0000000000560584
AUTHOR
Francesco Villani
Presence and characterisation of verotoxin producing E. coli in fresh Italian pork sausages, and preparation and use of an antibiotic-resistant strain for challenge studies
One hundred and twenty six samples of fresh pork sausages were analysed-for the presence of verocytotoxigenic Escherichia coli (VTEC). Selective enrichment followed by DNA extraction and PCR amplification of the stx1 and stx2 genes highlighted the occurrence of the above mentioned genes in 20 out of 126 samples screened. From the stx positive enriched cultures, isolation was performed on CT-SMAC agar plates after immuno-magnetic separation of E. coli O157. Fifty three non-sorbitol fermenting isolates were obtained and further characterised, along with the reference strain E. coli ATCC 35150(T). All the isolates were characterised by PCR assays, assessing the presence of stx1, stx2, rfbE(O15…
Heterotrophic microorganisms in deteriorated medieval wall paintings in southern Italian churches
The Campania region in southern Italy is noted for its large number of churches that harbour invaluable frescoes, dated from the beginnings of the 4th up to the 13th century. The wall paintings represent an integral part of the monuments, and their deterioration constitutes a potentially significant loss for the world's cultural heritage. Heterotrophic microorganisms such as bacteria and mould can grow on the surface of paintings that contain a wide range of organic and inorganic constituents, and provide different ecological. niches that are exploited by a large variety of microbial. species. We isolated and identified the heterotrophic microorganisms found in the biodegraded medieval wall…
Technological and molecular diversity of Lactobacillus plantarum strains isolated from naturally fermented sourdoughs.
Thirty Lactobacillus (L.) plantarum strains, isolated from sourdough, were identified by biochemical tests as well as 16S rDNA sequencing and differentiated on the basis of technological properties, such as amylase, protease, phytase and antirope activities. These properties were shown to be widely differing among the strains, indicating a significant technological diversity. Genetic differentiation was achieved by restriction endonuclease analysis-pulsed field gel electrophoresis (REA-PFGE) that allowed the L. plantarum strains to be divided into 10 different genomic groups. Moreover, 32 different starters were employed in dough making experiments; each starter consisted of a single strain…