Synthesis, Characterization, and Anti-Listerial Activity of Chitosan-Stabilized Selenium Nanoparticles

Area of Science:

• Materials Science
• Nanotechnology
• Food Science

Background:

• Listeria monocytogenes (LM) is a significant foodborne pathogen, posing risks to public health.
• Developing effective antimicrobial agents for food preservation is crucial to prevent LM contamination.
• Selenium nanoparticles (SeNPs) have shown antimicrobial properties, but their stability and efficacy can be enhanced through stabilization.

Purpose of the Study:

• To synthesize and characterize chitosan-stabilized selenium nanoparticles (C-SeNPs).
• To evaluate the antibacterial efficacy of C-SeNPs against multidrug-resistant Listeria monocytogenes.
• To assess the potential of C-SeNPs as a food preservative, particularly in seafood.

Main Methods:

• Synthesis of C-SeNPs stabilized by chitosan.
• Characterization of C-SeNPs using techniques such as TEM, SEM, DLS, zeta potential analysis, XRD, ICP-OES, EDX, UV-Vis, and fluorescence spectroscopy.
• Determination of antibacterial activity through MIC, MBC, and time-kill kinetic assays.
• Evaluation of C-SeNPs efficacy in inoculated shrimp and assessment of cytotoxicity.

Main Results:

• C-SeNPs exhibited spherical morphology with a mean hydrodynamic diameter of 173.4 nm and good colloidal stability.
• Elemental selenium (Se0) content was determined to be 29.80 ± 0.35 mg/L.
• C-SeNPs demonstrated potent antibacterial activity against multidrug-resistant LM with MIC and MBC values of 130 and 260 µg/ml, respectively.
• Complete bacterial inactivation was achieved within 24 hours at 2×MIC, with evidence of bacterial membrane disruption.
• C-SeNPs were more effective than potassium sorbate in inhibiting LM growth in shrimp and showed low cytotoxicity.

Conclusions:

• C-SeNPs possess significant antibacterial efficacy against multidrug-resistant Listeria monocytogenes.
• The characterized physicochemical properties of C-SeNPs support their potential as effective antimicrobial agents.
• C-SeNPs show promise as a safe and effective natural preservative for seafood, offering an alternative to conventional methods.