Work

Survival of Escherichia coli O157:H7 and Listeria monocytogenes on Spinach and Blueberries Treated With Aqueous Chlorine Dioxide and Muscadine (Vitis rotundifolia) Extract

Year: 2025

Type: article

Abstract: The antimicrobial effect of various concentrations of chlorine dioxide (ClO 2 ) and muscadine extract (ME) were investigated on Escherichia coli O157:H7 and Listeria monocytogenes under in vitro conditions and on treated spinach and blueberries. Tryptic soy broth (TSB) and produce were inoculated with a 3-strain cocktail of each pathogen. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using either 96-well plates incubated in a microplate reader for ClO 2 or test tubes incubated in a conventional incubator at 37°C for 24 h for the ME. Pathogen reduction on inoculated produce (inoculation levels were 5.6-7.0 log CFU/g for spinach and 4.5-5.1 log CFU/g for blueberries) was evaluated after exposure to various antimicrobial treatments for 10 min + 30-45 min dry time + storage at 8°C for up to six days. Under in vitro , L. monocytogenes was more susceptible than E. coli O157:H7 to ClO 2 and ME. On spinach, 300 mg/ml ME and 3 ppm ClO 2 + 300 mg/ml ME treatments resulted in the maximum reduction of E. coli O157:H7 (4.6 log CFU/g reduction at day 1) and L. monocytogenes (5.6 log CFU/g reduction at day 2), respectively. On blueberries, all the treatments significantly decreased E. coli O157:H7 counts (≤1.7 log CFU/g), and no differences (P>0.05) were detected from day 1 to 6. The treatment 3 ppm ClO 2 + 300 mg/ml ME led to non-detectable (P≤0.05) L. monocytogenes levels on blueberries at days 1, 2, 4, and 6, leading to surface reductions >4.1 log CFU/g. Based on the study, ME combined with ClO 2 could be a potential candidate as postharvest treatment to reduce the presence of E. coli O157:H7 and L. monocytogenes on blueberries. Both pathogens were less susceptible to these combined treatments on spinach.

Source: Journal of Food Protection

DOI: 10.1016/j.jfp.2025.100559

Authors: Angelica Abdallah, Juan L. Silva, Wes Schilling, Eric T. Stafne, Shecoya B. White

Institution: Mississippi State University

Language: English

Topic: Listeria monocytogenes in Food Safety

Subfield: Biotechnology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDGs: Good health and well-being, Zero hunger

Open Access status: gold

Estimated APC paid: $2,300