Fecha de publicación: -- Fuente: PubMed "essential oil" Int J Food Microbiol. 2026 Aug 27;462:112031. doi: 10.1016/j.ijfoodmicro.2026.112031. Online ahead of print.ABSTRACTProteus mirabilis, a "superbug" with notable environmental resilience and pathogenicity, is increasingly entering the food chain via contaminated food products. Perillaldehyde, the principal bioactive component of Perilla frutescens essential oil, has reported antimicrobial activity, but its mechanisms against P. mirabilis and its efficacy for salmon preservation are unclear. In this study, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of perillaldehyde were determined. Its antibacterial mechanism was investigated using membrane integrity assays, untargeted metabolomics, and analyses of biofilm-related phenotypes and gene expression. Its preservation efficacy was subsequently evaluated in salmon cold-storage model. The results showed that perillaldehyde inhibited P. mirabilis growth in a concentration- and time-dependent manner, resulting in complete eradication within 2 h at the minimum inhibitory concentration. It disrupted the bacterial cell membrane, causing surface poration and leakage of intracellular contents. Treatment also lowered intracellular pH and induced membrane depolarization, consistent with disruption of transmembrane ion gradients and impairment of cellular energy metabolism. Untargeted metabolomics revealed significant alterations in the bacterial intracellular metabolome, highlighted by the enrichment of steroid degradation and α-linolenic acid metabolism. Additionally, key energy-producing pathways, such as glycolysis/gluconeogenesis and oxidative phosphorylation, were significantly disrupted. Perillaldehyde also inhibited biofilm formation, decreased swimming motility, and disrupted quorum sensing, as evidenced by downregulation of the biofilm-related genes hisG, rcsD, rpoN, flhD, and luxS. In salmon preservation assays, perillaldehyde significantly reduced populations of P. mirabilis inoculated onto salmon surfaces. It also suppressed increases in total volatile basic nitrogen and total viable counts during nine days of storage at 4 °C, while maintaining color, texture, and overall sensory quality. Together, these results indicate that perillaldehyde exerts multi-target antibacterial effects and demonstrates promising potential as a natural preservative for refrigerated seafood.PMID:42700688 | DOI:10.1016/j.ijfoodmicro.2026.112031