Mycobiota in poultry feeds and natural occurrence of aflatoxins, fumonisins and zearalenone in the Rio de Janeiro State, Brazil

The intake of mycotoxin-contaminated feeds can lead to nutrient losses and may have adverse effects on animal health and on productivity. The aims of this study were (1) to determine the mycobiota present in poultry feed samples, and (2) to evaluate the natural occurrence of aflatoxin B₁, fumonisin B₁ and zearalenone. Fungal counts were similar between all culture media tested (10³ CFU g⁻¹). The most frequent genus isolated was Penicillium spp. (41.26%) followed by Aspergillus spp. (33.33%) and Fusarium spp. (20.63%). High precision liquid chromatography was applied to quantify aflatoxin B₁ and fumonisin B₁. Thin layer chromatography was used to determine zearalenone levels. Aflatoxin B₁ values ranged between 1.2 and 17.5 μg kg⁻¹. Fumonisin B₁ levels ranged between 1.5 and 5.5 μg g⁻¹. Zearalenone levels ranged between 0.1 and 7 μg g⁻¹. The present study shows the simultaneous occurrence of two carcinogenic mycotoxins, aflatoxin B₁ and fumonisin B₁, together with another Fusarium mycotoxin (zearalenone) in␣feed intended for poultry consumption. Many samples contained AFB₁ levels near the permissible maximum and it could affect young animals. A synergistic toxic response is possible in animals under simultaneous exposure.     

Fumonisins — Importance and occurence of a new group of mycotoxins

This paper describes the importance of fumonisins for human beings and animals and shows data for the occurence in food. Corn-based food samples (n = 299) purchased in the area of munich were analyzed for fumonisin content using an enzyme immunoassay. Fumonisins are mycotoxins produced byFusarium species, especially byFusarium moniliforme andFusarium proliferatum. Occurrence of fumonisins in corn and in cornbased foods and feeds has been reported from almost all over the world. In several animal species different diseases are traced back to fumonisin toxicosis. Fumonisin levels of 5–10 ppm inhorse feed induce “Equine Leucoencephalomalacia” and hepatic lesions. Hepatotoxic (10 150 ppm fumonisin in feed) and pneumotoxic (>150 ppm fumonisin in feed) effects have been reported for swine. Cattle and poultry appear to be less susceptible to fumonisins. Fumonisin B₁ Revels of 50 ppm in the diet of rats cause hepatotoxic and nephrotoxic effects, long time exposure results in hepatic cancer. A possible role of fumonisins in the etiology of human esophageal cancer is under discussion, although no direct causal evidence is known so far. The mode of action of the fumonisins is probably based on inhibition of sphingolipidbiosynthesis caused by the blockade of the enzyme sphyngosine (sphinganine)-N-acyltrans-ferase.     

Fungi,Aflatoxins, Fumonisin B<Subscript>l</Subscript> and Zearalenone Contaminating Sorghum-based Traditional Malt,Wort and Beer in Botswana

Brewing and consumption of traditional beer have social–economic significance in most African countries including Botswana. Traditional sorghum malt, wort, and beer samples were collected from three villages around Gaborone, Botswana. Forty-six malt samples were analyzed for fungi on three different media and developing colonies were subcultured for identification. Rhizopus, Fusarium, Mucor, and Aspergillus were the most common genera isolated. Out of the 46 malt samples, 72% contained Rhizopus stolonifer, 63% Fusarium verticillioides (syn. Fusarium moniliforme), and 37% Aspergillus flavus. Although Aspergillus flavus was isolated from malt samples, aflatoxins (B₁, B₂, G₁, and G₂) were not detected in any of the samples analyzed. When the malt, wort, and beer samples were analyzed for fumonisin B_l and zearalenone, fumonisin B₁ was detected in 3 malt samples, with concentrations ranging from 47 to 1316 μg/kg, while zearalenone was detected in 56%, 48% and 48% of the malt, wort and beer samples, respectively. Zearalenone concentration in samples ranged from 102 to 2213 μg/kg in malt, 26 to 285 μg/l in wort and 20 to 201 μg/l, in beer. Zearalenone carry-over from wort to beer ranged from 23 to 403%. Therefore, although aflatoxins and fumonisin B₁ do not appear to be major contaminants, zearalenone is common and could pose a potential problem in traditional beer in Botswana.     

Occurrence of fumonisins in maize imported into Iran during 2001–2002

Fumonisins, fungal toxins found primarily in maize and produced by various Fusarium species, have been shown to cause a variety of significant adverse health effects in livestock and experimental animals, and are probable human carcinogens. Thirty-three maize samples were collected at ports from bulk shipments, which were imported into Iran from six countries during 2001–2002, and analysed by HPLC for the most abundant of the naturally occurring fumonisin analogues, namely fumonisins B₁ (FB₁), B₂ (FB₂) and B₃ (FB₃). Of the 33 samples, 21 (64%) were found to contain FB₁ (58–512 μg/kg) at levels above 10 μg/kg. The frequency of FB₁ found in maize samples imported from Uruguay and Canada was 75%, followed by China and Argentina (67%), USA (60%), and Brazil (50%). The average FB₁ level was 266 and 169 μg/kg for positive and all samples, respectively. Medians were 250 and 146 μg/kg for positive and all samples, respectively. FB₂ levels ranged from not detected (<10 μg/kg) to 53 μg/kg, whereas no sample had an FB₃ level above the detection level (10 μg/kg). This is the first report of fumonisin contamination of imported maize in Iran. Although, the level of all detected fumonisins were below the Iranian and FDA tolerance levels for foods and feeds, It is necessary to maintain the strict rules to ensure continued safety of imported maize.     

Mycoflora and mycotoxins natural occurrence in corn from entre rios province, Argentina

Corn samples were collected in 1999 from three departments of Entre Réos province, Argentina, and were surveyed for mould contamination and natural occurrence ofFusarium mycotoxins, ochratoxin A and aflatoxins.Fusarium verticillioides was the most prevalent fungal species recorded at all departments. Zearalenone, deoxynivalenol and ochratoxin A were not found in any samples. Only one of the 52 corn samples analysed was contaminated with aflatoxin B₁ (17 μg/kg). Fumonisin B₁ was found in 58 % of samples (range of positive samples: 47– 3,347 μg/kg), fumonisin B₂ in 33.0 % (range of positive samples: 23–537 μg/kg) and fumonisin B₃ in 25.0 % (range of positive samples: 24–287 μg/kg) of them. This is the first report on the natural occurrence of mycotoxins in corn from Entre Ríos province, Argentina. Levels of fumonisins were lower than detected in other Argentinian provinces.     

Mycoflora and fumonisin-producing strains ofFusarium moniliforme in mixed poultry feeds and component raw material

In a survey of the mycoflora and mycotoxins in foods and feeds, 66 samples of mixed poultry feeds and some component raw materials were investigated. Fungal counts ranged from < 10² to 1.3 × 10⁶ CFU/g.Fusarium spp. counts ranged from 10² to 1.0 × 10⁶ CFU/g. TheFusarium spp. strains isolated were screened for their potential to produce fumonisin B₁ (FB₁) and fumonisin B₂ (FB₂) in maize cultures. Samples and maize cultures were analysed for FB₁ and FB₂ using TLC and fluorescamine-derivative HPLC. No fumonisins were detected in the samples (<6 ppm).Fusarium moniliforme was isolated in 59.1% of samples, and 97.4% of the strains produced FB₁ and 79.4% of strains produced FB₂ in maize cultures. Some isolates produced higher FB₁ and FB₂ levels than the reference strainF. moniliforme MRC 826.     

Mycotoxin Production by Fusarium proliferatum isolates from rice with Fusarium sheath rot disease

Twenty samples of unpolished (rough) rice collected in Arkansas and Texas during the 1995 harvesting season from fields exhibiting Fusarium sheath rot disease or panicle blight were previously shown to include 8 samples positive for fumonisin B₁(FB₁) in the range 2.2–5.2 ppm, and moniliformin (MON), but no beauvericin (BEA), deoxynivalenol, its derivatives or zearalenone were detected. Fifteen cultures of F. proliferatum were established from the 20 rough rice samples. Single spore isolates of each culture were grown on rice and tested for the production of fumonisins (FB₁, FB₂, FB₃, etc.), MON and BEA. All 15 isolates produced FB₁, FB₂, MON and BEA in culture on rice. No deoxynivalenol, its derivatives orzearalenone were detected. Seven cultures produced FB₁ at >50ppm (range 80–230 ppm), with therest producing FB₁ in the range 14–43 ppm.FB₂ was produced in the range 5–47 ppm, and those cultures which produced the most FB₁ also produced the most FB₂. Of the 15 cultures producing MON, 11 produced it at >100 ppm in the range 188–6018 ppm, with the rest producing in the range 7–64 ppm. BEA was produced in the range 109–1350 ppm. Other derivatives of fumonisins, including FA₁, FA₂ and partially hydrolyzed FB₁, as well asseveral unknown metabolites including a compound with MW 414, were identified in culture extracts by continuous flow fast atom bombardment with ion spraymass spectrometry (CF/FAB/MS). Further study is needed to identify the factors that control production of FB₁, MON and BEA by F.proliferatu in culture and in field samples. This revised version was published online in June 2006 with corrections to the Cover Date.     

Incidence of Fusarium spp. and Levels of Fumonisin B1 in Maize in Western Kenya

Maize kernel samples were collected in 1996 from smallholder farm storages in the districts of Bomet, Bungoma, Kakamega, Kericho, Kisii, Nandi, Siaya, Trans Nzoia, and Vihiga in the tropical highlands of western Kenya. Two-thirds of the samples were good-quality maize, and one-third were poor-quality maize with a high incidence of visibly diseased kernels. One hundred fifty-three maize samples were assessed for Fusarium infection by culturing kernels on a selective medium. The isolates obtained were identified to the species level based on morphology and on formation of the sexual stage in Gibberella fujikuroi mating population tests. Fusarium moniliforme (G. fujikuroi mating population A) was isolated most frequently, but F. subglutinans (G. fujikuroi mating population E), F. graminearum, F. oxysporum, F. solani, and other Fusarium species were also isolated. The high incidence of kernel infection with the fumonisin-producing species F. moniliforme indicated a potential for fumonisin contamination of Kenyan maize. However, analysis of 197 maize kernel samples by high-performance liquid chromatography found little fumonisin B₁ in most of the samples. Forty-seven percent of the samples contained fumonisin B₁ at levels above the detection limit (100 ng/g), but only 5% were above 1,000 ng/g, a proposed level of concern for human consumption. The four most-contaminated samples, with fumonisin B₁ levels ranging from 3,600 to 11,600 ng/g, were from poor-quality maize collected in the Kisii district. Many samples with a high incidence of visibly diseased kernels contained little or no fumonisin B₁, despite the presence of F. moniliforme. This result may be attributable to the inability of F. moniliforme isolates present in Kenyan maize to produce fumonisins, to the presence of other ear rot fungi, and/or to environmental conditions unfavorable for fumonisin production.     

Mycotoxin production by Aspergillus niger aggregate strains isolated from harvested maize in three Portuguese regions

BackgroundMaize is considered one of the crops more susceptible to mycotoxins in the world. Two of the mycotoxins commonly associated with maize are fumonisins and ochratoxin A. Aspergillus niger is a known producer of ochratoxin A and is easily found in maize. Recently, however, A. niger has been reported to produce as well fumonisins, mainly fumonisin B₂.AimsThe aim of this study was to isolate A. niger strains from maize samples collected in three Portuguese maize growing regions and to detect the production of both fumonisin B₂ and ochratoxin A.MethodsNinety five maize samples were collected, plated, and all observable Aspergillus section Nigri strains were isolated. Strains were morphologically characterized and mycotoxin production was determined by HPLC-FD.ResultsIsolations resulted in a total of 270 strains of black Aspergillus from 73 samples (77% of the samples). About 14% of those strains were found to produce ochratoxin A and 39% of the strains were found to produce fumonisin B₂.ConclusionsAn association between the production of these two mycotoxins could not be found and no conclusions could be taken whether the presence of A. niger aggregate strains will increase the risk of maize contamination with fumonisins and more specifically with fumonisin B₂.     

Natural occurrence of Fusarium species and fumonisin-production by toxigenic strains isolated from poultry feeds in Argentina

Fusarium species and fumonisin production by toxigenic strains were investigated. During 1996–1998, 158 samples of poultry feeds were collected from a factory located in the department of Río Cuarto Córdoba province, Argentina. The most common species of Fusarium were F. moniliforme (60.7%) and F. nygamai (35.4%) followed by F. semitectum, F. subglutinans, F. proliferatum, F. dlamini, F. solani, F. oxysporum and F. napiforme. Fungal counts ranged from 1 × 10³ to 8 × 10⁵ CFU/g with mean values from 1.5 × 10³ to 2.3 × 10⁵ CFU/g. The highest counts were for F. dlamini, F. subglutinans, F. moniliforme and F. nygamai. Strains of F. moniliforme, F. nygamai, and F. proliferatum were screened for their potential to produce fumonisin B₁ (FB₁), fumonisin B₂ (FB₂) and fumonisin B₃ (FB₃) in corn grain. The samples were analysed using a modified high performance liquid chromatography method. The strains assayed, 43 strains, produced three fumonisins. There was a high degree of variability in the quantities of FB₁, FB₂, and FB₃ produced. The toxin produced in highest levels by the majority of the strains was FB₁. The range of concentration varied from 5.4 to 3,991, 1.01 to 189 and 0.4 to 765 ppm per gram of corn for FB₁, FB₂ and FB₃ respectively. The toxigenic pattern of strains was normal, although two strains of F. moniliforme produced exceptionally high concentrations of FB₃ and minor concentrations of FB₂ and FB₁. This is the first report from Argentina on Fusarium species in poultry feeds and fumonisin production by these strains.This revised version was published online in October 2005 with corrections to the Cover Date.     

Trends of fumonisin contamination and animal intoxication through monitoring 1991 to 1997 corn crop in the State of Paraná, Brazil

Eleven feed samples associated with six animal (horse and poultry) intoxication outbreaks (1991) in the state of Paraná, Brazil, were evaluated for fungal and fumonisin contamination. In order to estimate the␣trend of livestock intoxication, fumonisin contamination was monitored in corn produced both at the commercial level (1991, 1995 crop), and in an experimental field at a local Agronomy Institute (1997 crop). The total mould count in the feed samples ranged from 2.9 × 10³ to 1.9 × 10⁷ CFU/g, with Fusarium verticillioides as the predominant species, at a high count of 2.4 × 10⁴–6.5 × 10⁵ CFU/g. Fumonisins (FB₁ + FB₂) were detected in all corn-based feed samples at levels ranging from 2.89 to 14.54 μg/g. All 27 Northern corn samples (1991 crop) were contaminated with fumonisins at levels ranging from 2.32 to 16.64 μg/g. Twenty-six (96.3%) out of 27 corn samples from the Central-Southern region (1995 crop) were positive for fumonisins (FB₁+FB₂), with the range of 0.07–3.66 μg/g, while all 37 Northern samples (1995 crop) were contaminated with fumonisins ranging from 0.57 to 9.97 μg/g. Twenty-one out of 37 corn samples from the Northern region (1997 crop) were positive for fumonisins, but at low level (range of 0.05–2.67 μg/g). The results showed a decreasing trend in fumonisin contamination over the years. Nowadays animal intoxication outbreaks rarely occur in this State, as both animal producers and feed industries have become conscious about monitoring of corn and other raw materials at the quality control level.     

Occurrence of Fumonisin B<Subscript>1</Subscript> in Corn from the Main Corn-Producing Areas of China

Fumonisin B₁ (FB₁) is the most abundant of the fumonisin mycotoxins, mainly produced in maize by F. verticillioides and F. proliferatum. A total of 282 corn samples harvested in 2005 from six provinces, the main corn-producing areas of China, were analyzed for FB₁ using high-performance liquid chromatography. All samples except one were (99.6%) positive for FB₁ at levels varying from 3 to 71,121 ng/g with mean and median levels for all samples of 6,662 and 1,569 ng/g, respectively. During an analysis of the distribution pattern for FB₁, it became apparent that 43.6% of tested samples had FB₁ concentrations below 1,000 ng/g, while 25.2% contained in excess of 5,000 ng/g. The average exposure to FB₁ (1.1 μg/kg body weight/day) is within the provisional maximum tolerable daily intake of 2 μg/kg body weight/day set by the Joint FAO/WHO Expert Committee on Food Additives.     

Occurrence of Fusarium Mycotoxin Fumonisin B1 and B2 in Animal Feeds in Korea

The objective of this study was to monitor the occurrence and levels of fumonisin B₁ (FB₁) and fumonisin B₂ (FB₂) in animal feeds distributed in South Korea in 2011. The contamination levels of FB₁ and FB₂ were investigated in 150 samples of compound feeds and in 40 samples of feed ingredients. The contamination rate of feed ingredients with FB₁ and FB₂ was 50 and 40 %, respectively. FB₂ was only found in samples contaminated with FB₁. Of the compound feeds, 85 % were contaminated by FB₁ and 47 % were contaminated by FB₂. The highest contamination rate of FBs was observed in compound feeds for cattle (FB₁: 100 %; FB₂: 80 %), followed by poultry feed (FB₁: 78 %; FB₂: 40 %) and swine feed (FB₁: 76 %; FB₂: 22 %). The highest contamination level (14,600 ng/g) for FB₁ were found in poultry broiler feed (early feeding period) samples, which had 82 % contamination rate (9/11), and the highest level of FB₂ (2,280 ng/g) was found in feed for fatting calves,which had a contamination rate of 100 %.     

Lymphocyte cytotoxicity and erythrocytic abnormalities induced in broiler chicks by fumonisins B1 and B2 and moniliformin fromFusarium proliferatum

Peripheral blood lymphocytes were isolated from broiler chicks that had ingested feed amended with autoclavedFusarium proliferatum culture material containing fumonisin B₁ (FB₁), fumonisin B₂ (FB₂) and moniliformin. Lymphocyte viability was determined for birds that were placed on amended rations at day 1 or day 7 of age at three different levels of mycotoxins, ranging from 61–546 ppm FB₁, 14–94 ppm FB₂ and 66–367 ppm moniliformin. Reduction of the tetrazolium salt, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide], to yield MTT formazan, based on mitochondrial metabolic activity, was used to assess cell viability. Lymphocyte cytotoxic effects were observed in all treatment groups on day 21; chicks that started on amended feed at day 1 of age were affected more than those that started at day 7. Abnormal erythrocytes resembling early stages of erythroblasts were observed in peripheral blood from test chicks. Abnormally shaped red cells (poikilocytes) having a spindle-shape with one or both ends pointed were present. Some red cells appeared to be undergoing mitosis. Both reduced lymphocyte viability and abnormal erythrogenesis occurred in chicks given feed amended withF. proliferatum culture material containing FB₁, FB₂ and moniliformin.     

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.     

Isolation of aflatoxigenic strains of Aspergillus and detection of aflatoxin B1 from feeds in India

In a preliminary study, 256 feed samples collected from different parts of Northern India were examined for the presence of aflatoxigenic strains of Aspergillus flavus/parasiticus and for detection of Aflatoxin B₁ (AFB₁). Out of 198 A. flavus and 15 A. parasiticus strains isolated, 76% and 86% respectively, were found to be toxigenic. Aflatoxin B₁ content of these feeds, as estimated by thin layer chromatography (TLC) and enzyme linked immunosorbent assay (ELISA) were very high (average 0.412 ± 0.154 ppm) in comparison to the permissible Indian regulation level (0.03 ppm). Seasonal variation of incidence and level of toxin in feed was recorded and it was high during monsoon/post monsoon period.This revised version was published online in October 2005 with corrections to the Cover Date.     

A survey of fumonisins (B1, B2, B3) in Indonesian corn-based food and feed samples

In this paper a survey is described for determination of contamination level of fumonisins (B¹, B², B³) in Indonesian cornbased feed and food samples. The survey was conducted from February to May 2001. Foodstuffs, which are consumed directly such as snacks and other products, were investigated for fumonisin contamination. Of 105 food and feed samples purchased from local retail stores and local poultry shops around Yogyakarta, Java, Indonesia were analyzed using ELISA. Results indicate that 74.3% of samples analyzed were contaminated in a large range of 10.0 – 3307 μg/kg, and the concentration of fumonisins depends on the type of samples. Detection limit of the method used was 9 μg/kg.From eight food samples of maize flour, and corn-based beverages and cereals, none was contaminated (below detection limit). For food samples of industrial products (19 samples), 13 were contaminated in the range of 22.8 – 105 μg/kg and 19 of 20 samples from home made products were contaminated between 12.9 – 234 μg/kg. The food samples contaminated in highest level occurred in corn. Of ten samples, 6 were contaminated from 68.0 – 2471 μg/kg. For feed samples, 17 corn samples were evaluated. Of those samples, 16 contained in a large range of 17.6 – 3306 μg/kg.     

Molecular Identification,Mycotoxin Production and Comparative Pathogenicity of Fusarium temperatum Isolated from Maize in China

A recently isolated Fusarium population from maize in Belgium was identified as a new species, Fusarium temperatum. From a survey of Fusarium species associated with maize ear rot in nineteen provinces in 2009 in China, ten strains isolated from Guizhou and Hubei provinces were identified as F. temperatum. Morphological and molecular phylogenetic analyses based on the DNA sequences of individual translation elongation factor 1‐alpha and β‐tubulin genes revealed that the recovered isolates produced macroconidia typical of four‐septate with a foot‐shaped basal cell and belonged to F. temperatum that is distinctly different from its most closely related species F. subglutinans and others within Gibberella fujikuroi complex species from maize. All the strains from this newly isolated species were able to infect maize and wheat in field, with higher pathogenicity on maize. Mycotoxin determination of maize grains infected by the strains under natural field condition by ultra‐high‐performance liquid chromatography–tandem mass spectrometry and gas chromatography–mass spectrometry analyses showed that among fifteen mycotoxins assayed, two mycotoxins fumonisin B₁ and B₂ ranging from 9.26 to 166.89 μg/g were detected, with massively more FB₂ mycotoxin (2.8‐ to 108.8‐fold) than FB₁. This mycotoxin production profile is different from that of the Belgian population in which only fumonisin B₁ was barely detected in one of eleven strains assayed. Comparative analyses of the F. temperatum and F. subglutinans strains showed that the highest fumonisin producers were present among the F. temperatum population, which were also the most pathogenic to maize. These results suggested a need for proper monitoring and controlling this species in the relevant maize‐growing regions.     

Effect of<Emphasis Type="Italic">in vitro</Emphasis> digestion on fumonisin B<Subscript>1</Subscript> in corn flakes

Low levels of fumonisins have been found frequently in corn based breakfast cereals and can occur bound to protein and other matrix components.In vitro digestion of two samples of corn flakes was carried out under "fed conditions." Fumonisins were measured as o-phthaldialdehyde/mercaptoethanol derivatives by LC-fluorescence. One sample of corn flakes (FN12) had high concentrations of fumonisin B₁ (FB) (average 125 ng/g) and total bound FB₁, (TB FB₁) (average 92 ng/g) and the other (FN11) had a low level of free FB₁ (average 29 ng/g) and no detectable TB FB₁. After incubation of the samples with gastrointestinal tract solutions simulating saliva plus stomach and duodenal juices, chyme was analysed for FB₁, hydrolyzed FB₁ (HFB₁) and partially hydrolyzed fumonisin B₁ (PHFB₁). The bioaccessibility (percentage of FB₁ released from corn flakes into chyme) was 38-78% for incurred FB₁ in FN12, 8-54% for incurred plus spiked FB₁ in FN12, and 19-66% for incurred plus spiked FB₁ in FN11. HFB₁ and PHFB₁ were not detected. If free FB₁ was first extracted from sample FN12, no FB1 was detected in the chyme, indicating no contribution from TB FB₁. Concentrations were corrected for method recovery of FB₁ or, for bound FB₁, partial method recovery of HFB₁ Presented at the XIIth IUPAC International Symposium on Mycotoxins and Phycotoxins, Istanbul, Turkey, 21–25 May, 2007     

Occurrence of Fumonisin in Forage Grass in New Zealand

Fumonisin B₁ (FB₁) was isolated from samples of forage grass originating in paddocks associated with an idiopathic disease of Canadian wapiti and wapiti-red deer hybrids characterized by “ill thrift” and liver dysfunction. Four of 40 samples contained 1, 3, 6, and 9 ppm (micrograms per gram) of FB₁ and 4, 0.5, 2, and 0.5 ppm, respectively, of the methyl ester of FB₁. Analyses were done by ion spray mass spectrometry and confirmed by both fast atom bombardment (solids probe) and mass spectral analysis by electron impact ionization of the trifluoroacetate derivative of the base hydrolyzed product (pentolamine) of FB₁. This article contains the first report of the presence of fumonisin B₁ in grass.