Methods to remove dye pollutants with natural enzyme, like horseradish peroxidase (HRP), are still limited due to high costs and low stability levels. The development of such a method with similar enzymatic activity is important and could be helpful in wastewater disposal. A metal organic framework material, Fe-loaded MOF-545 (Fe), was synthesized in our study as a new way to remove dyes due to its peroxidase-like activity. The structural characterizations of Fe-loaded MOF-545(Fe) was investigated using scanning electron microscopy (SEM), UV-Vis absorption spectra, and X-ray diffraction (XRD). The peroxidase-like (POD-like) activity of Fe-loaded MOF-545(Fe) was investigated under different pH and temperature conditions. Because of the Fe added into the MOF-545 structure, the absorption of Fe-loaded MOF-545(Fe) for acid (anionic) dyes (methyl orange (MO)) was better than for basic (cationic) dyes (methylene blue (MB)). The Fe-loaded MOF-545(Fe) could give a significant color fading for MO and MB over a short time (about two hours) with peroxidase-like activity. The remarkable capacity of Fe-loaded MOF-545(Fe) to remove the MO or MB is due to not only physical adsorption, but also degradation of the MO and MB with POD-like activity. Therefore, Fe-loaded MOF-545(Fe) has significant potential regarding dye removal from wastewater.

Probiotics, active microorganisms benefiting human health, currently serve as nutritional supplements and clinical treatments. Periodontitis, a chronic infectious oral disease caused by Porphyromonas gingivalis (P. gingivalis), activates the host immune response to release numerous proinflammatory cytokines. Here, we aimed to clarify Leuconostoc mesenterica (L. mesenteroides) LVBH107 probiotic effects based on the inhibition of P. gingivalis activities while also evaluating the effectiveness of an in vitro P. gingivalis lipopolysaccharide-stimulated RAW 264.7 cell-based inflammation mode. L. mesenteroides LVBH107 survived at acid, bile salts, lysozyme, and hydrogen peroxide conditions, auto-aggregated and co-aggregated with P. gingivalis, exhibited strong hydrophobicity and electrostatic action, and strongly adhered to gingival epithelial and HT-29 cells (thus exhibiting oral tissue adherence and colonization abilities). Moreover, L. mesenteroides LVBH107 exhibited sensitivity to antibiotics erythromycin, doxycycline, minocycline, ampicillin, and others (thus indicating it lacked antibiotic resistance plasmids), effectively inhibited P. gingivalis biofilm formation and inflammation (in vitro inflammation model), reduced the secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β) and inflammatory mediators (NO and PGE₂), and decreased the expression levels of inflammation related genes. Thus, L. mesenterica LVBH107 holds promise as a probiotic that can inhibit P. gingivalis biofilm formation and exert anti-inflammatory activity to maintain oral health.

The assessment of glutathione (GSH) levels is associated with early diagnostics and pathological analysis for various disorders. Among all kinds of techniques for detecting GSH, the colorimetric assay relying on the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) catalyzed by many nanomaterials with peroxidase-like activity attracts increasing attention owing to its outstanding merits, such as high sensitivity and high selectivity. However, the aggregation between the nanomaterials severely hinders the entrance of TMB into the “active site” of these peroxidase mimics. To address this problem, the D-amino acid incorporated nanoflowers possessing peroxidase-like activity with a diameter of 10–15 μm, TMB and H₂O₂ were employed to establish the detection system for determining the level of glutathione. The larger diameter size of the hybrid nanoflowers substantially averts the aggregation between them. The results confirm that the hybrid nanoflowers detection system presents a low limit of detection, wide linear range, perfect selectivity, good storage stability and desired operational stability for the detection of GSH relying on the intrinsic peroxidase-like activity and favorable mechanical stability of the hybrid nanoflowers, indicating that the hybrid nanoflowers detection system has tremendous application potential in clinical diagnosis and treatment.

Nanozymes offer promising alternatives to natural enzymes due to enhanced stability, tunable activity, and cost efficiency, demonstrating therapeutic potential against tumors, infections, and inflammatory disorders. Trichinella spiralis is an important pathogen, which globally prevalent foodborne zoonotic parasite. Chemical drug is commonly used to kill T. spiralis , but there are risks of chemical abuse and drug resistance. Here, we engineered MPG(Fe), a cascade nanozyme formed by covalently conjugating glucose oxidase (GOx) to a metal‐organic framework‐Fe nanozyme (MOF‐525[Fe]) nanozyme via the bifunctional PEG linker. In vitro, MPG(Fe) depleted glucose through GOx‐catalyzed conversion to gluconic acid and H ₂ O ₂ , while MOF‐525(Fe) subsequently transformed H ₂ O ₂ into cytotoxic hydroxyl radicals (•OH). This dual‐action mechanism dose‐dependently killed intestinal‐stage adult worms and newborn larvae (NBL) of T. spiralis . In a BALB/c mouse model of intestinal T. spiralis infection, high‐dose MPG(Fe) reduced the survival of intestinal adult worms to 3.53% of the control value through the synergistic actions of glucose deprivation and hydroxyl radical (•OH)‐mediated oxidative damage. Critically, MPG(Fe) exhibited no tissue toxicity in uninfected mice. Our findings establish enzyme‐mimetic nanozymes as a novel therapeutic platform against zoonotic helminthiases.