In the present work, the bactericidal efficacy and mechanism of slightly acidic electrolyzed water (SAEW) on L. monocytogenes were evaluated. The results showed that the strains of L. monocytogenes were killed completely within 30 s by SAEW whose available chlorine concentration (ACC) was higher than 12 mg/L, and it was confirmed that ACC is the main factor affecting the disinfection efficacy of SAEW. Moreover, our results demonstrated that SAEW could destroy the cell membrane of L. monocytogenes, which was observed by SEM and FT-IR, thus resulting in the leakage of intracellular substances including electrolyte, protein and nucleic acid, and DNA damage. On the other hand, the results found that SAEW could disrupt the intracellular ROS balance of L. monocytogenes by inhibiting the antioxidant enzyme activity, thus promoting the death of L. monocytogenes. In conclusion, the bactericidal mechanism of SAEW on L. monocytogenes was explained from two aspects including the damage of the cell membrane and the breaking of ROS balance.

It is inevitable for polyphenols and polysaccharides to interact during food preparation. Modifications in microstructure can lead to changes in the physical and chemical properties of food systems, which in turn may influence the nutritional characteristics and functional activities of the food. Recent studies have shown that, in addition to traditional Chinese medicine compounds, certain natural polysaccharides and polyphenols exhibit significant anti-inflammatory and antioxidant properties. These compounds are also associated with beneficial therapeutic effects for the prevention and treatment of acute lung injury. The objective of this study was to examine the synergistic antioxidant effects of chlorogenic acid (CA) and Lycium barbarum polysaccharide (LBP) in various ratios, along with their combined antioxidant and anti-inflammatory effects on LPS-induced inflammation in rat alveolar macrophages. Using the Combination Index (CI), which quantifies the synergistic or antagonistic effect of two substances, all four combinations showed synergistic antioxidant properties over a range of concentrations by in vitro antioxidant property experiments. However, based on comparing them, the four group ratios exhibited the highest antioxidant activity of the infusion at CA:LBP = 1:7, indicating synergistic interactions (CI < 1). In addition, the antioxidant and anti-inflammatory effects of the CA-LBP complex were observed to alleviate cellular inflammatory injury by reducing LPS-induced nitric oxide and reactive oxygen species production and inhibiting the release of inflammatory factors such as TNF-α and IL-6.

Prussian Blue Nanoparticles (PBNPs)-based dual-mode immunochromatographic assays (ICAs) were developed for the detection of norfloxacin (NOR) in animal-derived foods. The assays used the inherent bright blue color and peroxidase-like catalytic activity of PBNPs. The visual limit of detection (vLOD) of the developed ICAs were both determined to be 1 ng mL⁻¹. The calculated limit of detection (cLOD) of the ICA based on the inherent bright blue color of PBNPs was 0.5 ng mL⁻¹, while that of the ICA using the peroxidase-like catalytic activity of PBNPs was 0.34 ng mL⁻¹. Analysis of spiked samples demonstrated that NOR could be effectively detected in pork, chicken, beef, sea bass and shrimp, with recoveries ranging from 80.43 % to 106.33 %. The results showed strong correlation with those obtained by HPLC, with R² values of 0.9653 and 0.9715, respectively. Therefore, this study established a sensitive, accurate, rapid and cost-effective method for detecting NOR in animal-derived foods.