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Maize is one of the most important crops cultivated worldwide, whose production can be affected by the presence of several pathogens. Fusarium verticillioides and Fusarium graminearum are the most predominant pathogens affecting maize ears. However, few studies have been focused on studying the interaction between both pathogens in field conditions. For this reason, the aim of the present work was to evaluate the interaction between F. graminearum and F. verticillioides in different genotypes of maize under field conditions. Field experiments were carried out during two growing seasons in Azul, Argentina, including 12 commercial hybrids of maize, which were inoculated with F. graminearum, F. verticillioides, and a mixture of both pathogens. Phenotypic traits (plant height, plant diameter, tiller and cob number, and radiation interception), disease evaluation, and mycotoxin contamination were analyzed. The results showed significant differences between genotypes in disease severity (DS) for both years. In general terms, higher values of DS were reported in 2020 (21.70% ± 0.40) than in 2021 (16.50% ± 0.20). Different climatic conditions registered along the assay, especially precipitations and relative humidity, could be responsible for the differences observed over the years. Moreover, no significant correlations were found regarding DS and mycotoxin contamination for each genotype. For these reasons, an automatic correspondence between DS and mycotoxin contamination could lead to wrong agronomic decisions. The present study points out novel information regarding plant-pathogen interaction (maize-F. verticillioides/F. graminearum) under field conditions that could be useful for future maize breeding programmes., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

Maize is one of the most important crops worldwide, being affected by several fungal species under field conditions. The study of plant-pathogen interaction plays a key role because fungal diseases are responsible for reducing grain yield and quality by increasing mycotoxin production. Thus, the present work aimed to evaluate the interaction of F. graminearum and F. verticillioides and mycotoxin production under field conditions along different physiological stages. During the 2019/2020 and 2020/2021 growing seasons, twelve maize genotypes were inoculated at the flowering stage (silking). Four treatments were applied using one isolate of each species: (i) F. graminearum; (ii) F. verticillioides; (iii) a combined inoculum (F. graminearum + F. verticillioides); (iv) and control treatment. Fungal diversity, disease evaluation, and mycotoxin contamination were evaluated at three different physiological stages: T1 (from R2 to R4), T2 (from R4 to R6), and T3 (at harvest time). A total of 15,907 Fusarium isolates were obtained. The results showed a predominance of F. verticillioides over F. graminearum in both years evaluated, reporting an increase in the occurrence of this species at late stages. Regarding mycotoxin contamination, no evidence was found supporting antagonism or synergism regarding isolates of both species used as inoculum under field conditions. The results reported in the present manuscript point out a major influence of climatic conditions on F. verticillioides predominance over F. graminearum, mainly during the late physiological stages. Furthermore, no clear relationship between mycotoxin concentration and physiological stages was established, suggesting that other grain factors, such as water activity and pH, could modulate mycotoxin production and accumulation under field conditions., 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 © 2023 Elsevier B.V. All rights reserved.)

Aims: The aims of this study were to determine the occurrence of Fusarium graminearum species complex (FGSC) on soybean pods, seeds and roots, including rhizoplane, during the period of soybean crop in rotation with wheat and to evaluate the FGSC dynamics on wheat and soybean residues during two soybean growing seasons in rotation with wheat, particularly F. graminearum sensu stricto (FGss)., Methods and Results: Soybean roots, pods and seeds were analysed during 2012/13 and 2013/14 seasons. The morphological identification of FGSC and mycotoxin analysis was done. Crop residues were taken in both soybean season in wheat rotation and FGss were quantificated by real-time PCR. The results showed that Fusarium species, mainly FGSC, survive in a soybean crop in rotation with wheat. Isolation frequency of these species was higher on soybean pods than on seeds at R6 stage. Deoxynivalenol contamination on soybean seeds was higher in the 2013/14 season in comparison with the 2012/13 season. Low isolation levels of Fusarium species and species that did not belong to FGSC were observed in soybean root, whereas in rhizoplane a higher level was observed. Fusarium species inoculum on residues remained stable during crop succession and the FGSC were recovered from both wheat and soybean residues. Real time PCR data showed a higher DNA concentration of FGss in wheat residues in the first developmental stages of soybean plants, being the levels more significant during 2012/13 season. With regard to soybean residues collected during the wheat growing stages, an increase in DNA from anthesis until wheat harvest was observed., Conclusions: In a no-till production system, the populations of FGSC can colonize wheat and soybean residues to become an inoculum source., Significance and Impact of the Study: This study provides new data on the occurrence of FGSC populations in soybean plant and FGss on residues in soybean-wheat rotation, a cultural practice commonly used in in Argentina., (© 2020 The Society for Applied Microbiology.)

This study examined the effect of interacting conditions of water activity (a W , 0.995, 0.98 and 0.95) and temperature (15, 25 and 30 °C) on growth rate of two Fusarium thapsinum and one F. andiyazi strains isolated from sorghum in Argentina. In addition, the effect of interacting conditions (a W  × temperature × incubation time (7, 14, 21 and 28 days)) on mycotoxin production (moniliformin (MON), fusaric acid (FA) and fusarin C (FUS C)) on a sorghum grain substrate was evaluated. Statistical analysis showed that a W and temperature significantly affected growth of both species, mainly the a W . Incubation time significantly influenced mycotoxin production by both species as well, mostly for FA. Maximum growth rates of the F. thapsinum strains were obtained at the highest a W (0.995) and 25 °C and growth rate decreased as a W and temperature were reduced. The same growth profile was observed for F. andiyazi RCFA09 (maximum growth rates at 0.995-25 °C). Mycotoxin production by both species was detected at the highest a W levels whereas at 0.95 a W only low amounts of MON were produced by F. thapsinum. Maximum MON and FUS C production by both F. thapsinum strains was observed at 0.995 a W and 25-30 °C after 28 days of incubation. Also, F. thapsinum strains showed maximum FA production at the highest a W and temperature but after 14 days; after this incubation time toxin levels significantly decreased. The responses to a W and temperature of F. andiyazi were similar to that of F. thapsinum strains in relation to FA and FUS C production. Maximum levels of FA were detected at the highest a W after 14 days of incubation at 25-30 °C. Fusarin C was produced at all assayed temperatures but maximum levels were detected at 30 °C and 0.995 a W after 28 days of incubation. Two-dimensional profiles on the interactions of a W by temperature were developed from these data to identify conditions that indicate a significant risk from MON, FA and FUS C accumulation on sorghum grains. The results of this study suggest that sorghum grains could be colonized by these species and toxin production can occur, especially during development stages under field conditions at high water activity of grains or during grain storage if the drying process is slow or deficient. To our knowledge, this study described for the first time FUS C production by F. thapsinum and F. andiyazi under interacting conditions of a W , temperature and incubation time on sorghum grains., Competing Interests: Declaration of competing interest None., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Barley (Hordeum vulgare L.) is one of the most important cereals worldwide, and its quality is affected by fungal contamination such as species of the genus Alternaria. No information is available about the occurrence of Alternaria mycotoxins in Argentinean barley grains, which is of concern, because they can be transferred into malt and beer. The aim of this study was to analyze the occurrence of alternariol (AOH), alternariol monomethyl ether (AME) and tenuazonic acid (TeA) in malting barley grains from the main producing region of Argentina during the 2014 and 2015 growing seasons., Results: The most frequent mycotoxin was AOH (64%), which was detected at higher levels (712 μg kg -1 ) compared with other studies, followed by TeA (37%, 1522 μg kg -1 ), while AME was present in five samples in the 2015 growing season only, with a mean of 4876 μg kg -1 . A similar frequency of mycotoxin occurrence was observed in both years (80.8 vs 85.3%), but more diverse contamination was found in 2015, which was characterized by lower accumulated precipitation. Nevertheless, AOH was more frequently found in 2014 than in 2015 (80.8 and 47.1% respectively). A negative correlation between AOH concentration and temperature was observed. The susceptibility of different barley varieties to mycotoxin accumulation varied with the mycotoxin, geographical location and meteorological conditions., Conclusion: The results obtained in the present work represent a tool for risk assessment of exposition to these mycotoxins and could be used by food safety authorities to determine the need for their regulation. Furthermore, the establishment of a hazard analysis and critical control point (HACCP) system to minimize fungal and mycotoxin contamination in barley from farm to processing could be apply to ensure food safety. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

Alternaria species have been reported to infect a wide variety of vegetables, fruits, and cereal crops. Wheat is one of the most consumed cereal worldwide. A sensitive HPLC-DAD methodology was applied to quantify alternariol (AOH), alternariol methyl ether (AME) and tenuazonic acid (TeA) in 65 samples of whole wheat, bran, and flour. The extraction methodology allowed extracting the three toxins simultaneously. Limits of detection in wheat were 3.4, 4.5, and 0.5 µg kg -1 for AOH, AME and TeA, respectively. For bran, these data were 3.1, 4.5, and 12 µg kg -1 and for flour 50, 70, and 14 µg kg -1 , respectively. The studied recoveries were higher than 70% and RSD was below 10%. Wheat and bran samples showed low AOH and AME contamination compared to TeA. The averages levels found for TeA in wheat, bran and flour were 19,190, 16,760, and 7360 µg kg -1 , respectively.

The group of the small-spored Alternaria species is particularly relevant in foods due to its high frequency and wide distribution in different crops. These species are responsible for the accumulation of mycotoxins and bioactive secondary metabolites in food. The taxonomy of the genus has been recently revised with particular attention on them; several morphospecies within this group cannot be segregated by phylogenetic methods, and the most recent classifications proposed to elevate several phylogenetic species-groups to the taxonomic status of section. The purpose of the present study was to compare the new taxonomic revisions in Alternaria with secondary metabolite profiles with special focus on sections Alternaria and Infectoriae and food safety. A total of 360 small-spored Alternaria isolates from Argentinean food crops (tomato fruit, pepper fruit, blueberry, apple, wheat grain, walnut, pear, and plum) was morphologically identified to species-group according to Simmons (2007), and their secondary metabolite profile was determined. The isolates belonged to A. infectoria sp.-grp. (19), A. tenuissima sp.-grp. (262), A. arborescens sp.-grp. (40), and A. alternata sp.-grp. (7); 32 isolates, presenting characteristics overlapping between the last three groups, were classified as Alternaria sp. A high chemical diversity was observed; 78 different metabolites were detected, 31 of them of known chemical structure. The isolates from A. infectoria sp.-grp. (=Alternaria section Infectoriae) presented a specific secondary metabolite profile, different from the other species-groups. Infectopyrones, novae-zelandins and phomapyrones were the most frequent metabolites produced by section Infectoriae. Altertoxin-I and alterperylenol were the only compounds that these isolates produced in common with members of section Alternaria. None of the well-known Alternaria toxins, considered relevant in foods, namely alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), tentoxin (TEN) or altenuene (ALT), were produced by isolates of this section. On the other hand, strains from section Alternaria (A. tenuissima, A. arborescens, and A. alternata sp.-grps.) shared a common metabolite profile, indistinguishable from each other. AOH, AME, ALT, TEN, and TeA were the most frequently mycotoxins produced, together with pyrenochaetic acid A and altechromone A. Alternaria section Alternaria represents a substantial risk in food, since their members in all types of crops are able to produce the toxic metabolites., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: A survey on Fusarium species and moniliformin (MON) occurrence in sorghum grains collected from one of the main sorghum-producing areas of Argentina was conducted. Also, growth of F. thapsinum, one of the main sorghum pathogens, and MON production under different water activity (a w ) conditions on a sorghum-based medium were determined., Results: Infection of sorghum grains by Fusarium species ranged from 82.5 to 99%; closely related species F. verticillioides, F. thapsinum and F. andiyazi were the most frequently recovered, followed by F. proliferatum and F. subglutinans. By sequencing a portion of the translation elongation factor-1α (TEF-1α) gene and by maximum parsimony analysis, F. verticillioides and closely related species were identified as F. thapsinum, F. andiyazi and F. verticillioides. Species within the F. graminearum species complex (FGSC) were isolated in high frequency. Maximum growth rates of 12 F. thapsinum strains were obtained at 0.995 a w . All evaluated strains were able to produce MON at all a w values tested, but MON production was higher at 0.995-0.982 a w . MON was detected in 41% of the samples at levels ranging from 363.2 to 914.2 µg kg -1 ., Conclusion: This study provides new data on the occurrence of Fusarium species in sorghum grains destined for animal consumption in Argentina. The production of MON at different a w values showed that the toxin can be produced under field conditions. The risk to livestock exposed to daily low levels of MON associated with the toxin occurrence in the sorghum grains analyzed is unknown. © 2018 Society of Chemical Industry., (© 2018 Society of Chemical Industry.)

Background: The assessment of ochratoxin A (OTA) in wine is relevant for food safety and its continuous control allows to reduce the risk of intake. Thus, a novel sensitive QuEChERS-SPE (Quick, Easy, Cheap, Effective, Rugged and Safe - Solid Phase Extraction) pretreatment prior to liquid chromatography coupled to tandem mass spectrometry was developed for the determination of OTA in red wine samples from different grape-growing regions in Argentine., Results: A sensitive methodology was achieved and thus the limits of detection and quantification were 0.02 and 0.05 µg L -1 , respectively. Recoveries ranged from 89.0% to 105.3%. The method was applied to 136 red wine samples (Argentina's flagship varieties: Malbec and Cabernet Sauvignon) from ten grape-growing regions, during vintages 2013-2015. Although all of the samples investigated were contaminated with OTA (concentrations ranged from 0.02 to 0.98 µg L -1 ), the levels detected were lower than the maximum allowable concentration limit of 2.0 µg L -1 established by international regulations., Conclusion: The methodology proposed is suitable for reliable OTA analysis in red wines. Similarly, the values obtained from the samples analyzed were in accordance with the current regulations and, as a consequence, preventive actions to reduce this mycotoxin incidence can be undertaken. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

The aim of this study was to evaluate the occurrence of several fungal metabolites, including mycotoxins in natural grasses (Poaceae) intended for grazing cattle. A total number of 72 and 77 different metabolites were detected on 106 and 69 grass samples collected during 2011 and 2014, respectively. A total of 60 metabolites were found across both years. Among the few mycotoxins considered toxic for ruminants, no samples of natural grasses were contaminated with aflatoxins, ochratoxin A, ergot alkaloids, and gliotoxin, among others. However, we were able to detect important metabolites (toxic to ruminants) such as type A trichothecenes, mainly T-2 toxin and HT-2 toxin (up to 5000 µg/kg each), and zearalenone (up to 2000 µg/kg), all at very high frequencies and levels. Other fungal metabolites that were found to be prevalent were other Fusarium metabolites like beauvericin, equisetin and aurofusarin, metabolites produced by Alternaria spp., sterigmatocystin and its precursors and anthrachinone derivatives. It is important to point out that the profile of common metabolites was shared during both years of sampling, and also that the occurrence of important metabolites is not a sporadic event. Considering that this area of temperate grassland is used for grazing cattle all year long due to the richness in palatable grasses (Poaceae), the present work represents a starting point for further studies on the occurrence of multi-mycotoxins in natural grasses in order to have a complete picture of the extent of cattle exposure. Also, the present study shows that the presence of zeranol in urine of beef cattle may not be a consequence of illegal use of this banned substance, but the product of the natural occurrence of zearalenone and α-zearalenol in natural grasses intended for cattle feeding.

Mycotoxins including aflatoxins, deoxynivalenol, fumonisins and ochratoxin A are among the main fungal secondary metabolites detected as natural contaminants in South America in different commodities such as peanuts (aflatoxins), cereals (deoxynivalenol and fumonisins) or grapes (ochratoxin A). Different strategies including crop rotation, tillage practices, fungicide application and planting less susceptible cultivars are used in order to reduce the impact of these mycotoxins in both food and feed chains. The development of fungicide resistance in many fungal pathogens as well as rising of public concern on the risks associated with pesticide use led to the search for alternative environmentally friendly methods. Biological control of plant pathogens and toxigenic fungi offers an alternative that can complement chemical control in the frame of an integrated pest management to reduce the impact of mycotoxins in the food and feed chains. The advances made in Argentina on reducing the impact of toxigenic fungi and mycotoxins in peanut, grapes and cereals using the biocontrol strategy are summarised. Native bacteria, yeasts and filamentous fungi have been selected to evaluate them as potential biocontrol agents. Field trials showed that Bacillus subtilis RC 218 and Brevibacillus sp. RC 263 were effective at reducing deoxynivalenol accumulation in wheat. The application of Clonostachys rosea isolates on wheat stubble reduced Fusarium colonisation on the stubble. Bacillus amyloliquefaciens and Microbacterium oleovorans showed good activity to control both Fusarium verticillioides growth and the accumulation of fumonisins at pre-harvest stage in maize. Control of toxigenic Aspergillus flavus and aflatoxin accumulation in peanuts was achieved using a native atoxigenic Aspergillus flavus strain based on competitive exclusion of the toxigenic strains. Kluyveromyces thermotolerans strains were used as biocontrol agents to reduce the impact of Aspergillus section Nigri and ochratoxin A accumulation in grapes.

Fusarium graminearum is one of the most important pathogens isolated from small cereal grains with Fusarium Head Blight symptoms. The presence of this fungus is often linked to the occurrence of several mycotoxins in barley and wheat. The aim of our study was to characterize trichothecene genotypes and production profiles of F. graminearum sensu stricto isolates obtained from barley grains in Argentina. A total of 110 F. graminearum s.s. isolates were analyzed by PCR assays to predict deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-ADON), 3-acetyldeoxynivalenol (3-ADON) and nivalenol (NIV) production, and all isolates were found to belong to the same molecular 15-ADON genotype. Trichothecene production in autoclaved rice was analyzed by using gas chromatography (GC) and confirmed by GC-MS. Of the 110 isolates, 95% were able to produce DON, 71% produced 15-ADON, 63% 3-ADON and 52% NIV. With the exception of a single isolate, all isolates that produced NIV, also produced DON. However, the NIV production was very low, ranging from 0.13 to 0.30 μg/g. Six different production profiles of DON and its acetyl-derivatives were detected, the predominant being simultaneous production of DON, 3-ADON and 15-ADON, followed by DON production, and DON and 15-ADON co-production. This work is the first attempt to characterize the trichothecene genotypes and production profiles of F. graminearum s.s. isolates from Argentinean barley., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Many Alternaria species have been studied for their ability to produce bioactive secondary metabolites, such as tentoxin (TEN), some of which have toxic properties. The main food contaminant toxins are tenuazonic acid, alternariol (AOH), alternariol monomethyl ether (AME), altenuene, and altertoxins i, ii and iii., Aims: To determine the profiles of secondary metabolites characteristic of Alternaria strains isolated from tomato for their chemotaxonomic classification., Methods: The profiles of secondary metabolites were determined by HPLC MS., Results: The Alternaria isolates obtained from spoiled tomatoes belong, according to their morphological characteristics, to the species groups Alternaria alternata, Alternaria tenuissima and Alternaria arborescens, with A. tenuissima being the most frequent. The most frequent profiles of secondary metabolites belonging to the species groups A. alternata (AOH, AME, TEN), A. tenuissima (AOH, AME, TEN, tenuazonic acid) and A. arborescens (AOH, AME, TEN, tenuazonic acid) were determined, with some isolates of the latter being able to synthesize AAL toxins., Conclusions: Secondary metabolite profiles are a useful tool for the differentiation of small spored Alternaria isolates not easily identifiable by their morphological characteristics., (Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

Moulds are capable of reducing the nutritional value of feedstuff as well as elaborating several mycotoxins. Mycotoxin-contaminated feed has adverse effects on animal health and productivity. Also, mycotoxins may be carried over into meat and eggs when poultry are fed with contaminated feed. In a point prevalence study feedstuff used for poultry nutrition in Argentina was analyzed for fungal flora, natural incidence of selected mycotoxins, and nutritional quality. Ten mould genera were recovered, six of them known to be mycotoxigenic. More than 28 species were determined. Fumonisins were detected in all the samples (median 1,750 ppb). Forty-four out of 49 samples (90%) were contaminated with DON (median 222 ppb) and OTA (median 5 ppb). Also, 44 out of 49 samples were contaminated with aflatoxins (median 2.685 ppb), 42 samples (86%) with ZEA (median 50 ppb), and 38 samples (78%) with T2-toxin (median 50 ppb). Ninety percent of the samples had at least one type of nutritional deficiency. This study indicates the need for continuous assessment of the mycological status of animal feed production, in order to feed animals for optimal performance ensuring food safety.

A total of 89 freshly harvested soybean seed samples (Roundup Ready [transgenic] soybean cultivars) from the 2010/2011 crop season were collected from five locations in the Northern Pampean Region II, Argentina. These samples were analyzed for internal mycoflora, toxin production of isolated fungi, and for a range of mycotoxins. Mycotoxin analysis of aflatoxins (AFs), zearalenone (ZEA), fumonisins (FBs) and ochratoxin A (OTA) was done by HPLC-FLD (high performance liquid chromatography with postcolumn fluorescence derivatization), alternariol and alternariol monomethyl ether with HPLC-UV (HPLC with UV detection), trichothecenes (deoxynivalenol, nivalenol, T-2 toxin, HT-2 toxin, fusarenon X, 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol were analyzed by GC-ECD (gas chromatography with electron capture detector). Fungal colonization was more frequently found for samples from América, Saladillo and Trenque Lauquen than for samples from General Villegas and Trenel; a total of 1,401 fungal isolates were obtained from the soybean seeds. The most commonly identified fungal genera were Alternaria, Sclerotinia, Chaetomium, Cladosporium, Aspergillus, Penicillium, Phomopsis and Fusarium. Alternaria alternata, A.tenuissima, Aspergillus flavus, Penicillium citrinum, Fusarium verticillioides and F.semitectum were the predominant toxigenic fungal species. Mycotoxin production was confirmed for several isolates of toxigenic species, including Aspergillus flavus, A. parasiticus, Alternaria alternata, A.tenuissima, Fusarium graminearum, F semitectum and F. verticillioides. In particular, the percentage of mycotoxigenic Alternaria alternata (100%), A.tenuissima (95%) and aflatoxigenic strains of A. flavus (57%) were remarkably high. Although none of the mycotoxins, AFs, ZEA, FBs, trichothecenes and OTA, were directly detected in samples of soybean seeds, the frequent presence of toxigenic fungal species indicates the risk of multiple mycotoxin contamination.

In Facultad de Ciencias Exactas y Naturales,Universidad de Buenos Aires there is a service called Servicio de Identificación de Hongos Tóxicos, directed by researchers of the Program of Medicinal Plants and Fungi Involved in Biological Degradation (PROPLAME-PRHIDEB, CONICET) that assist hospitals and other health establishments, identifying the different samples of fungi and providing information about their toxicity, so that patients can receive the correct treatment. The objective of the present study was to analyze all the cases received from 1985 to 2012. This analysis permitted the confection of a table identifying the most common toxic species. The information gathered revealed that 47% of the patients were under 18 years of age and had eaten basidiomes; the remaining 53% were adults who insisted that they were able to distinguish edible from toxic mushrooms. Chlorophyllum molybdites turned out to be the main cause of fungal intoxication in Buenos Aires, which is commonly confused with Macrolepiota procera, an edible mushroom. In the second place Amanita phalloides was registered, an agaric known to cause severe symptoms after a long period of latency (6-10 hours), and which can lead to hepatic failure even requiring a transplant to prevent severe internal injuries or even death, is not early and correctly treated.

A total of 120 pelleted poultry feed samples from Entre Ríos Province, Argentina, were evaluated. The aims were to investigate (1) the presence of relevant toxigenic fungi, as well as to determine the ability to produce aflatoxins (AFs) by Aspergillus section Flavi isolated strains; and (2) the natural co-occurrence of AFs, fumonisins (FBs), gliotoxin, diacetoxyscirpenol (DAS), HT-2 and T-2 toxin by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Total fungal counts were below the established value (1 × 10⁴ CFU g⁻¹). Aspergillus flavus and A. parasiticus were the only aflatoxigenic species isolated. Co-occurrence of fumonisin B₁ (FB₁), HT-2 and T-2 toxin was detected in 100% of the feeds, with mean levels from 4502 to 5813; 6.7 to 21.6 and 19.6 to 30.3 µg kg⁻¹, respectively. A large number of starter samples were co-contaminated with aflatoxin B₁ (AFB₁), FB₁, HT-2 and T-2 toxins. Gliotoxin and DAS were not found in this survey.

The aims of the present work were: (1) to determine both mycobiota in raw materials and finisher poultry feed, as well as the ability to produce aflatoxin B1 by A. flavus strains, and (2) to evaluate the natural co-occurrence of aflatoxins (AFs), fumonisins (FBs), gliotoxin, diacetoxyscirpenol (DAS), HT-2 toxin, and T-2 toxin in poultry feed by LC-MS/MS. Nineteen percent of raw materials and 79% of finisher poultry feed samples exceeded the maximum allowed total fungal count (1 × 10(4) CFU g(-1)) to ensure hygienic quality. Aspergillus flavus was the only species belonging to section Flavi which was isolated while Fusarium verticilliodes was the prevalent species. Forty-seven percent of A. flavus strains were aflatoxin B1 producers and the highest frequency of aflatoxigenic strains was isolated from finisher poultry feeds. Principal component analysis showed that corn grains are closely related with total fungal and Fusarium counts. This positive relationship suggests that total fungal and Fusarium spp. counts in poultry feed might come mainly from corn grains. Regarding poultry feeds, in ground finisher type, Aspergillus spp. counts increased as water activity (aw) diminished. A positive relationship among aw, total fungal and Fusarium spp. counts was observed in both ground finisher and ground starter feed. Several mycotoxins were monitored in feeds by applying the LC MS/MS technique. One hundred percent of poultry samples were contaminated with FB1, and the highest levels were detected in pelleted finisher poultry. AFB1, gliotoxin, DAS, HT-2 toxin, and T-2 toxin were not detected in any poultry feed. The scarcity of available mycotoxicological studies from Argentinean poultry feed using a multitoxin analysis technique enhances the contribution of the findings of this report.

A stochastic simulation model was developed to carry out the first quantitative risk exposure assessment of the mycotoxin level in cow's milk produced in Argentina. The prevalence and concentration of aflatoxin M1 (AFM1), deoxynivalenol (DON) and zearalenone (ZEA) were modeled at various stages through milk processes complying with Argentinean practices. Concentration of AFM1 (0.059ppb), DON (0.338ppb) and ZEA (0.125ppb) in dairy milk were estimated. The proportion of feed samples that exceeded the maximum level accepted by European regulations for AFB1, DON and ZEA were estimated at 25.07%, 0.0% and 8.9%, respectively. The percentage of milk samples that exceeded the maximum level accepted for AFB1 by the MERCOSUR (0.5ppb) and the European Union regulations (0.05ppb) were 0.81 and 32.65, respectively. The probability distribution of AFM1 concentration in milk was affected by the carry-over rate equations applied in the model. Mycotoxin levels in corn silage and concentrated feeds were the factors most correlated with mycotoxin concentrations in milk. Therefore, agricultural practices, crop management and feed production require prompt attention regarding mycotoxin issues., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The objective of this investigation was to contribute towards the knowledge of microbiology of honey, more than 50 samples of honey from Slovakia and other countries were mycologically investigated in terms of the overall fungal diversity and toxicological potential of isolated fungi from Penicillium genera. The study revealed that out of 13 genera recovered, Penicillium was the most frequent and diverse genus, followed by Aspergillus and Cladosporium being found in 65.91 % (29 samples), 34.1 % (15 samples) and 29.55 % (13 samples), respectively. The most frequently encountered taxa from Penicillium genera were Penicillium chrysogenum (found in 22.73 %), Penicillium brevicompactum (13.64 %), Penicillium crustosum (11.36 %) and Penicillium griseofulvum (11.36 %). In addition, the following genera were recorded (in descending order) Mycelia (18.18 %), Fusarium (11.36 %), Mucor (9.09 %), Acremonium (6.82 %), Alternaria (4.55 %), Epicoccum (4.55 %), and finally Botrytis, Eurotium Trichoderma and Phoma all were encountered in 2.27 % of the samples being represented. The mean value counts of total fungi ranged from 0.00 to 2 × 10(2) cfu.g(-1). Outcomes from mycotoxin screening within the appropriate potentially toxinogenic species from Penicillium genera showed a number of mycotoxin producers, namely those forming citrinin (n = 1), cyclopiazonic acid (n = 5), griseofulvin (n = 5), patulin (n = 5), penitrem A (n = 2) and roquefortin C (n = 13).

In this study, ochratoxin A (OTA) occurrence in Argentinean musts, wines and dried vine fruits was evaluated, alongside with the performance of OchraStar(TM) columns for OTA extraction. In all the three matrices analyzed, the OchraStar(TM) columns showed good performance. The analysis of natural occurrence of OTA in the red must and the red wine samples showed low incidence with low levels of mean OTA contamination (0.12 ng/mL and 0.37 ng/mL, respectively), while 60% of the dried vine fruit samples were contaminated with OTA, in levels ranging from 0.26 to 20.28 ng/g.

Aims: To evaluate the mycobiota and natural levels of aflatoxins, fumonisins and zearalenone present in compound feed and home-corn grains intended for fattening pigs., Methods and Results: Total fungi, Fusarium and Aspergillus species occurrence were examined. Aflatoxins and zearalenone were detected by thin-layer chromatography and fumonisins by high-pressure liquid chromatography. Fungal counts were generally higher than 1 x 10(5) colony forming units (CFU) ml(-1). Aspergillus flavus, Aspergillus parasiticus and Fusarium verticillioides were the most prevalent species. FB(1) and FB(2) were detected in all feed and corn samples. Aflatoxin B(1) was detected in 33.33% of initial and growing feed and in 44.44% of final feed samples. It was not detected in corn samples. All feed and corn samples were negative for AFB(2), AFG(1), AFG(2) and ZEA presence during all growing stages tested., Conclusions: Fungal counts at all growing periods exceeded the levels proposed as feed hygienic quality limits. Aflatoxin levels in all feeds and fumonisin levels in many samples were higher than the established regulations., Significance and Impact of the Study: The presence of mycotoxins indicates the existence of contamination. This fact requires periodic monitoring to prevent the occurrence of mycotoxicosis in animal production, to reduce the economic losses and to minimize hazards to human health.

Aim: To determine fungal genera, Aspergillus and Fusarium species and aflatoxin B(1) (AFB(1)), zearalenone (ZEA), deoxynivalenol (DON), fumonisin B(1) (FB(1)) contamination from pre- and postfermented corn silage produced in the most important region of Argentina where silage practice is developed., Methods and Results: Sampling of corn silos was performed manually through silos in transects at three levels: upper, middle and low sections. AFB(1) and FB(1) were quantified by high-performance liquid chromatography, zearalenone by enzyme-linked immunosorbent assay and DON by gas chromatography. Over 90% of the samples showed counts higher than 1 x 10(4) CFU g(-1). Aspergillus flavus and Fusarium verticillioides were the prevalent species. Some tested samples were contaminated with AFB(1), ZEA, DON and FB(1)., Conclusions: This study demonstrates the presence of fungi and AFB(1), ZEA, DON and FB(1) contamination in corn silage in Argentina., Significance and Impact of the Study: This manuscript makes a contribution to the knowledge of mycotoxins in Argentinean silage in particular because the environmental conditions in this country differ from those of most reports. The comparison of pre- and postfermentation silage is also outstanding. Therefore, information on fungi and mycotoxins present in silage--an increasingly popular commodity--is useful to estimate potential risk for animal and human health.

To evaluate the potential for mycotoxin production by fungi in dried vine fruits, the mycobiota was determined both before and after surface disinfection. Predominant genera were Aspergillus (50.2%), Eurotium (21.4%) and Penicillium (13.5%). Aspergillus section Nigri ("black aspergilli") were isolated with relatively high frequency. Aspergillus niger was the most common species but only 3 of 293 isolates screened were ochratoxin A (OTA) producers. Aspergillus carbonarius was less common but 96% of 48 strains screened were ochratoxigenic. OTA was not produced by A. japonicus. Other toxigenic fungi detected were A. ochraceus (3 strains produced OTA), Aspergillus flavus (5 strains produced cyclopiazonic acid but not aflatoxins), P. citrinum (19 strains were strong citrinin producers) and Alternaria alternata (15 strains were producers of tenuazonic acid, alternariol and alternariol methyl ether). In spite of the high incidence of A. carbonarius capable of producing OTA, low levels of this toxin were detected in the samples analysed.

Ochratoxin A (OA) is a mycotoxin detected in a variety of food and feeds mostly from countries with a temperate climate because of the fungi that produce it, mainly Aspergillus ochraceus and Penicillium verrucosum. In Argentina, there is no available information about the natural occurrence of OA and ochratoxigenic fungi from feedstuffs. The aim was to evaluate the natural occurrence of OA in poultry, pig and rabbit feeds over 8 months. Likewise, the capacity to produce OA by Aspergillus section Nigri was investigated. Mycotoxin analysis showed that in some months of sampling, OA was detected in three feeds. OA was found in 38% of the poultry feed samples tested with levels ranging from 25 to 30 ng g(-1). From rabbit feed samples, 25% contained OA and the levels ranged from 18.5 to 25 ng g(-1). Only 13% of the pig feed samples were contaminated with similar levels of toxins. Ninety-four black Aspergillus strains from feedstuffs were tested for OA production. Among these, the tested species were A. niger var. niger, A. niger var. awamori, A. japonicus var. japonicus, A. japonicus var. aculeatus and A. foetidus. For the detection of OA, three methodologies were applied: the two TLC methods used for the fast screening of the filamentous fungi for the production of OA were not sensitive enough to detect OA in any of the black Aspergillus strains. When an HPLC methodology was used, the results showed that 46% of the black Aspergillus strains were producers of OA, with levels ranging from 13 to 25 ng ml(-1) culture medium. The highest percentage of ochratoxicogenic strains was isolated from rabbit feeds with 100 and 78% of A. niger var. niger and A. niger var. awamori, with mean levels of 15.5 and 14.6 ng ml(-1), respectively. From pig feeds, 61% of the A. niger var. awamori were producers of this toxin with mean levels of 16 ng ml(-1). In poultry feeds, the lowest percentage of OA producer strains was detected. The results for the occurrence of OA in feeds from different sampling months depended on storage and humidity-temperature conditions. Therefore, a good storage practice becomes very important to prevent OA production

Fumonisins B1 (FB1) and B2 (FB2) were determined in 35 samples of corn flour and corn grits destined for human consumption and purchased directly from Buenos Aires food shops and supermarkets from October 1996 to January 1997 and during the month of January 1998. During the first period of sample collecting, 16 out of 19 samples were found to be contaminated. Considering all 19 samples, contamination levels were between not detected and 1860 ng/g FB1, and from not detected to 768 ng/g FB2. During the second period all 16 samples were found to be contaminated with levels ranging from 75 to 4987 ng/g FB1, and from not detected to 1818 ng/g FB2. The levels of FB1 and FB2 in the samples collected during January 1998 were significantly higher than the samples collected during the period from October 1996 to January 1997. No significant difference was found in terms of fumonisin levels between the branded and unbranded samples.

Corn samples collected from the main production area in Argentina in 1995 were surveyed for the natural occurrence of Fusarium mycotoxins and aflatoxins. Fumonisins B1, B2 and B3 and zearalenone were found in all samples. A positive relationship was found between fumonisins B1, B2 and B3, B1 and B3, and B2 and B3. Deoxynivalenol and aflatoxins were not detected. Mycological survey has also revealed the predominance of Fusarium moniliforme. This is the first report on the simultaneous occurrence of fumonisins and zearalenone in corn from the main production area in Argentina.

The widespread occurrence of F. moniliforme and the toxic effects of its secondary metabolites, the fumonisins B1(FB1), B2(FB2) and B3(FB3), make it imperative that fumonisin contamination of maize, a major constituent of animal feed as well as the staple diet of many populations, be closely monitored to reduce the risk of fumonisin exposure. Equine leukoencephalomalacia and porcine pulmonary oedema have been associated with the intake of feed heavily contaminated with fumonisins. In addition, high levels of fumonisins in the maize-based staple diets of certain populations have been linked to a high incidence of oesophageal cancer in the Transkei region of South Africa and in Linxian and Cixian Counties, China. Bulk shipments of maize imported into South Africa from the USA and Argentina during 1992 were sampled at the port of entry to determine fumonisin levels. Of the 79 samples from two US shipments, all were positive for fumonisins, with FB1 constituting approximately 71% of the total fumonisins with an overall mean of 2.35 micrograms/gFB1. The maximum FB1 level observed was 3.9 micrograms/g. These levels contrast with those obtained from two Argentinian bulk shipments, which also were all positive for fumonisins, but had a mean FB1 level of 0.31 microgram/g and a maximum observed level of 0.7 microgram/g FB1 measured over 47 composite samples.

The purpose of this work was to determine the mycoflora and mycotoxins natural incidence in poultry feeds from 2 factories in Río Cuarto, Córdoba. One hundred and thirty samples were taken from May/1996 to May/1997. The most dominant species isolated of poultry feed samples belonged to the genera Aspergillus spp 85% and Fusarium spp 70%. From Aspergillus genus eleven species were identified and A. flavus was the most frequent. Nine species were identified from the Fusarium genus and the predominant was F. moniliforme. Penicillium ranked third in the number of isolated cases. From this genus twelve species were collected of which P. brevicompactum (15%), P. restrictum (14%) and P. purpurogenum (12%) were the most common. The most significant mycotoxin from poultry feeds was aflatoxin B1 (AFB1) found in 48% of the samples, with levels ranging from 10 to 123 ng/g. For zearalenone (ZEA) the levels were 327 to 5, 850 ng/g and DON was not detected from the samples. Due to the fact that in Argentina there is little information about this topic, these data on poultry feeds in our region would be of worldwide interest.

During the 1993 harvest period there was a high incidence of Fusarium head blight in wheat in Argentina. Fusarium species that produce trichothecenes in wheat have been reported in several countries including Argentina. Several studies have shown that F. graminerarum and deoxynivalenol (DON) were the main contaminants detected in wheat and by-products in Argentina. The objective of this study was to evaluate the occurrence of Fusarium spp. and DON contamination in wheat from Córdoba, Argentina during the 1993/94 harvest season. F. graminearum was the main Fusarium species isolated. From 40 samples analysed, 80% showed DON contamination. The levels of DON found ranged between 300 and 4500 micrograms/kg. There was good correlation between F. graminearum and DON contamination. Only five samples showed levels of DON higher than those established in the guidelines in Canada and the USA for food and feedstuffs.