Exploring Oak-Derived Phenolics to Control Quorum Sensing and Lipase-Mediated Spoilage in Pseudomonas fluorescens

Pseudomonas fluorescens is a major psychrotrophic bacterium responsible for spoilage in refrigerated foods, particularly dairy products, where deterioration is driven by biofilm formation, quorum sensing (QS) regulation, and the secretion of thermostable lipases. Conventional control strategies reduce bacterial loads but often fail to prevent enzymatic spoilage. Plant-derived phenolic compounds have been widely reported as QS inhibitors and lipase modulators in various biological systems; however, evidence specifically addressing their effects on P. fluorescens regulatory networks and bacterial lipases remains limited. This review critically examines current knowledge on QS-mediated biofilm formation and lipase production in P. fluorescens and analyzes the reported inhibitory activity of phenolic compounds, with emphasis on oak (Quercus spp.)-derived metabolites. While flavonoids and phenolic acids such as quercetin, gallic acid, and p-coumaric acid have demonstrated QS inhibition and antilipolytic activity in other Pseudomonas species and pancreatic models, direct mechanistic validation in P. fluorescens lipases is scarce. Moreover, most studies rely on crude plant extracts without comprehensive metabolomic characterization, and the potential contribution of additional oak metabolites, including terpenoids, remains largely unexplored. Identifying these gaps is essential for advancing toward integrative approaches that combine enzymology, molecular modeling, and validation in food-relevant systems.