Inhibitory Effects of Quercetin-Containing Nanoliposomes Against Listeria Monocytogenes and the Expression of Virulence Genes Acta and Hlya Publisher



Sadeghi K ; Rajabi Z ; Papizadeh M ; Noraei O M ; Soltan Dallal M M
Source: Nanomedicine Research Journal Published:2026

Abstract

Objective(s): Liposomes are nanostructures which can be used for encapsulation and delivery of bioactive agents. Listeria monocytogenes is an important foodborne pathogen with increasingprevalence of antibiotic resistance. Because of the increasing rate of drug-resistance, quercetin, a flavonoid, tend to be a promising new treatment option against some infectious disease considering its antioxidant, free radical scavenging, and antimicrobial properties. The aim of this study was to investigate the inhibitory effects of quercetin-containing nanoliposomes against L. monocytogenes growth and expression of virulence genes actA and hlyA in this pathogen. Methods: Nanoliposomes were synthesized by thin-layer hydration method. Particle size and zeta potential were evaluated by DLS morphology by TEM. The degree of quercetin entrapment was assessed by spectrophotometry. Antimicrobial effects was evaluated by microdilution method and Real-Time PCR was used to study the gene expression in the studied pathogen. Results: Quercetin-containing nanoliposomes with an average size of 324 nm and a zeta potential of-88 mV were synthesized and the rate of quercetin entrapment in nanoliposomes was reported to be 92.5%. Culture-based studies in Mueller Hinton agar highlighted the detectable inhibitory effect of quercetin and quercetin-containing nanoliposomes against L. monocytogenes. Using the 96-well microplate method, the MIC and MBC of quercetin-containing nanoliposomes were reported to be 812.7 mg/ml, and the MIC and MBC of free quercetin were reported to be 625.15 mg/ml. Additionally, a considerable decrease of expression of the biofilm-associated genes; hlyA and actA, was observed in the treated samples compared to the control group. Conclusions: Quercetin-containing nanoliposomes have detectable antibacterial properties against Listeria monocytogenes when compared to free quercetin. © 2026 Tehran University of Medical Sciences. All rights reserved.