Antibacterial electrospun chitosan-based nanofibers: A bacterial membrane perforator

Area of Science:

• Biomaterials Science
• Microbiology
• Food Science

Background:

• Bacterial membrane integrity is crucial for cell viability.
• Chitosan and its derivatives are explored for antimicrobial properties.
• Developing effective antibacterial agents for food preservation is a priority.

Purpose of the Study:

• To investigate the antibacterial mechanism of chitosan-based nanofibers (CNFs) on bacterial membranes.
• To evaluate the efficacy of CNFs against Gram-negative and Gram-positive bacteria.
• To explore the potential of CNFs as bioactive food packaging materials.

Main Methods:

• Electrospinning of chitosan to produce nanofibers (CNFs).
• Testing CNF antibacterial activity against *Escherichia coli*, *Salmonella* Typhimurium, *Staphylococcus aureus*, and *Listeria innocua*.
• Analyzing bacterial membrane damage using transmission electron microscopy (TEM) and detecting intracellular component leakage (proteins, DNA).

Main Results:

• CNFs effectively reduced bacterial viability across tested species.
• Interaction between CNFs and negatively charged bacterial cell walls led to membrane rupture.
• TEM confirmed pore formation and leakage of intracellular components, indicating membrane permeabilization and perforation.

Conclusions:

• CNFs exhibit a potent antibacterial mechanism by disrupting bacterial membranes.
• Chitosan acts as a bacterial membrane disruptor and perforator.
• CNFs show promise for application in bioactive food packaging to enhance food safety and shelf life.