RESUMEN
A new antibacterial film was constructed to combat the severe spoilage of fruits and vegetables caused by microorganisms. Specifically, photoresponsive cinnamaldehyde-tanniciron acetate nanospheres (CTF NPs) were prepared using ultrasonic-triggered irreversible equilibrium self-assembly and ionic cross-linking co-driven processes and were integrated into the matrix of κ-carrageenan (KC) (CTF-KC films) as functional fillers. The CTF0.4-KC film (KC film doped with 0.4 mg/mL CTF NPs) showed a 99.99% bactericidal rate against both E. coli and S. aureus, extended the storage period of cherry tomatoes from 20 to 32 days. The introduction of CTF enhanced the barrier, thermal stability, and mechanical strength properties, albeit with a slight compromise on transparency. Furthermore, the biosafety of the CTF0.4-KC film was confirmed through hemolysis and cytotoxicity tests. Together, the aforementioned results demonstrated the outstanding antibacterial and fresh-keeping properties of CTF0.4-KC. These desirable properties highlight the potential use of CTF0.4-KC films in food preservation applications.
Asunto(s)
Antibacterianos , Escherichia coli , Conservación de Alimentos , Staphylococcus aureus , Escherichia coli/efectos de los fármacos , Conservación de Alimentos/instrumentación , Conservación de Alimentos/métodos , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Embalaje de Alimentos/instrumentación , Carragenina/química , Carragenina/farmacología , Solanum lycopersicum/química , Solanum lycopersicum/microbiología , Humanos , Acroleína/análogos & derivados , Acroleína/química , Acroleína/farmacología , Frutas/químicaRESUMEN
In this study, we proposed an innovative application of porcine immunoglobulin G (IgG)-functionalized Fe3O4 (IgG-Fe3O4) specifically designed to target and capture Staphylococcus aureus (S. aureus). In addition, aminophenylboronic acid-modified tetraphenylethylene nanoparticles (APBA-TPE NPs) were utilized, establishing a sandwich-type dual recognition system via interactions with the bacteria's extracellular glycolipids. This approach enables highly sensitive and precise detection of bacterial presence, with a limit of detection (LOD) reaching down to 5.0 CFU/mL. Specifically, the prepared APBA-TPE NPs achieved 99.99% bacterial inactivation within 60 min at a concentration of 200 µg/mL. The results showed that APBA-TPE NPs possess a remarkable capacity for reactive oxygen species (ROS) production, which could attack the bacterial cell membrane, leading to bacterial lysis and content leakage, and ultimately to bacterial death. Furthermore, the material still showed good recoveries ranging from 88.5% to 93.5% in actual water samples, as well as a favorable sterilizing effect of killing all microorganisms for 60 min. This research provides new strategies and insights into the construction of methods for the specific capture, detection, and inactivation of S. aureus.
Asunto(s)
Ácidos Borónicos , Nanopartículas del Metal , Nanopartículas , Infecciones Estafilocócicas , Animales , Porcinos , Staphylococcus aureus , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Bacterias , Inmunoglobulina GRESUMEN
New antibacterial agents are needed to overcome the challenges of microbial food contamination. In this study, we investigated the potential of Elaeagnus mollis polysaccharide (EMP) to modify black phosphorus (BP) for use as a bactericide for foodborne pathogenic bacteria. The resulting compound (EMP-BP) displayed enhanced stability and activity compared with BP. EMP-BP exhibited an increased antibacterial activity (bactericidal efficiency of 99.999 % after 60 min of light exposure) compared to EMP and BP. Further studies revealed that photocatalytically generated reactive oxygen species (ROS) and active polysaccharides acted collectively on the cell membrane, leading to cell deformation and death. Furthermore, EMP-BP inhibited biofilm formation and reduced expression of virulence factors of Staphylococcus aureus, and material hemolysis and cytotoxicity tests prove that the material had good biocompatibility. In addition, bacteria treated with EMP-BP remained highly sensitive to antibiotics and did not develop significant resistance. In summary, we report an environmentally friendly method for controlling pathogenic foodborne bacteria that is efficient and apparently safe.