Skip to main content
ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Environmental Microbial & Food Safety Laboratory » Research » Publications at this Location » Publication #381936
Research Project: Characterization and Mitigation of Bacterial Pathogens in the Fresh Produce Production and Processing Continuum

Location: Environmental Microbial & Food Safety Laboratory

Title: Effects of hydrodynamic shear stress and equipment surface on Escherichia coli O157:H7 single- and multi-species biofilm formation

Author
item PRABHUKOT, GRISHMA - University Of Maryland School Of Medicine
item YIN, HSINBAI - US Department Of Agriculture (USDA)
item EGGLETON, CHARLES - University Of Maryland School Of Medicine
item Patel, Jitu

Submitted to: International Association for Food Protection Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 3/26/2021
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Introduction: Bacterial Pathogens can form biofilm on food contact surfaces and subsequently contaminate food during processing. Non-pathogenic bacteria promote stronger biofilm formation of bacterial pathogens in multi-species biofilms. Purpose: The aim of this study was to evaluate the single and multi-species biofilm formation of E. coli O157:H7 on different equipment surfaces at various hydrodynamic shear stresses. Methods: Biofilms were grown on stainless steel (SS), PTFE and polycarbonate (PC) coupons at shear stresses of 0.013, 0.043 and 0.088 N/m2 in a CDC bioreactor containing 10% trypticase soy broth that had been inoculated with E. coli O157:H7 alone or in combination with R. insidiosa for 48 h. Bacterial populations in E. coli O157:H7 and R. insidiosa biofilms from surface coupons were removed by scrapping and determined by spiral plating on MacConkey agar with sorbitol and Tryptic soy agar, respectively. Results: E. coli O157:H7 recovered from multi-species biofilms on PTFE (7.49 log CFU/cm2) were significantly higher than SS (6.59 log CFU/cm2). Overall, E. coli populations recovered from surfaces at 0.013 N/m2 shear stress (6.55 log CFU/cm2) were significantly lower than E. coli recovered at 0.043 N/m2 and 0.088 N/m2 (7.14 and 7.39 log CFU/cm2, respectively). R. insidiosa populations in multispecies biofilms at all the shear stresses were lower on SS surface compared to PTFE and PC surfaces. E. coli O157:H7 recovered in multi-species biofilms at 0.013 N/m2 shear stress (6.55 log CFU/cm2) were significantly higher than the E. coli O157:H7 in single species biofilms (4.75 log CFU/cm2). Similar trend of higher E. coli O157:H7 populations in multi-species biofilms was also observed at 0.043 N/m2 and 0.088 N/m2 shear stress. Significance: Higher E. coli O157:H7 populations in multi-species biofilms may require additional interventions to remove pathogens from equipment surfaces. Lower shear stress and stainless steel surface will help in controlling bacterial biofilm formation.