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This study explores the implementation of the One Sample Strategy (OSS), a co-regulation program aimed at managing mycotoxin risk in Texas maize. Fumonisin-contaminated cereals and oilseeds that contain greater than 5 mg kg -1 of the toxin (B 1 , B 2 , and B 3 ) are a risk for equids and rabbits, and levels greater than 60 mg kg -1 are a risk to ruminants. The OSS, previously successful in managing aflatoxin risk in Texas maize, was evaluated for its effectiveness in handling fumonisin risk in maize, specifically as it relates to ruminants. In 2017, 25 analysts across seven firms qualified to participate in the program. To ensure greater accuracy in testing, working control samples were provided to the participating OSS firms with the requirement that their results fall within +/- 20% of the target concentration. Ninety-four percent of the working controls met this specification. The capability to grind maize to the OSS prescribed particle size was met by 100% of participants. To verify testing accuracy, file samples collected from each OSS firm were analysed by UPLC-MS/MS. The 177 fumonisin verification samples analysed by Office of the Texas State Chemist (OTSC) were correlated ( r  = 0.93) with co-regulation laboratories. Results were plotted in an operating curve to depict type I and type II errors. Error analysis revealed a type I error rate of 13% and type II error rate of 2% for the 5 mg kg -1 guidance level, and 6% and 8%, respectively, for the 60 mg kg -1 guidance level. For 2017, 994 official reports of analysis for fumonisin in whole maize in the Texas High Plains were issued by the seven laboratories that employed 25 OTSC-credentialed analysts. The OSS co-regulation program, supported by a quality systems approach and government regulations, has proven effective in managing fumonisin risk in Texas maize, enhancing both market confidence and livestock safety.

This review analyzes the occurrence and co-exposure of aflatoxins and fumonisins in conventional and organic corn, and compares the vulnerability to contamination of both. The risks of fungal contamination in corn are real, mainly by the genera Aspergillus and Fusarium , producers of aflatoxins and fumonisins, respectively. Aflatoxins, especially AFB 1 , are related to a high incidence of liver cancer, and the International Agency Research of Cancer (IARC) classified them in group 1A 'carcinogenic to humans'. The occurrence in conventional corn is reported in many countries, including at higher levels than those established by legislation. IARC classified fumonisins in group 2B 'possibly carcinogenic to humans' due to their link with incidence of esophageal cancer. However, comparing corn and organic and conventional by-products from different regions, different results are observed. The co-occurrence of both mycotoxins is a worldwide problem; nevertheless, there is little data on the comparison of the co-exposure of these mycotoxins in corn and derivatives between both systems. It was found that the agricultural system is not a decisive factor in the final contamination, indicating the necessity of effective strategies to reduce contamination and co-exposure at levels that do not pose health risks.

Fumonisins are one of the main problems affecting maize production in the Texas High Plains (THP), where its agroclimatic conditions make it a perennial hotspot for mycotoxin contamination. In 2017, a fumonisin outbreak in the THP maize motivated stakeholders' request to repeal a subsection of the Texas Administrative Code, §61.61(a)(7) (Fumonisin Rule), and its related Texas Feed Industry Memorandum (Memo 5-20), which previously permitted the blending of maize containing high fumonisin levels with maize containing ≥ 5 mg/kg under state authority, and pivot to FDA fumonisin guidance. Shortly after, the USDA Risk Management Agency (RMA's) reintroduced Discount Factors (DFs) in annual Special Provisions (SP) that outline price reductions related to fumonisin contamination in maize. In this research, we estimate the potential economic burden posed by these changes through a two-part approach. In part one, we construct a decision model that explores the final disposition of fumonisin-contaminated maize based on blending permissions, fumonisin levels, and crop insurance status. In part two, we estimate the economic impact by inserting output values of the decision model into financial equations that consider testing costs, transportation fees, and discounts from crop insurance and grain elevators when applicable. Our economic analysis projects that the financial losses during a THP crop year with high fumonisin levels could range from $15.1 to $135.5 million without the option to blend under conditions of the revised RMA discount schedule. Findings further highlight crop insurance as the most promising risk management strategy for farmers in areas susceptible to fumonisin contamination.

This study reports levels of mycotoxins in sorghum from Niger State, Nigeria, and provides a comprehensive assessment of their potential health risks by combining mycotoxin levels and dietary exposure assessment. A total of 240 samples of red and white sorghum were collected from both stores and markets across four microclimatic zones. Fungal species were identified using a dilution plate method. Aflatoxins (AFs), deoxynivalenol, nivalenol, and ochratoxin (OTA) were quantified using HPLC, whereas cyclopiazonic acid, fumonisins (FUMs) and zearalenone were quantified using ELISA. A. flavus and A. fumigatus were dominant fungal species followed by F. verticilloides , A. oryzae and P. verrucosum . Aflatoxins (mean: 29.97 µg/kg) were detected in all samples, whereas OTA (mean: 37.5 µg/kg) and FUMs (mean: 3269.8 µg/kg) were detected in 72% and 50% of the samples, respectively. Mycotoxins frequently co-occurred in binary mixtures of AFs + OTA and AFs + FUMs. Dietary exposure estimates were highest for FUMs at 230% of TDI and margin of exposures (MOEs) for both AFs and OTA (<10,000) indicating a potential risk associated with combined exposure to AFs and OTA. The Risk of hepatocellular carcinoma cases (HCC/year) attributable to AFs and OTA exposure from sorghum was estimated to be 5.99 × 10 5 and 0.24 × 10 5 cases for HBsAg + individuals based on 13.6% HBV incidence. Similarly, the HCC/year for AFs and OTA were assessed to be 3.59 × 10 5 and 0.14 × 10 5 at an 8.1% prevalence rate. Therefore, the results of this study demonstrate the high prevalence and dietary exposure to mycotoxins through sorghum consumption, raising public health and trade concerns.

We have previously published six esterified O -acyl (EFB1) and three N -acyl fumonisin B 1 derivatives extracted from rice cultures inoculated with Fusarium verticillioides , amongst these the identification of N -palmitoyl-FB1 has been clearly established in a spiking experiment. At that time, it was assumed that as in the case of O -acyl-FB1 derivatives, linoleic-, oleic- or palmitic acid esterify through the OH group on the 3C or 5C atom of the carbon chain of the fumonisins. In our most recent experiments, we have synthetically acylated the FB1 toxin and subsequently purified 3- O -palmitoyl- and 5- O -palmitoyl-FB1 toxins in addition to the N -palmitoyl-FB1 toxin. They were identified and characterised using 1 H and 13 C NMR as well as LC-HRMS. Our aim was the identification of the previously detected O -acyl-FB1 derivatives over the course of a spiking experiment, which were obtained through the solid-phase fermentation of Fusarium verticillioides . By spiking the three synthesized and identified components one-by-one into the fungal culture extract and analysing these cultures using LC-MS, it was clearly demonstrated that the F. verticillioides strain produced both the 5- O -palmitoyl-FB1 and N -palmitoyl-FB1 toxins, but did not produce 3- O -palmitoyl-FB1. Thus, it is highly probable that the components thought to be 3- O -acyl-(linoleoyl-, oleoyl-, palmitoyl-) FB1 derivatives in our previous communication are presumably 10- O -acyl-FB1 derivatives. Since these acylated FB1 derivatives can occur naturally in e.g. maize, the use of these synthesized components as reference materials is of great importance in order to obtain accurate qualitative and quantitative data on the occurrence of acylated fumonisins in different matrices including maize based feed samples. The production of these substances has also made it possible to test their toxicity in cell culture and small animal experiments.

This paper demonstrates the development of an analytical method based on CE coupled to ESI-MS for the identification and quantification of fumonisin mycotoxins. Separation and detection parameters (pH of background electrolyte (BGE), organic modifier content, sheath liquid (SL) composition, MS mode and nebuliser pressure) were optimised. Ammonium formate/ammonia (pH = 9.5) with 10% ACN modifier was found the most suitable BGE. Positive mode MS was used for detection by scanning the m/z range of 400-1200. Separation was highly affected by the nebuliser pressure, a 25% improvement in peak resolution was achieved by applying the optimised parameters. The 'dilute and shoot' approach was applied to overcome disturbing effects caused by the matrix of fungi supernatant samples. The available sample volume affected the reproducibility of the measurements greatly: the scattering of peak intensities were between 4 and 11 RSD% instead of 27-195 RSD% for fumonisin B 1 and fumonisin B 2 when the available volume was ~200 µL instead of ~20 µL. Quantitative determinations were carried out in Fusarium verticillioides and Fusarium proliferatum culture supernatant (raw) and mycelium (cleaned up) samples. The optimised method enabled the detection of 11 fumonisins in Fusarium proliferatum inoculated rice samples; 2 of them were quantified based on external calibration and 4 other compounds with fumonisin-like formulas were detected.

This study aimed to assess aflatoxin and fumonisin intake through corn tortilla consumption in Veracruz city. Between October 2013 and February 2015, a total of 120 corn tortilla samples (2 kg samples, 40 samples per year) were randomly collected. Aflatoxins and fumonisins were quantified by high performance liquid chromatography coupled with a fluorescence detector. A probability density function (PDF) was used for describing corn tortilla intake, body weight of the Veracruz city population, mycotoxin content of corn tortilla samples and estimated mycotoxin daily intake. The Monte Carlo method with 10,000 iterations was employed to assess the population exposure risk. The highest level of total aflatoxins (AFT) was 22.17 μg kg -1 , and 526.6 μg kg -1 for fumonisins B 1 plus B 2 , with 85% and 90% of contaminated samples respectively. Up to 69.7 % of the population was estimated to consume a higher aflatoxin dose than that recommended by the JECFA (1 ng kg -1 of body weight per day); it was found that the recommended dose was exceeded to a greater extent in the male population, due to higher consumption of corn. The risk of fumonisin intake was less than 5 % due to the low presence and levels of these toxins in corn tortillas. The results suggest that corn tortilla consumers are at dietary risk caused by AFT contamination; this information should be considered when taking action to protect public health.

Consumption of fumonisin-contaminated foods has a negative influence on the health of humans (carcinogen; oesophageal cancer in Eastern Cape in South Africa). Lactic acid bacteria (LAB) have emerged as a promising natural detoxification agent against mycotoxins. The aim of this study was to visualise the interaction between fumonisins (FB 1 and FB 2 ) and LAB: Lactobacillus plantarum FS2, L. delbrueckii subsp. delbrueckii CIP 57.8T and Pediococcus pentosaceus D39, isolated from traditional fermented maize-based products (ogi and mahewu) using confocal laser scanning microscopy (CLSM) and to then quantify the LAB-bound fumonisin using high performance liquid chromatography (HPLC). The objective was to obtain a physically visible and quantifiable binding interaction between fumonisins and LAB strains with the aim of utilising LAB as a possible detoxifying agent. Fumonisins were derivatised using naphthalene-2,3-dicarboxaldehyde (NDA) and then combined with non-fluorescent LAB cells (viable and non-viable). For the quantification of bound fumonisins, viable and non-viable cells were incubated in the presence of predetermined concentrations of fumonisins and the level of fumonisin in the suspension was determined. CLSM showed the derivatised green fluorescent fumonisins binding to the surface of each of the LAB cells. For viable cells, L. plantarum FS2 bound FB 1 most effectively while P. pentosaceus D39 bound the least level of FB 1 . The highest levels of FB 2 were bound by L. plantarum R 1096 and the least by L. delbrueckii CIP 57.8 T. For non-viable cells, L. plantarum FS2 was also the most effective for binding both fumonisins with P. pentosaceus D39 and L. delbrueckii CIP 57.8 T being the least effective for FB 1 and FB 2 , respectively. To our knowledge, this is the first study to visualise the interaction between LAB and fumonisins. We demonstrate that LAB isolates from indigenous fermented maize-based beverages bind fumonisins and thus present a potential strategy for their reduction in these traditional foods.

One of the food security problems faced worldwide is the occurrence of mycotoxins in grains and their foods. Fumonisins (FBs) are mycotoxins which are prevalent in corn (Zea mays L.) and its based foods. Their intake and exposure have been epidemiologically and inconclusively associated with oesophageal cancer and neural tube defects in humans, and other harmful health effects in animals. The toxic effects of FBs can be acute or chronic and these metabolites bioaccumulate mainly in liver and kidney tissues. Among FBs, fumonisin B 1 (FB 1 ) is the most relevant moiety although the 'hidden' forms produced after food thermal processes are becoming relevant. Corn is the grain most susceptible to Fusarium and FBs contamination and the mould growth is affected both by abiotic and biotic factors during grain maturation and storage. Mould counts are mainly affected by the grain water activity, the environmental temperature during grain maturation and insect damage. The abiotic factors affected by climatic change patterns have increased their incidence in other regions of the world. Among FBs, the hidden forms are the most difficult to detect and quantify. Single or combined physical, chemical and biological methods are emerging to significantly reduce FBs in processed foods and therefore diminish their toxicological effects.

This paper presents data on the occurrence of Fusarium toxins - zearalenone (ZEA), deoxynivalenol (DON) and fumonisins (FUMs) B1 and B2 - in corn flours and corn flakes marketed in Serbia. A total of 71 samples were collected over 2013-2016 and analysed using HPLC with UV or fluorescence detection. In the case of corn flours, none of the samples taken in 2013 exhibited the presence of ZEA or DON, whereas 90% were positive for FUMs. In 2015, occurrence was very high: ZEA 93%, DON 86% and FUMs 100% (mean 43.3, 322.6 and 323.0 μg kg -1 , respectively), with 21% of the samples exceeding the maximum level for ZEA and 7% for DON and FUMs. In 2016, a lower occurrence was recorded in the case of ZEA (75%) and DON (38%), with drastically lower mean contamination levels (six- and 10-fold, respectively), while FUMs stayed at 97%, with twofold lower mean. The maximum level was exceeded only for ZEA (3%). The frequency of ZEA-DON-FB1 co-occurrence was 86% in 2015 and 25% in 2016. Regarding corn flakes, occurrence summarised for the study period was 87% ZEA, 73% FUMs and 40% DON. One sample (7%) exceeded the maximum levels for both ZEA and DON. Observed occurrence changes were in agreement with the climatic conditions during corn growing seasons preceding the market release of the processed products.

Maize is most often infected by the fumonisin-producing Fusarium verticillioides. Total fumonisins of natural infected grain is made up of FB 1 , FB 2 and FB 3 with FB 1 occurring naturally at higher levels. A maize plant can be infected with more than one F. verticillioides isolate, and finding a reliable method to elucidate the toxigenic potential of these isolates is important to extrapolate the possible fumonisin risk to consumers of grain. It is not clear whether F. verticillioides produces similar fumonisin levels, as well as fumonisin analogue ratios, across media. In this study, nine F. verticillioides isolates were subjected to three methods of fumonisin testing using liquid media, maize patties and a field trial (silk inoculation of grain) in Potchefstroom, South Africa. Spore concentrations of 1 × 10 6 conidia ml - 1 of each isolate were used to inoculate the different media and levels fumonisin analogues were measured using HPLC. Fumonisin production per isolate was highly variable and was influenced by the two-way interaction of F. verticillioides isolate × growth media. Total fumonisins produced in the liquid medium ranged from 0 to 21.3 ppm, on maize patties fumonisins they ranged from 0 to 21.5 ppm, and in the silk inoculation technique they ranged from 0 to 15.5 ppm. The fumonisin analogue FB 1 occurred at higher levels followed by FB 3 in both in vitro studies. In the silk inoculation technique, fumonisin analogue FB 2 was the second highest occurring analogue after FB 1 . Isolate GCI 282 produced higher FB 2 and FB 3 levels than FB 1 in the patties and grain, respectively. In order not to miscalculate the fumonisin and analogue ratio levels per F. verticillioides isolate, the growth medium will have to be optimised for each isolate and more than one growth medium used.

A sensitive immunochromatographic assay (ICA) using a colloidal gold-antibody probe for the rapid detection of fumonisin B1 (FB1) in corn samples was developed. The colour density of the test line correlated with the concentration of FB1 in the range 2-40 ng ml(-1) by the assay, and the detection limit for FB1 was 2 ng ml(-1). The linear range for FB1 was 50-1000 µg kg(-1), and the visual limit detection of the test was 1000 µg kg(-1) in corn samples. The ICA to detect FB1 is sensitive, specific and rapid. Specific anti-FB1 monoclonal antibody (mAb) and FB1-ovalbumin (FB1-OVA) conjugate antigen were prepared. FB1 mAb, labelled with colloidal gold, was used as the probe on the immunochromatographic strip. FB1-OVA and goat-anti-mouse IgG were coated onto a nitrocellulose (NC) membrane as test lines and control lines, respectively. FB1 in samples will competitively combines the FB1 mAb with the FB1-OVA in an NC membrane and the results are directly observed by the colour of the detection and quality control lines. The concentrations of FB1 mAb labelled with colloidal gold, detecting antigen and goat anti-mouse IgG, were optimised. The results indicate that the test strip is specific for FB1, with no cross-reactivity to other toxins. The strip assay for FB1 was simple, only needing one step without complicated assay performance and expensive equipment, and the total time for visual evaluation was less than 10 min. A survey of 24 corn samples from Hefei, China, was performed with the test strip and HPLC, and the detection results showed that the developed ICA and the HPLC were in excellent agreement. Hence, the developed ICA can be used as a method for rapid detection of FB1 in corn samples.

In vitro experimental environments are used to study interactions between microorganisms, and to predict dynamics in natural ecosystems. This study highlights that experimental in vitro environments should be selected to match closely the natural environment of interest during in vitro studies to strengthen extrapolations about aflatoxin production by Aspergillus and competing organisms. Fungal competition and aflatoxin accumulation were studied in soil, cotton wool or tube (water-only) environments, for Aspergillus flavus competition with Penicillium purpurogenum, Fusarium oxysporum or Sarocladium zeae within maize grains. Inoculated grains were incubated in each environment at two temperature regimes (25 and 30°C). Competition experiments showed interaction between the main effects of aflatoxin accumulation and the environment at 25°C, but not so at 30°C. However, competition experiments showed fungal populations were always interacting with their environments. Fungal survival differed after the 72-h incubation in different experimental environments. Whereas all fungi incubated within the soil environment survived, in the cotton wool environment none of the competitors of A. flavus survived at 30°C. With aflatoxin accumulation, F. oxysporum was the only fungus able to interdict aflatoxin production at both temperatures. This occurred only in the soil environment and fumonisins accumulated instead. Smallholder farmers in developing countries face serious mycotoxin contamination of their grains, and soil is a natural reservoir for the associated fungal propagules, and a drying and storage surface for grains on these farms. Studying fungal dynamics in the soil environment and other environments in vitro can provide insights into aflatoxin accumulation post-harvest.

Dietary exposure of Hong Kong adults to mycotoxins and their metabolites including aflatoxins (AFs), ochratoxin A (OTA), fumonisins (FNs), deoxynivalenol (DON), acetyldeoxynivalenols (AcDONs) and zearalenone (ZEA) was estimated using the Total Diet Study (TDS) approach to assess the associated health risk to the local people. Sixty commonly consumed food items, collected in four seasons, were sampled and prepared as consumed. These mycotoxins were primarily found at low levels. The highest mean levels (upper bound) were: AFs, 1.50 µg kg(-)(1) in legumes, nuts and seed; OTA, 0.22 µg kg(-)(1) in sugars and confectionery; FNs, 9.76 µg kg(-)(1) in cereals and their products; DON and AcDONs, 33.1 µg kg(-)(1) in cereals and their products; and ZEA, 53.8 µg kg(-)(1) in fats and oils. The estimated dietary exposures of Hong Kong adults to the mycotoxins analysed were well below the respective health-based guidance values, where available. For AFs, the upper-bound exposure for high consumers is 0.0049 µg kg bw(-)(1) day(-)(1), which was estimated to contribute to about 7.7 (< 1%) of liver cancer cases when compared with 1222 liver cancer cases per year in Hong Kong. The percentage contributions of the estimated 95th percentile dietary exposures (lower and upper bound) to the health-based guidance values of individual mycotoxins were: ochratoxin A, 3.6-9.2%; fumonisins, 0.04-8.5%; deoxynivalenol and acetyldeoxynivalenols, 21.7-28.2%; and zearalenone 3.3-34.5%. The findings indicate that dietary exposures to all the mycotoxins analysed in this study were unlikely to pose an unacceptable health risk to the Hong Kong population.

The effect of water activity (aw = 0.95, 0.98 and 0.995), temperature (15, 25 and 30°C), incubation time (7, 14, 21 and 28 days), and their interactions on growth and moniliformin (MON), beauvericin (BEA), fusaproliferin (FUS) and fumonisin B1 (FB1) production by two strains of Fusarium temperatum isolated from Argentinean maize were determined in vitro on sterile layers of maize grains. The results showed that there was a wide range of conditions for growth and mycotoxins production by F. temperatum. Both strains were found to grow faster with increasing aw and at 30°C. In relation to mycotoxin production, the two strains produced more FUS than the other mycotoxins regardless of aw or temperature evaluated (maximum = 50,000 μg g(-1)). For FUS, MON and BEA, the maximum levels were observed at 0.98 aw and 30°C (50,000, 5000 and 2000 μg g(-1) respectively). The lowest levels for these three mycotoxins were detected at 15°C and 0.95 aw (1700 and 100 μg g(-1) for FUS and MON respectively), and at 0.98 aw (400 μg g(-1) for BEA). The maximum levels of FB1 were produced at 15°C and 0.98 aw (1000 μg g(-1)). At all aw and temperatures combinations evaluated there was an increase in toxin concentrations with time incubation. The maximum levels were detected at 21 days. Statistical analyses of aw, temperature, incubation time, and the two- and three-way interactions between them showed significant effects on mycotoxins production by F. temperatum. For its versatility on growth and mycotoxin production, F. temperatum represents a toxicological risk for maize in the field and also during grain storage.

A survey was undertaken of a total of 120 farmers, 40 from each of the three studied agro-ecological zones of Tanzania, to determine local post-harvest management practices associated with aflatoxin (AF) and fumonisin (FB) contamination of maize. Data on practices (collected using a structured questionnaire) and maize samples were obtained from each of the 120 farmers. FB and AF contamination in the samples were analysed by HPLC. A total of 45% and 85% of maize samples were positive for AF and FB respectively, with levels ranging from 0.1 to 269 μg kg(-1) for AF and from 49 to 18 273 μg kg(-1) for FBs. Significant differences in contamination level were observed among the three agro-ecological zones. Farmers in the three agro-ecological zones practised similar practices in varying degrees. Drying, sorting and protecting maize against insect infestation are practices that showed significant association with AF or FB contamination of maize. Drying maize on mat/raised platform, sorting (damaged, discoloured and moulded grains) and application of synthetic insecticides during storage are practices that were associated with less contamination of maize with AF and FB. The results can be used to advise on effective post-harvest strategies for prevention of AF and FB contamination of maize in rural Tanzania.

The distribution of fumonisins (FBs: FB1 and FB2) in the corn-milling process and in corn-based products, as well as daily intake estimates for the Brazilian population were evaluated. Among corn fractions samples, corn meal had the highest mean concentration of FB1 (1305 µg kg(-1)) and FB2 (651 µg kg(-1)) and a distribution factors of 452% and 256% in relation to corn grain, respectively. On the other hand, the distribution factor of FB1 and FB2 in corn flour was found to be 144% and 88% respectively, which demonstrates that fumonisins in this fraction were reduced compared with corn grain. As a result, almost half the corn meal samples (47%) would be non-compliant with future Brazilian regulation (2017) for fumonisins. However, corn-based products, such as corn flakes and popcorn, were in compliance with the regulation. The average probable daily intake and maximum probable daily intake of fumonisins estimated for the Santa Catarina state (Brazil) population were below the provisional maximum tolerable daily intake of 2 µg kg(-1) body weight day(-1) for all corn samples. Despite this, the adoption of practices to control the occurrence of fumonisins should be applied to the corn-milling fractions that may contain a higher concentration of this toxin, such as corn meal, often used for animal feed in Brazil.

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 species, which can produce mycotoxins, are the predominant pathogens causing maize ear rot, a disease that results in severe economic losses and serves as a potential health risk for humans and animals. A survey was conducted in 2012 to investigate the contamination of maize by Fusarium species and fumonisins B1 and B2. A total of 250 maize samples were randomly collected from nine provinces (Hebei, Shanxi, Inner Mongolia, Yunnan, Sichuan, Guizhou, Heilongjiang, Liaoning and Ningxia) in China. Fusarium species were isolated and identified using morphological (electron microscope) and molecular methods (polymerase chain reaction (PCR) and sequencing). Fumonisins B1 and B2 were analysed using high-performance liquid chromatography with fluorescence detection (HPLC-FLD) with OPA (2-Mercaptoethanol, o-phthaldialdehyde) post-column derivatisation. A total of 2321 Fusarium isolates (20.7%) were obtained from all the samples. These isolates included nine Fusarium species, namely, F. graminearum, F. verticillioides, F. subglutinans, F. proliferatum, F. temperatum, F. oxysporum, F. equiseti, F. meridionale and F. chlamydosporum. The incidence of occurrence of Fusarium species in Guizhou was the highest, while in Inner Mongolia it was the lowest. F. verticillioides was the dominant species of maize ear rot in Liaoning, Sichuan, Hebei and Ningxia. F. graminearum was the dominant species in Yunnan, Guizhou and Shanxi. F. subglutinans was the dominant species in Heilongjiang. F. verticillioides and F. graminearum percentages were the same in Inner Mongolia. The incidence of fumonisins in Liaoning was high (up to 81.0%) and in Heilongjiang low (up to 10.3%). Except Shanxi, more than 50% of maize samples from other provinces were contaminated with fumonisins, with concentrations less than 500 ng g(-1). About 33% of maize samples from Yunnan were contaminated with high levels of fumonisins, and average of fumonisin levels were 5191 ng g(-1). Fusarium species causing maize ear rot in different areas in China were highly diverse and such areas with exposure to high levels of fumonisin contamination have a potential health risk for human and animals.

Traditional and improved varieties of maize, pearl millet and sorghum were planted by small-scale farmers under the direction of the International Institute for Tropical Agriculture in two Nigerian agro-ecological zones: the Sudan Savanna and the Northern Guinea Savanna. Samples were collected for the determination of Fusarium infection and fumonisin (B1, B2 and B3) contamination. A previous paper reported Aspergillus infection and aflatoxin contamination of these samples. Fusarium infection levels, measured by per cent kernels infected, were modest with mean levels for the above cereals of 16% ± 11% (SD), 12% ± 7% and 13% ± 16%, respectively. However, the Fusarium species recovered from maize were predominantly the fumonisin producers F. verticillioides and F. proliferatum, together making an infection rate of 15% ± 10%, whereas these species were present to a limited extent only in the other two cereals, 1% ± 1% for pearl millet and 2% ± 6% for sorghum. Fumonisin contamination was variable but reflected the diversity of Fusarium producers in these three cereals. Mean levels were 228 ± 579 µg kg(-1) (range < 5-2860 µg kg(-1)) for maize, 18 ± 7 µg kg(-1) (range = 6-29 µg kg(-1)) for pearl millet and 131 ± 270 µg kg(-1) (range < 5-1340 µg kg(-1)) for sorghum. Together with previous results on aflatoxin, this study confirmed the co-occurrence of aflatoxins and fumonisins in maize as well as in the traditional African cereals, millet and sorghum (89% co-occurrence across all three cereals). The low fumonisin levels may be ascribed to the use of good agricultural practices. Of the Fusarium species present, those in maize consisted mainly of fumonisin producers, the opposite of what was observed in pearl millet and sorghum. It is concluded that replacement of maize by pearl millet and sorghum could improve food safety with regards to aflatoxin B and fumonisin B exposure.

Fusarium toxins with reference to fumonisin B1 (FB1) have long been regarded as contaminants of maize and maize-based related products. However, when consumed they can cause intoxication, especially in humans. Therefore, effective quantitative methods for assessing the dietary exposure of this toxic fungal metabolite are required. The objective of this investigation was to evaluate the effect on the use of a bio-wipe kit, which is a faecal material collection kit, to detect the presence of FB1. Faecal materials were collected from a rural farming community in Gauteng Province, South Africa. In total, 200 samples of faecal material were analysed for Fusarium species using a serial dilution method, while FB1 was further analysed and quantified by reversed-phase TLC and HPLC. The study showed the presence of 11 different Fusarium species grown on potato dextrose agar culture medium of which F. verticillioides and F. proliferatum, producers of FB1, and F. oxysporum were the dominant species. Fumonisin B1 was recorded at an incidence rate of 65% of the total using TLC. Results from HPLC showed that 84% were positive at different ranges of concentration for FB1. This study supports the use of a bio-wipe as a rapid method to determine human exposure to FB1.

Fusarium is a globally distributed fungal genus that includes different species pathogenic to cereals among others crops. Some of these Fusarium species can also produce toxic compounds towards animals and humans. In this work, the presence of the most important Fusarium toxins was determined in barley seeds from Spain, sampled according to European Union requirements. The results obtained were compared with the presence of mycotoxigenic species considered responsible for their synthesis by using species-specific polymerase chain reaction protocols. Fumonisins B(1) and B(2), zearalenone, trichothecenes type A (T-2 and HT-2) and trichothecenes type B (deoxynivalenol and nivalenol) were analysed by using high-performance liquid chromatography. Deoxynivalenol and zearalenone were detected in 72% and 38% of the barley samples, respectively, at levels below European Union limits in all cases. However, the co-occurrence of both toxins in 34% of the samples suggested that synergistic activity of these two mycotoxins should be evaluated. Nivalenol and HT-2/T-2 were detected at low levels in 17% and 10% of the samples, respectively. Fumonisins occurred in 34% of the samples at levels up to 300 µg/kg. This suggested that they might represent a risk in Spanish barley, and to our knowledge, this is the first report on the presence of fumonisins in barley in this country. The species-specific polymerase chain reaction assays to detect mycotoxin-producing Fusarium species showed a very consistent correlation between F. verticillioides detection and fumonisin contamination as well as F. graminearum presence and zearalenone, deoxynivalenol and nivalenol contamination in barley samples. The approach used in this study provided information of mycotoxin contamination of barley together with the identification of the fungal species responsible for their production. Detection of the species with the current polymerase chain reaction assay strategy may be considered predictive of the potential mycotoxin risk in this matrix.

Fumonisins are mycotoxins produced by the Fusarium group of fungi commonly found on crops, mainly on maize. Some data suggest that as much as 25% of world crops may be lost because of mycotoxin contamination. Therefore, researchers in many countries (particularly in those in which relatively large amounts of maize are directly consumed by humans) are concerned with fumonisin levels in plant-origin foodstuffs and feeds available in their local markets. There is no doubt the levels are strongly correlated with the climate conditions prevailing in the region in which the maize was cultivated: the hotter the climate, the more serious the problem. Negative consequences of consumption of fumonisin-contaminated food by humans include an increased risk of oesophagus cancer and decreased body mass growth. In recent years some trials have been undertaken to reduce fumonisin levels in food and feed by the application of isothiocyanates naturally occurring in plants or peptidoglycans isolated from lactic acid bacteria (LAB). The results of these studies suggested that some reduction in contamination levels might be achieved. Additionally, some recent studies indicate that Sphingopyxis sp. bacteria produce enzymes that are able to break down the fumonisin molecule. Some fumonisins present in food may be bound/coupled with other compounds, and therefore difficult to detect. Such complexes in which the toxins are masked or hidden may even be at higher levels than the not-bound (free) molecules. The problem of how to evaluate effectively and efficiently the concentration of fumonisins in various foodstuffs is therefore a real-life challenge for scientists.

Following the earlier detection of six new esterified fumonisin B₁ (EFB₁) isomers containing three acyl groups in a Fusarium verticillioides-inoculated rice culture, it was assumed that linoleic, palmitic or oleic acid esterifies one of the free OH groups on the fumonisin backbone. On the basis of the results of our recent investigations we now propose that these EFB₁ isomers are actually 3-O- and 5-O-acyl derivatives of FB₁ (3-O-linoleoyl-FB₁, 5-O-linoleoyl-FB₁, 3-O-palmitoyl-FB₁, 5-O-palmitoyl-FB₁, 3-O-oleoyl-FB₁ and 5-O-oleoyl-FB₁). A F. verticillioides strain was identified that produced not only O-acyl-FB₁ isomers, but also low amounts of three N-acyl derivatives (N-linoleoyl-FB₁, N-palmitoyl-FB₁ and N-oleoyl-FB₁), which eluted from the HPLC column after the six O-acyl compounds and in the same sequence as for the O-acyl compounds. The characteristic positive and negative ESI-MS/MS spectra obtained after solid-phase extraction of the culture extract facilitated identification of these N-acyl-FB₁ derivatives. The biosynthesis of N-palmitoyl-FB₁ by F. verticillioides was verified by spiking the culture extract with synthetic N-palmitoyl-FB₁. This is the first report of the separation and mass spectrometric identification of the six O-acyl- and three N-acyl-FB₁ derivatives extracted from a F. verticillioides culture.

The presence of ochratoxin A (OTA), fumonisin B2 (FB2) and black aspergilli in raisins from Western Greece regions (Messinia, Corinthia, Achaia, Ilia and Zante Island) was investigated in relation to the different geographic and climatic conditions in the 2011 growing season. The biseriate species Aspergillus niger "aggregate" and A. carbonarius were mainly identified. The population of A. niger "aggregate" species occurred in all raisin samples at colony-forming units (CFU) concentrations significantly higher (mean 2.2 × 10(5) CFU g(-1) homogenate) than those of A. carbonarius population (mean 4.9 × 10(3) CFU g(-1) homogenate), which occurred in 80% of the raisin samples. OTA was found in 73% of the samples at levels ranging from 0.1 µg kg(-1) to 98.2 µg kg(-1), with the highest level occurring in a raisin sample from Ilia that also contained the highest level of A. carbonarius. The European Union legal limit for OTA was exceeded in 15% of the raisin samples. FB2 was found in 29% of the raisin samples at levels ranging from 7.1 µg kg(-1) to 25.5 µg kg(-1), with 20% of the samples co-occurring with OTA. Principal-component analysis was applied to levels of mycotoxins, fungal contamination, geographical data and environmental conditions recorded in the harvesting (August) or drying (September) period. Principal-component analysis clearly indicated a good direct correlation of rainfall and relative humidity with OTA and A. carbonarius contamination. A lack of clustering was observed when A. niger and FB2 contamination were considered. This is the first report on the co-occurrence of the mycotoxins OTA and FB2 in dried vine fruits from Greece.

Fumonisin derivatives obtained by esterification of fumonisin B₁ (FB₁) with palmitic, oleic and linoleic fatty acids have been recently described, but never reported in raw maize so far. In this study, the presence of oleoyl-EFB₁ (EFB₁OA) and linoleoyl-EFB₁ (EFB₁LA) in raw maize is reported by means of a suitable LC-ESI-MS/MS method. In addition, the production of EFB₁ derivatives by three Fusarium verticillioides strains is described on malt extract-based media and on corn meal-based growth media. EFB₁OA and EFB₁LA were produced by all considered strains in corn meal medium, with EFB₁LA > EFB₁OA. On the contrary, EFB₁OA and EFB₁LA were never observed in Fusarium cultures grown on a malt extract medium, suggesting that the esterification of FB₁ can occur only in a complex matrix such as maize.

Mycotoxins, together with endotoxins, represent important classes of naturally occurring contaminants in food products, posing significant health risks to consumers. The aim of this study is to investigate the occurrence of both Fusarium mycotoxins and endotoxins in commercially produced traditional banana beer. Two brands of commercially produced traditional banana beer were collected from a local retail market in Kigali, Rwanda. Beer samples were analysed for the presence of deoxynivalenol (DON), fumonisin B₁ and zearalenone (ZEA), using an enzyme-linked immuno-sorbent assay (ELISA) method. The quantification of bacterial endotoxin using Limulus amoeboecyte lysate (LAL) assay was also conducted. The contamination levels were 20 and 6.7 µg kg⁻¹ for DON; 34 and 31.3 µg kg⁻¹ for FB₁; 0.66 and 2.2 µg kg⁻¹ for ZEA in brands A and B of the beers, respectively. Results indicate that the levels of Fusarium toxins and bacterial endotoxin reported in this study did not pose adverse human health effects as a result of drinking/consuming banana beer. However, exposure to low/sub-threshold doses or non-toxic levels of endotoxins magnifies the toxic effect of xenobiotic agents (e.g. fungal toxins) on liver and other target organs. Considering Fusarium toxins and/or endotoxin contamination levels in other agricultural commodities intended for human consumption, health risks might be high and the condition is aggravated when beer is contaminated by mixtures of the mycotoxins, as indicated in this study.

Fumonisin B₁ (FB₁) and B₂ (FB₂) are mycotoxins produced by Fusarium verticillioides and F. proliferatum and common contaminants of cereal crops. The objectives of this study were to (1) study the occurrence of fumonisins in Catalonia (north-eastern region of Spain) and (2) assess the exposure of the Catalonian population to these mycotoxins. Contamination data was provided by a wide survey where 928 individual samples were pooled to analyse 370 composite samples. Fumonisins were extracted and purified using immunoaffinity columns and determined by HPLC with fluorescence detection. The raw consumption data came from a nutritional study specifically designed to assess the dietary intake of the main foodstuffs related to fumonisin contamination for all population age groups. In addition, two specific groups were selected with respect to maize consumption: immigrants and celiac sufferers. Contamination and consumption data were combined by simulation using an essentially parametric-parametric (P-P) method. The P-P method draws sampling values from distribution functions fitted to consumption and contamination datasets. Moreover, to quantify the accuracy and reliability of the statistical estimates, we built related confidence intervals using a Pseudo-Parametric bootstrap method. The results of this study show that fumonisins are commonly found in some commodities on the Catalonian market, such as beer, corn snacks and ethnic foods; however, the values were well below the permitted maximum EU levels. The most exposed group were infants followed by immigrants but, in all cases, they were below the TDI of 2 µg/kg bw/day.

The ability of the fungus Fusarium proliferatum to cause kernel black point disease in wheat was previously established, but natural contamination of black point wheat with both F. proliferatum and fumonisin mycotoxins has not been studied in the United States. Low levels of fumonisins were detected in nine of 43 wheat samples with kernel black point disease that were obtained from across the United States. A subset of samples was contaminated with F. proliferatum as well as with F. fujikuroi, F. nygamai, F. thapsinum and F. verticillioides, species closely related to F. proliferatum and morphologically similar to it in that they produce chains of asexual spores, or conidia. Nevertheless, of conidial chain-forming fusaria isolated from symptomatic wheat, F. proliferatum dominated. In greenhouse tests, isolates of F. proliferatum and the other species recovered from wheat samples were able to cause symptoms of kernel black point and, in some cases, low levels of fumonisin contamination of wheat. These data add to the understanding of the risk of fumonisin contamination of wheat and the potential for Fusarium species to cause kernel black point disease and fumonisin contamination of wheat. Further, the results of this study indicate that while US-grown wheat can sporadically be contaminated by fumonisins, the natural contamination levels seem to be low. The observations made provide evidence that fumonisins are not likely to be a factor contributing to the ability of Fusarium to cause kernel black point disease.

An LC-MS/MS method was developed and validated for the simultaneous determination of deoxynivalenol, zearalenone, T-2-toxin, HT-2-toxin and metabolites, including 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, deoxynivalenol-3-glucoside, α-zearalenol, β-zearalenol, zearalenone-4-glucoside, α-zearalenol-4-glucoside, β-zearalenol-4-glucoside and zearalenone-4-sulfate in maize, wheat, oats, cornflakes and bread. Extraction was performed with acetonitrile/water/acetic acid (79/20/1, v/v/v) followed by a hexane defatting step. After filtration, the extract was evaporated and the residue was redissolved in mobile phase for injection. The mobile phase, which consisted of a mixture of methanol and water with 10 mM ammonium acetate, was adjusted to pH 3 with glacial acetic acid. A sample clean-up procedure was not included because of the low recoveries of free and masked mycotoxins and their differences in polarity. The method allowed the simultaneous determination of 13 Fusarium mycotoxins in a one-step chromatographic run using a Waters Acquity UPLC system coupled to a Quattro Premier XE mass spectrometer. The method was validated for several parameters such as linearity, apparent recovery, limit of detection, limit of quantification, precision, expanded measurement uncertainty and specificity. The limits of detection varied from 5 to 13 ng g⁻¹; those for the limit of quantification from 10 to 26 ng g⁻¹. The results of the performance characteristics of the developed LC-MS/MS method were in good agreement with the criteria mentioned in Commission Regulation (EC) No. 401/2006. Thirty samples of a variety of food and feed matrices were sampled and analysed between July 2010 and January 2011.

Fumonisin B₁ (FB₁) is often a co-contaminant with aflatoxin (AF) in grains and may enhance AF's carcinogenicity by acting as a cancer promoter. Calcium montmorillonite (i.e. NovaSil, NS) is a possible dietary intervention to help decrease chronic aflatoxin exposure where populations are at risk. Previous studies show that an oral dose of NS clay was able to reduce AF exposure in a Ghanaian population. In vitro analyses from our laboratory indicated that FB₁ (like aflatoxin) could also be sorbed onto the surfaces of NS. Hence, our objectives were to evaluate the efficacy of NS clay to reduce urinary FB₁ in a rodent model and then in a human population highly exposed to AF. In the rodent model, male Fisher rats were randomly assigned to either FB₁ control, FB₁ + 2% NS or absolute control group. FB₁ alone or with clay was given as a single dose by gavage. For the human trial, participants received NS (1.5 or 3 g day⁻¹) or placebo (1.5 g day⁻¹) for 3 months. Urines from weeks 8 and 10 were collected from the study participants for analysis. In rats, NS significantly reduced urinary FB₁ biomarker by 20% in 24 h and 50% after 48 h compared to controls. In the humans, 56% of the urine samples analysed (n = 186) had detectable levels of FB₁. Median urinary FB₁ levels were significantly (p < 0.05) decreased by >90% in the high dose NS group (3 g day⁻¹) compared to the placebo. This work indicates that our study participants in Ghana were exposed to FB₁ (in addition to AFs) from the diet. Moreover, earlier studies have shown conclusively that NS reduces the bioavailability of AF and the findings from this study suggest that NS clay also reduces the bioavailability FB₁. This is important since AF is a proven dietary risk factor for hepatocellular carcinoma (HCC) in humans and FB₁ is suspected to be a dietary risk factor for HCC and oesophageal cancer in humans.

Fusarium species (spp.) and fumonisin B₁ (FB₁) contaminations were monitored in maize and porridge consumed by a rural population of Limpopo Province, South Africa. Faecal samples were also analysed for FB₁ as a means of estimating the degree of dietary exposure to this mycotoxin. In total, 142 samples of maize (n = 54), porridge (47) and faeces (41) were screened for Fusarium spp. using a serial dilution technique followed by DNA sequencing, while FB₁ was further screened and quantified by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), respectively. At least four species of Fusarium were identified, of which F. verticillioides was the most prevalent in all three sample types analysed. The contamination levels of FB₁ were significantly higher in 87% of maize sampled (range = 101-53,863 µg kg⁻¹) as compared with porridge (74% incidence rate; range = 0.2-20 µg kg⁻¹) and faecal samples (100% incidence rate; range = 0.3-464 µg kg⁻¹). Thus, it can be deduced that the level of human exposure to FB₁ via the consumption of maize was high as several samples contained levels exceeding 1000 µg kg⁻¹, which was strongly supported by the levels found in faecal samples. Further data revealed that a high proportion of FB₁ is destroyed or removed by processing maize into porridge. As maize porridge is consumed as a staple, the low levels found provide a means to limit exposure to FB₁. Levels of FB₁ found in the faeces which were higher indicate that other foods contaminated with the toxin are also consumed.

Fumonisins are a group of structurally related mycotoxins produced mainly in maize by Fusarium verticillioides and F. proliferatum. The most abundant naturally occurring analogue is fumonisin B(1) (FB(1)), with lesser amounts of fumonisin B(2) (FB(2)) and fumonisin B(3) (FB(3)) occurring. The C-series fumonisins (FCs) are structurally analogous to the B-series but lack the C-1 methyl group. Good and mouldy subsistence-grown maize samples were collected from the Centane and Bizana districts in the former Transkei region of South Africa. After extraction with methanol/water and clean-up on strong anion exchange solid phase extraction cartridges, FB(1), FB(2), FB(3), FC(1), FC(3) and FC(4) were determined by reversed-phase LC-MS/MS using positive ion electrospray ionisation. FB(1) levels in both good and mouldy maize from Centane (means (±SD) 2.75 ± 2.24 and 23.4 ± 12.5 mg kg(-1), respectively) were higher than the corresponding levels in maize samples from Bizana (means 0.056 ± 0.157 and 3.71 ± 5.01 mg kg(-1), respectively). Similarly, FC(1) levels in both good and mouldy maize from Centane (means 0.107 ± 0.099 and 0.814 ± 0.391 mg kg(-1), respectively) were higher than in Bizana, where FC(1) was detected in only one (0.018 mg kg(-1)) of 19 good maize samples and occurred in mouldy maize with a mean of 0.102 ± 0.135 mg kg(-1). A significant correlation (r=0.982, p<0.01) was observed between FB(1) and FC(1) levels in all samples, with FC(1) levels at 3.3% of the corresponding FB(1) levels. FC(4) levels were similar to FC(1), whereas only low amounts of FC(3) were detected., (© 2011 Taylor & Francis)

Fumonisins are important Fusarium mycotoxins mainly found in maize and derived products. This study analysed maize from five subsistence farmers in the former Transkei region of South Africa. Farmers had sorted kernels into good and mouldy quality. A total of 400 kernels from 10 batches were analysed; of these 100 were visually characterised as uninfected and 300 as infected. Of the 400 kernels, 15% were contaminated with 1.84-1428 mg kg(-1) fumonisins, and 4% (n=15) had a fumonisin content above 100 mg kg(-1). None of the visually uninfected maize had detectable amounts of fumonisins. The total fumonisin concentration was 0.28-1.1 mg kg(-1) for good-quality batches and 0.03-6.2 mg kg(-1) for mouldy-quality batches. The high fumonisin content in the batches was apparently caused by a small number (4%) of highly contaminated kernels, and removal of these reduced the average fumonisin content by 71%. Of the 400 kernels, 80 were screened for 186 microbial metabolites by liquid chromatography-tandem mass spectrometry, detecting 17 other fungal metabolites, including fusaric acid, equisetin, fusaproliferin, beauvericin, cyclosporins, agroclavine, chanoclavine, rugulosin and emodin. Fusaric acid in samples without fumonisins indicated the possibility of using non-toxinogenic Fusaria as biocontrol agents to reduce fumonisin exposure, as done for Aspergillus flavus. This is the first report of mycotoxin profiling in single naturally infected maize kernels., (© 2011 Taylor & Francis)

Fusarium is the agent causing endosepsis (internal rot) in fig fruits and it is widespread in fig orchards in the Aegean region. This research was conducted to determine the natural occurrence of fumonisin B(1) (FB(1)) and B(2) (FB(2)) on dried fig fruits of Sarilop (syn. Calimyrna) variety which are mainly grown in the Big and Small Meander Basins in the Aegean region, representing 60% of world dried fig production. A total of 262 samples belonging to two quality classes, Class A and Class cull, were collected from 12 different locations during the two crop years in 2004 and 2005. The fumonisin detection method is based on extraction with methanol-acetonitrile-water, derivatization with o-phthaldehyde and quantification by reversed-phase high-performance liquid chromatography with fluorescence detection. The mean concentrations of FB(1) and FB(2) in fumonisin-positive samples were 0.080 ± 0.047 µg g(-1) and 0.055 ± 0.031 µg g(-1) and ranged from LOD to 0.332 µg g(-1) and from LOD to 0.198 µg g(-1), respectively. The incidence of fumonisins significantly differed between the two crop years. This difference can be attributed to the alteration in the rainfall regime from mid-May to mid-August (7.2 mm in 2004, 90.9 mm in 2005) and number of humid wind currents from a westerly direction (183 in 2004, 492 in 2005) from the end of July and mid-August that may have triggered a higher incidence of Fusarium spp. and thus fumonisin production.

Approximately 200 samples of rice (including white, brown, red, black, basmati and jasmine, as well as wild rice) from several different countries, including the United States, Canada, Pakistan, India and Thailand, were analysed for aflatoxins, ochratoxin A (OTA) and fumonisins by separate liquid chromatographic methods in two different years. The mean concentrations for aflatoxin B(1) (AFB(1)) were 0.19 and 0.17 ng g(-1) with respective positive incidences of 56% and 43% (≥ the limit of detection (LOD) of 0.002 ng g(-1)). Twenty-three samples analysed in the second year also contained aflatoxin B(2) (AFB(2)) at levels ≥LOD of 0.002 ng g(-1). The five most contaminated samples in each year contained 1.44-7.14 ng AFB(1) g(-1) (year 1) and 1.45-3.48 ng AFB(1) g(-1) (year 2); they were mostly basmati rice from India and Pakistan and black and red rice from Thailand. The average concentrations of ochratoxin A (OTA) were 0.05 and 0.005 ng g(-1) in year 1 and year 2, respectively; incidences of samples containing ≥LOD of 0.05 ng g(-1) were 43% and 1%, respectively, in the 2 years. All positive OTA results were confirmed by LC-MS/MS. For fumonisins, concentrations of fumonisin B(1) (FB(1)) averaged 4.5 ng g(-1) in 15 positive samples (≥0.7 ng g(-1)) from year 1 (n = 99); fumonisin B(2) (FB(2)) and fumonisin B(3) (FB(3)) were also present (≥1 ng g(-1)). In the second year there was only one positive sample (14 ng g(-1) FB(1)) out of 100 analysed. All positive FB(1) results were confirmed by LC-MS/MS.

A comparison study of different extraction and clean-up procedures for the liquid chromatographic analysis of fumonisins B(1) (FB(1)) and B(2) (FB(2)) in corn masa flour was performed. The procedures included extraction (heat or room temperature) with acidic conditions or EDTA-containing solvents, and clean-up by immunoaffinity or C18 solid-phase extraction columns. Thereafter an analytical method was optimised using extraction with an acidic mixture of methanol-acetonitrile-citrate/phosphate buffer, clean-up through the immunoaffinity column and determination of fumonisins by liquid chromatography with automated pre-column derivatisation with o-phthaldialdehyde reagent. Recovery experiments performed on yellow, white and blue masa flours at spiking levels of 400, 800 and 1200 µg kg(-1) FB(1) and of 100, 200 and 300 µg kg(-1) FB(2) gave overall mean recoveries of 99% (±6%) for FB(1) and 88% (±6%) for FB(2). Good recoveries (higher than 90% for both FB(1) and FB(2)) were also obtained with corn tortilla chips. The limits of quantification of the method (signal-to-noise ratio of 10) were 25 µg kg(-1) for FB(1) and 17 µg kg(-1) for FB(2). The method was tested on different commercial corn masa flours as well as on white and yellow corn tortilla chips, showing fumonisin contamination levels (FB(1) + FB(2)) up to 1800 µg kg(-1) (FB(1) + FB(2)) in masa flour and 960 µg kg(-1) in tortilla chips. Over 30% of masa flours originating from Mexico exceeded the European Union maximum permitted level.

Aflatoxins and fumonisins are ubiquitous foodborne toxicants and the co-occurrence of these mycotoxins in human foods represents a significant public health concern, which has been strongly associated with human aflatoxicosis, neural tube defects, as well as many types of primary cancers. In this study the co-contamination of aflatoxin B(1) (AFB(1)) and fumonisin B(1) (FB(1)) in food and human dietary exposure was investigated in residents of three different areas of China. A total of 209 food samples were measured for AFB(1) and FB(1). The median AFB(1) levels were 13.5, 2.3 and 1.3 µg kg(-1) and the median FB(1) levels were 2.6, 0.4 and 0.3 mg kg(-1) in corn samples collected from Huaian (a high-risk area for oesophageal cancer), Fusui (a high-risk area for liver cancer) and Huantai (a low-risk area for both oesophageal and liver cancers), respectively. The median level of AFB(1) in plant oil of Fusui was the highest (52.3 µg kg(-1)) among all food samples analysed. Co-contamination of these two mycotoxins was found in corn, rice and wheat flour. Based on measured food consumption data, the averaged daily dietary intake of AFB(1) was 0.397 µg (range = 0.269-1.218 µg) in residents of Huantai, 1.723 µg (0.224-49.772 µg) in Huaian, and 2.685 µg (1.006-14.534 µg) in Fusui. The averaged FB(1) daily dietary intake was 92.4 µg (range = 55.0-362.1 µg) for residents of Huantai, 460.0 µg (83.2-2894.5 µg) in Huaian, and 138.6 µg (30.0-10,541.6 µg) in Fusui. These data suggest that the co-exposure to AFB(1) and FB(1) in residents of rural China may contribute to the aetiology of human chronic diseases in high-risk areas.

In the Centane magisterial area of South Africa, high rates of oesophageal cancer have been associated with home-grown maize contaminated with fumonisins. The aim of this study was to implement a simple intervention method to reduce fumonisin exposure in a subsistence-farming community. The hand-sorting and washing procedures, based on traditional maize-based food preparation practices, were previously customised under laboratory-controlled conditions. Home-grown maize and maize-based porridge collected at baseline were analysed for fumonisin B(1), B(2) and B(3). The geometric mean (95% confidence interval) of fumonisin contamination in the home-grown maize at baseline was 1.67 (1.21-2.32) mg kg(-1) and 1.24 (0.75-2.04) mg kg(-1) (dry weight) in the porridge. Fumonisin exposure was based on individual stiff porridge consumption and the specific fumonisin levels in the porridge (dry weight) consumed. Porridge (dry weight) consumption at baseline was 0.34 kg day(-1) and fumonisin exposure was 6.73 (3.90-11.6) µg kg(-1) body weight day(-1). Female participants (n = 22) were trained to recognise and remove visibly infected/damaged kernels and to wash the remaining maize kernels. The discarded kernels represented 3.9% by weight and the fumonisins varied from 17.1 to 76.9 mg kg(-1). The customised hand-sorting and washing procedures reduced fumonisin contamination in the maize and porridge by 84 and 65%, respectively. The intervention reduced fumonisin exposure by 62% to 2.55 (1.94-3.35) µg kg(-1) body weight day(-1). This simple intervention method has the potential to improve food safety and health in subsistence-farming communities consuming fumonisin-contaminated maize as their staple diet.

The aim of this research was to determine the fate of aflatoxins (AFs) and fumonisins (FBs) naturally occurring in raw materials (maize grit and malted barley) during four industrial brewing processes. The aflatoxin B(1) (AFB(1)) level in raw materials varied from 0.31 to 14.85 microg kg(-1), while the fumonisin B(1) (FB(1)) level (only in maize grit) varied from 1146 to 3194 microg kg(-1). The concentration in finished beer ranged from 0.0015 to 0.022 microg l(-1) for AFB(1) and from 37 to 89 microg l(-1) for FB(1); the other aflatoxins and fumonisin B(2) were not found in beer samples. The average percentage of toxins recovered in finished beer, referring to the amounts contained in raw materials, were 1.5% +/- 0.8% for AFB(1) and 50.7% +/- 4.7% for FB(1). These results were mainly due to the different solubility of the two mycotoxins during the mashing process. If raw materials comply with the limits fixed by European Commission Regulations, the contribution of a moderate daily consumption of beer to AFB(1) and FB(1) intake does not contribute significantly to the exposure of the consumer.

Levels of serum and urinary sphinganine (Sa) and sphingosine (So), the Sa/So ratio, and urinary-free fumonisin B(1) (FB(1)) were determined in a cross-sectional study consisting of 43 adults in Huaian and 34 adults in Fusui, China. Home-produced corn had 100% contamination with FB(1). There were 93.0% (40/43) of Huaian subjects and 52.9% (18/34) of Fusui subjects with daily FB(1) intakes greater than 2 microg kg(-1) body weight, which showed a significant difference (p < 0.01). Levels of sphinganine and sphingosine and the Sa/So ratio were not correlated with levels of dietary exposure. The median level of the serum Sa/So ratio in Huaian subjects (0.41, range = 0.14-0.85) was significantly lower than that in Fusui subjects (0.78, range = 0.57-1.08) (p < 0.01). The median level of the urinary Sa/So ratio was also significantly lower in Huaian subjects (0.31, range = 0.08-1.33) than in Fusui subjects (0.57, range = 0.03-2.52) (p < 0.01). Urinary-free FB(1) was detected in 83.7% (36/43) of Huaian samples and in 82.4% (28/34) of Fusui urine samples (p > 0.05). However, the median level of urinary-free FB(1) in Huaian subjects, 3.91 (range = 0.06-253.61) ng mg(-1) creatinine, was significantly higher than 0.39 (range = 0.01-3.72) ng mg(-1) creatinine found in Fusui subjects (p < 0.01). These results suggest that urinary-free FB(1) may be a potential biomarker for human fumonisin exposure, while further validation is needed in human epidemiological and intervention studies.

The potential risk of exposure to fumonisin B(2) (FB(2)) in the grape-wine chain has recently been revealed after a report of Aspergillus niger in grapes and its ability to produce FB(2) and FB(4). The occurrence of these two fumonisins in wine was investigated by LC/MS/MS in 51 market samples (45 red, five white and one rose wine) produced in various Italian regions. Nine samples of red wine were found to be contaminated by fumonisin B(2) at levels ranging from 0.4 to 2.4 ng/ml, while FB(4) was not detected in any of the tested samples. This is the first report on the natural occurrence of FB(2) in wine, indicating that, although at low levels, there is a potential risk of FB(2) exposure for the wine-consumer.

Fusarium ear rot, caused by Fusarium verticillioides, is one of the most common diseases of maize, causing yield and quality reductions and contamination of grain by fumonisins and other mycotoxins. Drought stress and various insects have been implicated as factors affecting disease severity. Field studies were conducted to evaluate the interactions and relative influences of drought stress, insect infestation, and planting date upon Fusarium ear rot severity and fumonisin B1 contamination. Three hybrids varying in partial resistance to Fusarium ear rot were sown on three planting dates and subjected to four irrigation regimes to induce differing levels of drought stress. A foliar-spray insecticide treatment was imposed to induce differing levels of insect injury. Populations of thrips (Frankliniella spp.), damage by corn earworm (Helicoverpa zeae), Fusarium ear rot symptoms, and fumonisin B1 levels were assessed. There were significant effects of hybrid, planting date, insecticide treatment, and drought stress on Fusarium ear rot symptoms and fumonisin B1 contamination, and these factors also had significant interacting effects. The most influential factors were hybrid and insecticide treatment, but their effects were influenced by planting date and drought stress. The more resistant hybrids and the insecticide-treated plots consistently had lower Fusarium ear rot severity and fumonisin B1 contamination. Later planting dates typically had higher thrips populations, more Fusarium ear rot, and higher levels of fumonisin B1. Insect activity was significantly correlated with disease severity and fumonisin contamination, and the correlations were strongest for thrips. The results of this study confirm the influence of thrips on Fusarium ear rot severity in California, USA, and also establish a strong association between thrips and fumonisin B1 levels.

The European corn borer (ECB), Ostrinia nubilalis, is the principal pest of maize in Central and South Europe. It is known to promote Fusarium verticillioides infection in maize grain, a recognized producer of fumonisins. Field experiments were performed in 2006 and 2007 in two sites in NW Italy to determine the effects of the timing of insecticide application on ECB damage, fungal ear rot and fumonisin contamination under natural conditions. Different insecticide application timings were compared, from maize flowering to approximately 15 days after the flight peak of adult ECB. At harvest, the ears were rated for incidence and severity of ECB damage, fungal ear rot symptoms and fumonisin (FB(1) + FB(2)) contamination. In all years/sites, treatments applied at the beginning of consistent ECB flight activity were most effective in controlling insect damage on ears. Fungal ear rot and fumonisin contamination were significantly affected by ECB control. The efficacy of the best timing of insecticide application in controlling fumonisin contamination was, on average, 93% compared to the untreated control. Contamination levels of these mycotoxins increased with either an earlier or later treatment. Furthermore, an earlier insecticide application showed lower fumonisin contamination than a treatment applied after the adult flight peak. Production of maize kernels and maize-based foods that do not exceed the maximum international and EU permitted levels for fumonisins could be enhanced by appropriate insecticide treatment against second generation ECB. The optimum time for insecticide application is between the beginning of consistent adult flight activity and the flight peak.

A molecularly imprinted polymer (MIP) for the recognition of fumonisin B analogues (FB) using 2-(diethylamino) ethyl methacrylate (DEAEM) as functional monomer and trimethylolpropane trimethacrylate (TRIM) as cross-linker was prepared by bulk polymerization in acetonitrile. Fumonisin B(1) (FB(1)) was used as a template molecule. A molecularly imprinted solid-phase extraction (MISPE) procedure was developed for further application in the analysis of FB. The performance of the MIP throughout the clean-up of spiked bell pepper, rice and corn flake sample extracts was compared with the results obtained when using non-imprinted polymer, C(18), strong anion exchange and immunoaffinity sorbents. Extracts were analysed for FB with liquid chromatography-tandem mass spectrometry (LC-MS/MS) after clean-up. Depending on the food matrix and the concentration range of the fumonisins, recoveries after MISPE varied from 62 to 86%, from 62 to 83%, and from 67 to 81% for fumonisin B(1) (FB(1)), fumonisin B(2) (FB(2)) and fumonisin B(3) (FB(3)), respectively. The selectivity of the synthesized MIP for mycotoxins belonging to the group of FB was confirmed by evaluating cross-reactivity from analogue structures and other mycotoxins. Analysis of 39 naturally contaminated samples (corn flakes) by liquid chromatography tandem mass spectrometry indicated that the synthesized MIP could be an excellent alternative for clean-up and pre-concentration of FB in food samples. Pearson correlations between immunoaffinity clean-up and MISPE were calculated and amounted to 0.923 for FB(1), 0.808 for FB(2), and 0.759 for FB(3). It was shown that the developed MIP could be reused more than 50 times. The synthesis of an FB(1) imprinted polymer and its application in food analysis is reported for the first time.

The objective was to determine the effect of added sodium chloride, barley malt and sucrose on the stability of fumonisin B1 (FB1) present in corn flour. Two levels of both sodium chloride (0.4% and 2%) and barley malt (0.8% and 5%) were added to the unextruded corn flour, and six levels of sucrose (3-10%) were used. The addition of sucrose at the lowest salt content (0.4%) as well as salt, either at 0.4% or at 2%, led to a significant decrease of FB1 levels in extruded samples, whereas malt, either at 0.8% or at 5%, did not significantly affect FB1 stability. Decontamination rates depended on the concentrations of added ingredients and ranged from 2% to 92%. The greatest reductions in FB1 content were achieved with extrusion cooking with a high salt content, whilst the lowest reductions were the result of processing corn flour with low contents of both salt and sucrose. Salt at 2% was the most effective ingredient in reducing FB1 content of the final extruded food.

The aim was to evaluate the distribution of aflatoxins and fumonisins in fractions derived from the dry-milling of contaminated maize. Two maize lots with different contamination levels were processed and sampled: the first (maize 1) had aflatoxin B(1) (AFB(1)) and fumonisin B(1) (FB(1)) levels of 3.6 and 5379 microg kg(-1), respectively; the second (maize 2) had corresponding levels of 91.1 and 8841 microg kg(-1), respectively. The cleaning step reduced AFB(1) and FB(1) levels by 8 and 11% in maize 1 and by 57 and 34% in maize 2. The subsequent removal of bran and germ led to a further decrease in contamination levels in the products destined for human consumption. In the latter, AFB(1) was uniformly distributed, while FB(1) was concentrated in the finer size fractions. Contamination of raw maize 1 (3.6 microg kg(-1)) was below the European Union AFB(1) limit of 5 microg kg(-1) for unprocessed maize, but among the final products only coarse flour (1.7 microg kg(-1)) was within the European Union limit of 2 microg kg(-1), while grits and fine flour showed higher levels (2.7 and 2.5 microg kg(-1), respectively). As regards cleaned maize, a different distribution of the two toxins was observed in the kernels: AFB(1) contamination was more superficial and concentrated in germ, while FB(1) contamination affected the inner layers of the kernels.

This study examined a total of 82 consignments of French and Argentinean raw maize as received at maize mills in the UK between 2004 and 2007. Samples were analysed for deoxynivalenol (DON), nivalenol (NIV), other trichothecenes, zearalenone (ZON), and fumonisins B(1), B(2), and B(3) (FB(1), FB(2), and FB(3)) using fully validated analytical methods with limits of quantification of 10 microg kg(-1) for DON, NIV, and each fumonisin mycotoxin and 3 microg kg(-1) for ZON. All samples except two containing fumonisins met the European Commission statutory maximum permissible levels for DON, ZON, and FB(1) + FB(2) as operating in 2007. The maximum concentrations found for DON, NIV, ZON, and FB(1) + FB(2) were 444, 496, 165 and 5002 microg kg(-1), respectively. Fumonisins were detected in almost every sample with 65% of Argentinean maize containing more than 1000 microg kg(-1) of FB(1) + FB(2). In contrast, ZON was not detectable in almost 50% of consignments. During this period there was a distinct difference in mycotoxin concentrations between harvests and geographic origin. Flint maize from Argentina usually contained lower concentrations of DON and related trichothecenes and higher levels of fumonisins than maize from France, although concentrations of fumonisins up to 2000 microg kg(-1) or greater occurred in samples from both regions. The incidence and concentrations of fumonisins were similar to those in a similar previous survey, while zearalenone concentrations were lower. The distribution of mycotoxins in multi-hold ships was also investigated showing that fumonisins were much more evenly distributed than DON, thus indicating their general level in the ship as a whole. The effect of cleaning regimes was found to be very variable, especially for DON, ranging from no removal of mycotoxins to greater than 50% in some instances, but was not related to concentration. Evidence here suggests that while cleaning is essential for removing foreign bodies before milling, it cannot be used as a reliable tool for reducing mycotoxins.

High incidences of oesophageal cancer are associated with the consumption of subsistence-grown maize by rural populations in the former Transkei region of Eastern Cape Province, South Africa. This cross-sectional study was conducted in the north-eastern magisterial area of Bizana (a previously low oesophageal cancer incidence area) and the south-eastern area of Centane (a previously high incidence area). Plasma and urine samples of male and female participants were analysed for the sphingoid bases, sphinganine and sphingosine. Good home-grown and visibly mouldy maize samples, collected from the households of the participants, were analysed for fumonisin B(1), B(2) and B(3). Plasma sphinganine/sphingosine ratios in males and females were significantly lower (p < 0.05) due to lower sphinganine levels in Bizana compared to Centane. In contrast, the urinary female and combined (males + females) sphinganine/sphingosine ratios were significantly higher (p < 0.05) in Bizana due to the significantly lower (p < 0.05) urinary sphingosine levels. Interestingly, urinary sphingoid base levels were significantly lower (p < 0.05) in males than females within each area. Based on the mean total fumonisin levels in good maize, the estimated mean probable daily intake (PDI) was 5.8 microg kg(-1) body weight day(-1) in Bizana during 2000 and 4.4 and 6.7 5.8 microg kg(-1) body weight day(-1) in Centane during 1997 and 2000, respectively, exceeding the maximum tolerable daily intake proposed by JECFA. However, there was no significant difference in the mean total fumonisin levels in the maize between the magisterial areas. The observed differences in plasma and urinary sphingoid base levels could not be ascribed as a biomarker of fumonisin exposure and further studies at an individual level are required.

Based on fungal and fumonisin contamination of 870 freshly harvested samples, the quality of corn used by processing industries in the Northern region of Parana State, Brazil (2003 and 2004 crop-year) was evaluated. Sampling was carried out for each crop at two points in the production chain, i.e. at reception by the processors and at the pre-drying step. Corn samples were more frequently contaminated with Fusarium sp. (100%) and Penicillium sp. (84.1-95.3%) than Aspergillus sp. (5.6-19.8%). Fumonisin B(1) (FB(1)) was detected in all samples from the two points in both crop-years. FB(1) levels ranged 0.02-11.83 microg g(-1) in the reception and 0.02-10.98 microg g(-1) in the pre-drying samples of the 2003 crop. Samples from the 2004 crop showed FB(1) levels ranging 0.03-12.04 microg g(-1) in the reception and 0.06-7.74 microg g(-1) in the pre-drying samples. FB(2) levels ranged 0.02-5.25 microg g(-1) in the reception and 0.01-7.89 microg g(-1) in the pre-drying samples (2003 crop-year). In samples from the 2004 crop, FB(2) levels ranged 0.02-6.12 microg g(-1) in the reception and 0.05-3.47 microg g(-1) in the pre-drying samples. Low fumonisin levels were detected in most corn samples used by processors in the Northern region of Parana State, showing a decreasing trend in fumonisin contamination over the years.