Inactivation of extraintestinal pathogenic E. coli clinical and food isolates suspended in ground chicken meat by gamma radiation

Authors: XU, AIXIA - Oak Ridge Institute For Science And Education (ORISE); Scullen, Butch - Butch; Sheen, Shiowshuh - Allen; JOHNSON, JAMES - Department Of Veterans Affairs; Sommers, Christopher

Submitted to: Food Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/5/2019
Publication Date: 7/17/2019
Citation: Xu, A., Scullen, O.J., Sheen, S., Johnson, J., Sommers, C.H. 2019. Inactivation of extraintestinal pathogenic E. coli clinical and food isolates suspended in ground chicken meat by gamma radiation. Food Microbiology. https://doi.org/10.1016/j.fm.2019.103264.
DOI: https://doi.org/10.1016/j.fm.2019.103264

Interpretive Summary: Extraintestinal pathogenic Escherichia coli are common contaminants in poultry meat and have been implicated as causing inflammatory bowel disease (IBD), sepsis, and urinary tract infections (UTI) which affect millions of people each year at an economic cost > $25 billion. Ionizing (gamma)radiation is a US Food and Drug Administration approved and commercialized technology which can kill pathogenic bacteria in foods. In this study we determined the radiation resistance (D10-value), the radiation dose needed to kill 90% of ExPEC, in foods. The D10-value for twenty-five individual ExPEC suspended in ground chicken meat ranged from 0.18 to 0.61 kGy, with an average of 0.30 kGy, meaning they can easily be killed in poultry meat. Irradiated poultry meat will lower the risk of infectious disease for persons with IBD, sepsis, or recurrent UTI.

Technical Abstract: Extraintestinal pathogenic Escherichia coli are common contaminants in retail poultry and involved inflammatory bowel disease, urinary tract infections and meningitis in both animals and humans. They cause significantly more illnesses and deaths in humans than Shiga toxin-producing E. coli (STEC). Ionizing radiation is used commercially for improving the safety and shelf-life of foods. In this study we inoculated ground chicken meat with 25 individual isolates of clinical uropathogenic E. coli (UPEC) and newborn meningitis causing E. coli (NMEC), isolates from retail chicken meat (CM), as well as retail chicken-skin isolates identified in our laboratory (CS). We then determined their gamma radiation inactivation kinetics (D10-value). The mean D10-value for all isolates (n=25) was 0.30 kGy. The mean D10-value for the UPEC, NMEC, CM, and CS isolates were 0.25, 0.29, 0.29, and 0.39 kGy, respectively. The mean D10-value for the clinical isolates was 0.27 kGy vs. 0.34 kGy for the non-clinical isolates. ExPEC were similar to that of STEC which were previously evaluated in our laboratory. The radiation doses needed to kill STEC poultry meat should also kill ExPEC.