A fast, easy-to-handle and cost-effective analytical method for 11 mycotoxins currently regulated in maize and other cereal-based food products in Europe was developed and validated for maize. The method is based on two extraction steps using different acidified acetonitrile–water mixtures. Separation is achieved using ultrahigh-performance liquid chromatography (UHPLC) by a linear water–methanol gradient. After electrospray ionisation, tandem mass spectrometric detection is performed in dynamic multiple reaction monitoring mode. Since accurate mass spectrometric quantification is hampered by matrix effects, uniformly [13C]-labelled mycotoxins for each of the 11 compounds were added to the sample extracts prior to UHPLC-MS/MS analysis. Method performance parameters were obtained by spiking blank maize samples with mycotoxins before as well as after extraction on six levels in triplicates. The twofold extraction led to total recoveries of the extraction steps between 97% and 111% for all target analytes, including fumonisins. The [13C]-labelled internal standards efficiently compensated all matrix effects in electrospray ionisation, leading to apparent recoveries between 88% and 105% with reasonable additional costs. The relative standard deviations of the whole method were between 4% and 11% for all analytes. The trueness of the method was verified by the measurement of several maize test materials with well-characterized concentrations. In conclusion, the developed method is capable of determining all regulated mycotoxins in maize and presuming similar matrix effects and extraction recovery also in other cereal-based foods.

Mycotoxins are natural contaminants produced by a range of fungal species. Their common occurrence in food and feed poses a threat to the health of humans and animals. This threat is caused either by the direct contamination of agricultural commodities or by a "carry-over" of mycotoxins and their metabolites into animal tissues, milk, and eggs after feeding of contaminated hay or corn. As a consequence of their diverse chemical structures and varying physical properties, mycotoxins exhibit a wide range of biological effects. Individual mycotoxins can be genotoxic, mutagenic, carcinogenic, teratogenic, and oestrogenic. To protect consumer health and to reduce economic losses, surveillance and control of mycotoxins in food and feed has become a major objective for producers, regulatory authorities and researchers worldwide. However, the variety of chemical structures makes it impossible to use one single technique for mycotoxin analysis. Hence, a vast number of analytical methods has been developed and validated. The heterogeneity of food matrices combined with the demand for a fast, simultaneous and accurate determination of multiple mycotoxins creates enormous challenges for routine analysis. The most crucial issues will be discussed in this review. These are (1) the collection of representative samples, (2) the performance of classical and emerging analytical methods based on chromatographic or immunochemical techniques, (3) the validation of official methods for enforcement, and (4) the limitations and future prospects of the current methods.

Sulfur dioxide (SO2) or sulfites are the most common preservatives used in winemaking. The level of total SO2 is subject to regulation. Currently, the regulatory determination of total SO2 (including sulfites) is done by the optimized Monier-Williams (OMW) method, which includes time-consuming distillation and titration steps. This paper describes the development and application of an alternative, rapid, straightforward, and reliable method for the determination of total sulfite in wine. In this method, a simple oxidation step using alkaline hydrogen peroxide (H2O2) solution is followed by ion chromatographic (IC) analysis of sulfate coupled with conductometric detection. Thirteen wines were analyzed in order to compare the in-sample oxidation method with the OMW-procedure. A t-test revealed satisfying compliance regarding sample preparation, i.e., alkaline H2O2 treatment and acidic distillation (OMW method). Comparable results were also obtained between IC analysis and acid/base titration. Our results indicate that the novel method (limit of quantification: 4 mg SO2 L(-1)) is well suited for the cost-efficient monitoring of regulatory limits.

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Aims A laboratory study was conducted to evaluate the influence of cocultivation of toxigenic Fusarium (F.) and Alternaria (A.) fungi with respect to growth and mycotoxin production. Methods and Results Fusarium culmorum Fc13, Fusarium graminearum Fg23 and two Alternaria tenuissima isolates (At18 and At220) were simultaneously or consecutively co‐incubated on wheat kernels in an in vitro test system. Fungal biomass was quantified by determining ergosterol content. Three Fusarium toxins (DON, NIV and ZON) and three Alternaria toxins (AOH, AME and ALT) were analysed by a newly developed HPLC/MS/MS method. In simultaneous cocultures, the fungal biomass was enhanced up to 460% compared with individual cultures; Alternaria toxins were considerably depressed down to <5%. Combining At18 and At220 with Fg23 inhibited the toxin production of both fungal partners. In contrast, Fc13 increased its DON and ZON production in competitive interaction with both A. strains. Conclusions The interfungal competitive effects aid the understanding of the processes of competition of both fungi in natural environments and the involvement of mycotoxins as antifungal factors. Significance and Impact of Study Cocultivation significantly affects fungal growth and mycotoxin production of phytopathogenic Alternaria and Fusarium strains. The impact of mycotoxins on the interfungal competition is highlighted.

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A method for the determination of the novel brominated flame retardant tetrabromobisphenol A bis(2,3-dibromopropylether), 1,1'-(isopropylidene)bis[3,5-dibromo-4-(2,3-dibromo-propoxy)-benzene] (TBBPA-dbpe), was developed. Technical TBBPA-dbpe was purified and the results of a thorough physical characterisation are reported. The application of APCI-MS is discussed and the fragmentation patterns are described. Quantification of TBBPA-dbpe was done by HPLC-DAD using external calibration. The validation of the method was accomplished using sediment and sewage sludge samples spiked with defined amounts of authentic TBBPA-dbpe. The average recovery rates of TBBPA-dbpe from spiked samples ranged from 35 to 91% (sediment) and from 57 to 98% (sewage sludge) depending on the respective extraction method. Pressurised fluid extraction (PFE) and fluidised bed extraction were superior to classical Soxhlet and sonication procedures and yielded recovery rates between 90 and 98% with relative standard deviations of 2%. The limits of detection (DTC), identification (ID) and determination (DTM) using HPLC-DAD were 10, 21 and 30 ng g(-1) in sediment and 22, 44 and 72 ng g(-1) in sewage sludge, respectively.

The role of mycotoxins in the microbial competition in an ecosystem or on the same host plant is still unclear. Therefore, a laboratory study was conducted to evaluate the influence of mycotoxins on growth and mycotoxin production of Fusarium and Alternaria fungi. Fusarium culmorum Fc13, Fusarium graminearum Fg23 and two Alternaria tenuissima isolates (At18 and At220) were incubated on wheat kernels supplemented with alternariol (AOH), tetramic acid derivates (TeA), deoxynivalenol (DON) and zearalenone (ZEA) in an in vitro test system. Fungal biomass was quantified by determining ergosterol content. Three Fusarium toxins (DON, nivalenol and ZEA) and three Alternaria toxins (AOH, alternariol methyl ether (AME) and altenuene) were analysed by HPLC-MS/MS. If Alternaria strains grew in wheat kernels spiked with Fusarium mycotoxins, their growth rates were moderately increased, their AOH and AME production was enhanced and they were simultaneously capable of degrading the Fusarium mycotoxins DON and ZEA. In contrast, both Fusarium strains behaved quite differently. The growth rate of Fc13 was not distinctly influenced, while Fg23 increased its growth in wheat kernels spiked with AOH. TeA depressed the ergosterol content in Fc13 as well as in Fg23. The DON production of Fc13 was slightly depressed, whereas the ZEA production was significantly increased. In contrast, Fg23 restricted its ZEA production. Both Fusarium strains were not capable of degrading the Alternaria mycotoxin AOH. Mycotoxins might play an important role in the interfungal competitive processes. They influence growth rates and mycotoxin production of the antagonistic combatants. The observed effects between phytopathogenic Alternaria and Fusarium strains and their mycotoxins aid the understanding of the complexity of microbial competitive behaviour in natural environments.