Assessment of dietary exposure to deoxynivalenol and fumonisin in the population of infants and toddlers in Turkey.

This study aims to estimate dietary exposure to deoxynivalenol and fumonisins (FBs) of infants and toddlers in Turkey. A total of 75 processed cereal-based foods intended for infants and toddlers collected between July and October 2018, were analysed by high performance liquid chromatography (HPLC). DON was determined in 21.3% of samples with mean middle bound (MB) level of 28.4 µg/kg. Of the 16 quantifiable samples, only one showed values above 200 µg/kg. Fumonisin B1 (FB1) was detected at quantifiable levels only in three samples, while FB2 was not found in any sample. Estimated mean MB chronic dietary exposures to DON in infants and toddlers were 0.161 and 0.118 µg/kg b.w. per day, while 95th percentile (P95) MB exposures to DON were estimated at 0.564 and 0.414 µg/kg b.w. per day, respectively. Mean MB dietary exposures to FBs for infants and toddlers, respectively, were 0.093 and 0.068 µg/kg b.w. per day; P95 exposure estimates were 0.079 and 0.058 µg/kg b.w. per day. Both for DON and FBs, mean and P95 exposures of infants and toddlers did not exceeded the threshold level of 1 µg/kg b.w. per day and are therefore not of health concern.

Fast and sensitive detection of mycotoxins in wheat using microfluidics based Real-time Electrochemical Profiling.

The objective of the study has been the development of a new sensing platform, called Real-time Electrochemical Profiling (REP) that relies on real-time electrochemical immunoassay detection. The proposed REP platform consists of new electrode arrays that are easy to fabricate, has a small imprint allowing microfluidic system integration, enables multiplexed amperometric measurements and performs well in terms of electrochemical immunoassay detection as shown through the deoxynivalenol detection assays. The deoxynivalenol detection has been conducted according to an optimised REP assay protocol using deoxynivalenol standards at varying concentrations and a standard curve was obtained (y=-20.33ln(x)+124.06; R(2)=0.97) with a limit of detection of 6.25 ng/ml. As both ELISA and REP detection methods use horse radish peroxidase as the label and 3.3',5.5'-Tetramethylbenzidine as the substrate, the performance of the REP platform as an ELISA reader has also been investigated and a perfect correlation between the deoxynivalenol concentration and the current response was obtained (y=-14.56ln(x)+101.02; R(2)=0.99). The calibration curves of both assays have been compared to conventional ELISA tests for confirmation. After assay optimisation using toxin spiked buffer, the deoxynivalenol detection assay has also been performed to detect toxins in wheat grain.

Prevention of Fusarium mycotoxin contamination by breeding and fungicide application to wheat.

The two main possibilities for decreasing toxin contamination were investigated in this paper. In the breeding section, we found that for resistance evaluation the ratio of Fusarium-damaged kernels is more important as this has a closer correlation with the deoxynivalenol (DON) content than the extent of Fusarium head blight (FHB). A high variability was found among lines from the non-Fusarium programme. A 50% decrease of DON contamination could be achieved by a simple and consequent resistance control. The tests with the variety candidates proved the same; therefore, the resistance screening for variety registration is an effective means to stop the spreading of highly susceptible genotypes. The resistance breeding programme showed an even larger DON decrease related to regular susceptible control varieties. Fungicide treatments were generally only weakly effective. However, it was shown that the testing methodology was poor, and with the optimal coverage spraying as much as 90% reduction of DON on small plot tests can be achieved. A farm-scale technology was also developed where the DON reduction as a mean for 3 years was higher than 70%, more than double the regular praxis data. To stabilize this efficacy, we need the most powerful fungicides, a nearly horizontal spraying of heads (like Turbo FloodJet nozzles) that receive the necessary coverage and so enough active ingredient to protect heads and the spraying technology should be kept rigorously. A combination of resistance and fungicide application can reduce DON contamination levels to below the European Union limit of 1.25 mg kg(-1) for levels which would otherwise be around 8-10 mg kg(-1). We think that this will solve most of the problems.

Mass spectrometric evidence for demethylated homologs occurring at trace levels in trichothecene standards.

Compounds with molecular weights 14 a.m.u. lower than their corresponding parent compounds have been detected in trichothecene standards during gas chromatography-mass spectrometry analysis. The positive ion chemical ionization mass spectra indicated that these compounds were trichothecene homologs lacking a methyl group on the isovaleroxy substituent at the C-8 position. Demethylated derivatives have been found in the standards of T-2, HT-2, and T-2 triol prepared in our laboratory and those obtained from a commercial source.