Search

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., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Bacillus-based biocontrol agents have emerged as a strategy to eliminate or reduce the use of synthetic fungicides that are detrimental to health and the environment. In vineyards, a special concern arises from the control of Aspergillus carbonarius, a fungus known for its potential to produce ochratoxins. Ochratoxin A (OTA) is the most toxic form among ochratoxins and its maximum limit in wine has been established in Europe and Brazil as 2 μg/kg. Wine quality, especially the volatile profile, may be influenced by the antifungal strategies, since fungicide residues are transferred from grapes to must during winemaking. The objective of this study was to evaluate, for the first time, the impact of a biocontrol strategy containing Bacillus velezensis P1 on the volatile profile and occurrence of ochratoxins when grapes infected with A. carbonarius were used in winemaking. The evaluation of ochratoxins was carried out by liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (LC-QToF-MS), and volatile compounds were analyzed using comprehensive two-dimensional gas chromatography coupled to quadrupole mass spectrometry (GC × GC/qMS). Six ochratoxins were identified in must prepared with Chardonnay grapes inoculated with A. carbonarius (ochratoxin α, ochratoxin β, ochratoxin α methyl-ester, ochratoxin α amide, N-formyl-ochratoxin α amide and OTA). Although winemaking causes a decrease in the levels of all forms of ochratoxins, the co-occurrence of these mycotoxins was verified in wine made with grapes containing A. carbonarius. B. velezensis P1 prevented the occurrence of ochratoxins in must, ensuring the safety of wines. Regarding the volatile profile, a predominant presence of terpenic compounds was verified in samples treated with B. velezensis when compared with those not treated with the biocontrol strategy, whereas the presence of A. carbonarius resulted in a higher concentration of volatile compounds with an odor described as fatty/waxy, possibly compromising wine quality. Therefore, B. velezensis P1 is a new biofungicide possibility to produce ochratoxin-free grapes and high-quality wines., Competing Interests: Declaration of competing interest The authors declare no conflicts of interests., (Copyright © 2023. Published by Elsevier B.V.)

The main filamentous fungi producers of mycotoxins are Aspergillus spp., Penicillium spp., and Fusarium spp. Their effect can provoke a broad range of toxic properties including carcinogenicity and neurotoxicity, as well as reproductive and developmental toxicities. Ochratoxin A (OTA) is produced by Aspergillus and Penicillium spp. The purpose of this review was to evaluate the risk assessment of OTA in alcoholic drinks (beer and wine) by compiling the results obtained from studies and reviews related to the presence of OTA in these two drinks from southern European countries in the period 2005-2013 and comparing those results with the legislation available in the European Union.

Mycotoxins are secondary metabolites produced by fungi especially those belonging to the genus Aspergillus, Penicillum and Fusarium. Mycotoxin contamination can occur in all agricultural commodities in the field and/or during storage, if conditions are favourable to fungal growth. Regarding animal feed, five mycotoxins (aflatoxins, deoxynivalenol, zearalenone, fumonisins and ochratoxin A) are covered by EU legislation (regulation or recommendation). Transgressions of these limits are rarely observed in official monitoring programs. However, low level contamination by Fusarium toxins is very common (e.g., deoxynivalenol (DON) is typically found in more than 50% of the samples) and co-contamination is frequently observed. Multi-mycotoxin studies reported 75%-100% of the samples to contain more than one mycotoxin which could impact animal health at already low doses. Co-occurrence of mycotoxins is likely to arise for at least three different reasons (i) most fungi are able to simultaneously produce a number of mycotoxins, (ii) commodities can be contaminated by several fungi, and (iii) completed feed is made from various commodities. In the present paper, we reviewed the data published since 2004 concerning the contamination of animal feed with single or combinations of mycotoxins and highlighted the occurrence of these co-contaminations.

Ochratoxins have been overshadowed by better-known mycotoxins, but they are gaining importance. Here we consider ochratoxins in the context of aflatoxins, which are better understood than ochratoxins on many levels. We review recent work on taxonomic distribution, contamination of commodities, biosynthesis, toxicity and regulatory aspects of ochratoxins. We focus on ochratoxins in coffee, since coffee is becoming a key commodity in ochratoxin research and regulation.

In order to characterize by molecular methods the Aspergillus niger aggregate species involved in the ochratoxin A (OTA) contamination of European wine grapes and table grapes from Israel, a total of 173 strains were studied. The ITS-5.8S rDNA fragments of 173 A. niger agreggate strains from grapes included in this study were amplified and their PCR amplicons were RsaI digested in order to classify the strains in the RFLP types, N and T. All of the strains belonging to the A. niger aggregate were classified into the two RFLP types previously defined: type N (43%) and type T (57%). Twenty out of the 173 strains of A. niger aggregate produced OTA (0.1 to 10.5 mug g(-1)). All the OTA producing species belonged to the N-RFLP type.

Aims: To model the probability of exceeding the European legislative limit of 5 microg ochratoxin A (OTA) per kilogram grain in relation to Penicillium verrucosum levels and storage conditions, and to evaluate the possibilities of using P. verrucosum colony counts for predicting noncompliant OTA levels., Methods and Results: Cereal samples were inoculated with P. verrucosum spores and stored for up to 9 months at temperatures and water activities ranging from 10-25 degrees C and aw 0.77-0.95. A logistic regression analysis showed that the probability of exceeding 5 microg OTA kg(-1) grain was related to colony counts of P. verrucosum and water activity. The sensitivity and specificity of various P. verrucosum count thresholds for predicting noncompliant OTA levels were estimated, using data from the storage trial and natural cereal samples., Conclusion: The risk of exceeding 5 microg OTA kg(-1) grain increased with increasing levels of P. verrucosum, and with increasing water activities. A threshold of 1000 CFU P. verrucosum per gram grain is suggested to predict whether or not the legislative limit is exceeded., Significance and Impact of the Study: This study has provided a tool to evaluate the levels of P. verrucosum in grain in relation to OTA levels. Hence, mycological analyses can be used to identify cereal samples with high risk of containing OTA levels above the legislative limit., (Copyright 2004 The Society for Applied Microbiology)

Samples (633) of final coffee products were drawn from the markets of different European countries relative to the market share of each product type and brand. These samples were analysed in a cooperative action with nine different laboratories. With low limits of detection (mean detection limit approximately 0.5 ng/g) no OTA was found in over half of the samples (334 negatives). In the remaining samples occurrence of OTA at a rather low level was seen. Only four samples (all instants) exceeded a level of 10 ng/g, whereas for both instants, and roast and grounds (R & G), over three-quarters of the samples were in the range from nondetectable to 1 ng/g. The overall mean for all R & Gs was 0.8 ng/g and for all instant 1.3 ng/g (for samples in which no OTA was detected, half of the detection limit was included in this calculation). In the brewing methods frequently used in Europe the OTA is essentially fully extracted. Consumption of four cups of coffee per day (approximately 24 g R & G or approximately 8 g instant coffee) contributes on average 19 or 10 ng/day respectively. Four cups/day is above the per caput consumption level in most European contries. Compared with the Provisional Tolerable Weekly Intake (PTWI) recently set by the Joint FAO/WHO Expert Committee on Food Additives at 100 ng/kg bodyweight/week, consumption of 28 cups/week contributes up to 2% to the PTWI.

Numerous surveys conducted in North America, Asia and Europe have revealed that ochratoxin A is a natural contaminant of plant products. Contamination frequencies of up to 40% have been encountered, at levels in the range of 5-500 micrograms/kg. Ochratoxin A is a major causal determinant of the disease porcine nephropathy; but other nephrotoxic mycotoxins, such as citrinin and the fungal quinones, may be involved. The disease is characterized clinically by polyuria and growth depression. Renal lesions in pigs include degeneration of the proximal tubules, interstitial fibrosis and hyalinization of the glomeruli. The disease is endemic, outbreaks being associated with bad weather conditions. A positive correlation has been observed between the prevalence rates of porcine nephropathy and the frequency of ochratoxin A in corresponding feed samples. Surveys for residues of ochratoxin A in kidneys from cases of porcine nephropathy in a number of European countries other than Denmark have demonstrated that 21-42% of samples contain ochratoxin A in the range of 1-100 micrograms/kg.

Ochratoxin A is a mycotoxin produced by fungi occurring frequently on cereals. Their growth, and the associated toxin production, are closely correlated to the degree of moisture to which they are exposed, which itself is dependent on weather conditions at harvest and techniques for drying and storage. Eighteen species of fungi found in foods can produce ochratoxin A; all of these also produce other mycotoxins. The distribution of these mycotoxins in foods, which probably differs according to climate, has not yet been studied. The lowest doses of ochratoxin A that are toxic in experimental animals are four to five times higher than those found even in hyperendemic regions. This finding casts doubt on the hypothesis that ochratoxin A is the sole cause of Balkan endemic nephropathy and renal tumours. It is therefore not possible to estimate the risk from this mycotoxin for Europe or for individual European countries. Data on the occurrence of both ochratoxin A and other toxins and on the quantities consumed should be collected systematically; these can then be used to assess post-harvest techniques.

Currently, some 60 countries have enacted or proposed regulations for levels of mycotoxins in food and animal feed. Various factors may influence the establishment of tolerances for certain mycotoxins, such as the availability of data on dietary exposure and on toxicology, the distribution of the mycotoxins over commodities, the availability of analytical methodology, legislation in countries with which trading occurs and a sufficient food supply. Most of the existing regulations for mycotoxins concern aflatoxins, but the number of countries that regulate other mycotoxins as well is growing. Of the nephrotoxic mycotoxins, ochratoxin A was the only one for which regulations existed in 1990. At least 11 countries have proposed or official limits for ochratoxin A. The acceptable levels range from 1 to 50 micrograms/kg for food and from 100 to 1000 micrograms/kg for animal feed. The scientific basis for the established regulations appears to be weak, and a rationalization of tolerance levels for ochratoxin A would be highly desirable.

Ochratoxin A is a mycotoxin which contaminates cereals in particular and occurs all over the world. Humans are undoubtedly exposed to this toxin through foods of vegetable and animal origin and through airborne dust. The presence of ochratoxin A in human blood has been suggested as an indicator for indirect assessment of exposure to this nephrotoxic agent. In several countries, therefore, human blood has been collected with the purpose of obtaining more information on the intake of ochratoxin A. Analyses of serum samples in European countries revealed that blood from healthy humans was contaminated with ochratoxin A at concentrations of 0.1-14.4 micrograms/l. The frequency of contamination of human sera seems to indicate continuous, widespread exposure of humans to ochratoxin A.