Antibacterial mechanism of hops β-acids against methicillin-resistant

Introduction: Skin wounds infected by Methicillin-resistant staphylococcus aureus (MRSA) still remain an important clinical challenge. β-acids, secondary metabolites extracted from hops, exhibit a powerful antibacterial effect on MRSA. Methods: In this study, the antimicrobial activity of β-acids against MRSA and the corresponding mechanism were studied. Results: The antimicrobial activity results revealed that β-acids was sensitive to MRSA (MIC = 62.5 μg/mL and MBC = 250 μg/mL). After β-acids treatment, the morphological changes of MRSA, including surface roughness, cellular crumpling, and fracture. The content of extracellular macromolecules, such as nucleic acids and proteins, increased significantly when β-acids treatment was applied, indicating that the integrity and permeability of cell membranes were disrupted. Meanwhile, laser confocal microscopy results showed that the cell membrane was severely damaged. Additionally, β-acids minimized intracellular adenosine triphosphate (ATP), suppressed Na Discussion: Overall, β-acids may be promising agents for the effective treatment of MRSA.