Mycotoxins in maize harvested in Serbia in the period 2012-2015. Part 2: Non-regulated mycotoxins and other fungal metabolites

Occurrence of the two major regulated mycotoxins, ochratoxin A and fumonisin B1, in cereal and cereal-based products in Europe and toxicological effects: A review

Among cereal contaminants, mycotoxins are of concern due to their importance in terms of food and feed safety. The difficulty in establishing a diagnosis for mycotoxicosis relies on the fact that the effects are most often subclinical for chronic exposure and the most common scenario is multi-contamination by various toxins. Mycotoxin co-occurrence is a major food safety concern as additive or even synergic toxic impacts may occur, but also regarding current regulations as they mainly concern individual mycotoxin levels in specific foods and feed in the food chain. However, due to the large number of possible mycotoxin combinations, there is still limited knowledge on co-exposure toxicity data, which depends on several parameters. In this context, this systematic review aims to provide an overview of the toxic effects of two regulated mycotoxins, namely ochratoxin A and fumonisin B1. This review focused on the 2012-2022 period and analysed the occurrence in Europe of the selected mycotoxins in different food matrices (cereals and cereal-derived products), and their toxic impact, alone or in combination, on in vitro intestinal and hepatic human cells. To better understand and evaluate the associated risks, further research is needed using new approach methodologies (NAM), such as in vitro 3D models. KEY CONTRIBUTION: Cereals and their derived products are the most important food source for humans and feed for animals worldwide. This manuscript is a state of the art review of the literature over the last ten years on ochratoxin A and fumonisin B1 mycotoxins in these products in Europe as well as their toxicological effects, alone and in combination, on human cells. Future perspectives and some challenges regarding the assessment of toxicological effects of mycotoxins are also discussed.

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.

Biocontrol ability of Bacillus velezensis T9 against Apiospora arundinis causing Apiospora mold on sugarcane

Sugarcane (Saccharum officinarum L.) may be infected with Apiospora, which can produce the toxin 3-nitropropionic acid (3-NPA) during improper transportation and storage. The consumption of sugarcane that contains 3-NPA can lead to food poisoning. Therefore, this study sought to explore a novel biocontrol agent to prevent and control Apiospora mold. Bacteria were isolated from the soil of healthy sugarcane and identified as Bacillus velezensis T9 through colony morphological, physiological and biochemical characterization and molecular identification. The inhibitory effect of B. velezensis T9 on Apiospora mold on sugarcane was analyzed. Assays of the cell suspension of strain T9 and its cell-free supernatant showed that T9 had significant in vitro antifungal activities against Apiospora arundinis and thus, would be a likely antagonist. Scanning electron microscopy and transmission electron microscopy showed that treatment with T9 significantly distorted the A. arundinis mycelia, perforated the membrane, contracted the vesicles, and decomposed most organelles into irregular fragments. A re-isolation experiment demonstrates the ability of T9 to colonize the sugarcane stems and survive in them. This strain can produce volatile organic compounds (VOCs) that are remarkably strong inhibitors, and it can also form biofilms. Additionally, the cell-free supernatant significantly reduced the ability of A. arundinis to produce 3-NPA and completely inhibited its production at 10%. Therefore, strain T9 is effective at controlling A. arundinis and has the potential for further development as a fungal prevention agent for agricultural products.

Inhibitory effect of tannic acid on the growth of Apiospora arundinis and 3-Nitropropionic acid production

AIMS

This study aimed to investigate the inhibitory effect of tannic acid (TA) on the growth of Apiospora arundinis and 3-Nitropropionic acid (3-NPA) production.

METHODS AND RESULTS

To investigate the antifungal mechanism, the effects of TA on the hypha growth, electrical conductivity, hypha morphology, defense-related enzymes, and 3-NPA production of A. arundinis were studied. TA concentrations of 640 and 1280 μg ml-1 exhibited strong antifungal activity against A. arundinis. The results of scanning electron microscopy and transmission electron microscopy showed that the hypha of the A. arundinis was severely deformed after TA treatment, and the cell membrane was blurred and thin, vacuoles were obviously shrunken and smaller, and most of the organelles were decomposed into irregular fragments. The increased electrical conductivity and malondialdehyde content indicated that TA caused peroxidation of unsaturated fatty acids and damaged the structure of the cell membrane. The decrease of intracellular ATPase and succinate dehydrogenase content indicated that TA damaged the function of mitochondria, and participated in the inhibition of respiratory metabolism. In addition, TA significantly reduced 3-NPA production and completely inhibited 3-NPA production at 640 and 1280 μg ml-1.

CONCLUSION

TA effectively inhibited both growth of A. arundinis in vitro and 3-NPA production.

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).

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.

Climate Change-A Global Threat Resulting in Increasing Mycotoxin Occurrence

During the last decade, scientists have given increasingly frequent warnings about global warming, linking it to mycotoxin-producing moulds in various geographical regions across the world. In the future, more pronounced climate change could alter host resilience and host-pathogen interaction and have a significant impact on the development of toxicogenic moulds and the production of their secondary metabolites, known as mycotoxins. The current climate attracts attention and calls for novel diagnostic tools and notions about the biological features of agricultural cultivars and toxicogenic moulds. Since European climate environments offer steadily rising opportunities for Aspergillus flavus growth, an increased risk of cereal contamination with highly toxic aflatoxins shall be witnessed in the future. On top of that, the profile (representation) of certain mycotoxigenic Fusarium species is changing ever more substantially, while the rise in frequency of Fusarium graminearum contamination, as a species which is able to produce several toxic mycotoxins, seen in northern and central Europe, is becoming a major concern. In the following paper, a high-quality approach to a preventative strategy is tailored to put a stop to the toxicogenic mould- and mycotoxin-induced contamination of foods and feeds in the foreseeable future.

Oral exposure to citrinin significantly exacerbates the pathophysiology of a mouse model of imiquimod-induced psoriasis via direct activation of dendritic cell

Citrinin, a mycotoxin produced by Penicillium citrinum and Penicillium verrucosum, mainly contaminates cereals. The aim of study was to investigate the novel immunoreactive effect of citrinin using a mouse model of psoriasis. A mouse model of psoriasis was generated by topical application of 5% imiquimod in female BALB/c mice. Standard rodent diet and rice samples with 3 ppm of citrinin were mixed to obtain a final citrinin concentration of 0.3 ppm, and a citrinin-contaminated diet was fed to mice daily. Skin thickness, scratching behavior, and trans epidermal water loss (TEWL) were monitored continuously during the imiquimod application. Immediately after the final imiquimod application, ear skin and auricular lymph node (LN) were sampled for further analysis. Only a slight increase was observed in skin thickness in the citrinin exposure group; however, citrinin exposure significantly exacerbated hyperkeratinization and inflammatory cell infiltration in histological evaluation. TEWL, which is representative of cutaneous barrier function, was significantly increased by citrinin exposure. In terms of immune function, the number of immune cells in LN (T cells and dendritic cells) and gene expression of interleukin (IL)-17 in skin tissue were significantly increased by citrinin exposure. Direct interaction of dendritic cells (DCs) in citrinin-induced psoriasis development was further examined by proinflammatory cytokine determination in THP-1 cells and murine bone marrow derived DCs. IL-6 and/or tumor necrosis factor α were significantly increased by citrinin exposure. Taken together, our results imply that oral exposure to citrinin exacerbates the symptoms of a mouse model of psoriasis via direct activation of DCs.

Impact of Climate Changes on the Natural Prevalence of Fusarium Mycotoxins in Maize Harvested in Serbia and Croatia

Ongoing climate change may affect the susceptibility of plants to attacks by pathogenic, mostly mycotoxigenic fungi with a consequent increase in the presence of mycotoxins. Fusarium fungi represent one of the most important producers of mycotoxins, and are also important pathogens of agricultural crops. Therefore, the main aim of the study was to estimate the impact of weather parameters on the natural occurrence of Fusarium mycotoxins, such as deoxynivalenol (DON), fumonisins B₁ and B₂ (FUMs), zearalenone (ZEN), T-2, and HT-2 toxins (T-2/HT-2) in maize samples harvested from two neighboring countries, Serbia and Croatia, during a four-year production period (2018-2021). The frequency and contamination level of examined Fusarium mycotoxins varied by maize year of production and could be linked to weather conditions per investigated country. Among them, FUMs were found to be the most common contaminants (84-100%) of maize in both Serbia and Croatia. Additionally, a critical assessment of Fusarium mycotoxins occurrence in the last 10 years (2012-2021), for both Serbia and Croatia, was done. Results pointed out the highest contamination of maize from 2014, especially with DON and ZEN, in connection to extreme levels of precipitation observed in both Serbia and Croatia, whereas FUMs occurred with high prevalence from each of the ten investigated years.

Citrinin Exposure in Germany: Urine Biomarker Analysis in Children and Adults

Citrinin (CIT), a mycotoxin known to exert nephrotoxicity, is a contaminant in food and feed. Since CIT contamination is not regularly analyzed, data on its occurrence and especially levels in food commodities are insufficient for conducting a conventional exposure assessment. Yet, human biomonitoring, i.e., an analysis of CIT and its metabolite dihydrocitrinone (DH-CIT) in urine samples allows to estimate exposure. This study investigated CIT exposure in young (2-14 years) and adult (24-61 years) residents of three federal states in Germany. A total of 179 urine samples from children and 142 from adults were collected and analyzed by a targeted LC-MS/MS based method for presence of CIT and DH-CIT. At least one of the biomarkers was detected and quantified in all urines, which indicated a widespread dietary exposure to the mycotoxin in Germany. Interestingly, the biomarker concentrations of CITtotal (sum of CIT and DH-CIT) were higher in children's urine (range 0.05-7.62 ng/mL; median of 0.54 ng/mL) than in urines from adults (range 0.04-3.5 ng/mL; median 0.3 ng/mL). The biomarker levels (CITtotal) of individual urines served to calculate the probable daily CIT intake, for comparison to a value of 0.2 µg/kg bw/day defined as 'level of no concern for nephrotoxicity' by the European Food Safety Authority. The median exposure of German adults was 0.013 µg/kg b.w., with only one urine donor exceeding this provisional tolerable daily intake (pTDI) for CIT. The median exposure of children was 0.05 µg/kg bw per day (i.e., 25% of the pTDI); however, CIT exposure in 12 individuals (6.3% of our study group) exceeded the limit value, with a maximum intake of 0.46 µg/kg b.w. per day. In conclusion, these results show evidence for non-negligible exposure to CIT in some individuals in Germany, mainly in children. Therefore, further biomonitoring studies and investigations aimed to identify the major sources of CIT exposure in food commodities are required.

Simultaneous Determination of 11 Mycotoxins in Maize via Multiple-Impurity Adsorption Combined with Liquid Chromatography-Tandem Mass Spectrometry

In this study, multiple-impurity adsorption purification (MIA) technologies and liquid chromatography−tandem mass spectrometry (LC-MS/MS) were used to establish a method for detecting 11 mycotoxins in maize. The conditions for mass spectrometry and MIA were optimized. Maize was extracted with 70% acetonitrile solution, enriched, and purified using MIA technologies, and then, analyzed via LC-MS/MS. The results showed that the linear correlation coefficients of the 11 mycotoxins were >0.99, the sample recoveries ranged from 77.5% to 98.4%, and the relative standard deviations were <15%. The validated method was applied to investigate actual samples, and the results showed that the main contaminating toxins in maize were aflatoxins (AFs), deoxynivalenol (DON), fumonisins (FBs), ochratoxin A (OTA), and zearalenone (ZEN). Additionally, simultaneous contamination by multiple toxins was common. The maximum detection values of the mycotoxins were 77.65, 1280.18, 200,212.41, 9.67, and 526.37 μg/kg for AFs, DON, FBs, OTA, and ZEN, respectively. The method is simple in pre-treatment, convenient in operation, and suitable for the simultaneous determination of 11 types of mycotoxins in maize.

Mixtures of mycotoxins, phytoestrogens and pesticides co-occurring in wet spent brewery grains (BSG) intended for dairy cattle feeding in Austria

Spent brewery grains (BSG) are the main by-product of beer production and are incorporated in rations of food-delivering animals, mainly dairy cows. Like other agricultural commodities, BSG can be contaminated by a broad spectrum of natural and synthetic undesirable substances, which can be hazardous to animal and human health as well as to the environment. The co-occurrence of mycotoxins, phytoestrogens, other fungal and plant secondary metabolites, along with pesticides, was investigated in 21 BSG samples collected in dairy farms in Austria. For this purpose, a validated multi-metabolite liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) was employed. Metabolites derived from Fusarium, Aspergillus, Alternaria and pesticide residues, were ubiquitous in the samples. Zearalenone (ZEN), T-2 and HT-2 toxins were the only regulated mycotoxin detected, albeit at concentrations below the European guidance values for animal feeds. Ergot alkaloids, Penicillium-derived metabolites, and phytoestrogens had occurrence rates of 90, 48 and 29%, respectively. Penicillium metabolites presented the highest levels among the fungal compounds, indicating contamination during storage. Aflatoxins (AFs), ochratoxins and deoxynivalenol (DON) were not detected. Out of the 16 detected pesticides, two fungicides, ametoctradin (9.5%) and mandipropamid (14.3%) revealed concentrations exceeding their respective maximum residue level (MRL) (0.01 mg kg^-1) for barley in two samples. Although based on European guidance and MRL values the levels of the detected compounds probably do not pose acute risks for cattle, the impact of the long-time exposure to such mixtures of natural and synthetic toxicants on animal health and food safety are unknown and must be elucidated.

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.

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.

Citrinin Mycotoxin Contamination in Food and Feed: Impact on Agriculture, Human Health, and Detection and Management Strategies

Citrinin (CIT) is a mycotoxin produced by different species of Aspergillus, Penicillium, and Monascus. CIT can contaminate a wide range of foods and feeds at any time during the pre-harvest, harvest, and post-harvest stages. CIT can be usually found in beans, fruits, fruit and vegetable juices, herbs and spices, and dairy products, as well as red mold rice. CIT exerts nephrotoxic and genotoxic effects in both humans and animals, thereby raising concerns regarding the consumption of CIT-contaminated food and feed. Hence, to minimize the risk of CIT contamination in food and feed, understanding the incidence of CIT occurrence, its sources, and biosynthetic pathways could assist in the effective implementation of detection and mitigation measures. Therefore, this review aims to shed light on sources of CIT, its prevalence in food and feed, biosynthetic pathways, and genes involved, with a major focus on detection and management strategies to ensure the safety and security of food and feed.

The natural occurrence of Penicillium spp. metabolites in maize kernels originating from Serbia

Maize can be contaminated with a wide range of fungal secondary metabolites that decrease the quality and safety of maize and maize-derived products. The increase of natural fungal metabolites occurrence in maize, influenced by climate changes, is recognized as a significant issue in recent years. Therefore, the main aim of this study was to investigate the influence of weather conditions on the natural occurrence of Penicillium spp. metabolites in maize kernel samples. The survey was conducted for two maize vegetation seasons 2016 and 2017. In total 458 maize samples were analyzed by liquid chromatography-tandem mass spectrometry method. The samples originated from the Autonomous Province of Vojvodina, and regions of Bačka, Srem, and Banat. Among 45 Penicillium metabolites investigated 16 and 18 were detected in samples from 2016 and 2017, respectively. The most commonly occurring Penicillium metabolite in both years was oxaline, which was detected in more than 90% of analyzed samples. Questiomycin A, 7hydroxypestalotin, pestalotin, and mycophenolic acid were also very frequently detected Penicillium metabolites. This is one of the unique studies in the Republic of Serbia, as well as in this part of Europe, investigating the occurrence of a great number of Penicillium metabolites in maize samples.

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.

The natural occurrence of Penicillium spp. metabolites in maize kernels originating from Serbia

Maize can be contaminated with a wide range of fungal secondary metabolites that decrease the quality and safety of maize and maize-derived products. The increase of natural fungal metabolites occurrence in maize, influenced by climate changes, is recognized as a significant issue in recent years. Therefore, the main aim of this study was to investigate the influence of weather conditions on the natural occurrence of Penicillium spp. metabolites in maize kernel samples. The survey was conducted for two maize vegetation seasons 2016 and 2017. In total 458 maize samples were analyzed by liquid chromatography-tandem mass spectrometry method. The samples originated from the Autonomous Province of Vojvodina, and regions of Bačka, Srem, and Banat. Among 45 Penicillium metabolites investigated 16 and 18 were detected in samples from 2016 and 2017, respectively. The most commonly occurring Penicillium metabolite in both years was oxaline, which was detected in more than 90% of analyzed samples. Questiomycin A, 7hydroxypestalotin, pestalotin, and mycophenolic acid were also very frequently detected Penicillium metabolites. This is one of the unique studies in the Republic of Serbia, as well as in this part of Europe, investigating the occurrence of a great number of Penicillium metabolites in maize samples.

Fusarium metabolites in maize from regions of Northern Serbia in 2016-2017

The main objective of this study was to determine the presence of Fusarium metabolites in maize samples collected from different regions of Northern Serbia (Bačka, Banat and Srem) during a period of two years (2016-2017). A total of 458 maize samples were analysed by liquid chromatography-tandem mass spectrometry. A total of 40 metabolites were detected, where 94% of the samples contained at least 5 metabolites. Fumonisins (including B₁, B₂, B₃ and B₄), moniliformin and bikaverin were the most frequent (80-98%) Fusarium metabolites in both years. Furthermore, in samples from 2016, fumonisin A₁ and A₂, deoxynivalenol, deoxynivalenol-3-glucoside, zearalenone, culmorin, 15-hydroxyculmorin, fusapyron, fusaproliferin and aurofusarin were detected with frequencies of 58-80%. Levels of certain Fusarium metabolites in 2016 were higher on average due to increased humidity when compared to 2017, which was characterised by warm and dry conditions.

Mycotoxins survey in feed materials and feedingstuffs in years 2015-2020

Mycotoxins are secondary metabolites produced by several fungi, mainly from Penicillium, Fusarium, and Aspregillus genera. They can contaminate many raw materials both in the field and during storage under very different conditions. This study aimed to evaluate mycotoxin contamination levels of raw materials and products for animals in Poland in the years 2015-2020. Producers, farmers, and veterinary doctors delivered a total of 3980 samples (642 maize samples, 2027 feed samples, 990 small grain samples, 142 maize silage samples and 179 TMR samples). Samples were analyzed for the occurrence of several mycotoxins, including aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, nivalenol, T-2 toxin, H-2 toxin, and zearalenone. Trichothecenes, zearalenone, and fumonisins were determined using the LC-MS/MS technique. Ochratoxin A and aflatoxins were determined using the HPLC-FLD method. Deoxynivalenol and zearalenone were the most common contamination in maize samples (97.3% and 98.4%, respectively) and feed samples (99.7% and 100% samples, respectively). They were also present in all maize silage and TMR samples. The highest concentration levels of deoxynivalenol and zearalenone were 16,889 μg/kg in the wheat sample and 1420 μg/kg in the maize sample. Additionally, in 51 samples, mycotoxins level (mainly deoxynivalenol and zearalenone levels) was above recommended levels set by the European Union. The present study showed that both feeding and raw materials are contaminated by mycotoxins, often by more than one.

Emerging mycotoxins in infant and children foods: A review

A proper nutrition is crucial for children's healthy development. Regardless of the usual recommendations to follow a varied diet, some foods can be a source of toxic natural contaminants such as mycotoxins, potent secondary metabolites produced by filamentous fungi. In addition to the most well-known mycotoxins, many of which are subject to tight regulation regarding the maximum levels allowed in different types of food, there is a large group of mycotoxins, the so-called emerging mycotoxins, about which less knowledge has already been acquired, which have gradually been the target of interest from the scientific community due to their prevalence in most foodstuffs, particularly in cereals and cereal-based products. Alternariol and his metabolite alternariol mono-methyl ether, beauvericin, citrinin, culmorin, enniatins, ergot alkaloids, fusaproliferin, kojic acid, moniliformin, sterigmatocystin, tentoxin and tenuazonic acid are the most representative of them. The current review gathered the information of the last ten years that have been published on the levels of emerging mycotoxins in food products dedicated for infants and children. European Union countries are responsible for most of the reported studies, which showed levels that can reach hundreds of mg/kg.

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.

Fungi and their metabolites in grain from individual households in Croatia

A total of 117 fungal metabolites were detected in grains collected in Gunja-G (flooded village) and Gornji Stupnik-GS (control village), located in the Zagreb County, Croatia. Major mycotoxins and derivatives (17), ergot alkaloids (14), Fusarium (23), Aspergillus (18), Penicillium (18), Alternaria (7) and other fungal and unspecific metabolites (20) were found. A higher number of metabolites co-occurred per sample in grains from G (115) than in GS (91). Regulated mycotoxins were below maximum limits except fumonisins B_1,2 in 15-20% of grains and aflatoxin B_1. Fusarium metabolites contaminated more than 50% of grains at both locations. Besides FB_1,2, bikaverin, aurofusarin, culmorin and 15-hidroxyculmorin were detected at relatively high concentrations. Ergot alkaloids were detected at 2-18 times higher concentrations in grains from G as compared to GS. Majority of Aspergillus mycotoxins were present at a low frequency (5-15%). Penicillium metabolites recovered with higher frequency in GS (55-70%) than in G (20-55%). Alteranaria metabolites prevailed in grains from G (60-80%).

Versicolorin A enhances the genotoxicity of aflatoxin B1 in human liver cells by inducing the transactivation of the Ah-receptor

Aflatoxins are a group of mycotoxins that have major adverse effects on human health. Aflatoxin B1 (AFB1) is the most important aflatoxin and a potent carcinogen once converted into a DNA-reactive form by cytochrome P450 enzymes (CYP450). AFB1 biosynthesis involves the formation of Versicolorin A (VerA) which shares structural similarities with AFB1 and can be found in contaminated commodities, often co-occurring with AFB1. This study investigated and compared the toxicity of VerA and AFB1, alone or in combination, in HepG2 human liver cells. Our results show that both toxins have similar cytotoxic effects and are genotoxic although, unlike AFB1, the main genotoxic mechanism of VerA does not involve the formation of DNA double-strand breaks. Additionally, we show that VerA activates the aryl hydrocarbon receptor (AhR) and significantly induce the expression of the CYP450-1A1 (CYP1A1) while AFB1 did not induce AhR-dependent CYP1A1 activation. Combination of VerA with AFB1 resulted in enhanced genotoxic effects, suggesting that AhR-activation by VerA influences AFB1 genotoxicity by promoting its bioactivation by CYP450s to a highly DNA-reactive metabolite. Our results emphasize the need for expanding the toxicological knowledge regarding mycotoxin biosynthetic precursors to identify those who may pose, directly or indirectly, a threat to human health.

Co-occurrence and toxicological relevance of secondary metabolites in dairy cow feed from Thailand

The occurrence of secondary metabolites and co-contaminants in dairy cow feed samples (n = 115), concentrate, roughage, and mixed feed, collected from Ratchaburi and Kanjanaburi provinces, Thailand, between August 2018 and March 2019 were investigated using LC-MS/MS based multi-toxin method. A total of 113 metabolites were found in the samples. Fungal metabolites were the predominant compounds, followed by plant metabolites. Among major mycotoxins, zearalenone and fumonisins were most frequently detected in concentrate and mixed feed samples, while deoxynivalenol and aflatoxin B₁ were found at the frequency lower than 50%. Other metabolites, produced by Aspergillus, Fusarium, Penicillium, and Alternaria species, occurred in the samples. Flavoglaucin, 3-nitropropionic acid, averufin, and sterigmatocystin were the most prevalent Aspergillus metabolites. Common Fusarium metabolites occurring in the samples included moniliformin, beauvericin, and enniatins. For Penicillium metabolites, mycophenolic acid, questiomycin A, quinolactacin A, oxaline, citrinin, and dihydrocitrinone were frequently detected. The toxic Alternaria metabolites, alternariol, and alternariol monomethyl ether showed the high incidence in the samples. Plant metabolites were commonly found, mainly cyanogenic compounds and isoflavones, from cassava and soybean meal used as feed ingredients. Overall, 96.6% of feed samples contained at least two metabolites, in a range from 2 to 69. According to co-contamination of mycotoxins found in feed samples, zearalenone were mostly found in combination with fumonisin B₁, deoxynivalenol, and aflatoxin B₁. Fumonisin B₁ co-occurred with aflatoxin B₁ and deoxynivalenol. The mixtures of deoxynivalenol and aflatoxin B₁, and of zearalenone, fumonisin B₁ and deoxynivalenol were also found. Due to known individual toxicity of fungal and plant metabolites and possible additive or synergistic toxic effects of multi-mycotoxins, the occurrence of these metabolites and co-contaminants should be monitored continuously to ensure food safety through the dairy supply chain.

Citrinin in Foods and Supplements: A Review of Occurrence and Analytical Methodologies

Citrinin (CIT) deserves attention due to its known toxic effects in mammalian species and its widespread occurrence in food commodities, often along with ochratoxin A, another nephrotoxic mycotoxin. Human exposure, a key element in assessing risk related to food contaminants, depends upon mycotoxin contamination levels in food and on food consumption. Commercial supplements, commonly designated as red rice, usually used in daily diets in Asiatic countries due to their medicinal properties, may pose a health problem as a result of high CIT levels. In addition to the worldwide occurrence of CIT in foods and supplements, a wide range of several analytical and detection techniques with high sensitivity, used for evaluation of CIT, are reviewed and discussed in this manuscript. This review addresses the scientific literature regarding the presence of CIT in foods of either vegetable or animal origin, as well as in supplements. On what concerns analytical methodologies, sample extraction methods, such as shaking extraction and ultrasonic assisted extraction (UAE), clean-up methods, such as liquid-liquid extraction (LLE), solid phase extraction (SPE) and Quick, Easy, Cheap, Effective, Rugged and Safe (QuECHERS), and detection and quantification methods, such as thin layer chromatography (TLC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), biosensors, and ELISA, are also reviewed.

Fungal diversity and metabolomic profiles in GM and isogenic non-GM maize cultivars from Brazil

There is little knowledge of the microbial diversity, mycotoxins and associated secondary metabolites in GM maize and isogenic non-GM cultivars (cvs). This study has quantified the microbial populations and dominant fungal genera in 6 cvs of each type representative of herbicide, pesticide or stacked resistance to both. The predominant mycotoxins and targeted metabolomics profiles were also compared between the two sets of cvs. This showed that the overall fungal populations were 8.8 CFUs g⁻¹ maize. The dominant genera, isolated from maize samples, whether surface-sterilised or not, in all maize cvs were Fusarium, followed by Penicillium, Aspergillus and occasionally Cladosporium and Alternaria. The analysis of the targeted metabolomics showed that approx. 29 different metabolites were detected. These were dominated by fumonisins and minor Penicillium spp. metabolites (questiomycin A and rugulovasine A). Interestingly, the range and number of mycotoxins present in the GM cvs were significantly lower than in the non-GM maize samples. This suggests that while the fungal diversity of the two types of maize appeared to be very similar, the major contaminant mycotoxins and range of toxic secondary metabolites were much lower in the GM cvs.

Pre-Concentration and Analysis of Mycotoxins in Food Samples by Capillary Electrophoresis

Mycotoxins are considered one of the most dangerous agricultural and food contaminants. They are toxic and the development of rapid and sensitive analytical methods to detect and quantify them is a very important issue in the context of food safety and animal/human health. The need to detect mycotoxins at trace levels and to simultaneously analyze many different mycotoxin types became mandatory to protect public health. In fact, European Commission regulations specified both their limits in foodstuffs and official sample preparation protocols in addition to analytical methods to verify their presence. Capillary Electrophoresis (CE) includes different separation modes, allowing many versatile applications in food analysis and safety. In the context of mycotoxins, recent advances to improve CE sensitivity, particularly pre-concentration techniques or miniaturized systems, deserve remarkable attention, as they provide an interesting approach in the analysis of such contaminants in complex food matrices. This review summarizes the applications of CE combined with different pre-concentration approaches, which have been proposed in the literature (mainly) in the last ten years. A section is also dedicated to recent microchip–CE devices since they represent the most promising CE mode for this application.

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.

Awareness of mycotoxins and occurrence of aflatoxins in poultry feeds and feed ingredients in selected regions of Uganda

Background

Aflatoxins are a category of mycotoxins produced by certain molds naturally occurring as food and feed contaminants with toxic effects to both animals and humans. In Uganda, previous studies on aflatoxins mainly considered human foods, but scarce information exists for animal feeds. The study aimed at establishing the current status of aflatoxins contamination of poultry feeds, level of awareness and the existing technological challenges and innovations to mycotoxin control in Uganda.

Method

Mycotoxin awareness, predisposing factors and existing strategies for managing mycotoxin contamination were investigated through focus group discussions and questionnaires with selected processors and farmers. Poultry feed and feed ingredient samples were collected and analyzed for total aflatoxins using VICAM Fluorimeter procedure for foods and animal feeds.

Results

Majority of the farmers and processors (> 50%) had limited knowledge about aflatoxins; contamination predisposing factors; dangers to animals and humans; and mitigation strategies. The study further revealed poor feed and feed ingredients handling and storage practices that predispose to mold/aflatoxin contamination. Forty feed samples from feed processing plants had aflatoxins in the range 7.5 ± 0.71 to 393.5 ± 19.09 parts per billion (ppb) with only twelve samples being within the generally acceptable limits of 20 ppb as recommended by the Food and Agricultural Organisation and the United States Federal Department of Agriculture. Additionally, all 27 feed samples obtained from the farmers had aflatoxins in the range of 19.0 ± 1.41 to 188.5 ± 2.12 ppb and were above the acceptable limit. Generally, broiler feeds were the most contaminated with aflatoxins. Of the feed ingredients tested, silver fish (Rastrineobola argentea, locally known as “mukene”) had the least concentration (8.7 ± 3.18 ppb) of aflatoxins while maize bran had the highest level of contamination, 103.3 ± 22.98 ppb.

Conclusion

Given the lack of awareness and the high prevalence of aflatoxin contaminated poultry feeds and feed ingredients in Uganda, a higher risk for carryover of the toxins into the animal products for human consumption exist. Hence, the need for comprehensive establishment of the prevention, control and surveillance strategies for reducing mycotoxins in foods.