Emerging mycotoxins in the food chain

Moniliformin Occurrence in Serbian Maize over Four Years: Understanding Weather-Dependent Variability

Moniliformin (MON) represents one of the most widespread emerging mycotoxins, whose presence in food and feed can potentially cause harmful effects on the health of both the public and animals. In order to investigate MON occurrence, a total of four hundred (n = 400) samples of unprocessed maize were sampled from different regions (Bačka, Banat, and Srem) of Serbia during a period of four years (2018-2021) and were analyzed using a validated liquid chromatography with tandem mass spectrometry (LC-MS/MS) method. The influence of regional differences and variations from year to year in terms of weather conditions on the occurrence of MON was also assessed. The obtained validation parameters indicated that the LC-MS/MS method is applicable to the determination of MON in maize samples. It can be observed from the acquired findings that all samples were contaminated with MON, while concentration levels varied between the samples, especially from different sampling years. The maize samples showed the greatest levels of MON concentration during the dry and hot climatic conditions experienced in 2021. In maize samples harvested in the period 2018-2020, the MON concentration levels detected were about two to three times lower compared to the year 2021. Additionally, a comprehensive investigation into the correlation between weather conditions and the occurrence of MON in maize grown in Serbia was undertaken by reviewing the outcomes of research undertaken in the past decade.

Enniatin B1: Emerging Mycotoxin and Emerging Issues

Although over the last 10 years several studies have focused on the emerging mycotoxins known as enniatins (ENNs), there is still a lack of knowledge regarding their toxicological effects and the development of a correct risk assessment. This is especially true for enniatin B1 (ENN B1), considered the younger sister of the widely studied enniatin B (ENN B). ENN B1 has been found in several food commodities and, as with other mycotoxins, presents antibacterial and antifungal properties. On the other hand, ENN B1 has shown cytotoxic activity, impairment of the cell cycle, the induction of oxidative stress, and changes in mitochondrial membrane permeabilization, as well as negative genotoxic and estrogenic effects. Overall, considering the paucity of information available regarding ENN B1, further studies are necessary to perform a risk assessment. This review summarizes information on the biological characteristics and toxicological effects of ENN B1 as well as the future challenges that this mycotoxin could present.

Hazard characterisation for significant mycotoxins in food

This review updates the current status of activities related to hazard characterisation for mycotoxins, with special reference to regulatory work accomplished within the European Union. Because the relevant information on these topics is widely scattered in the scientific literature, this review intends to provide a condensed overview on the most pertinent aspects. Human health risk assessment is a procedure to estimate the nature and potential for harmful effects of mycotoxins on human health due to exposure to them via contaminated food. This assessment involves hazard identification, hazard characterisation, exposure assessment, and risk characterisation. Mycotoxins covered in this review are aflatoxins, ochratoxin A, cyclopiazonic acid, citrinin, trichothecenes (deoxynivalenol, nivalenol, T-2, and HT-2 toxins), fumonisins, zearalenone, patulin, and ergot alkaloids. For mycotoxins with clear genotoxic/carcinogenic properties, the focus is on the margin of exposure approach. One of its goals is to document predictive characterisation of the human hazard, based on studies in animals using conditions of low exposure. For the other, non-genotoxic toxins, individual 'no adverse effect levels' have been established, but structural analogues or modified forms may still complicate assessment. During the process of hazard characterisation, each identified effect is assessed for human relevance. The estimation of a 'safe dose' is the hazard characterisation endpoint. The final aim of all of these activities is to establish a system, which is able to minimise and control the risk for the consumer from mycotoxins in food. Ongoing research on mycotoxins constantly comes up with new findings, which may have to be implemented into this system.

Mycotoxins Contamination in Rice: Analytical Methods, Occurrence and Detoxification Strategies

The prevalence of mycotoxins in the environment is associated with potential crop contamination, which results in an unavoidable increase in human exposure. Rice, being the second most consumed cereal worldwide, constitutes an important source of potential contamination by mycotoxins. Due to the increasing number of notifications reported, and the occurrence of mycotoxins at levels above the legislated limits, this work intends to compile the most relevant studies and review the main methods used in the detection and quantification of these compounds in rice. The aflatoxins and ochratoxin A are the predominant mycotoxins detected in rice grain and these data reveal the importance of adopting safety storage practices that prevent the growth of producing fungi from the Aspergillus genus along all the rice chain. Immunoaffinity columns (IAC) and QuECHERS are the preferred methods for extraction and purification and HPLC-MS/MS is preferred for quantification purposes. Further investigation is still required to establish the real exposition of these contaminants, as well as the consequences and possible synergistic effects due to the co-occurrence of mycotoxins and also for emergent and masked mycotoxins.

Determination of Alternaria Toxins in Food by SPE and LC-IDMS: Development and In-House Validation of a Candidate Method for Standardisation

Alternaria toxins (ATs) are frequently found contaminants in foodstuffs (e.g., alternariol), often reaching high concentrations (e.g., tenuazonic acid). They can spoil a wide variety of food categories (e.g., cereals, vegetables, seeds and drinks) and storage at fridge temperatures does not prevent the growth of Alternaria fungi. Therefore, reliable and validated analytical methods are needed to protect human health and to ensure a transparent and fair trade. This paper describes new technical features that improved a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the analysis of ATs in tomato, wheat and sunflower seeds. This analytical method should be simple to implement in different laboratories across the EU and thus be an attractive candidate for standardisation. The major element for improvement was the use of isotopically labelled internal standards, only recently commercially available, thereby reducing the sample handling and improving the accuracy of the results. In addition, the sample extraction and the solid-phase extraction (SPE) enrichment/clean-up were fine-tuned, whereas a more suitable analytical column (XSelect HSS T3) with improved selectivity was also employed. Overall, this method shows adequate precision (repeatability < 5.7% RSD; intermediate precision < 7.0% RSD) and trueness (recoveries ranging from 74% to 112%). The limits of quantification in wheat (the most analytically demanding matrix) vary between 0.19 and 1.40 µg/kg. These figures were deemed satisfactory by the European Committee for Standardization (CEN) and have formed the basis for a subsequent interlaboratory validation study. The corresponding standard was published by CEN in 2021.

An update on immunotoxicity and mechanisms of action of six environmental mycotoxins

Paradoxically, aflatoxin B1 (AFB1), ochratoxin A (OTA), deoxynivalenol (DON), T-2 toxin (T-2), fumonisin B1 (FB1), and zearalenone (ZEA) have both immunosuppressive and immunostimulatory effects. The immunotoxicity of six mycotoxins exhibits immune suppression or stimulation, which depends on multiple factors. Low doses of mycotoxins can induce an inflammatory response, but elevated levels of ones can induce immunosuppression; long-term instead of short-term mycotoxin exposure is immunosuppressive. These six mycotoxins play anti-inflammatory roles when the immunologic stimulants are present but pro-inflammatory roles when the immunologic stimulants are absent. Pigs are most sensitive animals to mycotoxins, followed by humans and poultry, rodent, and marine organism, and ruminants are the least susceptible. Female animals are more susceptible to mycotoxins than male ones. The immunosuppresion mechanism of mycotoxins are mainly in, oxidative stress, apoptosis and autophagy of immune cells, as well as inhibits the immunity-related signal pathways; and AFB1, OTA, DON, and T-2 induce immunostimulation via directly activating the TLRs/NF-κB pathway and other crossing pathways including cyclooxygenase-2 (COX-2) and mitogen-activated protein kinase (MAPK). This review strongly dispels the viewpoint that "immunotoxicity is equivalent to immunosuppression", clearly demonstrates the mechanistic pathway and how it contributes to immunosuppression or immunostimulation, thereby providing reliable references for future studies.

Organic vs conventional plant-based foods: A review

Organic farming is characterized by the prohibition of the use of chemical synthetic fertilizers, pesticides, feed additives and genetically modified organisms and by the application of sustainable agricultural technologies based on ecological principles and natural rules. Organic products are believed to be more nutritious and safer foods compared to the conventional alternatives by consumers, with the consequent increase of demand and price of these foodstuffs. However, in academic circles there is much debate on these issues, since there is not a clear scientific evidence of the difference on the environmental impact and on the nutritional quality, safety and health effects between conventional and organic foods. Therefore, this work aims to describe and update the most relevant data on organic foods, by describing the impact of this practice on environment, producers, consumers and society, as well as by comparing the physicochemical, nutritional and phytochemical quality of conventional and organic plant foods.

Fungal Endophytes of Vitis vinifera—Plant Growth Promoters or Potentially Toxinogenic Agents?

Fungal endophytes occurring in grapevine (Vitis vinifera L.) are usually important sources of various compounds with biological activities with great potential for use in agriculture. Nevertheless, many species isolated from this plant belong to the genera Fusarium, Alternaria, or Aspergillus, all of which are well-known to produce mycotoxins. Our study is focused on the assessment of the toxinogenic potential of fungal endophytes isolated from vineyards in the Czech Republic. In total, 20 endophytic fungal species were cultivated in wine must, and 57 mycotoxins of different classes were analysed by liquid chromatography coupled with mass spectrometry. As a result, alternariol, tentoxin, meleagrin, roquefortine C, gliotoxin, and verruculogen were detected in the culture medium, of which verruculogen followed by gliotoxin were the most frequent (present in 90 and 40% of samples, respectively) and most concentrated (up to thousands ng/mL). The alternaria mycotoxins alternariol and tentoxin were detected not only in Alternaria sp. cultures, but traces of these mycotoxins were also quantified in the Diatripe and Epicoccum cultures. Meleagrin and roquefortine C were detected in Didymella sancta and Penicillium crustosum, gliotoxin was detected in Alternaria sp., Didymella sp., Aureobasidium pullulans, Cladosporium herbarum, Penicillium crustosum and Pleurophoma ossicola, and verruculogen was quantified in 99% of endophytic isolates investigated. The potential of endophytes to produce mycotoxins should be carefully checked, specifically in cases where they are intended for the purpose of V. vinifera growing.

A global systematic review and meta-analysis of concentration and prevalence of mycotoxins in birds' egg

In the current study, the concentration and prevalence of birds' egg's mycotoxins among 11 articles (66 studies) based on countries, part of eggs, and type of mycotoxins subgroups were meta-analyses using a random-effect model. The order of mycotoxin according to concentration of mycotoxin was Deoxynivalenol (20.083 μg/kg) > Zearalenone (2.065 μg/kg) > Enniatin (1.120 μg/kg) > Total aflatoxin (0.371 μg/kg) > Beauvericin (0.223 μg/kg) > Ochratoxins (0.087 μg/kg) > Citrinin (0.010 μg/kg). Further, the mycotoxins' concentration in the yolk part (2.070 μg/kg) was higher than the mixed eggs (0.283 μg/kg). The rank order of mycotoxin based on country was China (14.990 μg/kg) > Cameroon (7.594 μg/kg) > Thailand (1.870 μg/kg) > Finland (0.920 μg/kg) > Iran (0.312 μg/kg) > Jordan (0.202 μg/kg) > Belgium (0.183 μg/kg) > Spain (<Lod μg/kg) > South Korea (<Lod μg/kg). The rank order of mycotoxins based on prevalence was BEA (99.73%) > DON (85.00%) > AFT (20.15%) > OT (16.00%). The overall prevalence of mycotoxin was equal to 29.65%. Also, the concentration of mycotoxins in China and Cameroon was higher than in other countries. Therefore, the monitoring programs to reduce mycotoxins in bird eggs consumed in some countries such as China and Cameroon should be considered.

Integrated Mycotoxin Management System in the Feed Supply Chain: Innovative Approaches

Exposure to mycotoxins is a worldwide concern as their occurrence is unavoidable and varies among geographical regions. Mycotoxins can affect the performance and quality of livestock production and act as carriers putting human health at risk. Feed can be contaminated by various fungal species, and mycotoxins co-occurrence, and modified and emerging mycotoxins are at the centre of modern mycotoxin research. Preventing mould and mycotoxin contamination is almost impossible; it is necessary for producers to implement a comprehensive mycotoxin management program to moderate these risks along the animal feed supply chain in an HACCP perspective. The objective of this paper is to suggest an innovative integrated system for handling mycotoxins in the feed chain, with an emphasis on novel strategies for mycotoxin control. Specific and selected technologies, such as nanotechnologies, and management protocols are reported as promising and sustainable options for implementing mycotoxins control, prevention, and management. Further research should be concentrated on methods to determine multi-contaminated samples, and emerging and modified mycotoxins.

Feedborne Mycotoxins Beauvericin and Enniatins and Livestock Animals

Mycotoxins are secondary metabolites produced by several species of fungi, including the Fusarium, Aspergillus, and Penicillium species. Currently, more than 300 structurally diverse mycotoxins are known, including a group called minor mycotoxins, namely enniatins, beauvericin, and fusaproliferin. Beauvericin and enniatins possess a variety of biological activities. Their antimicrobial, antibiotic, or ionoforic activities have been proven and according to various bioassays, they are believed to be toxic. They are mainly found in cereal grains and their products, but they have also been detected in forage feedstuff. Mycotoxins in feedstuffs of livestock animals are of dual concern. First one relates to the safety of animal-derived food. Based on the available data, the carry-over of minor mycotoxins from feed to edible animal tissues is possible. The second concern relates to detrimental effects of mycotoxins on animal health and performance. This review aims to summarize current knowledge on the relation of minor mycotoxins to livestock animals.

QuEChERS-LC-QTOFMS for the simultaneous determination of legislated and emerging mycotoxins in malted barley and beer using matrix-matched calibration as a solution to the commercial unavailability of internal standards for some mycotoxins

The combination of QuEChERS-LC-QTOFMS and matrix-matched calibration (MMC) to simultaneously determinate legislated and emerging mycotoxins in malt and beer was evaluated for the first time. The method performance was satisfactory displaying suitable linearity (R² >0.99) and recovery (71-102%). The lowest values (in μg kg^-1) of LOD (0.01) and LOQ (0.05) were found for enniatins, while the highest LOD (15) and LOQ (50) were reported for fumonisin B1. Precision and sensitivity (RSD <10%) were in accordance with the different guidelines of method validation. MMC was important to avoid inaccurate quantification of all mycotoxins due to signal enhancement or suppression. Another advantage was the enhanced throughput, requiring 1.2 min of analysis per analyte. The detection of legislated (aflatoxins, ochratoxin A, deoxynivalenol, fumonisin B1, zearalanone, T-2 and HT-2 toxin) and emerging mycotoxins (enniatins, beauvericin, moniliformin and sterigmatocystin) allowed verifying compliance with legislation and generating data to support the establishment of limits for emerging mycotoxins.

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

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