Action mechanisms of natural antimicrobials against food-borne pathogenes

Braschi, Giacomo (2018) Action mechanisms of natural antimicrobials against food-borne pathogenes, [Dissertation thesis], Alma Mater Studiorum Università di Bologna. Dottorato di ricerca in Scienze e tecnologie agrarie, ambientali e alimentari, 30 Ciclo. DOI 10.6092/unibo/amsdottorato/8479.
Documenti full-text disponibili:
Documento PDF (English) - Richiede un lettore di PDF come Xpdf o Adobe Acrobat Reader
Disponibile con Licenza: Creative Commons Attribution Non-commercial No Derivatives 3.0 (CC BY-NC-ND 3.0) .
Download (7MB) | Anteprima


Essential oils (EOs) or their components represent one of the most promising natural feasible alternatives to improve food safety, shelf-life and quality. Although their antimicrobial properties are well documented few and fragmented are the information about their mechanisms of action, cellular targets and on the stress response strategies of microorganisms after the exposure to such compounds. In this framework, the main aim of the PhD project was to investigate on the effects of one hour exposure to sublethal concentrations of selected natural antimicrobials, such as citral, carvacrol, (E)-2-hexenal and thyme EO, on the food-borne pathogens Listeria monocytogenes Scott A and Escherichia coli K12 MG1655. The action mechanisms of the natural antimicrobials and the cellular targets were studied through multiple approaches able to give information on cell morphological, physiological, transcriptome and proteome changes. The results obtained allowed to define for each strain and each antimicrobial the cell targets and the response mechanism, respectively. The use of the different multi-parametric approaches provided useful information on citral, carvacrol, (E)-2-hexenal and thyme EO action mechanisms on microbial cell targets as well as to elucidate the behavior and the stress response strategies used by Listeria monocytogenes Scott A and Escherichia coli K12 MG1655 after the one hour exposure to such natural antimicrobials. The validation in apple juice allowed to understand the real potential of one of the antimicrobials (chosen on the basis of its sensory compatibility with the food matrix) to improve food safety and shelf life. The data obtained can speed up the exploitation at industrial level of natural antimicrobials as alternative food preservatives.

Tipologia del documento
Tesi di dottorato
Braschi, Giacomo
Dottorato di ricerca
Settore disciplinare
Settore concorsuale
Parole chiave
Natural antimicrobials, Listeria monocytogenes, Escherichia coli, stress response, food safety
Data di discussione
4 Maggio 2018

Altri metadati

Statistica sui download

Gestione del documento: Visualizza la tesi