Fumonisin Research Articles

MYCOTOXIN CONTAMINATION ON CORN USED BY FEED MILLS IN INDONESIA

Mycotoxins which are secondary metabolites of fungi contaminate agricultural products such as corn and have deleterious effects on human and animal. The objective of this study was to evaluate the mycotoxin contamination on local and imported corn samples collected from different feed mills in Indonesia. Three hundred fifty six of corn samples (0.50 kg each) were sent by several feed mills to the Indonesian Research Institute for Animal Production during 2005-2006. The background information accompanied with each sample was country/province of origins, harvesting seasons, postharvest drying methods, moisture levels, grades, and varieties. The samples were analyzed for various mycotoxins, i.e aflatoxin (AFL), ochratoxin (OCRA), zearalenone (ZEN), fumonisin (FUM), deoxynivalenol (DON), and T2 toxin using commercial kits, except for AFL which was analysed using a kit developed by the Indonesian Research Center for Veterinary Science. The results showed that average AFL level in the contaminated corn originated from Indonesia was 59 µg kg-1, almost 7 times higher than that imported from the USA or Argentina. Among the types of mycotoxins detected, FUM was the highest with an average of 1193 µg kg-1, followed by DON, ZEN and OCRA at level of 324, 22 and 2 µg kg-1, respectively. Mycotoxin levels in the contaminated local corn samples varied depending on the province of origins as well as harvesting seasons, postharvest drying methods, and moisture contents. The least mycotoxin contaminations were found on corn originated from North<br />Sumatra and Lampung with the AFL levels were < 20 and < 50 µg kg-1, respectively, lower than those from East Java, Central Java and South Sulawesi (64-87 µg kg-1). Mycotoxin levels, however, were less affected by grading made by feed mills and corn varieties. It is indicated that AFL was the most important mycotoxin as far as for animal feeding concerned, as it contaminated almost 50% of local corn with the level of contamination above the Indonesian National Standard, i.e. 50 µg kg-1. The study suggests that postharvest methods of local corn must be improved to reduce mycotoxin contamination.

0115 Occurrence of mycotoxins in the 2015 U.S. corn crop

Mycotoxins are toxic metabolites produced by filamentous fungi which commonly contaminate feedstuffs harvested for both human and livestock consumption. Although the different types of mycotoxins have variable effects on different livestock species, exposure to mycotoxins can impair health and adversely affect animal performance. The objective of the current study was to determine the occurrence of mycotoxins in the 2015 corn crop in the United States and to assess the potential risk to livestock species. From September 2015 to January 2016, 381 corn samples were collected from 20 states as part of the annual Biomin Mycotoxin Survey. Samples were analyzed either by high performance liquid chromatography (HPLC) or liquid chromatography tandem mass spectrometry (LC-MS/MS) techniques, which are highly sensitive in detecting very low mycotoxin concentrations. The major mycotoxin groups analyzed were aflatoxins (Afla), zearalenone (ZEN), trichothecenes including deoxynivalenol (DON) and T-2 toxin (T-2), fumonisins (FUM), and ochratoxin A (OTA). Mycotoxins were detected in 94% of the corn samples tested and 50% of the positive samples contained more than one mycotoxin. Co-occurrence of mycotoxins may lead to synergism and enhanced toxicity in animals which consume contaminated feed. The percentage of positive samples, mean of positives (ppb), maximum of positives (ppb), and risk threshold (ppb) for the six major mycotoxins are presented in Table 1 (not available). The occurrence of Afla, T-2, and OTA were minimal in relation to ZEN, DON, and FUM in these samples. The highest threat in these corn samples was posed by DON due to its high prevalence and number of samples above the FDA recommended level. As a result of their common co-occurrence, ZEN also presents a major threat. In terms of occurrence, FUM ranks second among the six major mycotoxins analyzed in these samples. With the increased occurrence and co-occurrence levels in 2015 compared with the previous year, DON, FUM, and ZEN pose a higher risk to livestock production in 2016.

Chemical, physical and technological properties of milk as affected by the mycotoxin load of dairy herds

Abstract. The aim of the study was to determine the impacts of different levels of mycotoxin load of Czech dairy herds on the larger scale of the milk indicators including milk physical and technological properties. During three subsequent years individual milk samples (IMSs) were collected from four herds of Czech Fleckvieh (C) and from four herds of Holstein cows (H). The IMSs were collected regularly twice in summer and twice in winter, resulting in a total of 936 IMSs. The feeding rations consisted mainly of conserved roughage and supplemental mixtures according to milk yield and standard demands. Samples of feedstuffs were collected at the same time as IMSs and were analysed for content of deoxynivalenol (DON), fumonisins (FUM), zearalenone (ZEA), aflatoxin (AFL), and T-2 toxin using enzyme-linked immunosorbent assay (ELISA) methods. Based on the mycotoxin load, herds were divided into three groups – Load 1 (negligible, n = 36), Load 2 (low, n = 192), and Load 3 (medium, n = 708). All feedstuff samples were positive for at least one mycotoxin. The most frequently occurring mycotoxins were FUM, DON, and ZEA. Relatively high incidence of AFL (56 % positive samples) was observed. The following milk indicators were influenced by the mycotoxin load of herds: fat, acetone (Ac), log Ac, pH, electric conductivity, alcohol stability, curds quality, curd firmness, whey volume, whey protein, non-protein nitrogen (NPN), urea N in NPN, fat ∕ crude protein ratio, and casein numbers on crude and true protein basis, respectively (P < 0.05). The overall level of mycotoxin load was relatively low, with no clear effect on milk characteristics.

Dietary exposure to mycotoxins of the Hong Kong adult population from a Total Diet Study

ABSTRACTDietary 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.

Natural Co-Occurrence of Mycotoxins in Foods and Feeds and Their in vitro Combined Toxicological Effects.

Some foods and feeds are often contaminated by numerous mycotoxins, but most studies have focused on the occurrence and toxicology of a single mycotoxin. Regulations throughout the world do not consider the combined effects of mycotoxins. However, several surveys have reported the natural co-occurrence of mycotoxins from all over the world. Most of the published data has concerned the major mycotoxins aflatoxins (AFs), ochratoxin A (OTA), zearalenone (ZEA), fumonisins (FUM) and trichothecenes (TCTs), especially deoxynivalenol (DON). Concerning cereals and derived cereal product samples, among the 127 mycotoxin combinations described in the literature, AFs+FUM, DON+ZEA, AFs+OTA, and FUM+ZEA are the most observed. However, only a few studies specified the number of co-occurring mycotoxins with the percentage of the co-contaminated samples, as well as the main combinations found. Studies of mycotoxin combination toxicity showed antagonist, additive or synergic effects depending on the tested species, cell model or mixture, and were not necessarily time- or dose-dependent. This review summarizes the findings on mycotoxins and their co-occurrence in various foods and feeds from all over the world as well as in vitro experimental data on their combined toxicity.

Fusarium proliferatum and fumonisin B1 co-occur with Fusarium species causing Fusarium Head Blight in durum wheat in Italy

Fusarium Head Blight caused by phytopathogenic Fusarium spp. with Fusarium graminearum as main causal agent is a major disease of durum wheat ( Triticum durum Desf.). Mycotoxins in wheat are dominated by trichothecenes B. Fumonisins have only occasionally been reported from wheat; their occurrence was attributed to Fusarium proliferatum and Fusarium verticillioides . We investigated kernels of durum wheat grown in Italy in 2008 - 2010 for colonization with Fusarium spp. and for the content of Fusarium mycotoxins. Fungal biomass was determined using species-specific qPCR and mycotoxins were quantified by HPLC-MS/MS. Fusarium graminearum and Fusarium culmorum were dominating Fusarium species, followed by Fusarium poae, Fusarium tricinctum, and Fusarium proliferatum . No Fusarium verticillioides DNA was found. Toxicologically relevant levels of deoxynivalenol and nivalenol but no trichothecenes A were detected. Enniatins, fumonisin B1 and beauvericin were present in grain in all three years. Based on these results and on the evaluation of previous published reports, we hypothesize that low levels of fumonisins commonly occur in wheat grains produced in warm climate; they may remain undetected as long as mycotoxin monitoring programs for wheat do not include fumonisins. The only relevant source of fumonisins in wheat grain appears to be Fusarium proliferatum.

Mycotoxin occurrence in maize produced in Northern Italy over the years 2009–2011: focus on the role of crop related factors

The occurrence of mycotoxins associated with Fusarium spp. and Aspergillus flavus in Northern Italy, and the role of cropping systems, were investigated on 140 field samples collected over the years 2009–2011. Samples were analysed for fumonisins B 1 and B 2 (FBs), aflatoxins B 1 , B 2 , G 1 and G 2 (AFs), deoxynivalenol (DON) and zearalenone (ZEN) using validated analytical methods. Information on: maize hybrid, preceding crop, tillage applied, mineral nutrition, pest and disease control, severity of European Corn Borer (ECB) attack, sowing and harvesting dates, kernel moisture at harvesting and longitude of the sampled province, were also collected. During this period there were distinct differences in FBs and AFs concentrations between years and geographic origins, and very low contamination with DON and ZEN was always found. The incidence of AFs exceeded 75% across all samples, and was almost 100% for FBs. The meteorological trends were quite different in the 3 years surveyed. 2009 was the coldest in June and the warmest in August, 2010 the most humid, and in 2011 cold weather occurred during flowering and dry conditions during ripening. The run of a logistic equation with the backward stepwise approach selected three parameters, (seeding week, ECB severity and longitude of sampling province) to predict AFB 1 contamination and four parameters (year, sowing week, ECB severity and longitude of sampling province) to predict FB contamination. The internal validation gave good results, with 76% correct predictions. The probability of harvesting maize with more than 5 µg kg -1 of AFB 1 varied between 86 and 5%, and the probability of harvesting maize with more than 4,000 µg kg -1 of FBs varied between 81 and 2%, respectively, for conducive and non-conducive environments. Therefore, considerable variability was found even if a limited area and only 3 years were considered.

Analysis of the expression of genes related to oxylipin biosynthesis in fusarium verticillioides and maize kernels during their interaction

Fusarium verticillioides is a pathogen that, nevertheless often asymptomatic, may cause ear and stalk rot in maize. F. verticillioides produces, under suitable environmental conditions, large amount of fumonisins, which is potential carcinogenic to humans and animals being classified as IARC2B. Recent studies demonstrated that the pathogen and the host exchange an oxylipin-based cross talk during their interaction. In this study, we aimed to investigate whether environmental conditions, namely water activity at 0.90 and 20°C, which are limiting for the pathogen development, may affect maize/fungal oxylipin genes expression profile during their interaction. Herein we showed that fungal Fvlds1-3, Fvlox, Zmlox3 and the maize defense-related ZmPR1 significantly changed their expression after infection at 0.90 aw and 20°C. Moreover, the expression of the maize genes peaked subsequently the peak of fungal genes expression. We suggest that, under these experimental conditions, the plant and the pathogen coordinated reciprocally oxylipin genes expression. This kind of modulation of fungal and plant gene expression was suggestive of the “zig zag model” as proposed for other plant-pathogen interaction system.

Influence of water activity and anti-fungal compounds on development and competitiveness of Fusarium verticillioides

This investigated the roles of water activity (a w ) and fungicides on the competitiveness of two Fusarium verticillioides strains against other spoilage fungi commonly present in maize ( F. proliferatum, Aspergillus niger, A. flavus, A. ochraceus and Penicillium verrucosum ). Fungal strains were inoculated on artificial media containing maize flour. The effects were determined of three a w levels (0.99, 0.98 and 0.95) and three fungicides (tebuconazole, procloraz and prothioconazole) on fungal interactions, the Index of Dominance (I D ) of isolates and fumonisin B 1 +B 2 (FBs) production. The two strains of F. verticillioides showed similar behaviour in conditions where water was freely available (0.99 a w ); at 0.98 and 0.95 a w both F. verticilliodes strains had the lowest total I D scores (8–6 and 10–12, respectively). They showed the same ability to compete against other fungi having the highest I D scores against P. verrucosum and A. ochraceus and the lowest against A. niger and A. flavus. The lowest water activity gave (0.95 a w ) was the most conducive for fumonisin production with significant differences to 0.98 and 0.99 a w . In a co-inoculation experiment, only FBs production from P. verrucosum was greater in the presence of the F. verticilliodes strains other fungi. The use of fungicides reduced Indices of Dominancy (I D ) for both F. verticilliodes strains. A significant reduction in F. verticilloides growth was observed when combining water stress and fungicide treatments. This information provides increased understanding of the colonisation patterns of F. verticillioides in relation to other mycobiota and to both environmental and chemical stresses, and has implications in relation to future climate change scenarios.

Pathogenicity and potential toxigenicity of seed-borne Fusarium species on soybean and pea.

The effect of 15 Fusarium species on seed germination and early plant development was examined in a laboratory study, together with the potential toxigenicity of selected isolates and the possibility of T-2 toxin production on soybean and pea grain. In germination tests, 33 out of 47 isolates of Fusarium chlamydosporum, F. pseudograminearum, F. sporotrichioides, F. crookwellense, F. verticillioides, F. equiseti, F. semitectum, F. solani, F. poae, F. sambucinum and F. compactum significantly reduced the number of normal soybean seedlings, while only six out of 48 isolates of F. sporotrichioides, F. semitectum and F. chlamydosporum significantly reduced the number of normal pea seedlings. When inoculated on plants grown in Hoagland's media, nearly all Fusarium isolates caused necrosis of soybean and pea root, but neither of them significantly reduced shoot and root dry mass of pea plants, or shoot dry mass of soybean plants. Amplification of tri5 and FUM1 genes, required for trichothecene and fumonisin biosynthesis, was carried out by PCR in 45 Fusarium isolates from soybean and 40 isolates from pea. Positive tri5 PCR reaction was recorded in 19 isolates of F. sporotrichioides, F. crookwellense, F. pseudograminearum, F. poae, F. sambucinum, F. culmorum, F. equiseti and F. chlamydosporum. Positive FUM1 PCR reaction was recorded in 35 out of 38 F. verticillioides and F. proliferatum isolates. The content of T-2 toxin produced by eight F. sporotrichioides isolates inoculated on autoclaved soybean, pea and barley grain ranged from 69.4 to 2595.5 μg/kg. No significant differences were determined between T-2 toxin production on soybean and barley grain, nor on pea and barley grain.

Role of the European corn borer (Ostrinia nubilalis) on contamination of maize with 13 Fusarium mycotoxins

The European corn borer (ECB) plays an important role in promoting Fusarium verticillioides infections and in the consequent fumonisin contamination in maize grain in temperate areas. The objective of this study was to evaluate whether the ECB feeding activity could also affect the occurrence of emerging mycotoxins in maize kernels. During the 2008–10 period, natural infestation of the insect was compared, in field research, with the protection of infestation, which was obtained by using an entomological net. The ears collected in the protected plots were free from ECB attack, while those subject to natural insect attacks showed a damage severity that varied from 10% to 25%. The maize samples were analysed by means of an LC-MS/MS-based multi-mycotoxin method, which led to the detection of various metabolites: fumonisins (FUMs), fusaproliferin (FUS), moniliformin (MON), bikaverin (BIK), beauvericin (BEA), fusaric acid (FA), equisetin (EQU), deoxynivalenol (DON), deoxynivalenol-3-glucoside (DON-3-G), zearalenone (ZEA), culmorin (CULM), aurofusarin (AUR) and butenolide (BUT). The occurrence of mycotoxins produced by Fusarium spp. of Liseola section was affected significantly by the ECB feeding activity. The presence of ECB injuries increased the FUMs from 995 to 4694 µg kg–1, FUS from 17 to 1089 µg kg–1, MON from 22 to 673 µg kg–1, BIK from 58 to 377 µg kg–1, BEA from 6 to 177 µg kg–1, and FA from 21 to 379 µg kg–1. EQU, produced by F. equiseti section Gibbosum, was also increased by the ECB activity, by 1–30 µg kg–1 on average. Instead, the content of mycotoxins produced by Fusarium spp. of Discolor and Roseum sections was not significantly affected by ECB activity. As for FUMs, the application of a strategy that can reduce ECB damage could also be the most effective solution to minimise the other mycotoxins produced by Fusarium spp. of Liseola section.

Efficacy of gaseous ozone treatment on spore germination, growth and fumonisin production by Fusarium verticillioides in vitro and in situ in maize

The objective of this study was to examine the effect of gaseous ozone (O3) at 100 and 200 ppm concentration, applied for 30 or 60 min (flow rate 6 L/min), on in vitro germination, growth and fumonisin (FUM) production by Fusarium verticillioides at different water activity (aw) conditions and the in situ effects after O3 treatment on fungal populations and FUM contamination of maize inoculated with F. verticillioides and stored at different marginal aw levels (0.92, 0.88) for 15 and 30 days. In vitro conidial germination appeared to be completely inhibited immediately after treatment (24 h) regardless of O3 exposure and aw level used. However, storage of spores resulted in recovery of germination over 8–10 days incubation to control levels at 0.98 and 0.94 aw. FUM production (FUMB1, FUMB2, FUMB3) after the germination of conidia treated with 100 or 200 ppm O3 was significantly higher than the controls. There was little effect of O3 treatment on mycelial extension of F. verticillioides. However, storage of the O3 exposed colonies for 10 days showed FUM contamination to be reduced when compared with the untreated controls. Maize grain adjusted to marginal aw levels (0.88, 0.92 aw) for growth of this mycotoxigenic species was inoculated with F. verticillioides conidia and exposed to these concentrations of O3 for 60 min. Immediately after treatment, the total fungal CFUs on the maize grain was significantly reduced. After storage for 15 and 30 days production of FUMB1 + FUMB2 was not detected in the control and O3 treatments at 0.88 aw. At 0.92 aw, there was FUM production in the controls but little in the O3 treatments. The implications of using gaseous O3 as a control strategy for minimising mycotoxin contamination of cereals are discussed.

Aspergillus spp. and their secondary metabolite production in grape berries from Slovakia.

Occurrence of Aspergillus spp. in grapes from Slovak has been surveyed during 2 years, to assess their ability to produce secondary metabolites, in vitro and in berries. A large number of Aspergillus spp., including A. flavus , A. japonicus , A. niger , A. carbonarius and A.ibericus , have been identified, and strains randomly selected and analysed to verify their potential ability to produce secondary metabolites. A broad spectrum of fungal metabolites has been observed in vitro and have been analysed using HPLC-MS/MS. Aspergillus niger , the most frequently isolated species, produced ochratoxin A (in a range from 104 to 1745 µg L-1) and fumonisin B2 (93 µg L-1). Aspergillus carbonarius produced ochratoxin A in the range 138 to 2031 µg L-1. Ochratoxin A and fumonisins were not detected in grape berries. Other secondary metabolites, including emodin, 3-nitropropionic acid, kojic acid and malformin C, were also detected at different concentrations in berries, but their occurrence was dependant on the geographic area of origin and on the year of berry collection.

Presence of Fusarium toxins in maize from Autonomous Province of Vojvodina, Serbia

Fusarium toxins are recognized as worldwide concern since those contaminants may potentially affect human and animal health and could also be a cause of great economical losses. The aim of this study was to determine the presence of the following Fusarium toxins: fumonisins (FUMs), deoxynivalenol (DON), zearalenone (ZEA) and sum of T-2/HT-2 toxins in maize. A total of 90 samples were collected during the harvest 2012 from four different maize growing areas in Autonomous Province of Vojvodina, Serbia. Analysis showed that 100%, 53.3% and 2.22% of examined maize samples were contaminated with FUMs, T-2/HT-2 and DON with median values of 1606, 35.3 and 650 μg/kg, respectively. None of the maize samples was contaminated with ZEA. Differences in the occurrence of investigated Fusarium toxins could be explained by different conditions required for their growth and synthesis of the toxins. Maize growing season 2012 was characterized by drought conditions. Hot and dry weather conditions were particularly favorable for FUMs production. This is the first report of the natural co-occurrence of FUMs, T-2/HT-2, ZEA and DON in maize from Serbia.

Evaluation of the increase of risk for public health related to a possible temporary derogation from the maximum level of deoxynivalenol, zearalenone and fumonisins for maize and maize products

The European Food Safety Authority (EFSA) was asked to deliver a scientific statement on the increase of risk for public health related to a possible temporary derogation from the maximum level (tML) of deoxynivalenol (DON), fumonisins (FUMO) and zearalenone (ZON) in maize and maize products. EFSA relied on occurrence data reflecting levels of these mycotoxins in the 2013 maize harvest. Depending on the mycotoxin, mean levels estimated considering tMLs were increased by a factor comprised between 7.6 and 27 % in maize and maize milling fractions, and up to 99 % in some processed maize-based products, compared to levels estimated considering current ML. Chronic exposure levels estimated across the population groups – representing different age classes and countries – were increased by a factor up to 17 % for fumonisins, 20 % for deoxynivalenol and 83 % for zearalenone. The tolerable daily intake (TDI) for zearalenone set by EFSA at 0.25 µg/kg body weight (b.w.) per day, and the group provisional maximum tolerable daily intake (PMTDI) of 1 and 2 µg/kg b.w. per day set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) for deoxynivalenol and fumonisins, were used as chronic health based guidance values (HBGV). For all three mycotoxins these values were exceeded in at least one age group when considering the current ML, reflecting a health concern. When considering the tMLs, percentages of consumers in the age groups with the highest exposures exceeding chronic HBGVs increased from 9.2 to 9.8 % for zearalenone, from 47 to 48 % for fumonisins and from 52 to 54 % for deoxynivalenol. Acute exposure scenarios resulted in exceedance of the group acute reference dose (ARfD) of 8 µg/kg b.w. established by JECFA for DON, with up to 1.2 % of the consumption days above the group ARfD with the current ML, and up to 8.1 % with the tML. This assessment, mainly based on French data, may lack representativeness for the European situation.

Changes in the Concentration of Fumonisins in Forage Rice during the Growing Period, Differences among Cultivars and Sites, and Identification of the Causal Fungus

To clarify the changes in rice fumonisin (FUM) concentrations, we conducted field cultivation of 10 forage rice cultivars and inoculation with fumonisin-producing fungal isolates. We cultivated 10 forage rice cultivars at the NARO Institute of Livestock and Grassland Science and one cultivar at two additional farmland sites in Japan in 2011 and 2012. Fusarium fujikuroi, which primarily infects plants shortly after heading, was inoculated on rice just after heading, and we sampled heads at the yellow-ripe and full-ripe stages to assess FUM concentrations. We found differences among cultivars in the FUM concentration and differences among the sites for the same cultivar, but no cultivar had high levels in leaves and stems. Fusarium fujikuroi was the main fumonisin producer. The FUM concentration in heads increases from <1 to 4760 μg/kg DM after the yellow-ripe stage. To control FUM levels, it is necessary to select low-FUM cultivars and manage the cultivation environment.

TRICHODERMA HARZIANUM T22 INDUCES IN MAIZE SYSTEMIC RESISTANCE AGAINST FUSARIUM VERTICILLIOIDES

SUMMARY Fusarium verticillioides is one of the most common plant pathogenic fungi affecting maize causing ear and kernel rot. Nearly the totality of the fungal strains are able to produce mycotoxins known as fumonisins at very different levels. However, information on the ability of the biocontrol fungus Trichoderma harzianum to induce systemic resistance in maize against F. verticillioides is still lacking. We now show that, upon root colonization by T. harzianum, F. verticillioides consistently reduces maize disease symptoms. The enhanced activation of SA- and JA/ ET-dependent defence responses indicates that resistance in maize is caused by a better perception of the fungal pathogen due to the effect of Trichoderma inocula. Seed biopriming with T. harzianum could be a useful strategy to control F. verticillioides infection and fumonisin accumulation under field conditions.

A Review on Mycotoxins in Food and Feed: Malaysia Case Study.

Fungi are distributed worldwide and can be found in various foods and feedstuffs from almost every part of the world. Mycotoxins are secondary metabolites produced by some fungal species and may impose food safety risks to human health. Among all mycotoxins, aflatoxins (AFs), ochratoxin A (OTA), trichothecenes, deoxynivalenol (DON and T-2 toxin), zearalenone (ZEN), and fumonisins (FMN) have received much attention due to high frequency and severe health effects in humans and animals. Malaysia has heavy rainfall throughout the year, high temperatures (28 to 31 °C), and high relative humidity (70% to 80% during wet seasons). Stored crops under such conditions can easily be contaminated by mycotoxin-producing fungi. The most important mycotoxins in Malaysian foods are AFs, OTA, DON, ZEN, and FMN that can be found in peanuts, cereal grains, cocoa beans, and spices. AFs have been reported to occur in several cereal grains, feeds, nuts, and nut products consumed in Malaysia. Spices, oilseeds, milk, eggs, and herbal medicines have been reported to be contaminated with AFs (lower than the Malaysian acceptable level of 35 ng/g for total AFs). OTA, a possible human carcinogen, was reported in cereal grains, nuts, and spices in Malaysian market. ZEN was detected in Malaysian rice, oat, barley, maize meal, and wheat at different levels. DON contamination, although at low levels, was reported in rice, maize, barley, oat, wheat, and wheat-based products in Malaysia. FMN was reported in feed and some cereal grains consumed in Malaysia. Since some food commodities are more susceptible than others to fungal growth and mycotoxin contamination, more stringent prevention and control methods are required.

Lipid metabolism of commercial layers fed diets containing aflatoxin, fumonisin, and a binder

Aflatoxins (AF) and fumonisins (FU) are a major problem faced by poultry farmers, leading to huge economic losses. This experiment was conducted to determine the effects of AF (1 mg/kg of feed) and FU (25 mg/kg of feed), singly or in combination, on the lipid metabolism in commercial layers and investigate the efficacy of a commercial binder (2 kg/t of feed) on reducing the toxic effects of these mycotoxins. A total of 168 Hisex Brown layer hens, 37 wk of age, were randomized into a 3 × 2 + 1 factorial arrangement (3 diets with no binder containing AF, FU, and AF+FU; 3 diets with binder containing AF, FU, and AF+FU; and a control diet with no mycotoxins and binders), totaling 7 treatments. The hens contaminated with AF showed the characteristic effects of aflatoxicosis, such as a yellow liver, resulting from the accumulation of liver fat, lower values of plasma very low-density lipoprotein and triglycerides, and higher relative weight of the kidneys and liver. Hepatotoxic and nephrotoxic effects of FU were not observed in this study. On the other hand, the FU caused a reduction in small intestine length and an increase in abdominal fat deposition. The glucan-based binder prevented some of the deleterious effects of these mycotoxins, particularly the effects of AF on hepatic lipid metabolism, kidney relative weight, and FU in the small intestine.

The occurrence of mycotoxins in wheat from western Romania and histopathological impact as effect of feed intake

BackgroundThe goal of this study has been to evaluate the extent of mycotoxins contamination and their co-occurrence in wheat grain intended for animal feed. A total of 52 wheat samples were collected from the harvest of two consecutive years (2010, 2011) from two counties (Timis and Arad) located in Western Romania and the presence of ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZON) and fumonisins (FUMO) was determined by enzyme-linked immunosorbent assay (ELISA). In order to evaluate the toxicological impact of mycotoxins, naturally contaminated wheat samples were administered in rats feed for one month.ResultsThe mycotoxin with the highest incidence in wheat samples was DON due to agro-climatic conditions typical for the west part of Romania. DON was found in 73.08% of samples harvested in 2010 and the highest level of contamination was 3390 ppb. The incidence of DON in sample from 2011 was lower than those of 2010, with a frequency of occurrence of 19.23%. The occurrence of ZON was in the range 69.23–76.92%, with an average value of 187.74 ppb. The OTA content in wheat was below the maximum tolerable limit established by EU Commission regulation for feed legislation (250 ppb). For FUMO the lowest percentage of positive samples was registered (15.38% in wheat sample harvested in 2010 and 11.54% positive samples in 2011). With respect to the co-occurrence of Fusarium mycotoxins, the results proved that ZON was found as a co-contaminant together with DON, especially when climatic conditions for development of fungus are favorable (high air humidity). The differences recorded between investigated localities and their classifications according to the mycotoxin kind and year of harvest were carried out by principal components analysis (PCA). The histopathological and immunohistochemical evaluation performed by hematoxylin and eosin (HE) staining technique as well as by assessing the vascular endothelial growth factor (VEGF) revealed significant modification of kidney, liver and spleen cells in the case of DON and FUMO. In terms of toxicity induced by OTA and ZON it was highlighted mixed normal and necrotic areas in liver, while histological assessment revealed normal VEGF expression in kidneys.ConclusionsAlthough none of the analyzed samples exceeding the stipulated maximum limits for cereals used as feed, a high incidence of mycotoxins produced by Fusarium species have been recorded (DON and ZON) in wheat samples harvested in Western Romania. Also, histopathological evaluation revealed significant tissue lesions in liver and kidney of rats after one month of feeding with natural contaminated wheat.