Synergistic antibacterial effects of non-volatile and volatile antibacterial substances from Litsea cubeba fruit and their application in pork preservation

Litsea cubeba fruit exhibits excellent antibacterial properties. However, existing research has largely overlooked its non-volatile antibacterial compounds. This study aimed to identify the primary non-volatile antibacterial compounds in Litsea cubeba fruit and analyze their synergistic antibacterial effects with volatile antibacterial components. The results revealed that lauric acid (LA) is the principal non-volatile antibacterial compound in Litsea cubeba fruit. Notably, LA and citral demonstrated a synergistic antibacterial effect against foodborne pathogens. The synergistic treatment of LA and citral damaged the cell wall and membrane of Listeria monocytogenes , causing cell deformation, plasmolysis, disrupted membrane potential, and reactive oxygen species accumulation. Furthermore, this synergistic interaction inhibited cellular energy metabolism, significantly reducing intracellular ATP levels and ATPase activity, as well as disrupting multiple metabolic pathways. In addition, LA synergistic citral effectively inhibited L. monocytogenes growth in pork stored at 4 °C while maintaining meat color and pH value stability. This study provides valuable insights for the development of antibacterial substances in Litsea cubeba fruit and their potential applications in food preservation. • The primary nonvolatile antibacterial substance in Litsea cubeba fruit is lauric acid. • The combination of lauric acid and citral exerts a synergistic antibacterial effect. • Synergism LA + citral disrupts cellular integrity in L. monocytogenes . • Synergism LA + citral inhibits multiple metabolic pathways in L. monocytogenes . • Synergism LA + citral can be effectively applied in pork preservation.