Tehran University of Medical Sciences Nanomedicine Research Journal 2476-3489 11 1 2026 03 01 Inhibitory Effects of Quercetin-containing Nanoliposomes Against Listeria Monocytogenes and the Expression of Virulence Genes actA and hlyA 51 59 737694 10.22034/nmrj.2026.01.006 EN Sedighe Dehghan Morabadi Food Microbiology Division, Pathobiology Department, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 0009-0006-1117-9175 Kaveh Sadeghi Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran 0000-0001-7746-6632 Zahra Rajabi Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran 0000-0003-4970-3068 Moslem Papizadeh Microbial Biotechnology Department, Biotechnology and Modern Medicine Organization, Tehran, Iran 0000-0002-0966-1951 Omid Mangane Noraee Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran 0000-0003-4487-3148 Mohammad Mehdi Soltan Dallal Food Microbiology Division, Pathobiology Department, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran 0000-0002-3421-3974 Journal Article 2025 08 08 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.<br>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.<br>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.<br>Conclusions: Quercetin-containing nanoliposomes have detectable antibacterial properties against Listeria monocytogenes when compared to free quercetin. https://www.nanomedicine-rj.com/article_737694_4eee956d3ebb25112e595a4b1aed68de.pdf