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Title: Decontamination of raw produce by surface microdischarge and the evaluation of its damage to cellular components
Abstract

The use of surface microdischarge (SMD) for the bacterial decontamination of raw produce was evaluated. With 1 min of SMD treatment, >2 logarithmic reduction inEscherichia coliO157:H7 was consistently observed. The scanning electron microscopy ofE. coliO157:H7 show that SMD damages the cell membrane, leads to cell expansion, and eventually lysis. The attenuated total reflectance‐Fourier‐transform infrared spectroscopy characterization ofE. coliO157:H7 and lipopolysaccharides (LPS) shows that SMD causes (a) the oxidation of cellular components by forming COOH and COOgroups inside and on the cell wall, and (b) the modification of polysaccharides and phosphorus‐containing groups found in phospholipids and DNA. Further characterization with X‐ray photoelectron spectroscopy suggests SMD mainly modifies the O‐chain and core‐polysaccharide part of LPS.

 
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NSF-PAR ID:
10088580
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Plasma Processes and Polymers
Volume:
16
Issue:
5
ISSN:
1612-8850
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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