Raspberry Ketone-Mediated Inhibition of Biofilm Formation in Typhimurium-An Assessment of the Mechanisms of Action.

is an important foodborne pathogen that causes gastroenteritis and systemic infection in humans and livestock. biofilms consist of two major components-amyloid curli and cellulose-which contribute to the prolonged persistence of inside the host. Effective agents for inhibiting the formation of biofilms are urgently needed. We investigated the antibiofilm effect of Raspberry Ketone (RK) and its mechanism of action against Typhimurium 14028 using the Congo red agar method, Calcofluor staining, crystal violet method, pellicle assay, and the TMT-labeled quantitative proteomic approach. RK suppressed the formation of different types of biofilms, including pellicle formation, even at low concentrations (200 µg/mL). Furthermore, at higher concentrations (2 mg/mL), RK exhibited bacteriostatic effects. RK repressed cellulose deposition in biofilm through an unknown mechanism. Swimming and swarming motility analyses demonstrated reduced motility in RK-treated typhimurium. Proteomics analysis revealed that pathways involved in amyloid curli production, bacterial invasion, flagellar motility, arginine biosynthesis, and carbohydrate metabolism, were targeted by RK to facilitate biofilm inhibition. Consistent with the proteomics data, the expressions of and genes were strongly down-regulated in RK-treated typhimurium. These findings clearly demonstrated the biofilm inhibition capability of RK, justifying its further study for its efficacy assessment in clinical and industrial settings.