Metodi molecolari per la rilevazione di microrganismi negli alimenti e nell'ambiente

It has long been known that the classical methods are not sufficient for this purpose, in fact, although various isolation and enrichment media have been studied for growing microorganisms involved in different metabolic pathways, only a fraction of these can be cultivated in the laboratory and analysis times are often long and tedious. The purpose of this thesis was to develop molecular techniques for detection of well characterized bacterial species, as well as methods for studying microbial communities in complex environments, assessing the effectiveness and applicability of the methods. Two cases have been studied: †¢ Salmonella enterica and Campylobacter jejuni in chicken meat; †¢ the consistency and diversity of microbial community in the sediment of an eutrophic river system, in the presence, or absence of the rooted macrophyte Vallisneria spiralis. Salmonella enterica and Campylobacter jejuni are microorganisms contaminating the poultry meat, that can cause food-borne infections to humans, which may come into contact by ingestion of contaminated material. EFSA (European Food Safety Authority) has intensified in recent years, studies and publications related to these pathogens, controlling the occurrence of zoonoses and trying to develop systems for the implementation of diagnostic tools to monitor their presence in food. By following these guidelines, in the first phase of the thesis two methods, based on qualitative and quantitative Real Time PCR (qPCR), have been developed and tested to identify and quantify S. enterica and C. jejuni in pure cultures an