Nanodelivery of Nisin by Homogeneous Protein-based Particles

Background Nisin is a widely used antimicrobial peptide with strong inhibitory activity against Gram-positive bacteria and has attracted increasing interest for broader biomedical applications. However, its practical use is limited by susceptibility to environmental conditions, reduced stability, and rapid inactivation. Encapsulation has emerged as an effective strategy to overcome these limitations by protecting such bioactive peptides from environmental exposure, improving their stability, and enabling controlled release. Protein-based nanoparticles derived from viruses represent an attractive encapsulation platform due to their homogeneous size, biocompatibility, and ability to encapsulate and protect bioactive molecules without compromising structural integrity. In this study, yeast virus–like particles were explored as a nanodelivery system for nisin, and their antibacterial activity and cytotoxicity were evaluated. Results Nisin was successfully encapsulated into three types of yeast virus-like particles, achieving 77.1–89.3% encapsulation efficiency while preserving particle size and morphology. Nisin-loaded nanoparticles demonstrated antibacterial activity against Gram-positive bacteria, with the most pronounced inhibitory effect against Streptococcus pyogenes . The antibacterial activity against Gram-negative bacteria was nevertheless low. Compared with free nisin, encapsulated nisin exhibited moderately higher (1.2–10.1 fold) minimum inhibitory concentration values. Cytotoxicity studies involving the A549 human lung carcinoma epithelial cell line demonstrated that, while free nisin reduced cell viability, encapsulation in two differently prepared nanoparticles (Y-L-BC and B-L-BC) delayed nisin cytotoxicity. Conclusions Yeast virus–like nanoparticles represent a promising platform for nisin nanodelivery, preserving antibacterial activity while reducing immediate cytotoxicity through encapsulation. These findings highlight the potential for controlled nisin delivery in antimicrobial and biomedical applications.