Norovirus (NoV) is the predominant cause of foodborne illness globally; current detection methods are typically expensive, have inadequate sensitivities, and utilize biological receptors with poor stability. Therefore, accurate, cost-effective, and highly stable detection methods are needed to screen for NoV in foods. We developed molecularly imprinted polymer nanoparticles (nanoMIPs) to detect NoV using a small target epitope (12 amino acids) with a solid-phase synthesis approach. The performance of three batches of nanoMIPs with varying monomer compositions (nanoMIP-1, -2, and -3) were compared both experimentally and computationally. Surface plasmon resonance examined nanoMIP binding affinity to norovirus virus-like particles (NoV-LPs), whereby nanoMIP-1 had the lowest K_D value of 0.512 μM. This is significant, as traditional targets for generation of norovirus ligands previously reported were generated against drastically larger norovirus capsid segments that have limitations in ease of production. Further, an electrochemical sensor was developed by covalently attaching the nanoMIPs to glassy carbon electrodes. In agreement with our predictions from density functional theory simulations, electrochemical impedance spectroscopy showed a sensitive response toward NoV-LPs for nanoMIP batches tested; however, nanoMIP-1 was optimal, with an excellent detection limit of 3.4 pg/mL (1.9 × 10⁵ particles/mL). Due to its exceptional performance, nanoMIP-1 was immobilized to screen-printed electrodes and utilized within a thermal sensor, where it exhibited a low detection limit of 6.5 pg/mL (3.7 × 10⁵ particles/mL). Crucially, we demonstrated that nanoMIP-1 could detect NoV in real food samples (romaine lettuce) by using electrochemical and thermal sensors. Consequently, the study highlights the exceptional potential of nanoMIPs to replace traditional biological materials (e.g., antibodies) as sensitive, versatile, and highly stable receptors within NoV sensors.

Biofilm production by foodborne pathogens poses significant challenges to food safety and quality, leading to contamination, deterioration, and substantial economic losses for the food industry. Traditional biofilm control methods, such as chemical disinfectants, antibiotics, and preservatives, are sometimes ineffective against persistent biofilms, raising concerns about antimicrobial resistance and the accumulation of chemical residues. Lactic acid bacteria (LAB) have emerged as attractive natural biocontrol agents due to their ability to produce a wide range of antimicrobial secondary metabolites, including bacteriocins, organic acids, hydrogen peroxide, and biosurfactants. This paper thoroughly examines the effect of LAB and their metabolites in preventing and destroying biofilms generated by bacteria relevant to food systems, including Listeria monocytogenes, Salmonella enterica, Escherichia coli, and Pseudomonas spp. The processes causing LAB-mediated biofilm attenuation are thoroughly investigated, including competition for nutrients and adhesion sites, interference with quorum sensing (QS), and metabolic inhibition. Furthermore, recent breakthroughs in LAB-based techniques for food preservation and facility hygiene are discussed, including the creation of LAB-derived antimicrobial coatings, biosurfactant-based cleaning agents, and probiotic bio-coatings for industrial sanitation. The incorporation of nanotechnology has enhanced LAB applications by enabling the creation of LAB-mediated metallic nanoparticles and encapsulated formulations that improve metabolite stability and facilitate controlled release. The combination of LAB metabolites, natural preservatives, and eco-friendly materials in active packaging provides sustainable alternatives to synthetic chemicals. Overall, this review emphasizes the potential of LAB and their bioactive derivatives as environmentally friendly and practical tools for controlling biofilms and preserving food, thereby promoting safer food production systems and accelerating the food industry’s transition to green, sustainable technologies.

Viral pathogens are a considerable public health burden, and so inactivating viruses in the environment is critical. This study compared the antiviral activity of cinnamaldehyde nanoemulsions (CNE) and cinnamaldehyde oil (CNO) on a non-enveloped norovirus surrogate bacteriophage (MS2) and an enveloped human coronavirus 229E (HuCoV-229E). MS2 bacteriophage and HuCoV-229E were treated with different concentrations of CNE or CNO (0.5–3.5%). After treatment for 1 h, the reduction in MS2 numbers was significantly less for the CNE than for the CNO. For instance, the log reductions in MS2 numbers were 4.02 ± 0.10 and 2.78 ± 0.34 PFU/mL after treatment with 3.5% and 0.5% of CNO, whereas they were only 1.54 ± 0.08 and 0 PFU/mL after treatment with the equivalent CNE, respectively. Conversely, a significant reduction in HuCoV-229E was observed for the nanoemulsion-based treatment at high cinnamaldehyde levels. Specifically, when treated with 0.5% cinnamaldehyde, there was a 1.35 ± 0.23 and 3.08 ± 0.17 log PFU/mL reduction for the CNE and CNO treatments, but when treated with 2.5% cinnamaldehyde, there was a 5.98 ± 0.12 and 4.43 ± 0.38 log PFU/mL reduction, respectively. These results suggest that the efficiency of the essential oil as a disinfectant against coronavirus-229E can be increased when it is incorporated in a nanoemulsion at an appropriate concentration. The better efficacy of the nanoemulsion formulations against coronavirus-229E than against MS2 bacteriophage may have been because the cinnamaldehyde oil droplets could penetrate into and deactivate enveloped viruses more effectively than non-enveloped ones.

Human norovirus is the leading cause of foodborne illness globally. One of the challenges in detecting noroviruses is the identification of a completely broadly reactive ligand; however, all detection ligands generated to date target the viral capsid, the outermost of which is the most variable region of the genome. The VPg is a protein covalently linked to the viral genome that is necessary for replication but hitherto remains underexplored as a target for detection or therapeutics. The purpose of this work was to generate nucleic acid aptamers against human norovirus (Norwalk) and cultivable surrogate (Tulane) VPgs for future use in detection and therapeutics. Eight rounds of positive-SELEX and two rounds of counter-SELEX were performed. Five and eight unique aptamer sequences were identified for Norwalk and Tulane VPg, respectively, all of which were predicted to be stable (∆G < −5.0) and one of which occurred in both pools. All candidates displayed binding to both Tulane and Norwalk VPg (positive:negative > 5.0), and all but two of the candidates displayed very strong binding (positive:negative > 10.0), significantly higher than binding to the negative control protein (p < 0.05). Overall, this work reports a number of aptamer candidates found to be broadly reactive and specific for in vitro-expressed VPgs across genus that could be used for future application in detection or therapeutics. Future work characterizing binding of the aptamer candidates against native VPgs and in therapeutic applications is needed to further evaluate their application.

This study investigated the efficacy of low-dose ozone microbubble solution and conventional aqueous ozone as inactivation agents against Tulane virus samples in water over a short period of time. Noroviruses are the primary cause of foodborne illnesses in the US, and the development of effective inactivation agents is crucial. Ozone has a high oxidizing ability and naturally decomposes to oxygen, but it has limitations due to its low dissolution rate, solubility, and stability. Ozone microbubbles have been promising in enhancing inactivation, but little research has been done on their efficacy against noroviruses. The study examined the influence of the dissolved ozone concentration, inactivation duration, and presence of organic matter during inactivation. The results showed that ozone microbubbles had a longer half-life (14 ± 0.81 min) than aqueous ozone (3 ± 0.35 min). After 2, 10, and 20 min postgeneration, the ozone concentration of microbubbles naturally decreased from 4 ppm to 3.2 ± 0.2, 2.26 ± 0.19, and 1.49 ± 0.23 ppm and resulted in 1.43 ± 0.44, 0.88 ± 0.5, and 0.68 ± 0.53 log₁₀ viral reductions, respectively, while the ozone concentration of aqueous ozone decreased from 4 ppm to 2.52 ± 0.07, 0.43 ± 0.05, and 0.09 ± 0.01 ppm and produced 0.8 ± 0.28, 0.29 ± 0.41, and 0.16 ± 0.21 log₁₀ reductions against Tulane virus, respectively (p = 0.0526), suggesting that structuring of ozone in the bubbles over the applied treatment conditions did not have a significant effect, though future study with continuous generation of ozone microbubbles is needed.