RESUMO
Foodborne diseases caused by bacteria have aroused ongoing concerns for food safety. Most existing packaging plastics bring pollution and potential toxicity. Here antimicrobial dialdehyde cellophane (DACP) was developed by periodate oxidation. The structure, mechanical properties, optical properties, and barrier properties of DACP were characterized. The antimicrobial activity of DACP against four Gram-positive bacteria was studied. The packaging effect of DACP for food with high water content was evaluated, including strawberry and tofu. The antimicrobial activity of DACP improved with increased aldehyde content. Compared with the polyethylene film and cellophane, our DACP exhibited excellent antimicrobial effect and extended the shelf life of food significantly, which shows promising prospects in food packaging.
Assuntos
Antibacterianos/farmacologia , Celulose Oxidada/farmacologia , Embalagem de Alimentos , Bactérias Gram-Positivas/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Configuração de Carboidratos , Celulose Oxidada/síntese química , Celulose Oxidada/química , Testes de Sensibilidade MicrobianaRESUMO
Antibiotic abuse resulted in the emergence of multidrug-resistant Gram-positive pathogens, which pose a severe threat to public health. It is urgent to develop antibiotic substitutes to kill multidrug-resistant Gram-positive pathogens effectively. Herein, the antibacterial dialdehyde nanocrystalline cellulose (DNC) was prepared and characterized. The antibacterial activity and biosafety of DNC were studied. With the increasing content of aldehyde groups, DNC exhibited high antibacterial activity against Gram-positive pathogens in vitro. DNC3 significantly reduced the amounts of methicillin-resistant Staphylococcus aureus (MRSA) on the skin of infected mice models, which showed low cytotoxicity, excellent skin compatibility, and no acute oral toxicity. DNC exhibited potentials as antibiotic substitutes to fight against multidrug-resistant bacteria, such as ingredients in salves to treat skin infection and other on-skin applications.
Assuntos
Antibacterianos/uso terapêutico , Celulose/análogos & derivados , Nanopartículas/uso terapêutico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Linhagem Celular , Celulose/química , Celulose/uso terapêutico , Celulose/toxicidade , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Nanopartículas/química , Nanopartículas/toxicidade , Pele/efeitos dos fármacos , Pele/microbiologia , Pele/patologia , Infecções Cutâneas Estafilocócicas/patologiaRESUMO
Even though iron oxide (Fe3O4) nanoparticles are promising materials for magnetic resonance imaging (MRI) contrast agents, their biocompatibility and targeting efficacy still need to be improved. Herein, we modified glycyrrhetinic acid (GA) groups on Fe3O4 nanoparticles (Fe3O4@cGlu-GA) for liver tumor-targeted imaging. To evaluate the biocompatibility of these nanoparticles, we studied their cytotoxicity, hemolysis, and hepatotoxicity. We measured the uptake of Fe3O4@cGlu-GA nanoparticles in normal and liver tumor cells, then we investigated the specificity of Fe3O4@cGlu-GA nanoparticles in mouse models bearing subcutaneous and orthotopic liver tumors. With good biocompatibility and targeting efficacy both in vitro and in vivo, the Fe3O4@cGlu-GA nanoparticles are promising MRI contrast agents with ultralow hepatotoxicity and show great improvement on existing Fe3O4-based nanoparticles.
