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.
Keywords: MRSA; antibacterial activity; antibiotic substitutes; dialdehyde; nanocellulose; nanocrystalline cellulose.