Cereal Samples Research Articles

Rapid UHPLC-MS metabolite profiling and phenotypic assays reveal genotypic impacts of nitrogen supplementation in oats

IntroductionOats (Avena sativa L.) are a whole grain cereal recognised for their health benefits and which are cultivated largely in temperate regions providing both a source of food for humans and animals, as well as being used in cosmetics and as a potential treatment for a number of diseases. Oats are known as being a cereal source high in dietary fibre (e.g. β-glucans), as well as being high in antioxidants, minerals and vitamins. Recently, oats have been gaining increased global attention due to their large number of beneficial health effects. Consumption of oats has been proven to lower blood LDL cholesterol levels and blood pressure, thus reducing the risk of heart disease, as well as reducing blood-sugar and insulin levels.ObjectivesOats are seen as a low input cereal. Current agricultural guidelines on nitrogen application are believed to be suboptimal and only consider the effect of nitrogen on grain yield. It is important to understand the role of both variety and of crop management in determining nutritional quality of oats. In this study the response of yield, grain quality and grain metabolites to increasing nitrogen application to levels greater than current guidelines were investigated.MethodsFour winter oat varieties (Mascani, Tardis, Balado and Gerald) were grown in a replicated nitrogen response trial consisting of a no added nitrogen control and four added nitrogen treatments between 50 and 200 kg N ha−1 in a randomised split-plot design. Grain yield, milling quality traits, β-glucan, total protein and oil content were assessed. The de-hulled oats (groats) were also subjected to a rapid Ultra High Performance Liquid Chromatography—Mass Spectrometry (UHPLC-MS) metabolomic screening approach.ResultsApplication of nitrogen had a significant effect on grain yield but there was no significant difference between the response of the four varieties. Grain quality traits however displayed significant differences both between varieties and nitrogen application level. β-glucan content significantly increased with nitrogen application. The UHPLC-MS approach has provided a rapid, sub 15 min per sample, metabolite profiling method that is repeatable and appropriate for the screening of large numbers of cereal samples. The method captured a wide range of compounds, inclusive of primary metabolites such as the amino acids, organic acids, vitamins and lipids, as well as a number of key secondary metabolites, including the avenanthramides, caffeic acid, and sinapic acid and its derivatives and was able to identify distinct metabolic phenotypes for the varieties studied. Amino acid metabolism was massively upregulated by nitrogen supplementation as were total protein levels, whilst the levels of organic acids were decreased, likely due to them acting as a carbon skeleton source. Several TCA cycle intermediates were also impacted, potentially indicating increased TCA cycle turn over, thus providing the plant with a source of energy and reductant power to aid elevated nitrogen assimilation. Elevated nitrogen availability was also directed towards the increased production of nitrogen containing phospholipids. A number of both positive and negative impacts on the metabolism of phenolic compounds that have influence upon the health beneficial value of oats and their products were also observed.ConclusionsAlthough the developed method has broad applicability as a rapid screening method or a rapid metabolite profiling method and in this study has provided valuable metabolic insights, it still must be considered that much greater confidence in metabolite identification, as well as quantitative precision, will be gained by the application of higher resolution chromatography methods, although at a large expense to sample throughput. Follow up studies will apply higher resolution GC (gas chromatography) and LC (reversed phase and HILIC) approaches, oats will be also analysed from across multiple growth locations and growth seasons, effectively providing a cross validation for the results obtained within this preliminary study. It will also be fascinating to perform more controlled experiments with sampling of green tissues, as well as oat grains, throughout the plants and grains development, to reveal greater insight of carbon and nitrogen metabolism balance, as well as resource partitioning into lipid and secondary metabolism.

Computational Method for the Identification of Molecular Metabolites Involved in Cereal Hull Color Variations.

Cereal hull color is an important quality specification characteristic. Many studies were conducted to identify genetic changes underlying cereal hull color diversity. However, these studies mainly focused on the gene level. Recent studies have suggested that metabolomics can accurately reflect the integrated and real-time cell processes that contribute to the formation of different cereal colors. In this study, we exploited published metabolomics databases and applied several advanced computational methods, such as minimum redundancy maximum relevance (mRMR), incremental forward search (IFS), random forest (RF) to investigate cereal hull color at the metabolic level. First, the mRMR was applied to analyze cereal hull samples represented by metabolite features, yielding a feature list. Then, the IFS and RF were used to test several feature sets, constructed according to the aforementioned feature list. Finally, the optimal feature sets and RF classifier were accessed based on the testing results. A total of 158 key metabolites were found to be useful in distinguishing white cereal hulls from colorful cereal hulls. A prediction model constructed with these metabolites and a random forest algorithm generated a high Matthews coefficient correlation value of 0.701. Furthermore, 24 of these metabolites were previously found to be relevant to cereal color. Our study can provide new insights into the molecular basis of cereal hull color formation.

Arsenic and cadmium concentrations in legumes and cereals grown in the North Central Province, Sri Lanka and assessment of their health risk

BackgroundA total of 181 samples of cereals and legumes, including mustard, maize, finger millet, sesame, cowpea/black-eyed pea, Urad dal /split bean, foxtail millet, long bean and green gram from the North Central Province of Sri Lanka were analysed for arsenic (As) and cadmium (Cd) levels using atomic absorption spectrophotometry (AAS).FindingsThe As and Cd level in each sample was not significantly different. The mean level was found to be 48.90 ± 34.63 μg/kg for As and 19.39 ± 9.508 μg/kg for Cd on weight basis.ConclusionNone of the foodstuffs studied contained As and Cd in levels exceeding the maximum permissible levels currently in force. Human health risk assessment of As and Cd in the foodstuffs was conducted and computed values indicated that there is no health risk due to consumption of the varieties studied. Nevertheless, the values, especially Total Hazard Quotient (THQ) emphasize the requirement of a comprehensive total diet study.

Masticatory behavior for different solid foods in preschool children according to their oral state.

Gradual introduction of solid foods in early childhood takes part in the maturation of mastication. The impact of any oral state alteration on food oral processing development is poorly documented for this age group. This study investigated the masticatory behavior in 3 to 6 year-old children with or without early childhood caries (ECC) for three solid foods of different textures. Twenty-one children with healthy oral state and 23 children with severe ECC were observed during complete mastication of calibrated samples of raw carrot, cheese and breakfast cereals. Food refusals and kinematic parameters (Ti: chewing time, Nc: number of cycles and Fq: chewing frequency) were used to assess children masticatory behavior. Oral Health-related Quality of Life and orofacial dysfunctions were evaluated using, respectively the early childhood oral health impact scale (ECOHIS) and the Nordic orofacial dysfunction test screening (NOT-S). Children suffering from ECC exhibited significantly higher ECOHIS and NOT-S scores, in particular for the mastication domain. Accordingly, lower chewing frequencies values were recorded in children with ECC (i.e., carrot Fq: 1.21 ± 0.20 vs 1.35 ± 0.22, p ≤ 0.01), as well as more frequent refusals for carrots. Kinematic parameters were shown to be repeatable in all children for successive samples of the same food, and tended to vary depending on the proposed food. Some masticatory behavior regulation according to food properties could already be present in preschool children. Children with ECC developed alternative behavioral strategies to overcome feeding difficulties. Further studies should investigate food bolus properties according to oral health, as well as nutritional issues. PRACTICAL APPLICATIONS: During childhood, the way solid foods are processed in the oral cavity to be safely swallowed and then digested in available nutrients, is poorly documented. In this study, preschool children have been shown to repeatedly adapt their masticatory behavior to a given food. The collection of various food boli as recorded at the moment of swallowing could then be considered in further food bolus properties research investigations. Moreover, this study suggested that children with altered dentition modified their masticatory kinematic parameters and developed alternative strategies, including food or texture selection, to overcome their feeding difficulties. The development of a mastication evaluation protocol could help medical professionals to detect children masticatory deficiencies and then propose diet adaptations. Considering the importance of food diversity in mastication development and maturation, food industries may consider to develop a range of texture adapted foods for young children, especially designed to gradually rehabilitate the masticatory function.

Health Effects of Chromium and Its Concentrations in Cereal Foods Together with Sulfur

The common cellular process of chromium and similar toxic elements are oxidative stress caused by reactive oxygen species, DNA damage, apoptosis, and cell death. Their cations have strong affinity for sulfur found in proteins, and thus they can deactivate the enzymes and stop or alter metabolic processes. In this study, absorption and toxicity of Cr were discussed taking into consider its solubility in water as well as chemical species and way of intake into body. Further, concentrations of total Cr and sulfur in cereal foods consumed commonly in Turkey were evaluated by a physiological approach. Among the studied 29 cereal samples, Cr concentrations in 17 of them (60%) were found to be higher (p 10−4). This evaluation is based on that chromium found in food and supplements is Cr(III).

Occurrence of emerging mycotoxins in cereals and cereal-based products from the Korean market using LC-MS/MS

ABSTRACTThe present study aimed to investigate the occurrence of emerging mycotoxins in cereals (n = 61) and cereal-based products (n = 36) collected from Korean market. First of all, using the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction method, and ultrahigh-pressure liquid chromatography (UPLC) with triple quadruple tandem mass spectrometry (MS/MS), we developed a simple and fast method for quantitative determination of eight emerging mycotoxins including alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN), beauvericin (BEA) and enniatins (ENs; ENA, ENA1, ENB and ENB1). The developed analytical method was validated in parameters of linearity, precision and accuracy. For UPLC-MS/MS analysis, the recoveries of emerging mycotoxins from spiked samples at three concentration levels ranged from 82.7% to 108.8% with RSDs between 0.4% and 14.7%. Analytical methods were applied to determine the contamination of mycotoxins in cereal and cereal-based product samples. Sixty-three of the total 97 samples were contaminated with at least one emerging mycotoxin. The maximum number of emerging mycotoxins observed in a single sample was six out of eight analytes. The highest level of contamination was detected in cereal at 70.9 μg/kg for alternariol monomethyl ether (AME). However, currently there is no international standard for emerging mycotoxins in food. Accordingly, it is necessary to establish a database of emerging mycotoxins contamination through continuous monitoring.

Regional Sub-Saharan Africa Total Diet Study in Benin, Cameroon, Mali and Nigeria Reveals the Presence of 164 Mycotoxins and Other Secondary Metabolites in Foods.

In the framework of the first multi-centre Sub-Saharan Africa Total Diet Study (SSA-TDS), 2328 commonly consumed foods were purchased, prepared as consumed and pooled into 194 composite samples of cereals, tubers, legumes, vegetables, nuts and seeds, dairy, oils, beverages and miscellaneous. Those core foods were tested for mycotoxins and other fungal, bacterial and plant secondary metabolites by liquid chromatography, coupled with tandem mass spectrometry. The highest aflatoxin concentrations were quantified in peanuts, peanut oil and maize. The mean concentration of the sum of aflatoxins AFB1, AFB2, AFG1 and AFG2 (AFtot) in peanut samples (56.4 µg/kg) exceeded EU (4 µg/kg) and Codex (15 µg/kg) standards. The AFtot concentration (max: 246.0 µg/kg) was associated with seasonal and geographic patterns and comprised, on average, 80% AFB1, the most potent aflatoxin. Although ochratoxin A concentrations rarely exceeded existing Codex standards, it was detected in unregulated foods. One palm oil composite sample contained 98 different metabolites, including 35.4 µg/kg of ochratoxin A. In total, 164 different metabolites were detected, with unspecific metabolites like asperglaucide, cyclo(L-pro-L-val), cyclo (L-pro-L-tyr), flavoglaucin, emodin and tryptophol occurring in more than 50% of composite samples. Aflatoxin B1 (AFB1), fumonisin B1 (FB1), sterigmatocystin (STC), ochratoxin A (OTA), citrinin (CIT) and many other secondary fungal metabolites are frequent co-contaminants in staple foods, such as maize and sorghum. Populations from North Cameroon and from Benin may, therefore, suffer chronic and simultaneous exposure to AFB1, FB1, STC, OTA and CIT, which are prevalent in their diet.

Determination of total concentration and bioaccessible fraction of metals in infant cereals by MIP OES

The present study provides information about the total concentration and bioaccessible fraction of metals Al, Ba, Bi, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Pb, Ti and Zn in nine different infant cereal samples. An in vitro digestion method was employed to evaluate the bioaccessibility. The determinations were performed by microwave induced plasma optical emission spectrometry (MIP OES). The bioaccessibility varied according to the type of infant cereal sample. The values of bioaccessible fraction (minimum and maximum) for Cu, Fe, Mn, Pb and Zn were 24–68, 1–10, 7–58, 24–100 and 1–7% of the total concentration, respectively. Al and Ti presented bioaccessibility in only two samples: 6% in the multicereal A and 14% in the rice and oat cereal B, respectively. The concentration of Ba, Bi, Cd, and Cr was below the limit of detection for the bioaccessibility method. The obtained concentrations were lower than the daily recommended intake for essential and toxic elements, with exception of Pb in the rice and oat A sample.

Metabarcoding targeting the EF1 alpha region to assess Fusarium diversity on cereals.

Fusarium head blight (FHB) is a major cereal disease caused by a complex of Fusarium species. These species vary in importance depending on climatic conditions, agronomic factors or host genotype. In addition, Fusarium species can release toxic secondary metabolites. These mycotoxins constitute a significant food safety concern as they have health implications in both humans and animals. The Fusarium species involved in FHB differ in their pathogenicity, ability to produce mycotoxins, and fungicide sensitivity. Accurate and exhaustive identification of Fusarium species in planta is therefore of great importance. In this study, using a new set of primers targeting the EF1α gene, the diversity of Fusarium species on cereals was evaluated using Illumina high-throughput sequencing. The PCR amplification parameters and bioinformatic pipeline were optimized with mock and artificially infected grain communities and further tested on 65 field samples. Fusarium species were retrieved from mock communities and good reproducibility between different runs or PCR cycle numbers was be observed. The method enabled the detection of as few as one single Fusarium-infected grain in 10,000. Up to 17 different Fusarium species were detected in field samples of barley, durum and soft wheat harvested in France. This new set of primers enables the assessment of Fusarium diversity by high-throughput sequencing on cereal samples. It provides a more exhaustive picture of the Fusarium community than the currently used techniques based on isolation or species-specific PCR detection. This new experimental approach may be used to show changes in the composition of the Fusarium complex or to detect the emergence of new Fusarium species as far as the EF1α sequence of these species show a sufficient amount of polymorphism in the portion of sequence analyzed. Information on the distribution and prevalence of the different Fusarium species in a given geographical area, and in response to various environmental factors, is of great interest for managing the disease and predicting mycotoxin contamination risks.

Selenium Content and/or T-2 Toxin Contamination of Cereals, Soil, and Children's Hair in Some Areas of Heilongjiang and Gansu Provinces, China.

It has been strongly suggested that selenium deficiency and T-2 contamination in cereals are responsible for the development of Kashin-Beck disease (KBD). In order to assess these risk factors of KBDin the internal and external environments, our team undertook a two-stage survey in some areas of Heilongjiang and Gansu Provinces, China. The selenium content in children's hair (293), cereal (192), and soil (46) samples were determined using the 2, 3-diamino-naphthalene fluorometric assay technique. The T-2 toxin contamination level in the cereal samples (704) was assayed using an ELISA kit. There were no clinical KBD cases identified in this survey. The selenium statuses of the children in all the investigated regions during the first phase were at the medium selenium nutrition level. During the second phase, the selenium status of the children in Weiyuan County, Ning County, and Shangzhi City was at the medium selenium nutrition level, at the edge of selenium deficiency, and selenium deficient, respectively. Furthermore, the selenium contents in the cereal and soil samples were low. During the first phase, the average T-2 toxin contamination level in the family staple food samples for all the investigated regions was about 10ng/g. However, the T-2 toxin contamination levels in eight homegrown corn samples were higher than 100ng/g. During the second phase, all the average T-2 toxin contamination levels in the flour and corn samples from the three investigated regions were less than 10ng/g. Risk factors that affect the prevalence of KBD still remain in the internal and external environments of some areas in Heilongjiang and Gansu Provinces.

Determination of Eight Sulfonylurea Herbicide Residues by LC/MS/MS Using a Sample Separation Technique with Ethyl Acetate.

Background: Sulfonylureas are an important group of systemic herbicides mainly used for the control of weeds in cereals and other crops in early growth stages of their cultivations. Sulfonylureas are characterized by their broad spectrum weed control and their good crop selectivity. Objective: In the present study, the determination of eight sulfonylureas has been tested in wheat flour by applying the SweEt multiresidue method modified for dry products. Method: The method involves sample preparation with extraction with ethyl acetate (EEA) and determination of the analytes with LC/MS/MS-electrospray ionization. Its performance was compared with the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. Both methods were validated in three fortification levels according to European Union requirements. Results: The proposed method gave acceptable results as far as validation criteria are concerned, while QuEChERS did not result in successful recoveries in the lowest validation level, which is equal to the respective maximum residue limits (MRLs). Conclusions: The obtained results showed that the tested method showed good separation, sensitivity, linearity, precision, and accuracy for quantitative and qualitative analysis of sulfonylurea herbicides in cereals at low levels, as required by legislation. The analytical techniques were successfully applied to different samples of cereals, and no residues were determined above the reporting limit, as established at the lowest concentration level of each analyte being validated with acceptable accuracy. Highlights: Low recoveries for QuEChERS in the concentrations equal to the MRL. Acceptable recoveries for the EEA method in all fortification levels. Correlation coefficients above 0.99. Positive findings only with EEA in real samples.

Phage-displayed nanobody based double antibody sandwich chemiluminescent immunoassay for the detection of Cry2A toxin in cereals

ABSTRACT In this study, we developed a double antibody sandwich chemiluminescent immunoassay (DAS-CLIA) based on phage-displayed nanobodies for the determination of Cry2A toxin. Nine phage-displayed nanobodies specifically to Cry2A were obtained from a naive nanobody library after four rounds of biopanning. The phage-displayed nanobody P2 with high affinity binding was selected as the detection antibody for the sensitive DAS-CLIA development. The proposed method exhibited high sensitivity with a limit of detection of 0.09 ng/mL, has a wide linear range for Cry2A toxin detection, in the range of 0.1–1000 ng/mL and negligible cross-reactivities to the other Bt toxins. The recoveries of Cry2A toxin spiked in cereal samples (rice, wheat, and corn) ranged from 82.7% to 118%, with a coefficient of variation of less than 10%. This study demonstrated that the DAS-CLIA procedure based on phage-displayed nanobodies may provide an alternative sensitive method for the detection of Bt toxins in agri-products.

Detection of deoxynivalenol (DON) using europium chelates and magnetic nanoparticles

ABSTRACT Background: Several immunoassay methods have been developed for the detection of DON in cereal. However, there has been no method based on Eu-chelate antibody-conjugated magnetic nanoparticles established. Methods: Indirect competition for DON detection was established by combining Eu-chelate and immunomagnetic separation. The immunocomplex was separated and washed by exposure to a magnetic field and treatment with enhancement solution; then, fluorescences were measured according to the number of europium ions dissociated. Results: The working concentrations ranged from 0.05 to 100 ng/mL, and the sensitivity was 0.5 μg/Kg in cereal. The intra–assay CVs of corn and wheat were 5.7% and 7.1%, respectively. The recovery rates obtained using cereal sample were 83.2%–120.0%. Conclusion: This study suggested that the Eu-chelate antibody-conjugated magnetic nanoparticles method was fast and sensitive in screening large quantities of samples, and could be used for detection of DON in cereal.

Potential Health Risk Assessment of Different Heavy Metals in Wheat Products.

In the present work, health risk of heavy metals such as As, Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn in Iranian urban and rural samples including wheat, wheat flour, bread, pasta and sweets were assessed. The real amount of heavy metals in target samples were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES) and atomic absorption spectroscopy (AAS). Wet ashing and hydride generation techniques were used in sample preparation step. Results demonstrated that heavy metal contaminations in cereal samples were significant. The average concentrations of heavy metals in wheat products were between 0.01 mg kg−1 to 46 mg kg−1. Finally, the health risk assessment results showed that heavy metal contents in rural samples were higher than those in urban samples. The risk of Cu and Zn was significant in two areas and risk of Cr and Cd was not significant.

Development of a noncompetitive idiometric nanobodies phage immumoassay for the determination of fumonisin B1

ABSTRACT Here we demonstrate a noncompetitive idiometric nanobodies phage immunoassay for the determination of FB1, utilizing two types of anti-idiotypic nanobody, that is specific for different epitopes within the hypervariable region of the primary mAb. Three alphatype anti-idiotypic nanobodies were obtained from a naive nanobodies phage-display library. A noncompetitive idiometric immunoassay was established with a combination of betatype anti-idiotypic nanobody and phage-displayed alphatype anti-idiotypic nanobody. The half-maximal saturation of the signal value (SC50) was 0.68 ng/mL, with the limit of detection (LOD) was 0.19 ng/mL. When the noncompetitive assay was compared to the competitive ELISA (LOD = 3.41 ng/mL), an over 17-fold improvement in sensitivity was observed. A correlation (R 2) was 0.988 between the data of the noncompetitive assay and LC–MS/MS for the determination of FB1 in cereal samples. The noncompetitive idiometric immunoassay would have a broad utility for monitoring small molecules in food and environment.

Quantum Dot-Labeled Immunochromatographic Test Strip for Rapid Detection of Ochratoxin A in Cereals

Objective:A quantum dot-labeled immunochromatographic test strip for the determination of ochratoxin A(OTA)in cereals was developed based on the competitive inhibition principle. Methods:Quantum dot antibody conjugates(QD-Ab)were prepared by coupling an carboxy-functionalized quantum dot(QD)with an ochratoxin A polyclonal antibody(Antibody,Ab)via the activated ester method;Different amounts of QD-Ab and working fluid were used to optimize the working conditions of the quantum dot-labeled immunochromatographic test strip;The effectiveness of the method was verified by a commercial kit. Results:When the molar ratio of QD to Ab was 1:10,the fluorescence characteristics of QD-Ab were the best;when QD-Ab and working fluid were added at 1,10 μL,respectively,the best results of quantum dot-labeled immunochromatographic test strips were obtained;The detection limit of the quantum dot-labeled immunochromatographic test strip in the assay buffer was 0.5 μg/L,and the detection limit of OTA in the cereal sample was 5 μg/kg,the entire detection process could be completed within 10 min;The quantum dot-labeled immunochromatographic test strip had good specificity and effectiveness. Conclusion:This assay is simple,rapid,and sensitivity. It can meet the requirements of on-site rapid detection of ochratoxin A in cereals.

Monitoring of nine pesticides in different cereal flour samples with high performance liquid chromatography-diode array detection

A method based on LLLE-DLLME-HPLC-DAD has been developed for the extraction and determination of nine multiclass pesticides from selected cereals.

Assessment of changes in the occurrence of Fusarium toxin and ochratoxin A in Poland related to extreme weather phenomena

Mycotoxins – substances harmful to humans, are ubiquitous in the environment. Mycotoxins are generated primarily by Penicilium, Aspergillus and Fusarium genus fungi. Their presence is associated with the unavoidable presence of mold fungi in the environment. The presently observed adverse climatic changes could negatively affect agriculture, causing erosion and loss of organic matter from soil, promulgation of pests and plant diseases, including those originating from pathogenic molds, and also migration of certain mold species into new regions, ultimately creating more favorable conditions for generation of mycotoxins. The purpose of this work was to investigate contamination of cereals in Poland with Fusarium and ochratoxin A. Elucidating a correlation between precipitation levels in the individual Provinces and reported levels of the investigated mycotoxins, referring to the generally available meteorological databases, would result in more efficient planning of sampling processes and focusing further preventive actions associated with establishing sampling plans for the following years. Investigations were performed on cereal and cereal product samples taken by the official foodstuffs inspection staff. Some 100 samples were taken annually in the 2009-2012 period (357 samples in total). Tests were performed using high performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS). Precipitation data were obtained from the Central Office of Statistics, based on data received from the Institute of Meteorology and Water Management. Analysis of the influence of precipitation levels during vegetation period on mycotoxin levels in the investigated foodstuffs was performed by associating each recorded content of deoxynivalenol (n=52, corresponding to 14.6% tested samples), zearalenone (n=30, 8.4%), total T-2 and HT-2 toxins (n=21, 5.9%) and ochratoxin A (n=88, 24.6%) above quantification limit with precipitation levels within the Province from which the sample originated. Deoxynivalenol and zearalenone levels show distinct variability corresponding with variability of precipitation levels, well reflecting the reported higher deoxynivalenol and zearalenone levels observed during the rainy years of 2011-2012. Variability in average ochratoxin A levels was not statistically significant. The relatively higher mycotoxin levels in 2009 may result from the heavy rainfall and flooding of 2007-2008. Dependence between the precipitation levels and number of samples showing levels above quantification limit has been also observed for deoxynivalenol. However, a similar analysis made for zearalenone and ochratoxin A does not point to any significant relationship. No data analysis was possible in reference to total T-2 and HT-2 toxins content due to the insufficient number of results available. However, it should be noted that 21% analyzed samples in 2009 contained T-2 and HT-2 levels above the quantification limit, with average of 8.9 μg/kg, whereas in 2010-2012 only one sample of the 263 tested contained contaminants in quantities above the quantification limit. The model used for forecasting presence of mycotoxins in cereals does not allow its practical application during routine generation of official control and monitoring plans on national scale. Notably, tests performed show that exceeding of maximum contamination levels occurred just incidentally, notwithstanding the adverse weather conditions. Further systematic collection of data on mycotoxin contamination of agricultural crops is required for effective continued investigations.

Multiannual occurrence of mycotoxins in feed ingredients and complete feeds for pigs in the Czech Republic

The aim of the study was to evaluate the individual and combined occurrence of mycotoxins in feed ingredients and complete feeds for pigs in the Czech Republic in the years 2013–2017. The samples were analysed for the occurrence of aflatoxins (AF), deoxynivalenol (DON), zearalenone (ZEA), ochratoxin A (OTA), fumonisins (FUM), and T-2/H-2 toxins. The mycotoxin most commonly found in maize and small cereal grain samples was deoxynivalenol (94% and 53%, respectively). Deoxynivalenol was also the most frequent mycotoxin in all types of swine feed. The most frequent mycotoxin combinations in the total number of samples were DON + ZEA (56.63%), DON + OTA (11.61%) and DON + sum of T2/HT2 (9.76%). The maximum values set by the European Commission for mycotoxin levels in feed ingredients and complete feeds were exceeded in the case of AFB1, deoxynivalenol, zearalenone, ochratoxin A and T-2/H-2 toxins. Our findings support the need for further monitoring of mycotoxins in feed ingredients and complete feeds for pigs in the Czech Republic.

Natural Occurrence of Beauvericin and Enniatins in Corn- and Wheat-Based Samples Harvested in 2017 Collected from Shandong Province, China.

Totals of 158 corn and corn-based samples and 291 wheat and wheat-based samples from Shandong province, China in 2017 were analyzed for five mycotoxins including beauvericin (BEA), enniatin A (ENA), enniatin A1 (ENA1), enniatin B (ENB), and enniatin B1 (ENB1) by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). BEA was the predominant toxin detected, followed by ENB, ENA1, ENA, and ENB1. Corn and corn-based samples were more easily contaminated by BEA with an average concentration of 65.26 µg/kg, compared with that in wheat and wheat-based samples (average = 0.41 µg/kg). Concentrations of BEA, ENA, and ENB1 in corn kernels, flours, and flakes were significantly different (Kruskal–Wallis Test, p < 0.05), as well as for BEA, ENA, ENB, and ENB1 in wheat kernels, flours, and noodles (Kruskal–Wallis test, p < 0.05). Furthermore, 59.5% (94/158) and 59.8% (174/291) corn- and wheat-based samples were co-contaminated by at least two mycotoxins, respectively. Positive correlations in concentrations were observed in corn between levels of ENA and ENB1, ENA and ENB, ENA1 and ENB1, as well as in wheat between BEA and ENA, BEA and ENA1, BEA and ENB, BEA and ENB1, ENA and ENA1, ENA and ENB, ENA and ENB1, ENA1 and ENB, ENA1 and ENB1, and ENB and ENB1. These results demonstrate that co-contamination of BEA and enniatins (ENNs) in corn- and wheat-based samples from Shandong, China is very common. More data on the contamination of five mycotoxins in cereal and cereal-based samples nationwide are needed.