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Deoxynivalenol (DON) and its modified forms (3-, and 15-acetyl-DON, DON-3-glucoside) are commonly analysed by chromatographic methods. Indeed, coupled with proper extraction and clean-up, LC-MS represents the best approach for multi-mycotoxin measurements. On the other hand, immunochemistry-based methods are possibly able to detect a family of structurally related compounds, although the determination of single contributions is not possible so far. However, ELISA methods often lead to an apparent overestimation of the mycotoxins content because modified forms and matrix components can potentially cross-react with the antibodies (designed for the parent toxin). Several data about the possible cross-reactivity of commercial DON-detecting ELISA kit are reported in the literature so far. Data are commonly obtained in buffer solutions or in matrix-matched solutions, but comparison of a set of naturally incurred samples has never been reported. In the present work the accuracy of a commercial DON-detecting ELISA kit was evaluated on naturally incurred soft wheat (n = 15) and maize (n = 15), taking into account the matrix effect. Recovery was calculated considering the DON concentration found by LC-MS/MS and the total DON concentration, expressed as the sum of DON and its modified forms found by LC-MS/MS. The obtained data clearly show that, when 3-modified forms of DON occur in the sample, the ELISA kit does actually detect them, thus returning an apparent overestimation if only DON content is considered. When the ELISA recovery is calculated on the total DON content, the accuracy of the analysis increases and the variability decreases. According to our data, the ELISA kit seems to be a promising group detection tool for the accurate evaluation of DON and its modified forms, expressed as sum of DON, DON-3Glc and 3Ac-DON, for soft wheat and maize samples. [ABSTRACT FROM PUBLISHER]

A new chromatographic method is proposed for the analysis of aflatoxin M1in milk. The method is based on liquid–liquid extraction followed by LC-MS/MS analysis. Liquid–liquid extraction (LLE) is performed on the defatted milk plus sodium chloride by using ethyl acetate as an extraction solvent. Accuracy and precision were evaluated at the LOQ (15 ng kg–1) spiked sample as well as with three other different naturally contaminated reference materials. The mean overall recovery (n = 24) was 95% with a confidence interval of 1.9% and a CV% of 4.5%. The performance of the proposed method was compared with that of the Official ISO Method based on the use of immunoaffinity chromatography columns (IAC): LLE protocol could be considered a valid alternative to the LC-IAC. In general it showed better accuracy with lower data dispersion. Moreover, the sample preparation is very simple and straightforward, potentially being applicable as a high-throughput method which, on account of its simplicity and low cost, may be applied to the analysis of a large number of samples in the occasion of outbreaks of large-scale contamination. [ABSTRACT FROM PUBLISHER]

Fusarium mycotoxins are a relevant problem in the cereal supply chain at a worldwide level, with wheat, maize and barley being the main contaminated crops. Mould growth can happen in the pre-harvest phase and also during transport and storage due to ineffective drying conditions. Among Fusarium toxins, deoxynivalenol (DON) is considered the most important contaminant in wheat due to its widespread occurrence. In the last years the European Food Safety Authority (EFSA) and the European Commission have frequently expressed opinions on Fusarium toxins, setting limits, regulations and guidelines in order to reduce their levels in raw materials and food commodities. In particular, European legislation (Reg. 1881/2006) sets the maximum limit for DON in flour and bread as 750 and 500 µg kg−1 respectively. Relatively few studies have taken into account the loss of trichothecenes during processing, focusing on how processing factors may influence their degradation. In particular, the description of DON behaviour during bread-making is very difficult, since complex physico-chemical modifications occur during the transformation of the raw ingredients into the final product. In the present study, we studied how DON concentration may be influenced by modifying bread-making parameters, with a special emphasis on the fermentation and baking stages, starting from a naturally contaminated flour at both pilot and industrial scales. Exploiting the power of a Design of Experiments (DoE) approach to consider the great complexity of the studied system, the obtained model shows satisfying goodness-of-fit and prediction, suggesting that the baking step (time/temperature ranges) is crucial for minimizing native DON level in bread. [ABSTRACT FROM AUTHOR]

A selection is presented of fiber-optic and micro-optic devices that have been designed and tested for guaranteeing the quality and safety of typical foods, such as extra virgin olive oil, beer, and milk. Scattered colorimetry is used to authenticate various types of extra virgin olive oil and beer, while a fiber-optic-based device for UV-VIS-NIR absorption spectroscopy is exploited in order to obtain the hyperspectral optical signature of olive oil. This is done not only for authentication purposes, but also so as to correlate the spectral data with the content of fatty acids, which are important nutritional factors. A micro-optic sensor for the detection of olive oil aroma that is capable of distinguishing different ageing levels of extra virgin olive oil is also presented. It shows effective potential for acting as a smart cap of bottled olive oil in order to achieve a nondestructive olfactory perception of oil ageing. Lastly, a compact portable fluorometer for the rapid monitoring of the carcinogenic M1 aflatoxin in milk, is experimented. [ABSTRACT FROM PUBLISHER]

Dysplasia of the fibrous sheath (DFS) is an anomaly found in spermatozoa of severe asthenozoospermic patients. Marked hypertrophy and hyperplasia of the fibrous sheath is the common characteristic. Immunocytochemistry allowed us to visualize the distortions and incidence of tail structure abnormalities associated with this phenotype in six patients; four with a complete form and two with an incomplete form of this pathology previously diagnosed and studied by electron microscopy. Microtubules and fibrous sheaths were studied using monoclonal antibodies against alpha-acetylated tubulin and anti-FSC1 (the major protein component of the fibrous sheath). Mitochondrial sheaths were visualized using the mitochondrion-specific vital dye MitoTracker green FM(TM). Phase contrast and fluorescent microscopy of semen samples showed large numbers of spermatozoa with short, rigid, thick and irregular tails. As expected, anomalous and completely distorted fibrous sheaths, severe alterations of the axonemal microtubules and different patterns of mitochondrial sheath configurations were found. While ultrastructural studies of thin sections allow an in-depth knowledge of the internal organization of the sperm tail, fluorescence labelling of selected sperm components affords a unique view of the whole flagellum including topographical relationships of various organelles. The combination of these different approaches is essential for a comprehensive understanding of this particular pathology. [ABSTRACT FROM AUTHOR]