An In Vitro Study of the Effect of Extracts on Key Processes in the Development of Staphylococcal Infections.

is still one of the leading causes of both hospital- and community-acquired infections. Due to the very high percentage of drug-resistant strains, the participation of drug-tolerant biofilms in pathological changes, and thus the limited number of effective antibiotics, there is an urgent need to search for alternative methods of prevention or treatment for infections. In the present study, biochemically characterized (HPLC/UPLC-QTOF-MS) acetonic, ethanolic, and water extracts from fruits and bark of L. were tested in vitro as diet additives that potentially prevent staphylococcal infections. The impacts of extracts on sortase A (SrtA) activity (Fluorimetric Assay), staphylococcal protein A (SpA) expression (FITC-labelled specific antibodies), the lipid composition of bacterial cell membranes (LC-MS/MS, GC/MS), and biofilm formation (LIVE/DEAD BacLight) were assessed. The cytotoxicity of extracts to the human fibroblast line HFF-1 was also tested (MTT reduction). extracts strongly inhibited SrtA activity and SpA expression, caused modifications of cell membrane, limited biofilm formation by staphylococci, and were non-cytotoxic. Therefore, they have pro-health potential. Nevertheless, their usefulness as diet supplements that are beneficial for the prevention of staphylococcal infections should be confirmed in animal models in the future.