Evaluation of quantitative recovery methods for Listeria monocytogenes applied to stainless steel.

J AOAC Int

Virginia Tech, Department of Food Science and Technology (0418), Blacksburg, VA 24061, USA.

Published: July 2007

The ability of Listeria monocytogenes to attach to various food contact surfaces, such as stainless steel, polypropylene, and rubber compounds, is well documented. The retention of these or other pathogenic bacteria on food contact surfaces increases the risk of transmission to food products. The objective of this study was to compare several methods for quantitative recovery of Listeria monocytogenes from stainless steel surfaces. A cocktail of 4 serotypes of Listeria monocytogenes mixed in equivalent concentrations was inoculated onto type 304 stainless steel coupons in a 2 x 2 cm area. After 1 h exposure, coupons were sampled by one of the following methods: (1) swabbing with a premoistened Dacron swab; (2) rinsing with phosphate-buffered saline; (3) direct contact onto tryptic soy agar containing 0.6% yeast extract (TSA + YE) plates for 10 s; (4) sonication in an ultrasonic water bath (40 kHz); (5) contact with the bristles of a sonicating brush head for 1 min; and (6) indirect contact (2-4 mm distance) with a sonicating brush head for 1 min. The 3 sonication methods yielded higher recovery than the other 3 methods (P < 0.05). Brushing the coupons with the sonicating brush head (contact or noncontact) yielded a recovery level of about 60%. The lowest cell recovery (about 20%) was observed with the swab and direct agar contact methods. After a 12 h exposure, recoveries ranged from 17.4 (brush contact method) to 2% (swab method).

Download full-text PDF

Source

Publication Analysis

Top Keywords

listeria monocytogenes
16
stainless steel
16
sonicating brush
12
brush head
12
quantitative recovery
8
recovery methods
8
contact
8
food contact
8
contact surfaces
8
head min
8

Similar Publications

Microbial safety of black soldier fly larvae (Hermetia illucens) reared on food waste streams.

Waste Manag

January 2025

Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, Queensland 4072, Australia; School of Agriculture and Food Sustainability, Faculty of Science, University of Queensland, Brisbane, Queensland 4072, Australia.

Black soldier fly larvae (BSFL) can valorise different organic matter and yield a product of high nutritional value. The lack of knowledge about the microbial safety of BSFL grown on different organic waste streams influences the commercialisation of BSFL as stockfeed ingredient. This study evaluates the microbial safety of BSFL grown on five different commercial food waste streams collected from two commercial production facilities.

View Article and Find Full Text PDF

Spent coffee grounds (SCGs) have been explored for use as various bioresources, such as biofuels, and are known to possess biological functions, including antioxidant activity. However, the antibiofilm properties of SCGs against pathogenic bacteria have not been fully investigated. Therefore, this study aimed to highlight the inhibitory effects of SCG extract (SCGE) on biofilm formation in Listeria monocytogenes and investigated the underlying mechanisms.

View Article and Find Full Text PDF

A Dual-Mode Colorimetric and Fluorescence Biosensor Based on a Nucleic Acid Multiplexing Platform for the Detection of .

Anal Chem

January 2025

Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin 300071, China.

() is one of the most prevalent threats, capable of inducing diverse illnesses and presenting a serious threat to public health. Herein, we demonstrate a novel dual-mode colorimetric/fluorescence biosensor based on the xponential mplification reaction and trand isplacement eactions (EASDR), which has multiplexing capability that significantly promotes the anchoring and trapping of Pt nanoparticles (Pt NPs) and fluorescent dyes for sensitive detection of (). The method works by targeting specific bacteria with aptamers and promoting repeated EASDR to affect the immobilization of Pt NPs and fluorescent dyes in the orifice plate, which could produce changes in fluorescence and colorimetric signals.

View Article and Find Full Text PDF

ERK activation waves coordinate mechanical cell competition leading to collective elimination via extrusion of bacterially infected cells.

Cell Rep

January 2025

Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, 72076 Tübingen, Baden-Württemberg, Germany; Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, 72076 Tübingen, Baden-Württemberg, Germany. Electronic address:

Epithelial cells respond to infection with the intracellular bacterial pathogen Listeria monocytogenes by altering their mechanics to promote collective infected cell extrusion (CICE) and limit infection spread across cell monolayers. However, the underlying biochemical pathways remain elusive. Here, using in vitro (epithelial monolayers) and in vivo (zebrafish larvae) models of infection with L.

View Article and Find Full Text PDF

Introduction: is a formidable pathogen that poses a significant threat to immunocompromised and might cause rare atypical forms of the disease especially complicated with coinfection.

Case: We present a case of a patient with meningoencephalitis, endocarditis, sepsis, and osteomyelitis, highlighting the complexities of managing disseminated polymicrobial infection. A 64-year-old female with multiple myeloma treated with chemotherapy presented with fever, altered mental status, nausea, and diarrhea to the emergency department.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!