The antibacterial activity of plantaricin GZ1–27 against MRSA and its bio-preservative effect on chilled pork in combination with chitosan

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) poses great threats to human health. In this research, we found that the newly discovered bacteriocin plantaricin GZ1–27 could efficiently inhibit the MRSA, with a MIC of 32 μg/mL. Comprehensive investigations were carried out by analysis of K+ leakage, propidium iodide assay, and cell ultra-structure analysis with scanning electron microscopy and transmission electron microscopy. The results consistently showed that plantaricin GZ1–27 could increase the permeability of the membrane and impair its integrity, which induced the collapse of the cell structure and thus led to cell death. Furthermore, by sensory evaluation and biochemical analysis, it was found that plantaricin GZ1–27 combined with chitosan could significantly improve the preservation of pork when applied to the surface of meat slices. Overall, our research clearly showed the anti-MRSA bactericidal mechanism of plantaricin GZ1–27, which, together with its preliminary application trials in pork, suggested plantaricin GZ1–27 could be a potential anti-MRSA agent and is promising to be applied in pork preservation to extend the shelf life.