Cinnamaldehyde nanoemulsion disrupts Listeria monocytogenes biofilms: Metabolomics reveals dual inhibition and removal mechanisms

To address the persistent colonization of Listeria monocytogenes (L. monocytogenes) biofilms on food processing surfaces, which poses critical food safety risks, this study investigated the multi-target antibiofilm mechanism of cinnamaldehyde nanoemulsion (CAN) based on its previously established efficacy. Results demonstrated that CAN compromised membrane integrity, increasing intracellular conductivity while facilitating protein and nucleic acid leakage. It concurrently suppressed adenosine triphosphate (ATP) synthesis and accelerated reactive oxygen species (ROS) accumulation, ultimately triggering ion imbalance and metabolic homeostasis collapse. Furthermore, CAN significantly reduced L. monocytogenes motility, enhanced surface hydrophobicity, and inhibited extracellular polymeric substance (EPS) secretion, thereby disrupting biofilm assembly. The sharp decline in viable biofilm cells critically impaired structural recovery. Metabolomics further revealed that CAN inhibited initial adhesion through targeted suppression of fatty acid metabolism and teichoic acid biosynthesis while disrupting biofilm maintenance and repair via interference with ABC transporter functionality and D-amino acid metabolism. This study elucidated the mechanism by which CAN inhibited and removed biofilms from a metabolomics perspective, providing novel insights for biofilm control strategies in the food industry.