Surface-dependent persistence and transfer of Listeria monocytogenes in multispecies biofilms on food-contact surfaces

Authors: FALCO, IRENE - Orise Fellow; YANG, YISHAN - Orise Fellow; Patel, Jitendra; Nou, Xiangwu

Submitted to: Biofilms
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/7/2026
Publication Date: 7/8/2026
Citation: Falco, I., Yang, Y., Patel, J.R., Nou, X. 2026. Surface-dependent persistence and transfer of Listeria monocytogenes in multispecies biofilms on food-contact surfaces. Biofilms. 12. Article e100381. https://doi.org/10.1016/j.bioflm.2026.100381.
DOI: https://doi.org/10.1016/j.bioflm.2026.100381

Interpretive Summary: Biofilm formation by foodborne pathogens on food contact surfaces can serve as sources of persistent microbial contamination and pose safety risks for food processing. In this study, ARS scientists evaluated the effects of native microbiota from a commercial fresh produce processing facility on Listeria monocytogenes biofilm formation and transfer potential on coupons representing commonly used food contact surfaces. It showed that mixing L. monocytogenes and the native microbiota in cultures greatly enhanced the production of multi-species biofilms on various food contact surfaces, which in turn led to larger or more persistent L. monocytogenes transfer to spinach leaves. Changes in biofilm cell hydrophobicity and biofilm organization could be major contributing factors for the altered transfer (contamination) patterns for multispecies biofilms. This information could help stakeholders in the fresh produce industry for designing more effective treatments against multispecies biofilms in the processing environments.

Technical Abstract: Listeria monocytogenes persistence in food processing environments is closely associated with biofilm formation on food-contact surfaces and subsequent transfer to fresh produce. However, the role of native environmental microbiota in shaping pathogen behaviour within biofilms remains poorly understood. This study evaluated biofilm formation, transfer dynamics, cell surface hydrophobicity, and biofilm organization of L. monocytogenes in mono- and multispecies biofilms on stainless-steel (SS), silicone rubber (SR), and polycarbonate (PC) surfaces under low-shear conditions. Multispecies biofilms enhanced L. monocytogenes persistence and modulated cross-contamination dynamics in a surface-dependent manner. On SS, multispecies biofilms showed reduced initial transfer but sustained cumulative transfer across sequential contacts compared to monospecies biofilms, indicating greater structural stability. In contrast, PC exhibited high initial transfer followed by rapid transfer plateauing, whereas SR supported limited accumulation after the first contact event. Higher cell surface hydrophobicity in multispecies biofilms, particularly on SS, was associated with increased biofilm cohesion. Together with fluorescence microscopy observations, these results suggest that biofilm organization, rather than total cell numbers alone, plays a key role in determining persistence and transfer behaviour. Overall, both surface properties and microbial community composition influence L. monocytogenes biofilm stability and cross-contamination risk. Incorporating surface-dependent and ecological factors into hygienic design and sanitation strategies may improve contamination control in fresh produce processing environments.