitable for high throughput screening. In bacteria, chromosome segregation is mediated by two partially redundant systems, condensins and ParABS. Based on the synthetic lethality of the two systems, we developed an assay suitable for screening and then screened a library of fungal extracts for potential inhibitors of the ParABS pathway, as judged by their enhanced activity on condensin-deficient cells. We found such activity in extracts of Humicola sp. Fractionation of the extract led to the discovery of four new analogues of sterigmatocystin, one of which, 4-hydroxy-sterigmatocystin (4HS), displayed antibacterial activity. 4HS induced the phenotype typical for parAB mutants including defects in chromosome segregation and cell division. Specifically, bacteria exposed to 4HS produced anucleate cells and were impaired in the assembly of the FtsZ ring. Moreover, 4HS binds to purified ParB in a ParS-modulated manner and inhibits its ParS-dependent CTPase activity. The data describe a small molecule inhibitor of ParB and expand the known spectrum of activities of sterigmatocystin to include bacterial chromosome segregation.

Risk assessment of exposure to 12 kinds of mycotoxins through consumption of Pericarpium Citri Reticulatae collected from Three Gorges Reservoir area of China

A method for simultaneous determination of 12 mycotoxins in Pericarpium Citri Reticulataeby HPLC-MS/MS was established to analyze the residues of mycotoxins, inwhich from Three Gorges Reservoir area of China, including AFB1, AFB2, AFG1, AFG2, T-2, FB1, FB2, FB3, ZEN, OTA, OTB and DON.In addition, a probabilistic assessment model based on Monte Carlo simulation method was established in combination with pollution data, and the health risk assessment was carried out by the exposure limit method (MOE).The results showed that the method with strong specificity, good linearity and accurate recovery was established and could be used for the determination of 12 mycotoxins in Pericarpium Citri Reticulatae.In general, the total pollution rate of different degrees of pollution in the 36 batches of Pericarpium Citri Reticulatae sampleswas 75 %. It should be noted thatthe proportion of positive samplescontaminated by one toxin was the highest (59.26 %), and the detection rate of FB3 in Pericarpium Citri Reticulataewas the highest (66.67%), followed by AFG1 (44.44 %), indicating that the medicinal material polluted by AFG1 and AFB3 alone or simultaneously was more serious. Specifically, the detection rate of mycotoxins in Chongqing was the highest (92.31%) on account of the high temperature and humidity in Chongqing, followed by Southeast of Sichuan (83.33%) and West of Hubei (45.45%).On the other hand, the MOE of AFB1 and AFB2 calculated were both greater than 10000, indicating that the health risk of AFB1 and AFB2 exposure caused by taking Pericarpium Citri Reticulatae was low, but the risk of high intake population was higher than that of conventional intake population, which needed to be paid attention to. This study can provide a reference for the safety assessment of clinical medication of Pericarpium Citri Reticulatae inThree Gorges Reservoir area.

Evaluating the human neurotoxicity and toxicological interactions impact of co-occurring regulated and emerging mycotoxins

Mycotoxins can inflict harmful effects on diverse organs, and mounting evidence indicates their potential involvement in human neurodegenerative diseases. Given the common occurrence of these toxins in food, there is an increasing demand for a comprehensive assessment of their combined toxicity to enhance our understanding of their potential hazards. This research investigates mycotoxin exposure from widely consumed cereal-based products, including enniatin B (ENNB), sterigmatocystin (STG), aflatoxin B1 (AFB1), cyclopiazonic acid (CPZ), citrinin (CIT), and ochratoxin A (OTA). Employing the median-effect equation based on Chou and Talalay's mass-action law, we assessed their cytotoxicity in human SH-SY5Y neuronal cells. Notably, ENNB displayed the highest neurotoxicity (IC50 = 3.72 µM), followed by OTA (9.10 µM) and STG (9.99 µM). The combination of OTA + STG exhibited the highest toxicity (IC50 = 3.77 µM), while CPZ + CIT showed the least detrimental effect. Approximately 70 % of tested binary combinations displayed synergistic or additive effects, except for ENNB + STG, ENNB + AFB1, and CPZ + CIT, which showed antagonistic interactions. Intriguingly, the senary combination displayed moderate antagonism at the lowest exposure and moderate synergism at higher doses. OTA exhibited predominantly synergistic interactions, comprising approximately 90 %, a noteworthy finding considering its prevalence in food. Conversely, ENNB interactions tended to be antagonistic. The most remarkable synergy occurred in the STG and CIT combination, enabling a 50-fold reduction in CIT dosage for an equivalent toxic effect. These findings highlight the biological relevance of robust synergistic interactions, emphasizing the need to assess human exposure hazards accurately, particularly considering frequent mycotoxin co-occurrence in environmental and food settings.

Climate Change and Mycotoxins Trends in Serbia and Croatia: A 15-Year Review

This review examines the 15-year presence of mycotoxins in food from Serbia and Croatia to provide a comprehensive overview of trends. Encompassing the timeframe from 2009 to 2023, this study integrates data from both countries and investigates climate change patterns. The results from Serbia focus primarily on maize and milk and show a strong dependence of contamination on weather conditions. However, there is limited data on mycotoxins in cereals other than maize, as well as in other food categories. Conversely, Croatia has a broader spectrum of studies, with significant attention given to milk and maize, along with more research on other cereals, meat, and meat products compared to Serbia. Over the investigated 15-year period, both Serbia and Croatia have experienced notable shifts in climate, including fluctuations in temperature, precipitation, and humidity levels. These changes have significantly influenced agriculture, consequently affecting the occurrence of mycotoxins in various food products. The results summarized in this 15-year review indicate the urgent need for further research and action to address mycotoxins contamination in Serbian and Croatian food supply chains. This urgency is further emphasized by the changing climatic conditions and their potential to exacerbate public health and food safety risks associated with mycotoxins.

In Vitro Digestion and Intestinal Absorption of Mycotoxins Due to Exposure from Breakfast Cereals: Implications for Children's Health

Breakfast cereals play a crucial role in children's diets, providing essential nutrients that are vital for their growth and development. Children are known to be more susceptible than adults to the harmful effects of food contaminants, with mycotoxins being a common concern in cereals. This study specifically investigated aflatoxin B1 (AFB1), enniatin B (ENNB), and sterigmatocystin (STG), three well-characterized mycotoxins found in cereals. The research aimed to address existing knowledge gaps by comprehensively evaluating the bioaccessibility and intestinal absorption of these three mycotoxins, both individually and in combination, when consumed with breakfast cereals and milk. The in vitro gastrointestinal method revealed patterns in the bioaccessibility of AFB1, ENNB, and STG. Overall, bioaccessibility increased as the food progressed from the stomach to the intestinal compartment, with the exception of ENNB, whose behavior differed depending on the type of milk. The ranking of overall bioaccessibility in different matrices was as follows: digested cereal > cereal with semi-skimmed milk > cereal with lactose-free milk > cereal with soy beverage. Bioaccessibility percentages varied considerably, ranging from 3.1% to 86.2% for AFB1, 1.5% to 59.3% for STG, and 0.6% to 98.2% for ENNB. Overall, the inclusion of milk in the ingested mixture had a greater impact on bioaccessibility compared to consuming the mycotoxins as a single compound or in combination. During intestinal transport, ENNB and STG exhibited the highest absorption rates when ingested together. This study highlights the importance of investigating the combined ingestion and transport of these mycotoxins to comprehensively assess their absorption and potential toxicity in humans, considering their frequent co-occurrence and the possibility of simultaneous exposure.

Coordination of two regulators SscA and VosA in Aspergillus nidulans conidia

Airborne fungal spores are a major cause of fungal diseases in humans, animals, and plants as well as contamination of foods. Previous studies found a variety of regulators including VosA, VelB, WetA, and SscA for sporogenesis and the long-term viability in Aspergillus nidulans. To gain a mechanistic understanding of the complex regulatory mechanisms in asexual spores, here, we focused on the relationship between VosA and SscA using comparative transcriptomic analysis and phenotypic studies. The ΔsscA ΔvosA double-mutant conidia have lower spore viability and stress tolerance compared to the ΔsscA or ΔvosA single mutant conidia. Deletion of sscA or vosA affects chitin levels and mRNA levels of chitin biosynthetic genes in conidia. In addition, SscA and VosA are required for the dormant state of conidia and conidial germination by modulating the mRNA levels of the cytoskeleton and development-associated genes. Overall, these results suggest that SscA and VosA play interdependent roles in governing spore maturation, dormancy, and germination in A. nidulans.

Transcriptomic and Proteomic Insights into the Effect of Sterigmatocystin on Aspergillus flavus

Aspergillus flavus is an important fungus that produces aflatoxins, among which aflatoxin B1 (AFB1) is the most toxic and contaminates food and poses a high risk to human health. AFB1 interacts with another mycotoxin sterigmatocystin (STC), which is also a precursor of AFB1. Herein, we determined the effect of STC on AFB1 by evaluating A. flavus transcriptomic and proteomic profiles in the presence or absence of STC by RNA-seq and isobaric tagging, respectively. Overall, 3377 differentially expressed genes were identified by RNA-seq. These genes were mainly associated with the cellular component organisation and biosynthesis, the synthesis of valine, leucine, and isoleucine, and the synthesis of aflatoxin. Clustered genes responsible for AFB1 biosynthesis exhibited varying degrees of downregulation, and norB expression was completely suppressed in the experimental group. During proteomic analysis, 331 genes were differentially expressed in response to STC. These differentially expressed proteins were associated with cell parts and catalytic and antioxidant activities. Differentially expressed proteins predominantly participated in metabolic pathways associated with aflatoxin biosynthesis, glycolysis/gluconeogenesis, glutathione metabolism, and carbon metabolism. Notably, the upregulated and downregulated enzymes in carbohydrate and glutathione metabolisms may serve as potential gateways for inhibiting aflatoxin biosynthesis. Moreover, twelve proteins including seven downregulated ones involved in aflatoxin biosynthesis were identified; among them, AflG was the most downregulated, suggesting that it may be the key enzyme responsible for inhibiting aflatoxin synthesis. These findings provide novel insights into A. flavus control and the mechanisms regulating mycotoxin production.

Regional distribution and diversity of Aspergillus and Penicillium species on Croatian traditional meat products

Various factors, such as weather and production practices (e.g., environmental hygiene, process duration, raw material quality, ripening temperature, and relative humidity), in combination with the intrinsic product properties (e.g., pH, aw, salt content), significantly affect the growth of surface moulds. The aim of this study was to isolate and identify surface moulds retrieved from traditional meat products (TMPs) and correlate these data to the production region and production technology. The surface of 250 TMPs (dry-fermented sausages, n = 108; dry-cured meat products, n = 142) from five Croatian regions were sampled during a two-year period. Dry-fermented sausages had a significantly higher pH and a lower salt concentration when compared to dry-cured meat products. In total, 528 isolates were obtained, comprising 20 Penicillium and 17 Aspergillus species. The species most frequently isolated from the dry-fermented sausages were P. commune (32.4 %), A. proliferans (33 %), and P. solitum (14.8 %), while A. proliferans (52.1 %), P. commune (28.9 %) and P. citrinum (19.7 %) predominated in dry-cured meat products. Aspergillus predominated on the TMPs from southern Croatia, while Penicillium was prevalent on products from the other four regions, possibly due to differences in weather conditions. Seven potentially mycotoxigenic species (A. creber, A. flavus, A. niger, A. westerdijkiae, P. citrinum, P. commune, and P. nordicum) were isolated and identified. Regular monitoring of mould species and their toxigenic metabolites present on traditional meat products is of the utmost importance from the public health perspective, while the results of such a monitoring can prove beneficial for the tailoring of the production technology development.

Fungal and Toxin Contaminants in Cereal Grains and Flours: Systematic Review and Meta-Analysis

Cereal grains serve as the cornerstone of global nutrition, providing a significant portion of humanity's caloric requirements. However, the presence of fungal genera, such Fusarium, Penicillium, Aspergillus, and Alternaria, known for their mycotoxin-producing abilities, presents a significant threat to human health due to the adverse effects of these toxins. The primary objective of this study was to identify the predominant fungal contaminants in cereal grains utilized in breadmaking, as well as in flour and bread. Moreover, a systematic review, including meta-analysis, was conducted on the occurrence and levels of mycotoxins in wheat flour from the years 2013 to 2023. The genera most frequently reported were Fusarium, followed by Penicillium, Aspergillus, and Alternaria. Among the published reports, the majority focused on the analysis of Deoxynivalenol (DON), which garnered twice as many reports compared to those focusing on Aflatoxins, Zearalenone, and Ochratoxin A. The concentration of these toxins, in most cases determined by HPLC-MS/MS or HPLC coupled with a fluorescence detector (FLD), was occasionally observed to exceed the maximum limits established by national and/or international authorities. The prevalence of mycotoxins in flour samples from the European Union (EU) and China, as well as in foods intended for infants, exhibited a significant reduction compared to other commercial flours assessed by a meta-analysis investigation.

Traditional Meat Products-A Mycotoxicological Review

Traditional meat products are commonly produced in small family businesses. However, big industries are also involved in the production of this kind of product, especially since a growing number of consumers crave the traditional taste and aromas. The popularization of original and organic products has resulted in a return to traditional production methods. Traditional meat products are produced worldwide. However, in such (domesticated) conditions there is a potential danger for mycotoxin contamination. This review aims to present the sources of mycotoxins in traditional meat products, the most common mycotoxins related to such meat products, and future prospects regarding the suppression of their occurrence. Special attention should be paid to reducing the transfer of mycotoxins via the food chain from animal feed to animals to humans (stable-to-table principle), which is also described in this review. Other sources of mycotoxins (spices, environment, etc.) should also be monitored for mycotoxins in traditional production. The importance of monitoring and regulating mycotoxins in meat products, especially in traditional meat products, is slowly being recognized by the institutions and hopefully, in the future, can deliver legally regulated limits for such products. This is especially important since meat products are available to the general population and can seriously affect human health.

Co-occurrence of mycotoxins and other fungal metabolites in total mixed rations of cows from dairy farms in Punjab, Pakistan

After India and the USA, Pakistan is the third country leading in global dairy production, a sector of very high socioeconomic relevance in Asia. Mycotoxins can affect animal health, reproduction and productivity. This study analysed a broad range of co-occurring mycotoxins and fungal secondary metabolites derived from Alternaria, Aspergillus, Fusarium, Penicillium and other fungal species. To complete this, a validated multi-metabolite liquid chromatography/electrospray ionization-tandem mass spectrometric (LC/ESI-MS/MS) method was employed, detecting 96 of > 500 tested secondary fungal metabolites. This first preliminary study demonstrated that total mixed rations (TMRs) (n = 30) from big commercial dairy cattle farms (> 200 lactating cows) in Punjab, Pakistan, presented ubiquitous contamination with mixtures of mycotoxins. The mean of mycotoxins per sample was 14, ranging from 11 to 20 mycotoxins among all TMR samples. Metabolites derived from other fungi and Fusarium spp. showed the highest levels, frequency and diversity among the detected fungal compounds. Among the most prevalent mycotoxins were Fusarium toxins like fumonisins B1 (FB1) (93%), B2 (FB2) (100%) and B3 (FB3) (77%) and others. Aflatoxin B1 (AFB1) was evidenced in 40% of the samples, and 7% exceeded the EU maximum limit for feeding dairy cattle (5 µg/kg at 88% dry matter). No other mycotoxin exceeds the EU guidance values (GVs). Additionally, we found that dietary ingredients like corn grain, soybean meal and canola meal were related to increased contamination of some mycotoxins (like FB1, FB2 and FB3) in TMR from the province of Punjab, Pakistan. Among typical forage sources, the content of maize silage was ubiquitous. Individually, the detected mycotoxins represented relatively low levels. However, under a realistic scenario, long-term exposure to multiple mycotoxins and other fungal secondary metabolites can exert unpredictable effects on animal health, reproduction and productivity. Except for ergot alkaloids (73%), all the groups of metabolites (i.e. derived from Alternaria spp., Aspergillus spp., Fusarium spp., Penicillium spp. and other fungi) occurred in 100% of the TMR samples. At individual levels, no other mycotoxins than AFB1 represented a considerable risk; however, the high levels of co-occurrence with several mycotoxins/metabolites suggest that long-term exposure should be considered because of their potential toxicological interactions (additive or synergistic effects).

The Occurrence of Non-Regulated Mycotoxins in Foods: A Systematic Review

The aim of this systematic review is to provide an update on the occurrence and co-occurrence of selected non-regulated mycotoxins and provide an overview of current regulations. Fifteen non-regulated mycotoxins were found in 19 food categories worldwide. On top of that, 38 different combinations of non-regulated mycotoxins were found, with mixtures varying from binary combinations up to 12 mycotoxins. Taking into consideration the amount of evidence regarding the prevalence and co-occurrence of non-regulated mycotoxins, future steps should be taken considering continuous monitoring, scientific exchange, and generation of high-quality data. To enhance data quality, guidelines outlining the minimum quality criteria for both occurrence data and metadata are needed. By doing so, we can effectively address concerns related to the toxicity of non-regulated mycotoxins. Furthermore, obtaining more data concerning the co-occurrence of both regulated and non-regulated mycotoxins could aid in supporting multiple chemical risk assessment methodologies. Implementing these steps could bolster food safety measures, promote evidence-based regulations, and ultimately safeguard public health from the potential adverse effects of non-regulated mycotoxins.

In Vivo Genotoxicity and Toxicity Assessment of Sterigmatocystin Individually and in Mixture with Aflatoxin B1

Mycotoxins are natural food and feed contaminants produced by several molds. The primary mode of exposure in humans and animals is through mixtures. Aflatoxin B1 (AFB1) and sterigmatocystin (STER) are structurally related mycotoxins that share the same biosynthetic route. Few in vivo genotoxicity assays have been performed with STER. In the present genotoxicity study, Wistar rats were dosed orally with STER (20 mg/kg b.w.), AFB1 (0.25 mg/kg b.w.) or a mixture of both in an integrated micronucleus (bone marrow) and comet study (liver and kidney). STER was dosed at the highest feasible dose in corn oil. No increase in the percentage of micronuclei in bone marrow was observed at any condition. Slight DNA damage was detected in the livers of animals treated with AFB1 or the mixture (DNA strand breaks and Fpg (Formamidopyrimidine DNA glycosylase)-sensitive sites, respectively). Plasma, liver, and kidney samples were analyzed with LC-MS/MS demonstrating exposure to both mycotoxins. General toxicity parameters (organs absolute weight, biochemistry, and histopathology) were not altered either individually or in the mixture. The overall absence of individual genotoxicity did not allow us to set any type of interaction in the mixture. However, a possible toxicokinetic interaction was observed.

Study of co-occurrence of mycotoxins in cocoa beans in Brazil by liquid chromatography-tandem mass spectrometry (LC-MS/MS)

In this study, 135 samples of cocoa beans collected in the Amazon and Atlantic Forest regions of Brazil were analysed to evaluate the possible co-occurrence of 34 mycotoxins. The results indicate that 42% of the cocoa samples exhibited quantifiable levels for 11 mycotoxins: aflatoxins (AFs) B1, B2 and G1; ochratoxin A; citrinin; cyclopiazonic acid; tenuazonic acid; paxilline; sterigmatocystin; zearalenone and fumonisin B2. Of the samples, 18% exhibited the co-occurrence of up to six mycotoxins. No toxins belonging to the groups of trichothecenes or ergot alkaloids were detected. Contingency analysis of the incidence of mycotoxins did not show significant differences between the two regions evaluated. Seven samples were contaminated with AFs, while only one contained ochratoxin A above 10 μg kg-1. The accuracy of the method was evaluated by proficiency testing for ochratoxin A, where satisfactory Z-scores were obtained.

Biomonitoring of 19 Mycotoxins in Plasma from Food-Producing Animals (Cattle, Poultry, Pigs, and Sheep)

Mycotoxins are of great concern in relation to food safety. When animals are exposed to them, health problems, economic losses in farms and related industries, and the carryover of these compounds to animal-derived foods can occur. Therefore, control of animal exposure is of great importance. This control may be carried out by analyzing raw material and/or feed or through the analysis of biomarkers of exposure in biological matrixes. This second approach has been chosen in the present study. Firstly, a methodology capable of analyzing mycotoxins and some derivatives (AFB1, OTA, ZEA, DON, 3- and 15-ADON, DOM-1, T-2, HT-2, AFM1, STER, NEO, DAS, FUS-X, AFB2, AFG1, AFG2, OTB, and NIV) by LC-MS/MS in human plasma, has been revalidated to be applied in animal plasma. Secondly, this methodology was used in 80 plasma samples obtained from animals dedicated to food production: cattle, pigs, poultry, and sheep (20 samples of each), with and without being treated with a mixture of β-glucuronidase-arylsulfatase to determine possible glucuronide and sulfate conjugates. Without enzymatic treatment, no mycotoxin was detected in any of the samples. Only one sample from poultry presented levels of DON and 3- and 15-ADON. With enzymatic treatment, only DON (1 sample) and STER were detected. The prevalence of STER was 100% of the samples, without significant differences among the four species; however, the prevalence and levels of this mycotoxin in the previously analyzed feed were low. This could be explained by the contamination of the farm environment. Animal biomonitoring can be a useful tool to assess animal exposure to mycotoxins. However, for these studies to be carried out and to be useful, knowledge must be increased on appropriate biomarkers for each mycotoxin in different animal species. In addition, adequate and validated analytical methods are needed, as well as knowledge of the relationships between the levels found in biological matrices and mycotoxin intake and toxicity.

Mixtures of Mycotoxins, Phytoestrogens, and Other Secondary Metabolites in Whole-Plant Corn Silages and Total Mixed Rations of Dairy Farms in Central and Northern Mexico

Mycotoxins and endocrine disruptors such as phytoestrogens can affect cattle health, reproduction, and productivity. Most studies of mycotoxins in dairy feeds in Mexico and worldwide have been focused on a few (regulated) mycotoxins. In contrast, less known fungal toxins, phytoestrogens, and other metabolites have been neglected and underestimated. This study analyzed a broad spectrum (>800) of mycotoxins, phytoestrogens, and fungal, plant, and unspecific secondary metabolites in whole-plant corn silages (WPCSs) and total mixed rations (TMRs) collected from 19 Mexican dairy farms. A validated multi-metabolite liquid chromatography/electrospray ionization-tandem mass spectrometric (LC/ESI-MS/MS) method was used. Our results revealed 125 of >800 tested (potentially toxic) secondary metabolites. WPCSs/TMRs in Mexico presented ubiquitous contamination with mycotoxins, phytoestrogens, and other metabolites. The average number of mycotoxins per TMR was 24, ranging from 9 to 31. Fusarium-derived secondary metabolites showed the highest frequencies, concentrations, and diversity among the detected fungal compounds. The most frequently detected mycotoxins in TMRs were zearalenone (ZEN) (100%), fumonisin B1 (FB1) (84%), and deoxynivalenol (84%). Aflatoxin B1 (AFB1) and ochratoxin A (OTA), previously reported in Mexico, were not detected. All TMR samples tested positive for phytoestrogens. Among the investigated dietary ingredients, corn stover, sorghum silage, and concentrate proportions were the most correlated with levels of total mycotoxins, fumonisins (Fs), and ergot alkaloids, respectively.

Photoluminescent Gold/BSA Nanoclusters (AuNC@BSA) as Sensors for Red-Fluorescence Detection of Mycotoxins

The BSA-encapsulated gold nanoclusters (AuNC@BSA) have drawn considerable interest and demonstrated applications as biological sensors. In this study, we demonstrated that the red-emitting AuNC@BSA prepared using a modified procedure fully retained the binding of standard BSA-ligands (small molecule drugs), significantly improving fluorescence detection in some cases due to the red-emission property. Further, we showed that AuNC@BSA efficiently bind a series of aflatoxin-related mycotoxins as well as the aliphatic mycotoxin FB1, reporting interactions in the nanomolar range by instantaneous emission change at 680 nm. Such red emission detection is advantageous over current detection strategies for the same mycotoxins, based on complex mass spectrometry procedures or, eventually (upon chemical modification of the mycotoxin), by fluorescence detection in the UV range (<400 nm). The later technique yields fluorescence strongly overlapping with the intrinsic absorption and emission of biorelevant mixtures in which mycotoxins appear. Thus, here we present a new approach using the AuNC@BSA red fluorescence reporter for mycotoxins as a fast, cheap, and simple detection technique that offers significant advantages over currently available methods.

Mycotoxins and Essential Oils-From a Meat Industry Hazard to a Possible Solution: A Brief Review

The preservation of food supplies has been humankind's priority since ancient times, and it is arguably more relevant today than ever before. Food sustainability and safety have been heavily prioritized by consumers, producers, and government entities alike. In this regard, filamentous fungi have always been a health hazard due to their contamination of the food substrate with mycotoxins. Additionally, mycotoxins are proven resilient to technological processing. This study aims to identify the main mycotoxins that may occur in the meat and meat products "Farm to Fork" chain, along with their effect on the consumers' health, and also to identify effective methods of prevention through the use of essential oils (EO). At the same time, the antifungal and antimycotoxigenic potential of essential oils was considered in order to provide an overview of the subject. Targeting the main ways of meat products' contamination, the use of essential oils with proven in vitro or in situ efficacy against certain fungal species can be an effective alternative if all the associated challenges are addressed (e.g., application methods, suitability for certain products, toxicity).

Mycotoxin Exposure and Renal Cell Carcinoma Risk: An Association Study in the EPIC European Cohort

BACKGROUND

Mycotoxins have been suggested to contribute to a spectrum of adverse health effects in humans, including at low concentrations. The recognition of these food contaminants being carcinogenic, as co-occurring rather than as singularly present, has emerged from recent research. The aim of this study was to assess the potential associations of single and multiple mycotoxin exposures with renal cell carcinoma risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.

METHODS

Food questionnaire data from the EPIC cohort were matched to mycotoxin food occurrence data compiled by the European Food Safety Authority (EFSA) from European Member States to assess long-term dietary mycotoxin exposures, and to associate these with the risk of renal cell carcinoma (RCC, n = 911 cases) in 450,112 EPIC participants. Potential confounding factors were taken into account. Analyses were conducted using Cox's proportional hazards regression models to compute hazard ratios (HRs) and 95% confidence intervals (95% CIs) with mycotoxin exposures expressed as µg/kg body weight/day.

RESULTS

Demographic characteristics differed between the RCC cases and non-cases for body mass index, age, alcohol intake at recruitment, and other dietary factors. In addition, the mycotoxin exposure distributions showed that a large proportion of the EPIC population was exposed to some of the main mycotoxins present in European foods such as deoxynivalenol (DON) and derivatives, fumonisins, Fusarium toxins, Alternaria toxins, and total mycotoxins. Nevertheless, no statistically significant associations were observed between the studied mycotoxins and mycotoxin groups, and the risk of RCC development.

CONCLUSIONS

These results show an absence of statistically significant associations between long-term dietary mycotoxin exposures and RCC risk. However, these results need to be validated in other cohorts and preferably using repeated dietary exposure measurements. In addition, more occurrence data of, e.g., citrinin and fumonisins in different food commodities and countries in the EFSA database are a prerequisite to establish a greater degree of certainty.

First report on the metabolic characterization of Sterigmatocystin production by select Aspergillus species from the Nidulantes section in Foeniculum vulgare

Spices are typically grown in climates that support the growth of toxigenic fungi and the production of mycotoxins. The Aspergilli described in this study, as well as the sterigmatocystin (STC) detected, are causes for concern due to their potential to induce food poisoning. One of the most well-known producers of the carcinogenic STC is Aspergillus nidulans. This research explores the occurrence of STC-producing fungi in Foeniculum vulgare, a spice that is marketed in India and other parts of the world. This innovative study details the mycotoxigenic potential of five Aspergilli belonging to Section Nidulantes, namely Aspergillus latus (02 isolates), Emericella quadrilineata (02 isolates), and Aspergillus nidulans (01 isolate), with respect to STC contamination. These five isolates of Aspergilli were screened to produce STC on yeast extract sucrose (YES) medium in a controlled environment with regard to light, temperature, pH, and humidity, among other variables. The expression patterns of regulatory genes, namely, aflR, laeA, pacC, fluG, flbA, pksA, and mtfA were studied on the Czapek–Dox agar (CDA) medium. STC biosynthesis by the test isolates was done in potato dextrose broth (PDB) under optimum conditions, followed by the extraction and purification of the broth using ethyl acetate. High-performance liquid chromatography (HPLC) with an ultraviolet (UV) detector was utilized to detect compounds in eluted samples. F. vulgare contains Aspergilli that have been shown to have mycotoxigenic potential, which can accumulate in the spice during its active growth and thereby cause the elaboration of mycotoxins.

Interaction of the Emerging Mycotoxins Beauvericin, Cyclopiazonic Acid, and Sterigmatocystin with Human Serum Albumin

Beauvericin (BEA), cyclopiazonic acid (CPA), and sterigmatocystin (STC) are emerging mycotoxins. They appear as contaminants in food and animal feed, leading to economic losses and health risks. Human serum albumin (HSA) forms stable complexes with certain mycotoxins, including ochratoxins, alternariol, citrinin, and zearalenone. HSA binding can influence the toxicokinetics of xenobiotics, and albumin can also be considered and applied as a relatively cheap affinity protein. Therefore, we examined the potential interactions of BEA, CPA, and STC with HSA employing fluorescence spectroscopy, ultracentrifugation, ultrafiltration, and molecular modeling. Spectroscopic and ultracentrifugation studies demonstrated the formation of low-affinity BEA–HSA (K_a ≈ 10³ L/mol) and moderately strong CPA–HSA and STC–HSA complexes (K_a ≈ 10⁴ L/mol). In ultrafiltration experiments, CPA slightly displaced each site marker (warfarin, naproxen, and camptothecin) tested, while BEA and STC did not affect significantly the albumin binding of these drugs. Modeling studies suggest that CPA occupies Sudlow’s site I, while STC binds to the Heme site (FA1) on HSA. Considering the interactions of CPA with the site markers, the CPA–HSA interaction may have toxicological importance.

Analysis of mold and mycotoxins in naturally infested indoor building materials

Health issues of residents of mold-infested housing are reported on a regular basis, and reasons for the arising impairments can be manifold. One possible cause are the toxic secondary metabolite produced by indoor microfungi (mycotoxins). To enable a more thorough characterization of the exposure to mycotoxins in indoor environments, data on occurrence and quantities of mycotoxins is essential. In the presented study, 51 naturally mold-infested building material samples were analyzed applying a previously developed method based on ultra-high performance liquid chromatography (UHPLC) separation in combination with triple-quadrupole mass spectrometry (TQMS) detection. A total of 38 secondary metabolites derived from different indoor mold genera like Aspergillus, Fusarium, Penicillium, and Stachybotrys were analyzed, of which 16 were detectable in 28 samples. As both the spectrum of target analytes and the investigated sample matrices showed high chemical varieties, an alternative calibration approach was applied complementary to identify potentially emerging matrix effects during ionization and mass spectrometric detection. Overall, strong alterations of analyte signals were rare, and compensation of considerable matrix suppression/enhancement only had to be performed for certain samples. Besides mycotoxin determination and quantification, the presence of 18 different mold species was confirmed applying microbiological approaches in combination with macro- and microscopic identification according to DIN ISO 16000-17:2010-06. These results additionally highlight the diversity of mycotoxins potentially arising in indoor environments and leads to the assumption that indoor mycotoxin exposure stays an emerging topic of research, which has only just commenced.

Cocktails of Mycotoxins, Phytoestrogens, and Other Secondary Metabolites in Diets of Dairy Cows in Austria: Inferences from Diet Composition and Geo-Climatic Factors

Dairy production is a pivotal economic sector of Austrian and European agriculture. Dietary toxins and endocrine disruptors of natural origin such as mycotoxins and phytoestrogens can affect animal health, reproduction, and productivity. This study characterized the profile of a wide spectrum of fungal, plant, and unspecific secondary metabolites, including regulated, emerging, and modified mycotoxins, phytoestrogens, and cyanogenic glucosides, in complete diets of lactating cows from 100 Austrian dairy farms. To achieve this, a validated multi-metabolite liquid chromatography/electrospray ionization−tandem mass spectrometric (LC/ESI−MS/MS) method was employed, detecting 155 of >800 tested metabolites. Additionally, the most influential dietary and geo-climatic factors related to the dietary mycotoxin contamination of Austrian dairy cattle were recognized. We evidenced that the diets of Austrian dairy cows presented ubiquitous contamination with mixtures of mycotoxins and phytoestrogens. Metabolites derived from Fusarium spp. presented the highest concentrations, were the most recurrent, and had the highest diversity among the detected fungal compounds. Zearalenone, deoxynivalenol, and fumonisin B1 were the most frequently occurring mycotoxins considered in the EU legislation, with detection frequencies >70%. Among the investigated dietary factors, inclusion of maize silage (MS) and straw in the diets was the most influential factor in contamination with Fusarium-derived and other fungal toxins and metabolites, and temperature was the most influential among the geo-climatic factors.

The Occurrence of Five Unregulated Mycotoxins Most Important for Traditional Dry-Cured Meat Products

This study investigated the occurrence of 5 unregulated mycotoxins in a total of 250 traditional dry-cured meat products sampled in 2020 and 2021 in five Croatian regions (eastern, northern, central, western, and southern). Aflatoxin B₁ (AFB₁), ochratoxin A (OTA), sterigmatocystin (STC), citrinin (CIT), and cyclopiazonic acid (CPA) concentrations were related to the geographical region of the product’s origin and to local weather. The results revealed the contamination of 27% of samples, namely, STC in 4% of samples in concentrations of up to 3.93 µg/kg, OTA in 10% of samples in concentrations of up to 4.81 µg/kg, and CPA in 13% of samples in concentrations of up to 335.5 µg/kg. No AFB₁ or CIT contamination was seen. Although no statistically significant differences in concentrations of individual mycotoxins across the production regions were found, differences in mycotoxin occurrence were revealed. The eastern and western regions, with moderate climate, delivered the largest number of contaminated samples, while the southern region, often compared with subtropics, delivered the smallest, so that the determined mycotoxins were probably mainly produced by the Penicillium rather than the Aspergillus species. Due to the interaction of various factors that may affect mycotoxin biosynthesis during production, the detected concentrations cannot be related solely to the weather.

Metabolism of versicolorin A, a genotoxic precursor of aflatoxin B1: Characterization of metabolites using in vitro production of standards

The toxicity of mycotoxins containing bisfuranoid structures such as aflatoxin B1 (AFB1) depends largely on biotransformation processes. While the genotoxicity and mutagenicity of several bisfuranoid mycotoxins including AFB1 and sterigmatocystin have been linked to in vivo bioactivation of these molecules into reactive epoxide forms, the metabolites of genotoxic and mutagenic AFB1 precursor versicolorin A (VerA) have not yet been characterized. Because this molecule is not available commercially, our strategy was to produce a library of metabolites derived from the biotransformation of in-house purified VerA, following incubation with human liver S9 fractions, in presence of appropriate cofactors. The resulting chromatographic and mass-spectrometric data were used to identify VerA metabolites produced by intestinal cell lines as well as intestinal and liver tissues exposed ex vivo. In this way, we obtained a panel of metabolites suggesting the involvement of phase I (M + O) and phase II (glucuronide and sulfate metabolites) enzymes, the latter of which is implicated in the detoxification process. This first qualitative description of the metabolization products of VerA suggests bioactivation of the molecule into an epoxide form and provides qualitative analytic data to further conduct a precise metabolism study of VerA required for the risk assessment of this emerging mycotoxin.

Overview of Recent Liquid Chromatography Mass Spectrometry-Based Methods for Natural Toxins Detection in Food Products

Natural toxins include a wide range of toxic metabolites also occurring in food and products, thus representing a risk for consumer health. In the last few decades, several robust and sensitive analytical methods able to determine their occurrence in food have been developed. Liquid chromatography mass spectrometry is the most powerful tool for the simultaneous detection of these toxins due to its advantages in terms of sensitivity and selectivity. A comprehensive review on the most relevant papers on methods based on liquid chromatography mass spectrometry for the analysis of mycotoxins, alkaloids, marine toxins, glycoalkaloids, cyanogenic glycosides and furocoumarins in food is reported herein. Specifically, a literature search from 2011 to 2021 was carried out, selecting a total of 96 papers. Different approaches to sample preparation, chromatographic separation and detection mode are discussed. Particular attention is given to the analytical performance characteristics obtained in the validation process and the relevant application to real samples.

Combined Exposure to Multiple Mycotoxins: An Example of Using a Tiered Approach in a Mixture Risk Assessment

Humans are exposed to mycotoxins on a regular basis. Exposure to a mixture of mycotoxins may, therefore, result in a combination of adverse effects, or trigger the same effects. This should be accounted for when assessing the combined risk of multiple mycotoxins. Here, we show the outcome of using different approaches in assessing the risks related to the combined exposure to mycotoxins. We performed a tiered approach using assessment groups with a common target organ (kidney, liver and haematologic system), or a common adverse effect (phenomenon) (reduced white blood cell count), to combine the exposure to mycotoxins. The combined exposure was calculated for the individuals in this assessment, using the Monte Carlo Risk Assessment (MCRA) tool. The risk related to this combined exposure was assessed using toxicological reference values, e.g., health based guidance values. We show that estimating the combined risk by adding the single compounds' risk distributions slightly overestimates the combined risk in the 95th percentile, as compared to combining the exposures at an individual level. We also show that relative potency factors can be used to refine the mixture risk assessment, as compared to ratios of toxicological reference values with different effect sizes and assessment factors.

Mycotoxins along the tea supply chain: A dark side of an ancient and high valued aromatic beverage

ABSTRACTSTea (Camellia sinensis L.) is a high valued beverage worldwide since ancient times; more than three billion cups of tea are consumed each day. Leaf extracts of the plant are used for food preservation, cosmetics, and medicinal purposes. Nevertheless, tea contaminated with mycotoxins poses a serious health threat to humans. Mycotoxin production by tea fungi is induced by a variety of factors, including poor processing methods and environmental factors such as high temperature and humidity. This review summarizes the studies published to date on mycotoxin prevalence, toxicity, the effects of climate change on mycotoxin production, and the methods used to detect and decontaminate tea mycotoxins. While many investigations in this domain have been carried out on the prevalence of aflatoxins and ochratoxins in black, green, pu-erh, and herbal teas, much less information is available on zearalenone, fumonisins, and Alternaria toxins. Mycotoxins in teas were detected using several methods; the most commonly used being the High-Performance Liquid Chromatography (HPLC) with fluorescence detection, followed by HPLC with tandem mass spectrometry, gas chromatography and enzyme-linked immunosorbent assay. Further, mycotoxins decontamination methods for teas included physical, chemical, and biological methods, with physical methods being most prevalent. Finally, research gaps and future directions have also been discussed.

Profiles of Sterigmatocystin and Its Metabolites during Traditional Chinese Rice Wine Processing

Mycotoxin pollution is widespread in cereal, which greatly threatens food security and human health. In this study, the migration and transformation of sterigmatocystin (STG) mycotoxin during the contaminated rice wine processing was systematically assessed. QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) coupled with ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UPLC−MS/MS) method was firstly established for STG analysis in rice wine. It was found that high levels of rice leaven caused a significant reduction in STG in the fermented rice and wine, which was mainly due to the adsorption of yeast cells and Rhizopus biological degradation. However, compared with rice, the levels of STG in separated fermented wine was significantly decreased by 88.6%, possibly attributed to its high log Kow (3.81) and low water solubility (1.44 mg/L). The metabolites of STG (i.e., monohydroxy STG) were identified in rice wine fermentation for the first time. Moreover, STG disturbed the metabolic profile rice wine composition mainly by glycine, serine and threonine metabolism, alanine, aspartate and glutamate metabolism, purine metabolism pathway, particularly with regard to eight amino acids and sixteen lipids. This study elucidated the STG migration and transformation mechanism during the rice wine processing. The finding provided new analytical method for mycotoxin exposure and pollutant in food production, which may support agricultural production and food security.

Fungal species and mycotoxins in mouldy spots of grass and maize silages in Austria

Fungi and mycotoxins in silage can have detrimental consequences for both cattle and human health. This pilot study identified, via the routinary direct plating method, the dominant cultivable fungi in mouldy grass silages (GS) (n = 19) and maize silages (MS) (n = 28) from Austria. The profiles of regulated, modified, and emerging mycotoxins together with other fungal metabolites were analysed via LC-(ESI)MS/MS. Penicillium roqueforti, Saccharomyces spp., Geotrichum candidum, Aspergillus fumigatus and Monascus ruber were the most frequent fungal organisms identified. Other species including Mucor circinelloides, Fusarium spp. and Paecilomyces niveus were detected at lower frequencies. The presence of complex mixtures of toxic and potentially toxic compounds was evidenced by high levels and occurrences (≥ 50%) of Penicillium-produced compounds such as mycophenolic acid (MPA), roquefortines (ROCs), andrastins (ANDs) and marcfortine A. Mouldy silages contained toxins commonly produced by genus Fusarium (e.g. zearalenone (ZEN) and trichothecenes), Alternaria (like tenuazonic acid (TeA) and alternariol (AHO)) and Aspergillus (such as sterigmatocystin (STC)). Compared to those in GS, mouldy spots in MS presented significantly higher fungal counts and more diverse toxin profiles, in addition to superior levels of Fusarium spp., Penicillium spp. and total fungal metabolites. Generally, no correlation between mould counts and corresponding metabolites was detected, except for the counts of P. roqueforti, which were positively correlated with Penicillium spp. metabolites in mouldy MS. This study represents a first assessment of the fungal diversity in mouldy silage in Austria and highlights its potential role as a substantial contributor to contamination with complex mycotoxin mixtures in cattle diets.

Occurrence and risk assessment of sterigmatocystin in agricultural products and processed foods in Korea

Sterigmatocystin (STC), a carcinogenic mycotoxin, is known to be produced during the biosynthetic pathway of aflatoxin B₁. STC in various foods was determined by LC-MS/MS and its risks were assessed. The analytical method was validated in different food categories, and the performance was acceptable based on the criteria of AOAC. A total 1,135 samples (613 agricultural products and 522 processed foods) were analysed, and STC was detected in 46 samples, indicating a detection rate of 4.1%. STC was found in the range of 0.08-10.07 ng/g, and the detection rates of STC were 3.9% in agricultural products and 4.2% in processed foods. The exposure to STC by average consumption of foods was estimated to 0.09 ng/kg b.w./day. The margin of exposure (MOE) approach was applied to assess the risk of STC, and MOE for the whole population was over 1 × 10⁶. Exposure to STC from the consumption of foods distributed in Korea is unlikely to cause human health problems.

Mycotoxin exposure biomonitoring in breastfed and non-exclusively breastfed Nigerian children

A multi-specimen, multi-mycotoxin approach involving ultra-sensitive LC-MS/MS analysis of breast milk, complementary food and urine was applied to examine mycotoxin co-exposure in 65 infants, aged 1-18 months, in Ogun state, Nigeria. Aflatoxin M₁ was detected in breast milk (4/22 (18%)), while six other classes of mycotoxins were quantified; including dihydrocitrinone (6/22 (27%); range: 14.0-59.7 ng/L) and sterigmatocystin (1/22 (5%); 1.2 ng/L) detected for the first time. Seven distinct classes of mycotoxins including aflatoxins (9/42 (21%); range: 1.0-16.2 µg/kg) and fumonisins (12/42 (29%); range: 7.9-194 µg/kg) contaminated complementary food. Mycotoxins covering seven distinct classes with diverse structures and modes of action were detected in 64/65 (99%) of the urine samples, demonstrating ubiquitous exposure. Two aflatoxin metabolites (AFM₁ and AFQ₁) and FB₁ were detected in 6/65 (9%), 44/65 (68%) and 17/65 (26%) of urine samples, respectively. Mixtures of mycotoxin classes were common, including 22/22 (100%), 14/42 (33%) and 56/65 (86%) samples having 2-6, 2-4, or 2-6 mycotoxins present, for breast milk, complementary food and urine, respectively. Aflatoxin and/or fumonisin was detected in 4/22 (18%), 12/42 (29%) and 46/65 (71%) for breast milk, complimentary foods and urine, respectively. Furthermore, the detection frequency, median concentrations and occurrence of mixtures were typically greater in urine of non-exclusively breastfed compared to exclusively breastfed infants. The study provides novel insights into mycotoxin co-exposures in early-life. Albeit a small sample set, it highlights transition to higher levels of infant mycotoxin exposure as complementary foods are introduced, providing impetus to mitigate during this critical early-life period and encourage breastfeeding.

Urinary Biomarkers of Mycotoxin Induced Nephrotoxicity-Current Status and Expected Future Trends

The intensifying world-wide spread of mycotoxigenic fungal species has increased the possibility of mycotoxin contamination in animal feed and the human food chain. Growing evidence shows the deleterious toxicological effects of mycotoxins from infants to adults, while large population-based screening programs are often missing to identify affected individuals. The kidney functions as the major excretory system, which makes it particularly vulnerable to nephrotoxic injury. However, few studies have attempted to screen for kidney injury biomarkers in large, mycotoxin-exposed populations. As a result, there is an urgent need to screen them with sensitive biomarkers for potential nephrotoxicity. Although a plethora of biomarkers have been tested to estimate the harmful effects of a wide spectrum of toxicants, β₂-microglobulin (β₂-MG) and N-acetyl-β-D-glucosaminidase (NAG) are currently the dominant biomarkers employed routinely in environmental toxicology research. Nevertheless, kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) are also emerging as useful and informative markers to reveal mycotoxin induced nephrotoxicity. In this opinion article we consider the nephrotoxic effects of mycotoxins, the biomarkers available to detect and quantify the kidney injuries caused by them, and to recommend biomarkers to screen mycotoxin-exposed populations for renal damage.

Pathways of Mycotoxin Occurrence in Meat Products: A Review

Documented cases of mycotoxin occurrence in meat products call for further research into potential contamination sources, especially given an ever more increasing consumption of these nutritionally rich products. These foodstuffs can be contaminated with mycotoxins through three pathways: contaminated spices and other raw materials, mycotoxin-producing moulds present on the surface of dry-cured meat products, and carry-over effect from farm animals exposed to contaminated feed. In order to establish meat products’ mycotoxin contamination more precisely, the concentrations of all mycotoxins of relevance for these products should be determined. This manuscript reviews data on major mycotoxins present in different types of meat products, and discusses the contamination pathways, contamination levels and control & preventative measures.

Prioritization of Mycotoxins Based on Their Genotoxic Potential with an In Silico-In Vitro Strategy

Humans are widely exposed to a great variety of mycotoxins and their mixtures. Therefore, it is important to design strategies that allow prioritizing mycotoxins based on their toxic potential in a time and cost-effective manner. A strategy combining in silico tools (Phase 1), including an expert knowledge-based (DEREK Nexus®, Lhasa Limited, Leeds, UK) and a statistical-based platform (VEGA QSAR©, Mario Negri Institute, Milan, Italy), followed by the in vitro SOS/umu test (Phase 2), was applied to a set of 12 mycotoxins clustered according to their structure into three groups. Phase 1 allowed us to clearly classify group 1 (aflatoxin and sterigmatocystin) as mutagenic and group 3 (ochratoxin A, zearalenone and fumonisin B1) as non-mutagenic. For group 2 (trichothecenes), contradictory conclusions were obtained between the two in silico tools, being out of the applicability domain of many models. Phase 2 confirmed the results obtained in the previous phase for groups 1 and 3. It also provided extra information regarding the role of metabolic activation in aflatoxin B1 and sterigmatocystin mutagenicity. Regarding group 2, equivocal results were obtained in few experiments; however, the group was finally classified as non-mutagenic. The strategy used correlated with the published Ames tests, which detect point mutations. Few alerts for chromosome aberrations could be detected. The SOS/umu test appeared as a good screening test for mutagenicity that can be used in the absence and presence of metabolic activation and independently of Phase 1, although the in silico-in vitro combination gave more information for decision making.

Mycotoxins in herbal tea: transfer into the infusion

Mycotoxins are natural food contaminants, associated with adverse health effects due to acute intoxication and, what is much more common, chronic exposure. The most hazardous and widespread mycotoxins are subjected to regulation in food in most countries. Alongside with regulated, a wide list of mycotoxins is monitored in various foods. Traditionally mycotoxins in tea are determined in a dry sample, not taking into account their transfer rate into the infusion. This study was aimed at the determination of the transfer rate of several mycotoxins from naturally contaminated herbal tea samples into an infusion. Seven of the most contaminated samples were pre-selected during the monitoring of mycotoxins in Camellia sinensis and herbal tea available in the Russian Federation. Ochratoxin A (OTA), sterigmatocystin (STE), mycophenolic acid (MPA), tentoxin (TTX), alternariol (AOH), its methyl ether (AME), zearalenone (ZEN), enniatins A and B (ENN A and B), beauvericin (BEA) were detected in these samples in the range of several μg/kg to several mg/kg. HPLC-MS/MS was used for dry tea samples and their infusion analysis. Mycotoxin polarity and infusion pH (for analytes possessing carboxylic groups) appeared to be factors determining transfer rate. STE transferred into infusion at the average rate of 10%. Average transfer of Alternaria toxins varied from 73% (TTX) to 45% (AOH) and about 11% (AME). A third part of ZEN was detected in the infusion. Transfer of ENNs and BEA was low and did not exceed 7%. Infusion pH affected MPA transfer rate; it increased from 23% to 96% in the pH range from 5.5 to 6.3. 83% of OTA was detected in the infusion of a single contaminated sample. Consideration of the mycotoxin transfer rate to herbal tea infusions resulted in the change of the model herbal tea input into mean chronic dietary exposure for most studied mycotoxins.

Development of an in vitro neuroblastoma 3D model and its application for sterigmatocystin-induced cytotoxicity testing

Given the increasing importance of establishing better risk assessments for mycotoxins, novel in vitro tools for the evaluation of their toxicity are mandatory. In this study, an in vitro 3D spheroid model from SH-SY5Y cells, a human neuroblastoma cell line, was developed, optimized and characterized to test the cytotoxic effects caused by the mycotoxin sterigmatocystin (STE). STE induced a concentration- and time-dependent cell viability decrease in spheroids. Spheroids displayed cell disaggregation after STE exposure, increasing in a dose-dependent manner and over time. STE also induced apoptosis as confirmed by immunofluorescence staining and Western blot. Following the decreased proliferation and increased apoptosis, STE cytostasis effects were observed by migration assays both in 2D and 3D cell culture. Increased ROS generation, as well as DNA damage were also observed. Taken together, these data highlight the cytotoxic properties of STE and suggest that cell culture models play a pivotal role in the toxicological risk assessment of mycotoxins. The evaluation of cytotoxicity in spheroids (3D) rather than monolayer cultures (2D) is expected to more accurately reflect in vivo-like cell behaviour.

Aflatoxin B1 and sterigmatocystin: method development and occurrence in tea

Tea is one of the most popular beverage in the world and may be contaminated by fungi and mycotoxins during processing. To analyse aflatoxin B₁ (AFB₁) and sterigmatocystin (STC) in three types of tea, a simple, fast, sensitive and reliable method of these two myxotoxins was developed. Recoveries obtained ranged from 95.9% to 118.0% and the RSDs were between 0.3% and 11.2%. The range of LODs was 0.2-0.45 µg/kg for AFB₁ and 0.04-0.12 µg/kg for STC. The range of LOQs was 0.67-1.73 µg/kg for AFB₁ and 0.13-0.40 µg/kg for STC. The optimised procedure was applied to analyse 126 tea samples randomly collected from different markets in China. AFB₁ was not detected, but STC was determined in 17 samples with concentrations ranging from 0.13 to 4.48 µg/kg. The detection rate of STC was 5%, 8.9% and 33.3% in black tea, green tea and Oolong tea, respectively.

Biological Activity of Extracts from Aromatic Plants as Control Agents against Spoilage Molds Isolated from Sheep Cheese

The aim of this work was to assess the antifungal and antioxidant activity of essential oils and ethanolic extracts from distilled solid by-products from aromatic plants (Artemisia dracunculus, Hyssopus officinalis, Lavandula stoechas, Origanum vulgare and Satureja montana) against 14 fungi strains isolated from sheep cheese and identified at species level using DNA barcoding based on β-tubulin sequence analysis. In addition, capacity of fungi to produce ochratoxin A, patulin, cyclopiazonic acid and sterigmatocystin was analyzed. Of the isolates, 85.7% belonged to Penicillium (P. commune/biforme, P. crustosum) and 14.3% to Aspergillus (A. puulaauensis and A. jensenii), the first time that these Aspergillus species have been found in sheep's cheese. All P. commune isolates were producers of cyclopiazonic acid, and the two Aspergillus strains produced sterigmatocystin, but the others did not produce any tested mycotoxin. Among the essential oils tested, oregano, savory and tarragon had a significant antifungal activity against all the isolated strains, but no ethanolic extract showed antifungal activity. By contrast, ethanolic extracts showed great potential as antioxidants. The identification of new molds in cheese will help the dairy industry to know more about those molds affecting the sector, and the use of aromatic plants in the control of fungal spoilage could be a suitable alternative to chemical preservatives used in the agri-food industry.

Sterigmatocystin, 5-Methoxysterigmatocistin, and Their Combinations Are Cytotoxic and Genotoxic to A549 and Hepg2 Cells and Provoke Phosphorylation of Chk2, but Not Fancd2 Checkpoint Proteins

Sterigmatocystin (STC) and 5-methoxysterigmatocystin (5-M-STC) are structurally related mycotoxins with cytotoxic and genotoxic properties. In the present study, we hypothesized that DNA damage induced by non-cytotoxic concentrations of single and combined mycotoxins could alter the phosphorylation of the checkpoint proteins Chk2 and FANCD2 (ELISA) in HepG2 and A549 cells. The cytotoxic potential (MTT test) of single and combined STC and 5-M-STC, the nature of their interaction (additivity, antagonism, or synergy) and DNA damage level (alkaline comet assay) in HepG2 and A549 cells were also investigated. All experiments were performed after 24 h of mycotoxin treatment. 5-M-STC was 10-folds more cytotoxic than STC to both HepG2 and A549 cells. Both mycotoxins are genotoxic to HepG2 and A549 cells by inducing both double and single DNA strand breaks that activate Chk2 (especially in HepG2 cells) but not the FANCD2 protein. STC exerted higher genotoxic potential than 5-M-STC in HepG2 and A549 cells when both toxins were applied individually at the same concentration. Dual combinations of non-cytotoxic mycotoxin concentrations showed additive to antagonizing cytotoxic and genotoxic effects. The absence and low activation of checkpoint proteins during prolonged exposure to non-cytotoxic concentrations of STC and 5-M-STC could support cell proliferation and carcinogenesis.

Mycotoxins, Phytoestrogens and Other Secondary Metabolites in Austrian Pastures: Occurrences, Contamination Levels and Implications of Geo-Climatic Factors

Pastures are key feed sources for dairy production and can be contaminated with several secondary metabolites from fungi and plants with toxic or endocrine-disrupting activities, which possess a risk for the health, reproduction and performance of cattle. This exploratory study aimed to determine the co-occurrences and concentrations of a wide range of mycotoxins, phytoestrogens and other secondary metabolites in grazing pastures. Representative samples of pastures were collected from 18 Austrian dairy farms (one sample per farm) between April to October 2019. After sample preparation (drying and milling) the pastures were subjected to multi-metabolite analysis using LC-MS/MS. In total, 68 metabolites were detected, including regulated zearalenone and deoxynivalenol (range: 2.16-138 and 107-505 μg/kg on a dry matter (DM) basis, respectively), modified (3-deoxynivalenol-glucoside, HT-2-glucoside) and emerging Fusarium mycotoxins (e.g., enniatins), ergot alkaloids and Alternaria metabolites along with phytoestrogens and other metabolites. Aflatoxins, fumonisins, T-2 toxin, HT-2 toxin and ochratoxins were not detected. Of the geo-climatic factors and botanical diversity investigated, the environment temperature (average of 2 pre-sampling months and the sampling month) was the most influential factor. The number of fungal metabolites linearly increased with increasing temperatures and temperatures exceeding 15 °C triggered an exponential increment in the concentrations of Fusarium and Alternaria metabolites and ergot alkaloids. In conclusion, even though the levels of regulated mycotoxins detected were below the EU guidance levels, the long-term exposure along with co-occurrence with modified and emerging mycotoxins might be an underestimated risk for grazing and forage-fed livestock. The one-year preliminary data points out a dominant effect of environmental temperature in the diversity and contamination level of fungal metabolites in pastures.

Dietary exposure to mycotoxins of 1- and 2-year-old children from a Dutch Total Diet Study

In 2017, a Total Diet Study was conducted in the Netherlands in which mycotoxins were analysed in foods and beverages consumed by 1- and 2-year-old children. These mycotoxins were aflatoxins, Alternaria toxins, citrinin, ergot alkaloids, fumonisins, ochratoxin A, patulin, sterigmatocystin, trichothecenes, and zearalenone. Long-term exposure was calculated by combining concentrations in foods and beverages with consumed amounts of these products. Analysed foods and beverages with a concentration below the detection limit that could contain the mycotoxin, were assigned a concentration equal to half this limit value. To assess if the exposure could result in a possible health risk, the high long-term exposure (95th percentile) was compared with a health-based guidance value (HBGV) or a margin of exposure (MOE) was calculated. Exposure to aflatoxins, Alternaria toxins, ochratoxin A and T-2/HT-2 sum may pose a health concern. Foods that contributed most to the exposure of these mycotoxins were bread, biscuits, breakfast cereals, chocolates, dried fruit, follow-on formula and fruit juices.

Mitigation of sterigmatocystin exposure in cattle by difructose anhydride III feed supplementation and detection of urinary sterigmatocystin and serum amyloid A concentrations

We evaluated the effects of supplementing cattle feed with difructose anhydride III (DFA III) by measuring urinary sterigmatocystin (STC) concentrations using 20 Japanese Black cattle aged 9–10 months from one herd. DFA III was supplemented for 2 weeks for 10 animals, and non-treated animals served as controls. The natural STC concentration in the dietary feed was 0.06 mgkg-1 (mixture of roughage and concentrate) at the beginning of the study (Day 0). The urine STC concentration was measured using liquid chromatography with tandem mass spectrometry 1 d prior to DFA III administration, 9 and 14 d thereafter, and 9 d following supplementation cessation, concomitant with the measurement of serum amyloid A (SAA). The number of heifers in which STC was detected in the urine was low (10 %) in the DFA III group compared to that (60 %) in the control group on Day 9. After 9 d following supplementation cessation (Day 23), STC concentrations were significantly lower (P=0.032) in the DFA III group than in the control group, although there was no difference in the number of heifers in which urinary STC was detected or in SAA concentrations between the two groups. Our findings demonstrate the effect of DFA III on reducing the urinary concentration of STC in Japanese Black cattle.