Natural multi-occurrence of mycotoxins in rice from Niger State,Nigeria

Twenty-one rice samples from field (ten), store (six) and market (five) from the traditional rice-growing areas of Niger State, Nigeria were analysed for aflatoxins (AFs), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), fumonisin B₁ (FB₁) and B₂ (FB₂), and patulin (PAT) by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) respectively. T-2 toxin was determined using TLC only. AFs were detected in all samples, at total AF concentrations of 28–372 μg/kg. OTA was found in 66.7% of the samples, also at high concentrations (134–341 μg/kg) that have to be considered as critical levels in aspects of nephrotoxicity. ZEA (53.4%), DON (23.8), FB₁ (14.3%) and FB₂ (4.8%) were also found in rice, although at relatively low levels. T-2 toxin was qualitatively detected by TLC in only one sample. Co-contamination with AFs, OTA, and ZEA was very common, and up to five mycotoxins were detected in a single sample. The high AF and OTA levels as found in rice in this study are regarded as unsafe, and multi-occurrences of mycotoxins in the rice samples with possible additive or synergistic toxic effects in consumers raise concern with respect to public health.     

Co-occurrence of mycotoxins in swine feed produced in Portugal

A total of 404 samples of commercial swine feed from Portugal feed mills were analysed by HPLC methods for the presence of mycotoxins: 277 samples of feed for fattening pigs were analysed for ochratoxin A (OTA), zearalenone (ZEA), and deoxynivalenol (DON), and 127 samples of feed for sows were analysed for ZEA and fumonisins (FB₁ + FB₂). Concerning feed for fattening pigs, 21 (7.6%) samples were positive for OTA, (2–6.8 μg/kg), 69 (24.9%) were positive for ZEA (5–73 μg/kg), and 47 (16.9%) were positive for DON (100–864 μg/kg). In feed for sows, the results showed 29.9% of positive samples for ZEA (5–57.7 μg/kg) and 8.7% positive samples for FB₁ and FB₂ (50–391.4 μg/kg). Co-occurrence of DON/ZEA was found most frequently, but simultaneous contamination with OTA/ZEA and OTA/DON was also found.     

Mycotoxigenic potential of fungi isolated from freshly harvested Argentinean blueberries

Alternaria alternata, A. tenuissima, Fusarium graminearum, F. semitectum, F. verticillioides, Aspergillus flavus, and Aspergillus section Nigri strains obtained from blueberries during the 2009 and 2010 harvest season from Entre Ríos, Argentina were analyzed to determine their mycotoxigenic potential. Taxonomy status at the specific level was determined both on morphological and molecular grounds. Alternariol (AOH), alternariol monomethyl ether (AME), aflatoxins (AFs), zearalenone (ZEA), fumonisins (FBs), and ochratoxin A (OTA) were analyzed by HPLC and the trichotecenes deoxynivalenol (DON), nivalenol (NIV), HT-2 toxin (HT-2), T-2 toxin (T-2), fusarenone X (FUS-X), 3-acetyl-deoxynivalenol (3-AcDON), and 15-acetyl-deoxynivalenol (15-AcDON) by GC. Twenty-five out of forty two strains were able to produce some of the mycotoxins analyzed. Fifteen strains of Aspergillus section Nigri were capable of producing Fumonisin B₁ (FB₁); two of them also produced Fumonisin B₂ (FB₂) and one Fumonisin B₃ (FB₃). One of the F. graminearum isolated produced ZEA, HT-2, and T-2 and the other one was capable of producing ZEA and DON. Two A. alternata isolates produced AOH and AME. Four A. tenuissima were capable of producing AOH and three of them produced AME as well. One Aspergillu flavus strain produced aflatoxin B₁ (AFB₁), aflatoxin B₂ (AFB₂), and aflatoxin G₁ (AFG₁). To our knowledge, this is the first report showing mycotoxigenic capacity of fungal species isolated from blueberries that include other fungi than Alternaria spp.     

Simultaneous occurrence of mycotoxins in human food commodities from Cameroon

Eighty-two samples of dried food commodities from Cameroon were screened and quantified for different mycotoxins, including fumonisin B₁ (FB₁), zearalenone (ZEA), deoxynivalenol (DON), aflatoxin (AF) and ochratoxin A (OTA), by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), respectively. The percentage of positive samples was as follows: FB₁ 41%, AF 51%, ZEA 57%, DON 65% and OTA 3%. High FB₁ contents were found in maize, averaging 3,684 μg/kg (range: 37-24,225 μg/kg), whereas the highest average ZEA level was found in peanuts (70 μg/kg), followed by maize (69 μg/kg), rice (67 μg/kg) and beans (48 μg/kg) with no ZEA was detected in soybeans. DON contents were low, ranging from 13 to 273 μg/kg, and for AF the average content was 2.6 μg/kg with peanuts and maize as principal substrates. The incidence of OTA was low, with a mean level of 6.4 μg/kg recorded. The majority (79%) of samples contained more than one mycotoxin and the most frequent co-occurrence found was FB₁ + ZEA + DON, detected in 21% of samples (mainly maize) analysed. Co-contamination with FB₁ + ZEA + DON + AF was found in 11% of the samples. Although a large proportion of samples had fairly low levels of individual mycotoxins, this should be of concern as the co-occurrence of mycotoxins may generate additive or synergistic effect in humans, especially if the respective commodities are consumed almost on a daily basis.     

Mycotoxins in horse feed

A total of 62 samples of commercial horse feed preparations (complementary feeds) containing cereal mixtures (“muesli” or mash, n = 39; pelleted feeds, n = 12), and plain horse feed grains (maize, n = 5; oats, n = 4; barley, n = 2) were purchased from 21 different producers/distributors from the German market. All samples were analysed by competitive enzyme immunoassays (EIA) for six different mycotoxins (mycotoxin groups). Analytes (detection limit, mean recovery) were: deoxynivalenol (DON, 10 μg/kg, 84%), zearalenone (ZEA, 5 μg/kg, 93%), fumonisin B₁ (FB₁, 2 μg/kg, 113%), T-2 toxin (T-2, 0.1 μg/kg, 71%), sum of T-2 + HT-2 toxin (T-2/HT2, 0.2 μg/kg, 97%), ochratoxin A (OTA, 0.2 μg/kg, 67%), and total ergot alkaloids (Generic Ergot Alkaloids “GEA”, 30 μg/kg, 132%). All samples contained DON (16–4,900 μg/kg, median 220 μg/kg), T-2/HT-2 (0.8–230 μg/kg, median 24 μg/kg), and T-2 (0.3–91 μg/kg, median 7 μg/kg). ZEA was detected in 98% of the samples (7–310 μg/kg, median 61 μg/kg). Most samples (94%) were positive for FB₁ (2–2,200 μg/kg, median 27 μg/kg). Ergot alkaloids were detected in 61% of samples (28–1,200 μg/kg, median 97 μg/kg), OTA was found in 42% of samples (0.2–4 μg/kg, median 0.35 μg/kg). The results demonstrate that a co-contamination with several mycotoxins is very common in commercial horse feed from the German market. The toxin concentrations were in most cases well below the levels which are usually considered as critical or even toxic. The highest mycotoxin concentrations were mostly found in single-grain cereal feed: the maximum values for DON and FB₁ were found in maize, the highest T-2/HT-2 toxin concentrations were found in oats, and the highest concentration of ergot alkaloids was found in barley. In composed feeds, no correlation between cereal composition and mycotoxin levels could be found.     

Natural Occurrence of 16 Fusarium Toxins in Grains and Feedstuffs of Plant Origin from Germany

A total of 220 samples comprising cereals, cereal byproducts, corn plants and corn silage as well as non-grain based feedstuffs was randomly collected during 2000 and 2001 from sources located in Germany and analysed for 16 Fusarium toxins. The trichothecenes scirpentriol (SCIRP), 15-monoacetoxyscirpenol (MAS), diacetoxyscirpenol (DAS), T-2 tetraol, T-2 triol, HT-2 and T-2 toxin (HT-2, T-2), neosolaniol (NEO), deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivealenol (15-ADON), nivalenol (NIV) and fusarenon-X (FUS-X) were determined by gas chromatography/mass spectrometry. Zearalenone (ZEA) and α- and β-zearalenol (α- and β-ZOL) were analysed by high performance liquid chromatography with fluorescence and UV-detection. Detection limits ranged between 1 and 19 μg/kg. Out of 125 samples of a group consisting of wheat, oats, corn, corn byproducts, corn plants and corn silage only two wheat samples did not contain any of the toxins analysed. Based on 125 samples the incidences were at 2–11% for DAS, NEO, T-2 Triol, FUS-X, α- and β-ZOL, at 20–22% for SCIRP, MAS, T-2 tetraol and 3-ADON, at 44–74% for HT-2, T-2, 15-ADON, NIV and ZEA, and at 94% for DON. Mean levels of positive samples were between 6 and 758 μg/kg. Out of 95 samples of a group consisting of hay, lupines, peas, soya meal, rapeseed meal and other oilseed meals, 64 samples were toxin negative. DAS, T-2 triol, NEO and FUS-X were not detected in any sample. The incidences of DON and ZEA were at 14 and 23% respectively, those of the other toxins between 1–4%, mean levels of positive samples were between 5 and 95 μg/kg.     

The phytotoxicity of selected mycotoxins on mature,germinatingZea mays embryos

Mature maize (Zea mays) embryos were exposed to 5, 10 and 25 µg ml^–1 of deoxynivalenol (DON), zearalenone (ZEA), ochratoxin A (OA) and a mixture of zearalenone and deoxynivalenol (ZEA/DON) for 9 days. DON and the ZEA/DON combination were consistently more inhibitory of the measured parameters than either ZEA or OA. Based on the predicted additive values, it would appear that, in combination, ZEA and DON act synergistically to inhibit root and shoot growth. For ZEA alone, a concentration of 5 µg ml^–1 ZEA was generally inhibitory of root and shoot elongation and fresh mass accumulation, while at 10 and 25 µg ml^–1, this toxin had a stimulatory effect on these parameters. For OA, the measured effects on root and shoot growth at 5 and 25 µg ml^–1 were stimulatory, while at 10 µg ml^–1 OA, an inhibitory effect was observed. For all toxins, inhibitory/stimulatory effects were generally more marked for root parameters than for shoot elongation or mass.Abbreviations ADON acetyldeoxynivalenol - AFB₁ aflatoxin B₁ - DAS diacetyoxyscirpenol - DON deoxynivalenol - FB₁ fumonisin B₁ - FHB Fusaium head blight - MON moniliformin - NIV nivalenol - OA ochratoxin A - ZEA zearalenone     

Effects of fumonisin B1 alone and combined with deoxynivalenol or zearalenone on porcine granulosa cell proliferation and steroid production

Fumonisin B₁ (FB₁) is a Fusarium mycotoxin frequently occurring in corn in combination with deoxynivalenol (DON) and zearalenone. The aim of this study was to determine if FB₁, alone and combined with DON or α-zearalenol (ZEA), zearalenone major active metabolite, can affect granulosa cell proliferation, steroid production, and gene expression in swine. Porcine granulosa cells were cultured for 2 days in serum-containing medium followed by 1 or 2 days in serum-free medium with or without added treatments. Fumonisin B₁ had inhibitory effects on granulosa cell proliferation. Deoxynivalenol strongly inhibited cell growth, and no significant difference was detected in combination with FB₁. α-Zearalenol showed a stimulatory effect on granulosa cell numbers even in combination with FB₁. Regarding steroid production, FB₁ increased progesterone production, and FB₁ had no effect on estradiol production. Deoxynivalenol strongly inhibited progesterone and estradiol production, and FB₁ had no significant effect on this response. α-Zearalenol increased progesterone production, and its combination with FB₁ produced additive effects. α-Zearalenol had no effect on estradiol production, whereas it decreased estradiol production when co-treated with FB₁. Fumonisin B₁ was found to decrease CYP11A1 messenger RNA abundance, and the stimulatory effect of FB₁ on progesterone production was found to be not dependent on 3-hydroxy-3-methylglutaryl-coenzyme A reductase activity suggesting that FB₁ increases progesterone production through a different mechanism. The results show that these Fusarium mycotoxins can influence porcine granulosa cell proliferation and steroid production, thereby demonstrating their potential reproductive effects on swine.     

Determination of mycotoxins in bovine milk by liquid chromatography tandem mass spectrometry

Liquid chromatographic/tandem mass spectrometric methods using pneumatically assisted electrospray ionisation (LC-ESI-MS/MS) was developed for determination of 18 mycotoxins and metabolites-ochratoxin A, zearalenone, alpha-zearalenol, beta-zearalenol, alpha-zearalanol (zeranol), beta-zearalanol (taleranol), fumonisin B1, fumonisin B2, T-2 toxin, HT-2 toxin, T-2 triol, diacetoxyscirpenol (DAS), 15-monoacetoxyscirpenol (MAS), deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-AcDON), 15-acetyldeoxynivalenol (15-AcDON), deepoxy-deoxynivalenol (DOM-1) and aflatoxin M1--in milk. The mycotoxins were extracted and cleaned up simultaneously. Extraction and removal of lipophilic compounds was performed at pH 2 using a two-phase mixture of acetonitrile and hexane. The acetonitrile concentration of the aqueous phase was reduced and the pH was adjusted to 8.5 before clean up by solid phase extraction (SPE) on Oasis HLB. The toxins DON, DOM-1, 3-AcDON, 15-AcDON, ochratoxin A, zearalenone, alpha-zearalenol, beta-zearalenol, alpha-zearalanol and beta-zearalanol were detected in negative ion mode after separation on a Hypersil ENV analytical column, while the toxins T-2 toxin, HT-2 toxin, T-2 triol, DAS, MAS, fumonisin B1, fumonisin B2 and aflatoxin M1 were detected in positive ion mode after separation on a Luna C18 column. Two transition products were monitored for each compound. The extraction and SPE conditions were optimised to obtain maximum recovery and minimum signal suppression/enhancement. The detection capabilities related to the transition products of lowest abundance were in the range 0.020-0.15 microg/l. The mean true recoveries were in the range 76-108% at levels of 0.2-10 microg/l.     

Zearalenone, deoxynivalenol and fumonisins in mixed-feed for laying hens

Fusarium toxins are secondary metabolites produced byfungi of these genera in many commodities under certain conditions. A study was carried out to investigate the co-occurrence of zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FB₁ and FB₂) in 52 samples of mixed-feed for poultry contaminated withFusarium verticillioides. The zearalenone and deoxynivalenol were checked using immunoaffinity column and the extraction of fumonisin was performed by strong anion exchange (SAX) solid phase column. Detection and quantification were determined by high performance liquid chromatography (HPLC). The limit of detection was 5 μg/kg for ZEN, 100 μg/kg for DON and 50 and 100 μg/kg for FB₁ and FB₂ respectively.Fusarium toxins were detected in 20 samples. Sixteen samples were positive for ZEN (30.7%) presenting levels that ranged from 7.4 μg/kg to 61.4 μg/kg (mean=27.0 μg/kg). 13.5% of the samples presented contaminations of DON, with levels ranging from 100.0 μg/kg to 253 μg/kg (mean=l18.07 μg/kg). FB₁ was detected in 19.2% of samples, with levels ranging from 50.0 μg/kg to 110.0 μg/kg (mean=73.6 μg/kg). FB2 was not detected in any sample. In positive samples simultaneously contamination with two or three mycotoxins were detected in 9 of them (17.3%).     

Histopathological and cytolosical abnormalities induced by fusarial toxins in mice (Mus musculus)

Three fusarial toxins vi z., zearal enone (ZEA), deoxynivalenol (DON) and T-2 were administered orally to mice (Mus musculus) under two different treatments. In the -first treatment, the toxins were -fed at the rate o-f 0.5 mg/kg body weight (ZEA), 3mg/kg body weight (DON), and 0.5mg/kg body weight (T-2) -for eight weeks (twice a week) . In another set o-f experiments the toxins were .given daily by mixing with the -feed at a concentration commonly -found in -food and -feed items as natural contaminants. The a-f-fected animals showed significant changes in body weight. T-2 toxins caused swelling o-f stomach in most o-f the treated animals. Portal and periportal fibrosis in liver was also very common. Enlargement o-f urinary bladder was observed in ZEA fed animals. Cytological studies in bonemarrow cells showed fragmentation, chromosome breaks, stickiness and clumping of chromosome.     

Zearalenone,deoxynivalenol and aflatoxin B<Subscript>1</Subscript> and their metabolites in pig urine as biomarkers for mycotoxin exposure

Methods to determine zearalenone (ZEA), deoxynivalenol (DON), aflatoxins (AF) and their metabolites in pig urine were developed as biomarkers for pig exposure to the mycotoxins in feed. Urine samples were incubated with β-glucuronidase to cleave conjugates, extracted and cleaned-up with solid phase and immunoaffinity columns, followed by HPLC with UV and fluorescence detection. Good recoveries (83–130%), low variation (2–10%), and low detection limits (0.3–9.9 ng/ml) were obtained. The results of controlled AFB₁ feeding trials found no difference in urine concentrations of AFB₁ or AFM₁ from pigs fed three different levels (127, 227, 327 μg/kg) of AFB₁ in diets. The excretion of AFB₁ and AFM₁ in urine was on average 30% of the oral dose and the ratio AFB₁ to AFM₁ was around 23%. The analysis of 15 Vietnamese pig urine samples indicate a relatively high exposure of ZEA, DON and AF, which were found as toxin or metabolites in 47, 73, and 80% of the urine samples, respectively.     

Comparative effects of trichothecene mycotoxins on bovine platelet function: Acetyl T-2 toxin,a more potent inhibitor than T-2 toxin

The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10^?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.     

Mycotoxins in foods in Lower Saxony (Germany): results of official control analyses performed in 2009

In this presentation, the mycotoxin levels—as analysed by the analytical centre for mycotoxin surveillance of the state food laboratory (LAVES Braunschweig)—for approximately 500 food samples are reported. The samples were collected in the year 2009 at retail in the German federal state of Lower Saxony. Aflatoxin and ochratoxin A were analysed in dried fruits, spices, cereals and tree nuts. Ochratoxin A was detected in all samples of dried vine fruits, at levels up to 8.1 μg/kg. Aflatoxins and ochratoxin A were also found in nutmeg and curry powder: the maximum regulatory levels for aflatoxins were exceeded in 25% of the nutmeg samples. Nearly all samples of basmati rice contained aflatoxins, although at levels below the maximum regulatory level in all but one sample. Aflatoxins were also detected in about 50% of hazelnut samples, in 20% of the samples the maximum levels was exceeded (maximum 23.2 μg/kg). In contrast, aflatoxin contents in pistachios were surprisingly low. Fusarium toxins were analysed in cereals and cereal products such as flour, bread, and pasta. Deoxynivalenol (DON) was the predominant toxin found in these samples: DON was found in about 40% of the samples, although the maximum levels were not exceeded (max. 418 μg/kg). Fumonisins (FBs) and zearalenone (ZEA) were specifically analysed in maize products (snacks, flour and oil). Most of these samples (80%) were positive, but at levels not exceeding the maximum levels. Maximum levels were 98 μg/kg (ZEA) and 577 μg/kg (sum of FB₁ and FB₂). Ergot alkaloids (six major alkaloids) were analysed in rye flour, and approximately 50% were positive. The highest concentration of ergot alkaloids was 1,063 μg/kg; the predominant alkaloids were ergotamine and ergocristine. In conclusion, the results indicate that continuous and efficient control measures for mycotoxins in a wide range of critical foods are necessary to ensure compliance with maximum levels. Although the mycotoxin levels in the vast majority of samples were below maximum levels, year-to-year variation and changes in the production of relevant commodities may result in a different picture in the future.     

Fusarium toxins in cereals grown in Switzerland

770 cereal samples of Swiss origin which were collected in various feed mills and cereal collection centres in the years 2000 – 2002 were assayed for Deoxynivalenol (DON) and zearalenone (ZEA). 137 samples were also assayed for T-2 toxin. The prevalence of DON and ZEA contamination was higher in cereals harvested in the rainy summer 2002 than in the previous years. T-2 toxin levels exceeding 100 μg/kg were found only in three oats samples. High levels ofFusarium toxins do not frequently occur in Swiss cereals. Presented at the 25^th Mykotoxin Workshop in Giessen, Germany, May 19–21, 2003     

Trichothecenes and Mycoflora in Wheat Harvested in Nine Locations in Buenos Aires Province, Argentina

A total of 120 freshly harvested wheat samples from the 2004 season in nine locations from Northern Buenos Aires Province, Argentina, were analysed for trichothecene natural occurrence and associated mycoflora, and for determining the influence of commonly used fungicide field treatment and the cultivar type on trichothecene contamination. The trichothecenes T-2 tetraol, T-2 triol, HT-2 and T-2 toxin (HT-2, T-2), diacetoxyscirpenol (DAS), nivalenol (NIV), deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON) and 15-acetyldeoxynivalenol (15-ADON) were analysed by gas chromatography and electron capture detection. Detection limits ranged from 4 to 20 μg/kg. The isolation frequencies of species were calculated. Alternaria alternata, Fusarium graminearum, Fusarium poae and Fusarium semitectum were the predominant fungal species identified as endogenous mycoflora. The type of cultivar and the fungicide field treatment did not affect significantly the trichothecene contamination. The trichothecenes type A detected were HT-2 and T-2 triol toxins and the type B were DON, NIV and 3-ADON. Based on 120 samples the incidences were 21.7% for 3-ADON, 22.5% for HT-2, 27.5% for T-2 triol and 85% for DON. NIV was confirmed in one sample. Mean levels of trichothecene positive samples were between 7 and 2788 μg/kg.     

Mycotoxins and fungi in wheat harvested during 1990 in test plots in the state of São Paulo,Brazil

Wheat from two cultivars with contrasting characteristics were harvested in ten experimental plots located in wheat producing areas of the State of São Paulo, Brazil. The samples (10 of each cultivar) were analyzed by a gaschromatographic method for deoxynivalenol (DON), nivalenol (NIV), diacetoxyscirpenol (DAS), toxins T-2 (T-2) and HT-2, T-2 tetraol, T-2 triol, and by a thin-layer chromatographic method for zearalenone (ZEN), aflatoxins B₁, B₂, G₁, G₂, ochratoxin A and sterigmatocystin. No mycotoxins were detected in 13 samples. DON was found in four samples (0.47–0.59 µg/g), NIV in three samples (0.16–0.40 µg/g), T-2 in two samples (0.40, 0.80 µg/g), DAS in one sample (0.60 µg/g), and ZEN in three samples (0.04–0.21 µg/g). The wheat samples were also examined for the incidence of fungi.Alternaria, Drechslera, Epicoccum andCladosporium were the prevailing genera. Among theFusarium spp.,F. semitectum was present in 19 samples andF. moniliforme in 18 samples. NoF. graminearum was isolated in the samples.Abbreviations DAS diacetoxyscirpenol - DON deoxynivalenol - NIV nivalenol - T-2 T-2 toxin - ZEN zearalenone     

Determination of trichothecenes, zearalenone and zearalenols in commercially available corn-based foods in Spain

Among the main Spanish commercially available trademarks, we have selected a total of 25 samples of corn-based foods, which have the highest consume rate, to carry out the analysis of deoxynivalenol (DON), T-2 toxin, zearalenone (ZEA) and zearalenols (ZOL). The contents of mycotoxins were determined by gas chromatography with flame ionization detection, and those of ZEA were confirmed by HPLC with fluorescence detection. Of the 25 analyzed samples, the incidence of DON, ZEA and alfa-ZOL was 68, 44 and 24%, respectively; levels detected ranged from 29-195, 34-216, and 36-71 microg/kg, respectively. T-2 toxin was only detected in one sample (<50 microg/kg). Beta-ZOL was not present in excess of the detection limit in the investigated samples. The results suggest a risk for consumers of corn products and the need to monitor the final products before consumption. This is the first report in Spain on natural contamination with these mycotoxins in corn-based foods.     

Large-scale production of selected type A trichothecenes: the use of HT-2 toxin and T-2 triol as precursors for the synthesis of <Emphasis Type="Italic">d</Emphasis><Subscript>3</Subscript>-T-2 and <Emphasis Type="Italic">d</Emphasis><Subscript>3</Subscript>-HT-2 toxin

The type A trichothecenes T-2 and HT-2 toxins are toxic secondary metabolites produced by fungi of the Fusarium genus. Their occurrence in cereals, especially in oats, implies health risks for the consumer. Therefore, it is an important task to develop selective and sensitive methods for the analysis of T-2 and HT-2 toxins, and to undertake further studies on their stability and toxicity. Although most toxins are commercially available, their high prices are the limiting factor on the realization of these experiments. Thus, we developed a method for large-scale production of T-2 and HT-2 toxin as well as T-2 triol and T-2 tetraol. T-2 toxin was obtained in gram quantities by biosynthetic production with cultures of F. sporotrichioides. As HT-2 toxin was only formed as a by-product, and T-2 triol and T-2 tetraol were not generated, these compounds were produced by alkaline hydrolysis of T-2 toxin. Separation and isolation of crude toxins was achieved by fast centrifugal partition chromatography (FCPC), which is an efficient tool for the large-scale purification of natural products. Using this fast and yield effective technique, several hundred milligrams of HT-2 toxin, T-2 triol, and T-2 tetraol were obtained. Subsequent, HT-2 toxin and T-2 triol were used for the large-scale synthesis of isotope-labeled T-2 and HT-2 toxin, respectively. Using these standards, an isotope dilution-(ID)-HPLC-MS/MS method for the quantification of T-2 and HT-2 toxin in different matrices was developed.