Screening and identification of a bacteriocin-producing lactic acid bacterium and its antibacterial effect on Staphylococcus aureus

ObjectiveThis study aimed to isolate and screen bacteriocin-producing lactic acid bacteria from kimchi, identify the strains and investigate their antibacterial effects against Staphylococcus aureus.MethodsS. aureus was employed as the indicator bacterium. Bacteriocin-producing strains were identified through acid elimination, hydrogen peroxide exclusion, and enzyme verification test. Physiological and biochemical identification, along with 16S rDNA sequencing, was conducted on the strains. The antibacterial properties of the bacteriocin extract were assessed using minimum inhibitory concentration (MIC) determination, growth curve analysis, biofilm staining, and scanning electron microscopy observations.ResultsA bacteriocin-producing strain, designated N-11, was successfully isolated and identified as Lactobacillus plantarum. The MIC of the crude bacteriocin extract against S. aureus was found to be (17.50±0.25) mg/mL, demonstrating a significantly ability to inhibit both the growth and the biofilm formation of S. aureus.ConclusionThe crude extract producted by L. plantarum N-11 exhibits strong antibacterial effects against S. aureus, indicating its potential for further development and utilization in food preservation and safety applications.