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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Environmental Microbial & Food Safety Laboratory » Research » Publications at this Location » Publication #397761
Research Project: Intervention Strategies to Mitigate the Food Safety Risks Associated with the Fresh Produce Supply Chain

Location: Environmental Microbial & Food Safety Laboratory

Title: Effect of surface topography and shear stress on biofilm formation by Listeria monocytogenes in presence of promotor bacteria

Author
item PRABHUKHOT, GRISHMA - University Of Maryland School Of Medicine
item Yin, Hsin Bai
item EGGELTON, CHARLES - University Of Maryland School Of Medicine
item Patel, Jitu

Submitted to: Proceedings of the International Conference on Gram-positive Microorganisms
Publication Type: Abstract Only
Publication Acceptance Date: 9/7/2022
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Pathogens can form biofilm on equipment surfaces and contaminate foods during processing. Promotor bacteria Ralstonia insidiosa may facilitate stronger biofilm formation of pathogens. Effects of hydrodynamic shear stresses and abiotic surface topography on single and dual species biofilm formation of L. monocytogenes was investigated. CDC bioreactor was inoculated with L. monocytogenes alone or with R. insidiosa for 48 h to grow biofilms on stainless steel (SS), PTFE, polycarbonate (PC) and EPDM coupons. L. monocytogenes and R. insidiosa populations in biofilms from surface coupons (n=144) were determined by spiral plating on MOX and TSA, respectively. The log CFU/cm2 from three individual replicates were analyzed. L. monocytogenes recovered from dual-species biofilms from SS, PTFE and PC surfaces were statistically higher (p < 0.05) at the lowest shear stress of 0.013 N/m2 compared to 0.043 and 0.088 N/m2. At the highest shear stress of 0.088 N/m2, L. monocytogenes populations recovered from dual-species biofilms were higher (p < 0.05) on PTFE (8.17 log CFU/cm2) and EPDM (7.93 log CFU/cm2) compared to SS 316L (7.38 log CFU/cm2) and PC (7.57 log CFU/cm2). L. monocytogenes recovered from dual-species environment were significantly higher than single-species biofilms under all shear stresses. PTFE and PC surface had higher surface roughness (3.17 and 2.36 µm, respectively) compared to EPDM (1.11 µm) and SS 316L (0.71 µm). Surface topography and shear stress both, impact L. monocytogenes biofilm formation in a dual species environment. R. insidiosa promotes L. monocytogenes biofilm formation on all materials and under all shear stresses.