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Abstract: Verocytotoxin-producing Escherichia coli (VTEC) are foodborne pathogens that cause outbreaks linked to consumption of meat and raw milk. In this note the authors report results obtained from a survey conducted on minced beef and raw bovine milk samples using a Multiplex PCR (M-PCR) for the detection of eae, stx 1, stx 2 and hlyA genes as a screening step followed by a colony blot hybridization (CBH) technique for the isolation of the VTEC. Of 100 minced beef and 123 raw milk samples, 13 (13%) and 7 (5.7%) were positive in the M-PCR and among these 9 and 3 strains were isolated using CBH, respectively. All isolates showed the presence of the stx 2 gene, single or in association with the other investigated genes. None of the isolates belonged to the O157, O26, O91, O103, O111 and O145 serogroups. The study showed that the use of M-PCR for the screening of samples coupled with a sensitive and specific detection technique, could improve the possibility of detection of VTEC strains in foods. Moreover, the presence of VTEC in minced beef and in raw milk confirms their important role as putative vehicles of infection to humans. Stringent control of these foodstuffs is essential for food safety purposes. [Copyright &y& Elsevier]

The need of accurate and reliable methods for DNA isolation and plant species identification in foodstuffs is of great importance, especially in the protection of high added value products. Fresh foods, which are not subjected to any modifications, are suitable for many kind of analysis; for processed products, such as musts, wines, olive oils, and pasta, the situation may be more complicated due to DNA fragmentation and, in the worst case, by its degradation. This work aimed to establish an exhaustive and reproducible analytical procedure for table grape DNA tracing in industrial musts. Three different DNA extraction methods were initially compared and DNA was tested in PCR for its suitability for the amplification reaction of microsatellite markers or simple sequence repeats (SSRs). An optimized DNA extraction method for microsatellite amplification was developed and adapted for industrial musts. Two SSR-based molecular methods, High Resolution Melting and capillary electrophoresis, were tested and the markers VrZAG62 and VrZAG79 were found to be the most informative. High Resolution Melting analysis, here applied for the first time on musts, proved to be the method of choice for a preliminary screening using four cultivars chosen as references and different DNA mixtures prepared in laboratory. Capillary electrophoresis, providing allele size, allowed a fine genotyping of musts in comparison with reference cultivars. The LOD 6 of a single grape cultivar in mixture with other varieties was also determined at 2.5 ng. Merging the information of the two molecular analyses applied to real samples, we demonstrated that is possible to discover case of musts adulterated with table grapes, and we propose our procedure in controlling musts quality and origin certification. [ABSTRACT FROM AUTHOR]