Location: Environmental Microbial & Food Safety Laboratory
Title: Antibiofilm efficacy of Peptide 108 against listeria monocytogenes and shiga toxigenic Escherichia coli on equipment surfacesAuthor
BOOMER, ASHLEY - US Department Of Agriculture (USDA) | |
HSIN-BAI, YIN - University Of Maryland | |
Patel, Jitu |
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/3/2019 Publication Date: 11/1/2019 Citation: Boomer, A., Hsin-Bai, Y., Patel, J.R. 2019. Antibiofilm efficacy of Peptide 108 against listeria monocytogenes and shiga toxigenic Escherichia coli on equipment surfaces. Journal of Food Protection. https://doi.org/10.4315/0362-028X.JFP-19-168. DOI: https://doi.org/10.4315/0362-028X.JFP-19-168 Interpretive Summary: Bacterial pathogens can attach and colonize on equipment surfaces at the food processing facility. These disease-causing bacteria are difficult to remove by commonly used sanitizes such as chlorine once strongly attached and form biofilm on equipment surface. The current trend is to reduce use of chlorine during the disinfection process due to its impact on environment and occupational health. We investigated the effect of peptide 1018 for inactivating Listeria monocytogenes and Shiga-toxigenic Escherichia coli (STEC, O26, O111, O145, O157) biofilms on stainless steel and polycarbonate surfaces. The bacterial biofilms formed on these surfaces using CDC bioreactors were treated with peptide 1018 at 10 - 50 µg/ml concentrations for 24 h. Surviving bacterial populations were determined by scrapping off the coupons and spiral plating on selective media. Significantly higher bacterial populations were attached on polycarbonate surfaces than on stainless steel. Antibiofilm efficacy of peptide 1018 against pathogens was concentration-dependent and varied with the type of pathogen and material surfaces. Peptide 1018 concentrations at 50 µg/ml significantly inactivated all tested bacterial biofilms on both surfaces. L. monocytogenes was more sensitive to peptide 1018 compared to STEC on stainless steel surfaces. Result suggest that peptide 1018 may be used to inactivate L. monocytogenes and STEC biofilms on equipment surfaces. These benefits could benefit food processors seeking to reduce the risk of pathogen cross-contamination of food at the processing facility. Technical Abstract: Listeria monocytogenes and Shiga-toxigenic Escherichia coli (STEC) are important food-borne bacterial pathogens that can colonize and form biofilms on a wide range of equipment surfaces at the food processing facilities. Pathogens in biofilms are resistant to conventional antimicrobials and require higher antimicrobial concentrations to inactivate biofilms. In this study, we investigated the efficacy of a synthetic innate defense regulator peptide 1018 (peptide 1018) for inactivating L. monocytogenes and STEC (O26, O111, O145, O157) biofilms on stainless steel and polycarbonate surfaces. Stainless steel and polycarbonate coupons (12 mm diameter) were used in the CDC-biofilm reactor containing 400 ml of 10% trypticase soy broth (TSB) that had been inoculated with individual strain of L. monocytogenes or STEC to obtain 6 log CFU/ml populations. The reactor was set with a constant flow rate at 50 ml/h of 10% TSB for 48 h. After 48 h, coupons were treated with peptide 1018 at 0, 10, 20, or 50 µg/ml concentrations in phosphate buffer saline (PBS) for 24 h. Surviving bacterial populations were determined by scrapping off the coupons and spiral plating on selective media. Significantly higher levels of pathogens in biofilms were recovered on polycarbonate surfaces than on stainless steel. Antibiofilm efficacy of peptide 1018 against pathogens was concentration-dependent and varied with the type of pathogen and material surfaces. Peptide 1018 concentrations at 50 µg/ml significantly inactivated all tested bacterial biofilms on both surfaces as compared to the control (P < 0.05). L. monocytogenes was the most sensitive bacterium to peptide 1018, where 2-4 log CFU/cm2 reduction following treatment with 10-50 µg/ml peptide 1018 in Listeria populations was found as compared to 1-2.5 log CFU/cm2 reduction with STEC on stainless steel surfaces. Result suggest that peptide 1018 may be used to inactivate L. monocytogenes and STEC biofilms on equipment surfaces. |