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Highlights: [•] Bran content had no effect on toxins stability, while little effect of sourdough was observed. [•] Ochratoxin A was stable during the breadmaking process. [•] Fermentation affected DON levels, release taking place under some conditions. [•] Release of DON-3-G occurred during the breadmaking process. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) was analysed in composite samples of cereal-based baby foods, beer, breakfast cereals (corn- and rice and wheat-based), loaf bread, peanuts and pistachios. Foodstuffs were collected in hypermarkets and supermarkets from 12 cities in the Spanish region of Catalonia, and composite samples were prepared for analysis involving liquid–liquid extraction, followed by immunoaffinity column clean-up and HPLC with fluorescence detection. Consumption data for the selected foodstuffs were collected by means of a food-frequency questionnaire. The studied population was grouped by age in infants, children, adolescents and adults; and exposure to OTA through the specified foodstuffs, and through wine and coffee, was assessed. Exposure assessment was done through deterministic and probabilistic modelling of the contamination and consumption data. OTA occurrence and mean of positive samples (ng g−1 or ng ml−1, for beer) were the following: 8.7% and 0.233 in baby foods; 88.7% and 0.022 in beer; 2.8% and 0.728 in corn-based breakfast cereals; 25% and 0.293 in wheat-based breakfast cereals; 12.9% and 0.283 in loaf bread; 41.7% and 0.241 in peanuts; and 2.9% and 0.228 in pistachios. The median estimated daily intake of OTA through the foodstuffs by each age group were below the latest provisional tolerable daily intakes (PTDIs) of 17 and 14 ng kg−1 bw day−1 recommended by the European Food Safety Authority (EFSA) in 2006 and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 2007, respectively, ranging from 1% and 2% of those values in adolescents and children, to 3% and 11% in adults and infants. [ABSTRACT FROM PUBLISHER]

Abstract: This study aimed to: (1) determine the mycobiota of Capsicum powder samples, paying a special attention to the mycotoxigenic moulds; (2) evaluate the contamination levels of aflatoxins (AF), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), T2 and HT2 toxins in those samples. Thirty-two samples were obtained through the methods of sampling established by the European Union legislation. Aspergillus and Eurotium were the most frequently found genera. Aspergillus section Nigri had the higher relative frequency in the samples, A. niger aggregate being the most representative group of this section. Other potentially mycotoxigenic Aspergillus, Fusarium and Penicillium species were found, but in a lower frequency. Co-occurrence of mycotoxins was confirmed in the 32 Capsicum powder samples. All samples were contaminated with AF and OTA, 27% with ZEA (36% of chilli and 18% of paprika samples), 9% with DON (18% of chilli and 6% of paprika samples), 6% with T2 (18% of chilli samples) and none of the samples contained HT2. Although in the present study the most common genera found (Aspergillus and Eurotium) belong to storage moulds, some field fungi such as Fusarium spp. were also found, and their toxins were sometimes detected. This fact supports the hypothesis that mycotoxin contamination of Capsicum products may occur both in the field and/or during storage. [Copyright &y& Elsevier]

Abstract: The aim of this study was to determine the co-occurrence of aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA) in paprika and chilli samples purchased in Spain, using HPLC with fluorescence detection. The occurrence of mycotoxin in 64 paprika samples was 59% for AFs, 98% for OTA and 39% for ZEA, whereas in the 35 chilli samples, the contamination was 40% for AFs, 100% for OTA and 46% for ZEA. None of the samples had AFs levels higher than the legally allowable limits. Regarding the co-occurrence of mycotoxins, 75% of paprika samples and 65% of chilli samples contained more than one mycotoxin. Chilli samples generally had lower concentrations of AFB1, AFB2, total AFs and OTA than had paprika samples. The high incidence of OTA contamination suggests that additional legislation may be required to for these kinds of spices. [Copyright &y& Elsevier]

A survey of the fungal contamination and occurrence of aflatoxins and ochratoxin A (OTA) in 50 pistachio nut samples collected from commercial stores around Catalonia (Spain) was carried out. Aspergillus flavus was found in 30% of samples, whereas Aspergillus section Nigri, Aspergillus ochraceus, and Penicillium verrucosum were found in 40%, 2% and 26% of samples, respectively. A total of 204 fungal isolates were obtained; 70.8% of A. flavus isolates were able to produce aflatoxin B1 and B2, whereas OTA production capacity was detected in 54.4% of the A. section Nigri biseriate isolates. Aflatoxins were detected in five samples (10% of total), all exceeding the maximum legal limit set for aflatoxin B1 (2 µg kg-1) or for total aflatoxins (4 µg kg-1), with one sample having a very high level of contamination (1134.5 µg kg-1). Only one sample of pistachio showed OTA contamination at 0.67 µg kg-1. Simultaneous contamination by aflatoxins and OTA was not observed in these samples. It was concluded that the frequency of aflatoxins and OTA contamination in pistachio samples available in the Spanish market is relatively low. Thus, no significant contribution to health risk should be expected from aflatoxin consumption through pistachios among healthy consumers. However, the existence of single samples with an extremely high aflatoxin concentration reinforces the need for effective prevention strategies in pistachio processing and commercialization. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the effect of Botrytis cinerea growth on ochratoxin A (OTA) production by Aspergillus carbonarius and degradation. Methods and Results: OTA-producing A. carbonarius and B. cinerea were grown on grape-like medium at 20°C for 7 days. Radii of colonies were daily recorded and OTA was analysed. In addition, each B. cinerea isolate was inoculated on grape-like synthetic nutrient medium (SNM) paired with each A. carbonarius isolate at a distance of 45 mm. Botrytis cinerea isolates were also grown in OTA-spiked SNM. Growth rates of B. cinerea and A. carbonarius were 20 and 7·5 mm day−1, respectively. The growth of the colonies of each species stopped when they contacted each other in paired cultures. OTA production by A. carbonarius in the contact area was affected by B. cinerea, but no clear trend was observed. All B. cinerea isolates showed to degrade between 24·2% and 26·7% of OTA from spiked SNM. Conclusions: The ecological advantage of B. cinerea, in terms of growth rate, vs. OTA-producing Aspergillus in some wine-growing regions and its ability to degrade OTA may explain the low levels of this toxin in noble wines. Significance and Impact of the Study: At determinate conditions, the presence of B. cinerea in grapes with A. carbonarius may help in reducing OTA accumulation. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the impact of modified atmosphere packaging on in vitro growth of Aspergillus carbonarius and Aspergillus niger, and possible effects on ochratoxin A (OTA) biosynthesis. Methods and Results: Ochratoxigenic isolates belonging to the species A. carbonarius and A. niger were grown on a synthetic grapejuice medium (SNM) and packaged in combinations of controlled O2 (1% and 5%) and CO2 levels (0% and 15%), and in air as a control. Colony diameters were recorded every 3 days up to 21 days, and OTA was analysed after 7, 14 and 21 days. The greatest reductions in mycelial growth rate were observed at 1% O2 followed by 1% O2/15% CO2, whereas 5% O2 stimulated the growth of all isolates. OTA production by A. carbonarius and A. niger isolates was minimized at 1% O2/15% CO2 and 1% O2, respectively, after 7 days of incubation. Maximal OTA accumulation after 7 days was observed for all isolates in the control pack and at 5% O2. Conclusions: Of the atmospheres tested, only 1% O2 combined with 15% CO2 consistently reduced fungal growth and OTA synthesis by A. carbonarius and A. niger. Significance and Impact of the Study: Storage under modified atmospheres is unlikely to be suitable as the sole method for OTA minimization and grape preservation; other inhibitory factors are necessary. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the impact of skin damage on Aspergillus carbonarius colonization and ochratoxin A (OTA) production in grapes at different temperatures and relative humidity. Four ochratoxigenic A. carbonarius strains isolated from wine grapes were used to inoculate artificially damaged and undamaged table grapes. Grapes were stored at three levels of relative humidity (80%, 90% and 100%) and at two temperatures (20 and 30°C). After seven days, the infection percentage of A. carbonarius was recorded and OTA accumulation in berries was analysed. Damaged grapes were more commonly infected and development of colonies was higher than in undamaged ones; consequently more OTA was detected in the former treatment. Temperature and relative humidity had significant influences on both infection and toxin content. The amount of OTA detected at 30°C was higher than at 20°C in most of the treatments. The highest relative humidity (100%) led to maximum amounts of OTA while no significant differences were found between 90% and 80% in the OTA content. The implementation of preventive measures in order to minimise berry damage in the field by controlling pathogenic fungi and insects during grape growing and removing visibly damaged grapes at harvest may significantly reduce OTA contamination in grapes. [Copyright &y& Elsevier]

Aims: To evaluate the effect of preharvest grape pesticides in Aspergillus section Nigri infection in dehydrating grapes and the final ochratoxin A (OTA) content. Additionally, the effect of coinoculation of moulds frequently isolated from grapes and raisins on Aspergillus section Nigri infection was studied. Methods and Results: Fungicide-treated grapes were inoculated with Aspergillus carbonarius, Aspergillus niger aggregate, Eurotium amstelodami and Penicillium janthinellum in different combinations, then dehydrated by reducing aw for 20 days. The percentages of colonized grapes treated with fungicides were, in general, lower, but no differences were observed among fungicides. The untreated grapes always showed higher concentrations of OTA, regardless of the inoculum applied. In general, Chorus was the most effective antifungal treatment in reducing OTA accumulation in grapes during dehydration. Penicillium janthinellum reduced Aspergillus section Nigri colonization and OTA accumulation in grapes during dehydration. Conclusions: The four preharvest fungicides studied reduced the Aspergillus section Nigri growth and OTA production by A. carbonarius during dehydration of grapes. Significance and Impact of the Study: The success of these chemical treatments might depend on the mycobiota composition of grapes. [ABSTRACT FROM AUTHOR]

A study was undertaken to evaluate the impact of the application of several fungicide treatments used in Spanish vines on Aspergillus carbonarius growth and ochratoxin A production. Three trials were designed in order: (1) to screen 26 fungicides at the doses recommended by manufacturers on grape-like synthetic medium at 20 and 30°C; (2) to find out the minimum inhibitory concentration of each fungicide for A. carbonarius growth on synthetic medium; and (3) to investigate the effect of several fungicides on A. carbonariu s-inoculated grapes. In synthetic medium nine fungicides significantly reduced A. carbonarius growth rate. Meanwhile, 13 fungicides completely inhibited its growth. In general, growth was faster at 30°C than at 20°C, contrary to ochratoxin A production. Fungicides that stopped fungal growth also inhibited ochratoxin A production, but not all the fungicides that reduced growth reduced the ochratoxin A synthesis. In general, fungicides that contained copper or strobilurins reduced both growth and ochratoxin A production, contrary to sulphur fungicides. At the optimum temperature for A. carbonarius growth of 30°C, higher amounts of fungicide were needed to prevent fungal growth than at 20°C. Among the fungicides that inhibited A. carbonarius growth on synthetic medium at the initial doses, cyprodinil seemed to be the active ingredient more effective at stopping fungal growth when testing reduced doses. The fungicide effect on grapes was similar to that on synthetic medium. Both infection and ochratoxin A production were reduced when using cyprodinil (37.5%) plus fludioxonil (25%) and azoxystrobin (25%). Penconazole (10%) also showed a clear reduction in ochratoxin A production at both temperatures, although infection was only reduced at 20°C. Ochratoxin A reduction was strain and temperature-dependent. In general, fenhexamid (50%), mancozeb (80%) and copper hydroxide (80%) plus copper (50%) enhanced infection and ochratoxin A production. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a secondary metabolite produced by several species of Aspergillus and Penicillium ; among them Aspergillus ochraceus and Penicillium verrucosum are two ochratoxigenic species capable of growing in different climates and thus contamination of food crops with OTA can occur worldwide. OTA can be found in a wide range of foods such as cereals, coffee, cocoa, spices, beer, wine, dried vine fruit, grapes and meat products. OTA is toxic to animals, it presents neurotoxic, immunotoxic and nephrotoxic effects. It has been implicated in a human kidney disorder known as Balkan Endemic Nephropathy. This review focuses on the ecophysiology of ochratoxin-producing Aspergillus ochraceus and Penicillium verrucosum , the effect of environmental factors on their germination, mycelial growth, and OTA production. Knowledge of environmental conditions required for sucessive stages of fungal development represent the first step towards preventing mycotoxin formation. Predictive models for different stages of fungal development are presented, which allow prediction of the time before spoilage as a function of the abiotic factors. Finally, the implications of these studies in management of barley, coffee and grapes are described. This can help to identify the critical control points in their production, storage and distribution processes. [ABSTRACT FROM AUTHOR]

Abstract: Aspergillus ochraceus is an ochratoxin A (OTA) producer mould found in grapes and this may contribute to OTA contamination in wines and grape juices. The influence of relative humidity (R.H.; 80, 90 and 100%) and temperature (10, 20 and 30°C) on visible mould growth on grapes and OTA accumulation after 14 days of incubation by this fungal species has been studied using a full factorial design with three replicates. The two abiotic factors and their interaction (R.H.×temperature) affected significantly the A. ochraceus growth in berries, which was maximum at 90–100% R.H. levels. With regard to the optimum temperature level, it occurred at 30°C at 80 and 90% R.H., whereas no significant differences were detected at 20 and 30°C when R.H. was 100%. OTA production by A. ochraceus on grapes was not significantly modified by the assayed levels of temperature and R.H, with a mean value of 3.53ngg−1. Predictive models of percentage of grapes with visible growth of A. ochraceus isolates under different relative humidity and temperature are presented. [Copyright &y& Elsevier]

a. valero, s. marín, a.j. ramos and v. sanchis. 2005. To explain the dominance of OTA-producing fungal species in sun-dried grapes for special wine production through an ecophysiological approach. Grapes at different ripening stages, sun-dried grapes and raisins were analysed for fungal presence, and isolates identified. Aspergillus section Nigri incidence in grapes increased with grape maturation. In the ecophysiological study five isolates ( Alternaria alternata, Cladosporium herbarum, Penicillium decumbens, Aspergillus carbonarius, A. niger aggregate and A. section Nigri uniseriate) were inoculated in SNM medium at four aw (0·82–0·97) and incubated at 20, 30 and 40°C for 18 d. Isolates were also inoculated in pairs to evaluate fungal interactions recording their growth rates and indexes of dominance. Aspergillus section Nigri grew in a wider range of temperature and aw, had higher growth rates than the others under most of the conditions tested and showed behaviour usually dominant. The presence of A. section Nigri is predominant in grapes during harvesting and sun-drying period likely because of a better adaptation to hot and humid environment. The duration of the drying period should be reduced as much as possible without compromising the quality of the final product, or drying the grapes in controlled chambers with dry hot air flow. [ABSTRACT FROM AUTHOR]

n. bellí, a.j. ramos, i. coronas, v. sanchis and s. marín. 2005.The effects of water activity (0·90–0·99aw), temperature (15–37°C), and their interaction on growth and ochratoxin A (OTA) production by eight isolates ofAspergillus carbonariuswere investigated on synthetic nutrient medium (SNM) with composition similar to grapes.Growth data were modelled by an multiple linear regression and response surface models were obtained.Aspergillus carbonariusgrew much faster at 30°C than at the other temperature levels tested and its growth rate increased with increasingaw, maximum growth rate being between 0·95 and 0·99aw. In general, isolates grew faster at 35–37°C than at 20°C, although no significant differences were found between these temperatures. OTA accumulation was also favoured by highaw levels, and although it was observed in the whole range of temperatures, maximum amounts were detected at 20°C. No OTA was found at the most unfavourable growth conditions.Optimumaw level for growth seems to correspond with optimum for OTA production, meanwhile the most propitious temperature for the toxin production was below the best one for growth.Prediction ofA. carbonariusgrowth would allow estimating their presence and therefore, the OTA production, as it was found that conditions for the toxin production were more limited than those permitting growth. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a secondary metabolite of Aspergillus and Penicillium species, including Aspergillus ochraceus, a species that can be found in stored cereal grains such as barley. The objective of this study was to determine the effects of water activity (aw, 0.80–0.99), temperature (10, 20, 30 °C), and A. ochraceus isolate differences on radial growth and OTA production in irradiated barley grains. The three isolates showed optimal conditions for growth and ochratoxin A production at 0.99 aw and 30 °C, with a marked decrease of growth rates and OTA production at the lowest levels of aw and temperature assayed. The minimum aw level for growth, observed in this study, was 0.85 and 0.90 aw for OTA production. Significant differences among the isolates were found. Lag phases prior to fungal growth and OTA production values were modelled by multiple linear regression and response surface models. These models could provide an approximate prediction of growth and OTA production. [Copyright &y& Elsevier]

Abstract: Ochratoxin A (OTA) has been found in pre-harvest and freshly harvested wheat. Spanish climatic conditions point to Aspergillus species as probably responsible for this OTA. In this study the effectiveness of 5 non-specific antifungal chemicals used on wheat fields (25.9% tebuconazole+60.0% N,N-capramide dimethyl; 12.70% tebuconazole+12.7% prothioconazole+59.5% N,N‐amide dimethyldecane; 12.5% epoxiconazole; 12.5% tetraconazole; and 70% thiophanate methyl) and an extract from Equisetum arvense were investigated in vitro on wheat by recording growth (colony size, fungal growth and DNA concentration) and OTA production of two ochratoxigenic isolates of Aspergillus carbonarius and three of A. steynii, simulating current and extreme climatic conditions. Inoculated wheat was incubated under two alternating temperature cycles (20/30°C and 25/35°C) with photoperiod (14/10h lightness/darkness), and two moisture levels (40 and 25%). The Aspergillus species tested seemed to be able to persist in predicted future climatic conditions, in particular, A. steynii, a high OTA producer. Azoles were effective in controlling the growth of A. carbonarius and A. steynii, and this effectiveness may not be compromised by the increase in temperature and decrease of humidity. However, azoles are not useful for the prevention of OTA accumulation, which could be only reduced in A. carbonarius under non-extreme conditions. Although some adjustment will probably be required, further studies should be conducted in the field, since the antifungals used in this study are applied at flowering and not directly on the grain. Moreover, timing of antifungal application may need to be optimized. Finally, Equisetum extract showed promising results as an antifungal, however further work to adjust the applied concentrations is required. [Copyright &y& Elsevier]

Abstract: Grapes from three different regions with a long winemaking tradition in Spain were analysed at different growth stages in order to identify the ochratoxigenic mycobiota during three consecutive seasons. The correlation between meteorological parameters and ochratoxigenic fungi was studied and revealed a significant positive correlation between black aspergilli infection and temperatures in the month preceding each sampling date. No significant correlation was found with either relative humidity or rainfall. Biodiversity indexes were also calculated in this study. Black aspergilli species were the most abundant in grapes before harvest, and among them, Aspergillus carbonarius was the main ochratoxin A (OTA) producer species and represented 78–100% of the isolates tested. The results obtained support the key role of A. carbonarius as the main source of OTA contamination in grapes. [Copyright &y& Elsevier]

Abstract: The aim of this study was to determine the effect of a natural carotenoid mixture (Capsantal FS-30-NT), containing capsanthin and capsorubin, on growth and mycotoxin production of ochratoxin A-producing A. ochraceus, A. westerdijkiae, and A. tubingensis isolates. One isolate of each species, previously isolated from paprika or chilli, was inoculated on Czapek Yeast extract Agar (CYA) medium supplemented with different amounts of capsantal (0 to 1%) and incubated at 10, 15 and 25°C for 21days. Growth rates and lag phases were obtained, and OTA production was determined at 7, 14 and 21days. The taxonomically related A. ochraceus and A. westerdijkiae showed the same behavior at 15°C, but A. ochraceus was able to grow at 10°C and had higher growth rates at 25°C. A. tubingensis had the highest growth rates and lowest OTA production capacity of the assayed isolates, and it was not able to grow at 10°C. Capsantal addition resulted in increased lag phases at 15°C for all the strains, while growth rates remained rather constant. At 25°C capsantal reduced growth rates, with rather constant lag phases. However, the effect of capsantal on OTA production was inconclusive, because it depended on temperature or time, and mostly was not significant. Low temperature has been a crucial factor in OTA production, regardless of the capsantal concentration tested, especially for A. tubingensis and A. westerdijkiae. Industrial storage temperature for paprika and chilli is approximately 10°C. If this temperature is maintained, mould growth and OTA production should be reduced. [ABSTRACT FROM AUTHOR]

Abstract: The effect of light and temperature regimes simulating day and night in the field in the months preceding grape harvest on Aspergillus carbonarius growth and ochratoxin A (OTA) production were investigated. Twelve-hour photoperiod affected positively A. carbonarius growth with no differences between incubating the mould at day temperature (28°C) or alternating day/night temperatures (28°C/20°C). Slower growth, however, was observed with constant incubation at 20°C. Under 12h-alternation periods of day and night temperatures, growth was faster at continuous darkness than under continuous light conditions. Light did not cause any morphological changes in the aspect of the colonies. No significant differences on OTA production were detected due to either fluctuating temperature or photoperiod. However, as photoperiod enhanced the growth of colonies, it also enhanced OTA accumulation. The ability of A. carbonarius to produce OTA reported in previous laboratory studies has been demonstrated to be stimulated in field conditions. [Copyright &y& Elsevier]

Abstract: Aspergillus ochraceus is an important contaminant of diverse substrates, such as cereals, coffee, grapes and derivates. This fungus produce a nephrotoxic metabolite, ochratoxin A (OTA), whose presence on food and feeds may be an important risk for animal and human health. The aim of this work was to evaluate the significance of the origin of A. ochraceus isolates on their OTA production patterns on different substrates (yeast extract sucrose (YES) broth, irradiated barley grains, irradiated green coffee beans and sterilized grapes) and under different environmental conditions. Results did not show a significant influence of the isolation source on OTA-production profiles by A. ochraceus isolates on several substrates, since the isolates which produced the highest OTA amounts in vitro (YES medium) were also the isolates with the highest OTA yields on the other substrates. Abiotic factors assayed (water activity, temperature and substrate) affected significantly OTA productions by A. ochraceus. Maximum OTA amounts were detected at 25°C and 0.98 a w on all substrates tested. The highest OTA accumulations found on the different substrates were: green coffee beans (> 2mgg−1), barley grains (∼1mgg−1), YES medium (13.9μgml−1) and grape (∼3ngg−1). [Copyright &y& Elsevier]