title: Discrimination of intact and injured Listeria monocytogenes by Fourier transform infrared spectroscopy and principal component analysis.
abstract: Fourier transform infrared spectroscopy (FT-IR, 4000-600 cm(-)(1)) was used to discriminate between intact and sonication-injured Listeria monocytogenes ATCC 19114 and to distinguish this strain from other selected Listeria strains (L. innocua ATCC 51742, L. innocua ATCC 33090, and L. monocytogenes ATCC 7644). FT-IR vibrational overtone and combination bands from mid-IR active components of intact and injured bacterial cells produced distinctive "fingerprints" at wavenumbers between 1500 and 800 cm(-)(1). Spectral data were analyzed by principal component analysis. Clear segregations of different intact and injured strains of Listeria were observed, suggesting that FT-IR can detect biochemical differences between intact and injured bacterial cells. This technique may provide a tool for the rapid assessment of cell viability and thereby the control of foodborne pathogens.
authors.affiliation: Department of Food Science and Human Nutrition, Box 646376, Washington State University, Pullman, Washington 99164-6373, USA. mengshi@mail.wsu.edu
authors.forename: Mengshi
authors.initials: M
authors.lastname: Lin
authors.forename: Murad
authors.initials: M
authors.lastname: Al-Holy
authors.forename: Hamzah
authors.initials: H
authors.lastname: Al-Qadiri
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kang
authors.forename: Anna G
authors.initials: AG
authors.lastname: Cavinato
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Huang
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Rasco
mesh_terms: D005506:Food Contamination / Q000517:prevention & control; D005516:Food Microbiology; D008089:Listeria monocytogenes / Q000737:chemistry* / Q000302:isolation & purification*; D013010:Sonication; D017550:Spectroscopy, Fourier Transform Infrared