Antunes, Patrícia

Bar, N.

Borda, D.

Bucur, F.

Nicolau, A.

Novais, C.

Peixe, L.

Ribeiro, T.G.

English

Repositório Aberto da Universidade do Porto

7-11 July 2019 | Glasgow, Scotland | www.fems2019.org8th Congress of European MicrobiologistsABSTRACT BOOKIn collaboration with TABLE OF CONTENT  Oral presentations  (O001 – O302)…………….………………..……………..1 Poster Presentations (PM001 – PW498)………………………….……..301 Monday (PM001 – PM408)……….………….………….……….301  Tuesday (PT001 – PT412)………………..………………………..714 Wednesday (PW001- PW498)………………………………...1131         1502  PW366 Multiple molecular components of Listeria monocytogenes affected by high pressure processing treatments: Fourier transform-infrared spectroscopy insights  Teresa Goncalves Ribeiro1, Florentina Bucur2, Daniela Borda2, Carla Novais1, Patrícia Antunes1;3, Anca Nicolau2, Nadav Bar4, Luísa Peixe1  1UCIBIO/REQUIMTE. Faculty of Pharmacy, University of Porto, Porto, Portugal 2Dunarea de Jos University of Galati, Galati, Romania 3Faculty of Nutrition and Food Sciences, Porto, Portugal 4Norwegian University of Science and Techology, Norway   Background: High pressure processing (HPP) is an attractive alternative technology to conventional thermal treatments for inactivation of foodborne pathogenic bacteria. Despite its interest, the effect of HPP on bacterial cellular components is not well established, undermining the development of strategies for circumventing the emergence of HPP-tolerant bacteria.  Objectives: To evaluate the impact of different HPP treatments on molecular components of Listeria monocytogenes. Methods: Fourier-transform infrared with attenuated total reflectance (FTIR-ATR) spectra of two clinically-relevant L. monocytogenes strains (RO15-serotype 4b/herring+spices/Romania/2013; ScottA-1/2a/milk/France/1992) were acquired from stationary phase growth suspension cells, exposed to HPP treatments (300MPa-2/8/15’; 400MPa-2/8/15’; 600MPa-15’) or not, using Nicolet iS50 FT-IR spectrometer (6 replicates/resolution of 4cm-1/32 scan co-additions), and modeled with hierarchical cluster analysis (HCA) and partial least squares discriminant analysis (PLSDA).  Results: Strain specific spectra were observed before and after HPP treatments by HCA. L. monocytogenes cells submitted to HPP were clearly discriminated from non-treated cells by PLSDA, with variances occurring in all spectra. Three clusters were evidenced for each strain by HCA, corresponding to cells exposed to 300MPa-2’, 400MPa-2’ or 600MPa-15’. Additionally, all but two (RO15: 300MPa-8/15’, ScottA: 400MPa-8/15’) HPP treatments were discriminated by PLSDA, with multiple cell components being affected. Nevertheless, the main spectral variances were observed in proteins/amides I and II (1700-1500cm-1) and in phospholipids/DNA/RNA (1500-1200cm-1) regions, which seems to be the main targets of HPP. Elucidations of these cellular components are crucial for enhancing HPP efficacy (e.g. development of specific HPP additives) and for studying bacterial HPP tolerance responses.     

Multiple molecular components of Listeria monocytogenes affected by high pressure processing treatments: Fourier transform-infrared spectroscopy insights

https://repositorio-aberto.up.pt/bitstream/10216/125015/2/372194.pdf

Multiple molecular components of Listeria monocytogenes affected by high pressure processing treatments: Fourier transform-infrared spectroscopy insights

Abstract

Similar works

Full text

Available Versions

Repositório Aberto da Universidade do Porto