Green-synthesized nickel oxide nanoparticles from tea: A dual-action antibiofilm and anti-quorum-sensing activities against selected foodborne pathogens

Basbus, Maryam; Mirpour, Mirsasan; Faezi Ghasemi, Mohammad; Rasti, Behnam

doi:10.22104/mmb.2026.8491.1212

Green-synthesized nickel oxide nanoparticles from tea: A dual-action antibiofilm and anti-quorum-sensing activities against selected foodborne pathogens

Articles in Press

Document Type : Research Paper

Authors

Maryam Basbus

Mirsasan Mirpour

Mohammad Faezi Ghasemi

Behnam Rasti

Department of Microbiology, La.C., Islamic Azad University, Lahijan, Iran

10.22104/mmb.2026.8491.1212

Abstract

Foodborne pathogens pose a persistent threat to public health due to their ability to form biofilms and regulate virulence through quorum sensing (QS). This study evaluated the antibacterial, antibiofilm, and QS-inhibitory activities of nickel oxide nanoparticles (NiONPs) green-synthesized using black tea (NiONPs-BT) and green tea (NiONPs-GT) extracts against Staphylococcus aureus, Escherichia coli, and Listeria monocytogenes. Nanoparticles were comprehensively characterized using UV-Visible spectroscopy, X-ray diffraction (XRD), Dynamic light scattering (DLS), zeta potential analysis, Fourier transform infrared (FTIR), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Antibacterial activity was assessed via minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays, while biofilm inhibition was evaluated using the crystal violet method at sub-MIC and MIC concentrations. Changes in gene expression of biofilm- and QS-related genes were analyzed by quantitative real-time PCR (qPCR). NiONPs-BT exhibited superior colloidal stability (-44.4 mV) and a larger crystallite size (31.3 nm) compared to NiONPs-GT (-20.7 mV; 29.8 nm). Notably, biofilm inhibition reached up to 92.3% with NiONPs-BT against L. monocytogenes at MIC, with substantial inhibition observed even at sub-MIC concentrations. qPCR analysis revealed significant downregulation of key virulence genes, including icaA (0.084-fold), csgD (0.21-fold), and agrB (0.06-fold), indicating transcriptional interference with biofilm and QS-associated regulatory networks. These findings demonstrate that tea-mediated NiONPs, particularly NiONPs-BT, effectively inhibit biofilm formation and suppress the expression of QS-associated and biofilm-related genes, suggesting their potential as anti-virulence agents by indirect mechanisms. This sustainable, phytochemical-based nano strategy needs further investigation as a potential alternative for addressing biofilm persistence and QS-regulated virulence. However, comprehensive toxicity studies should be considered before any food industry-related applications.

Keywords

Nickel oxide nanoparticles

Green synthesis

Quorum sensing associated gene expression

Biofilm inhibition

Foodborne pathogens

Subjects