Food consumption habits have been changing rapidly over the last decades, and the impact of these changes on the levels of dietary exposure to mycotoxins could be relevant. In this paper, trends in availability of specific foods that are most affected by mycotoxins were analysed, and comparisons were made among different world regions. The food commodities that have been registering very high availability levels and annual increases over the last 20 years are groundnuts and nuts in Africa and Asia, and maize in Africa, which represent an important part of the diets in those regions. Other foods, which are regularly consumed only by subgroups of populations, show increasing trends in many high- or medium-income regions. Eastern Europe, Northern Europe, Australia & New Zealand, Western Africa and Eastern Asia are the regions experiencing the most dynamic changes in availability for selected foods. As individual food consumption is determined, among others, by personal risk perceptions, a literature review on the level and drivers of awareness and perception of mycotoxin risks was conducted. The scarce evidence found show a very low level of awareness and a generally moderate perception of risks derived from mycotoxin exposure, lower than risk perceptions associated with other foodborne hazards. Among the determinants of perceived risks, the education level emerges as being inversely related to the risk perception. More research is needed on these aspects, in order to better inform risk management and communication strategies related to mycotoxins.

Aspergillus flavus is an opportunistic and pathogenic fungus that infects several crops of agricultural importance and under certain conditions may produce carcinogenic mycotoxins. Rising global temperatures, disrupted precipitation patterns and increased CO2 levels that are associated with future climate conditions are expected to impact the growth and toxigenic potential ofA. flavus. Both laboratory and real world observations have demonstrated this potential, especially when examining the effects of water availability and temperature. Recent experiments have also established that CO2 may also be affecting toxin production. The application of current technologies in the field of functional genomics, including genomic sequencing, RNA-seq, microarray technologies and proteomics have revealed climate change-related, abiotic regulation of the aflatoxin cluster and influence on the plant-fungus interaction. Furthermore, elevated CO2 levels have been shown to impact expression of the aflatoxin biosynthetic regulatory geneaflR. The use of functional genomics will allow researchers to better understand the underlying transcriptomic response within the fungus to climate change, with a view towards predicting changes in fungal infection and toxin production associated with climate change.

The ability of fungal plant pathogens to exude bioactive compounds is an important element of competition in a changing environment. The filamentous fungi usually retain a number of adaptations related not only to the production of toxic compounds by themselves but also to the mitigation of exogenous influences by toxins present in the environment. We examined a distinct effect of toxins on morphology, growth patterns and gene expression after stimulation in mycotoxin-producing and nonproducing isolates representing four evolutionarily divergent species (and chemotypes) within theFusarium genus (Fusarium graminearum,Fusarium oxysporum,Fusarium proliferatum andFusarium verticillioides). The aim of our work was to investigate the influence of mycotoxins present in the environment on fungal isolates belonging to evolutionarily divergent complexes withinFusarium genus. The results point to retention of resistance mechanisms in non-producer isolates (F. oxysporum) and specific dose-dependent differences in response to other mycotoxins. In particular, the growth ofFusarium graminearum (confirmed zearalenone and trichothecene producer) was shown to be significantly inhibited by fumonisin B1 and deoxynivalenol. Conversely, spread ofFusarium verticillioides was accelerated by low concentrations (0.5 mg/l) of nivalenol and zearalenone and deoxynivalenol addition resulted in upregulation of the fumonisin poliketyde synthase (FUM1). The basics of competition between divergent fusaria can be described by ‘rock-paper-scissors’ theory, but some of the effects can be explained by other interactions, e.g. autotoxicity of deoxynivalenol and the potential role of low doses of trichothecenes and zearalenone acting as a ‘warning signal’ for competing species.

The aim of this work was to assess the inhibitory effect of essential oils on the growth and aflatoxin production ofAspergillus parasiticus, as well as to correlate it with the chemical composition of the essential oils. Essential oils from six aromatic species (Cymbopogon citratus,Eucalyptus globulus,Origanum vulgare,Ruta graveolens,Salvia officinalis, Satureja montana) were characterised by gas chromatography and tested for their inhibitory effect againstA. parasiticus strain MUM 92.02. Furthermore, thein vitro inhibitory effects of these essential oils on the production of aflatoxins were evaluated by HPLC. Results showed that all essential oils retarded the time for visible growth. Growth rate was affected differently depending on the essential oil.S. montana essential oil prevented growth in all cases. The essential oil ofR. graveolens inhibited most of the aflatoxin production even though growth inhibition was low, while withC. citratus essential oil trace levels of aflatoxins were detected. Essential oils containing carvacrol and/or thymol (S. montana andO. vulgare) have the highest activity against fungal growth, while an essential oil (R. graveolens) containing 2-undecanone and 8-phenyl-2-octanone inhibited the synthesis of aflatoxins. Although the main component of this essential oil was 2-undecanone (91%), when pure 2-undecanone was tested, it did not inhibit aflatoxin production. Inhibition activity is probably due to the recently identified minor compound or to a synergistic effect. Essential oils seem to be a good alternative to fungicides not only because of environmental issues but also because they do not seem to enhance mycotoxin production as it has been reported for some fungicides.

In this study, the effects of pure olive phenolic compounds and olive mill wastewater (OMWW) (after membrane filtration treatments) onAspergillus flavus growth and aflatoxin B1 (AFB1) production, were investigated. Five OMWWs coming from Greek (Lianolia, Koroneiki andAsprolia) and Italian (Cellina di Nardò andCoratina) olive oil cultivars, opportunely filtered using a membrane system, were added at two concentrations (5 and 15%) to growth medium, in order to evaluate their effect onA. flavus growth and AFB1 production. The OMWW fractions treatment, after 6 days of incubation, did not inhibit the fungal growth rate, but at 15% concentration significantly reduced the AFB1 production (ranging from 88 to 100%). A similar approach was used for caffeic acid, hydroxytyrosol, tyrosol and verbascoside, the major pure phenolic compounds identified in OMWW fractions. They were evaluated at increasing doses (10, 50 and 100 µg/ml) following both AFB1 production and fungal growth. At the highest concentration (100 µg/ml) all pure compounds showed a reduction of about 99% of AFB1 production without any influence on fungal growth. This is the first time in which OMWWs and their main phenolics were used in the treatments against AFB1 production. The results obtained could provide possible new strategies for preventing AFB1 food contamination using olive polyphenols and OMWW fractions with anti-aflatoxigenic effect, and permitting to harness in a sustainable way an olive oil by-product.

Selected resorcylic acid lactones (RALs) – zearalenone (ZEA), α-zearalanol (α-ZAL), β-zearalanol (β-ZAL), α-zearalenol (α-ZOL) and β-zearalenol (β-ZOL) were investigated for their oestrogenic and (anti)androgenic activity using twoin vitro RIKILT yeast Estrogen and Androgen bioAssays. Our results show that all tested compounds are able to induce hERα-dependent transcription and the rank of their potencies, based on EC50 values is as follows: α-ZOL > α-ZAL > ZEA > β-ZAL > β-ZOL. None of the tested compounds appeared to be androgenic when tested individually at concentrations ranging from 0.1 pM to 0.1 mM. However, all RALs inhibited 17β-testosterone-induced transcriptional activity. The highest antiandrogenic potential showed α-ZOL, β-ZAL and β-ZOL with the IC50 of 6.2 μM, 11.5 μM and 15.2 μM, respectively. When compared with flutamide, for which a relative antiandrogenic potency (RAAP) was assumed as 100%, the corresponding RAAPs for α-ZOL, β-ZAL and β-ZOL were 220, 119 and 89.8%, respectively. In summary, our study revealed that RALs possess not only oestrogenic, but also antiandrogenic activity. Further research is warranted to clarify the role of disruption of androgen receptor signalling in humans and animals.

Cytokines are proteins secreted by cells of innate and acquired immunity, produced in response to various antigens and responsible for mediating several function of these cells. Our study evaluated the profile of cytokines interleukin 5 (IL-5) and interferon gamma (IFN-γ), induced in lymphocytes of broiler chickens in response to secondary fungal metabolites ochratoxin A (OTA) and deoxynivalenol (DON) at concentrations of 0.001, 0.01, 0.1 and 1 μg/ml. The quantification of the cytokines was analysed at 24, 48 and 72 h after incubation with mycotoxins, using real-time PCR (qRT-PCR). The results obtained showed that OTA induced mRNA synthesis of IL-5 at concentrations 0.001, 0.1 and 1 μg/ml after 24 h of lymphocyte incubation, while at 48 h only the expression of the IL-5 cytokine at a concentration of 1 μg/ml (P<0.05) was detected. DON in a concentration of 1 μg/ml induced the expression of IL-5 in the lymphocytes only at 48 h post-incubation period (P<0.05). Regarding IFN-γ, gene expression was not observed in the lymphocytes of broiler chickens incubated with OTA and DON. The data obtained represent a profile of response mediated by T helper 2 cells to the exposure of broiler chicken immune cells to different concentrations of OTA and DON.

Fusarium head blight (FHB) or scab, caused byFusarium graminearum, is a highly destructive disease of wheat that can affect wheat grain yield and quality and contaminate grains and grain products with trichothecene mycotoxins, such as deoxynivalenol (DON). The purpose this study was to evaluate FHB resistance and DON accumulation in whole grain flour (WGF) and patent flour (PF) from different wheat genotypes developed for the humid subtropical conditions in southern Brazil. Three types of physiological resistance were evaluated: resistance against initial infection, resistance to kernel infection, and resistance to DON accumulation, known as the type I, III and V resistance reactions to FHB, respectively. The experimental design was factorial, and the factors studied were genotypes (n=23), type of flour (WGF and PF), inoculation (uninoculated or inoculated), and growing season (2011 and 2012). The genotypes were screened with natural infection and were artificially inoculated by spraying a conidial suspension at mid-anthesis. DON content in WGF and PF was significantly affected by all the tested sources of variation and their interactions. Averaged among genotypes, the increase in DON content in WGF compared with PF was 29.3%, ranging from 1.7 to 66.4%. Significant differences in FHB incidence and severity,Fusarium-damaged kernels, yield and test weight (Tw) were observed among wheat genotypes. Artificial inoculation significantly affected the DON content of WGF and PF but not the other variables, indicating its utility in southern Brazil. Linear correlations between DON accumulation in WGF or PF and resistance to FHB variables, yield and Tw were also determined.

In a mycotoxin-dedicated total diet study (mTDS) performed in the autumn and winter of 2013 in the Netherlands, 48 mycotoxins, including patulin, aflatoxins, ochratoxin A, fumonisins, zearalenone, trichothecenes, ergot alkaloids,Alternaria toxins, beauvericin and enniatins, were quantified. Analyses were performed in 88 composite samples representative for the consumption pattern of the Dutch population. This article presents the results of the exposure assessment and subsequent risk assessment of these mycotoxins. Exposure was assessed by combining individual food consumption data obtained from the Dutch National Food Consumption Surveys (DNFCS) for young children aged 2-6 years and the population aged 7-69 years with the analytical results of the mTDS, using a lower bound and an upper bound scenario for levels below the limit of detection. Wherever possible, exposure estimates were compared with toxicological reference values, including health-based guidance values. The high level of exposure (95th percentile) exceeded the toxicological reference value regardless of the substitution scenario for ochratoxin A in the population aged 7-69 years, for the sum of T-2 and HT-2 toxins for children aged 2-6 years and for alternariol and alternariol monomethyl ether in both examined populations. The margin of exposure was too small for aflatoxin B1. For the remaining 23 mycotoxins with a toxicological reference value, the estimated exposure was below this level.

The metabolism of theAlternaria toxins alternariol (AOH), alternariol-9-O-methyl ether (AME) and altenuene (ALT) by the microbiota present in faeces from three human volunteers was studied. Faecal cultures were prepared as a 5% faeces suspension in brain-heart infusion broth and incubated with 50 μM of the toxins under anaerobic conditions for 72 h at 37 °C. The metabolism of AOH was also studied in pure bacterial cultures with eitherEscherichia coli DH5α orLactobacillus plantarum BFE 5092 for 72 h at 37 °C. The three parent toxins were stable in uninoculated, heat-treated medium over a 72 h incubation period with a recovery of more than 90%. As a control for the activity of the faecal microbiota, the isoflavone daidzein was incubated with the faecal cultures and was transformed to its expected metabolites. In contrast, no metabolites of AOH, AME and ALT could be detected in the faecal cultures from the same volunteers, indicating that the gut microbiota was not capable of metabolising these substances. TheAlternaria toxins could be shown to be at least partially bound to bacterial cells in a non-covalent manner, which may serve as a mechanism for their removal from the gut.