Nanodelivery of nisin by homogeneous protein-based particles

Abstract

Nisin is a widely used antimicrobial peptide with strong inhibitory activity against Gram-positive bacteria and growing 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 contents from environmental exposure, thus improving stability and enabling controlled release. In this study, yeast virus–like particles were explored as a nanodelivery system for nisin, with antibacterial activity and cytotoxicity evaluated. Nisin was successfully loaded into three types of yeast virus-like particles (Y-L-A, Y-L-BC, and B-L-BC), achieving 76.8–89.3% loading capacity while preserving particle sizes of 35.0–50.6 nm and a symmetrical spherical morphology. Nisin-loaded nanoparticles demonstrated antibacterial activity against Gram-positive bacteria, with the strongest inhibitory effect against Streptococcus pyogenes , while activity against Gram-negative bacteria remained low. Compared with free nisin, VLP-associated nisin exhibited moderately higher (1.2-10.1-fold) minimum inhibitory concentration values. Studies using the A549 human lung carcinoma epithelial cell line demonstrated that nisin-induced cytotoxicity was delayed when nisin was loaded into Y-L-BC and B-L-BC nanoparticles. These findings confirm the suitability of yeast virus–like nanoparticles for loading and time-constrained release of nisin, constituting a promising platform for nisin nanodelivery.