Ozone Research Articles

Wound infection complicated by excessive inflammation remains a persistent challenge in clinical healthcare. Curcumin (Cur), a natural diketone compound, holds therapeutic potential in treating infected wounds. However, its application is limited by poor aqueous dispersibility and low stability. To overcome this dilemma, a versatile capsule as an effective Cur carrier is developed by encapsulating Cur in succinic acid-modified cyclodextrin via hydrophobic interactions, and then loading it into a Zn2+-mediated crosslinked injectable hydrogel for infected wound healing. The composite hydrogel exhibits adjustable rheological properties, modulus, swelling ratios, and degradation rate by control over Zn2+ concentration. This unique tactic enables the sustained Cur release, ensuring long-term antioxidant activity and reactive oxygen species (ROS) scavenging. An in vivo experiment in a rat S. aureus-infected wound model demonstrates that the composite hydrogel significantly accelerates wound healing by massacring bacteria, inhibiting inflammation, as well as promoting collagen deposition and angiogenesis. Overall, this effort paves the way for arming Cur, offering a potent antibiotic-free candidate for bacteria-invaded wound management.

Free oxygen radicals released in the body as a result of various metabolic processes could lead to the so-called oxidative stress in cells, which is a precursor to various types of cancer. Protecting cells from oxidative stress is an important step in the prevention of cancer. Nature has a large supply of compounds with powerful antioxidant properties. One of them is caffeic acid. In the present study, caffeic acid was combined to obtain bioconjugates with analogs of the natural peptide with proven antitumor properties (KLAKLAK)₂. Here we report the antioxidant potential of these molecules as it was investigated with the well-known from the literature DPPH method, in search of a synergistic effect between the two pharmacophores of the molecule. The obtained results identify Si18 (Caf-(KnLAKnLAK)2-NH2) as the lead candidate approaching the caffeic acid benchmark under the tested conditions with EC₅₀ = 0.0178 mM.

Analysis of persistent free radicals and reactive oxygen species of pork after thermal processing using the electron paramagnetic resonance method

Mechanistic study of Cr(VI) reduction by functionalized biochar: Distinct roles of persistent free radicals, ascorbate moieties, and oxygen functional groups

Liquid-phase determination of Arabidopsis respiration and photosynthesis using Clark-type O2 electrodes.

HMGB2 regulates pyroptosis of smooth muscle cells in aortic dissection by modulating ROS-TLR4-NF-κB pathway.

Growth, photosynthesis, redox homeostasis, secondary metabolism and metabolomic changes of Pinellia ternata under antibiotic stress: A comparative study of oxytetracycline, norfloxacin and sulfamethazine.

Graphite edge-sites induced by porosity engineering for high active oxygen reduction reaction

Multifunctional nanoliposome-loaded hypoxia-activated evofosfamide: improving antitumor activity and ferroptosis in pancreatic adenocarcinoma.

Hadal amphipods, which play a vital role in deep-sea ecosystems, harbor gut microbiota that significantly influence host physiology and environmental adaptation. However, understanding of the culturable gut fungi remains limited, particularly their response to the deep-sea osmotic environment. Here, this study reports the successful isolation of Aspergillus sydowii XTO612 from the gut of Hysterocrates gigas. Comparative physiological profiling with A. sydowii DM1, originating from hadal sediment, revealed significant interspecific divergence in hypo-osmotic stress responses (0.1 M NaCl). Low osmolarity conditions were applied as an environmental stressor, and alterations in secondary metabolites, metabolic activity, micromorphology, and reactive oxygen species were observed in the two A. sydowii strains under varying osmotic pressures. The results showed enhanced stress responsiveness in A. sydowii XTO612. Transcriptomic analyses under hypo-osmotic conditions revealed comprehensive regulatory strategies in A. sydowii XTO612, including modulation of membrane permeability, cell wall restructuring, energy metabolism, and osmolyte biosynthesis pathways to optimize osmotic homeostasis. The divergent osmoregulatory strategies in two conspecific marine fungal strains under identical conditions reveal habitat-driven evolution of distinct osmotic regulation mechanisms, highlighting hypo-osmotic stress as a key factor in shaping natural product biosynthesis.IMPORTANCEHadal amphipods play crucial roles in deep-sea ecosystems, yet their gut fungi remain unexplored, representing a major gap in understanding microbial response strategy in extreme environments. While most studies focus on high-osmotic stress, we reveal the unique hypo-osmotic regulatory mechanisms of Aspergillus sydowii XTO612, a novel gut-derived strain from hadal amphipods. Comparative analyses demonstrate distinct stress responses, including cell wall remodeling, metabolic reprogramming, and osmolyte biosynthesis, highlighting habitat-driven evolutionary divergence. This study significantly broadens our understanding of fungal osmoregulation, providing groundbreaking insights into fungal regulation under low-osmotic conditions, with potential implications for biotechnology and microbial response strategies in the deep sea.

High-entropy layered (oxy)hydroxides (HE-LDHs), with efficient intrinsic activity and ideal "cocktail effect," are considered promising candidates for achieving stable and active oxygen evolution reaction (OER). However, due to the dissolution of high-valence intermediates and unpredictable phase transition during the OER process, it remains challenging to solve the trade-off problems occurring between the stability and activity of HE-LDHs. Herein, HE-LDHs with an intercalation structure constructed on a metal-organic framework with heterointerface confinement are reported, realizing the alleviation of metal dissolution and optimized valence of catalytic sites during the OER process, for highly active and durable water electrooxidation. The prepared HE-LDH@Mn-MIL-100 shows ultralow overpotential of 211mV at 10mA cm-2 and wonderful stability operated in 1.0m KOH for 100h. Besides, the constructed anion exchange membrane water electrolyzer (AEMWE) delivers 1.0Acm-2 at only 2.33V for cell voltage in 1.0m KOH, indicating promising prospects for practical applications. This work provides an innovative strategy in improving high-entropy materials systems by confined ligand release for intercalation and offers new insights for tailoring highly active and stable catalysts for alkaline water electrooxidation.

Young leaves and sprouts of Toona sinensis are widely consumed throughout Asia. However, they are highly perishable, resulting in a short shelf life and limited marketability. Low-temperature storage can extend shelf life but is energy-intensive, restricting large-scale use. Salicylic acid (SA) exhibits preservative properties, representing a promising alternative. In this study, we investigated the effects of 250 μmol SA treatment on postharvest T. sinensis buds and leaves stored at 20 °C for 7 days and compared it to low-temperature storage (4 °C). SA treatment delayed wilting, reduced water loss, suppressed total soluble solid accumulation, and inhibited active oxygen free radical and malondialdehyde production compared to the untreated controls at room temperature while outperforming low-temperature storage. The treated buds also maintained higher antioxidant enzyme activity and preserved non-enzymatic antioxidant compounds, including ascorbic acid, polyphenols, and flavonoids. Although total amino acid content steadily increased under SA treatment, individual amino acids greatly fluctuated. SA treatment reduced nitrate reductase and glutamate dehydrogenase activities, as well as NO2•− levels, indicating its effects on nitrogen metabolism. Our findings indicate that SA improves the postharvest quality of T. sinensis buds during room-temperature storage, providing a theoretical basis for applying SA as a storage agent for T. sinensis buds.

Abstract Peanut ( Arachis hypogaea L.) is a globally important crop; however, its productivity is increasingly threatened by heat stress, exacerbated by global warming. Developing heat‐tolerant peanuts is crucial for sustainable production amidst rising temperatures. Unlike commercial cultivars, wild‐derived peanuts possess broader genetic diversity, being naturally adapted to an array of challenging climatic conditions. Antioxidant activity and reactive oxygen species (ROS) regulation are potential indicators of heat tolerance. Studies on enzymatic activity in peanuts have focused on commercial cultivars, leaving a research gap regarding the antioxidant defense mechanism in wild relatives. This study aimed to identify peanut genotypes with superior antioxidant performance and classify their response to heat stress by increasing activity of specific enzymes to scavenge ROS. The experiment was conducted in growth chambers, using 20 peanut genotypes, 12 wild‐derived and eight commercial cultivars. Heat stress (35/22°C, day/night) was imposed for 7 days at 60 days after planting, following pre‐ and post‐stress conditions of 30/20°C (day/night). Leaf samples were collected before, during, and after heat stress. Enzymatic activities of superoxide dismutase, catalase, and ascorbate peroxidase, alongside hydrogen peroxide levels, were analyzed. Upregulation of antioxidant activities under heat stress and recovery periods highlighted their role in detoxifying ROS. AU NPL 17, BatKemp1, IpaCor2, IpaDur2, IpaDur3, MagDur1, and ValSten1 exhibited superior antioxidant enzyme activity, suggesting their potential for heat tolerance. Results also indicated different mechanisms used by peanut genotypes to scavenge ROS, such as balanced ROS scavenging, prioritization of peroxisomal or chloroplast/cytosol detoxification, and compensatory mechanisms.

Abstract. We extended the Linearized ozone scheme – LINOZ in the ICON (ICOsahedral Nonhydrostatic) – ART (the extension for Aerosols and Reactive Trace gases) model system to include NOy formed by auroral and medium-energy electrons in the upper mesosphere and lower thermosphere, and the corresponding ozone loss, as well as changes in the rate of ozone formation due to the variability of the solar radiation in the ultraviolet wavelength range. This extension allows us to realistically represent variable solar and geomagnetic forcing in the middle atmosphere using a very simple ozone scheme. The LINOZ scheme is computationally very cheap compared to a full middle atmosphere chemistry scheme, yet provides realistic ozone fields consistent with the stratospheric circulation and temperatures, and can thus be used in climate models instead of prescribed ozone climatologies. To include the reactive nitrogen (NOy) produced by auroral and radiation belt electron precipitation in the upper mesosphere and lower thermosphere during polar winter, the so-called energetic particle precipitation indirect effect, an upper boundary condition for NOy has been implemented into the simplified parameterization scheme of the N2O/NOy reactions. This parameterization, which uses the geomagnetic Ap index, is also recommended for chemistry-climate models in the CMIP6 experiments. With this extension, the model simulates realistic “tongues” of NOy propagating downward in polar witner from the model top in the upper mesosphere into the mid-stratosphere with an amplitude that is modulated by geomagnetic activity. We then expanded the simplified ozone description used in the model by applying LINOZ version 3. The additional ozone tendency from NOy is included by applying the corresponding terms of the version 3 of LINOZ. This NOy, coupled as an additional term in the linearized ozone chemistry, led to significant ozone losses in the polar upper stratosphere in both hemispheres which is qualitatively in good agreement with ozone observations and model simulations with EPP-NOy and full stratospheric chemistry. In a subsequent step, the tabulated coefficients forming the basis of the LINOZ scheme were provided separately for solar maximum and solar minimum conditions. These coefficients were then interpolated to ICON-ART using the F10.7 index as a proxy for daily solar spectra (UV) variability to account for solar UV forcing. This solar UV forcing in the model led to changes in ozone in the tropical and mid-latitude stratosphere consistent with observed solar signals in stratospheric ozone.

A Novel Pretreatment for Eucalyptus by Cooking with Active Oxygen and Solid Alkali in γ-Valerolactone/H ₂ O Binary System: Experimental and Mechanism Study

Objective: The objective of this study was to comparatively evaluate the post-thaw sperm quality of Boer and Anglo-Nubian goats using semen samples in which seminal plasma was removed by centrifugation and subsequently diluted with a Tris-based egg yolk extender, or directly diluted with the commercial liposome-based extender OptiXcell® without prior centrifugation. Materials and Methods: Semen samples were collected from five adult Boer and five adult Anglo-Nubian goats using an artificial vagina, with collections performed five times per week. The collected semen samples were divided into two equal portions. The first portion was centrifuged to remove seminal plasma prior to dilution with a Tris–egg yolk (TEY) extender (Boer-TEY and Anglo-Nubian-TEY), whereas the remaining portion was directly diluted with OptiXcell® (Boer- OptiXcell and Anglo-Nubian- OptiXcell). All samples were frozen, and post-thaw evaluations were performed. Sperm motility parameters were assessed using computer-assisted sperm analysis (CASA), while plasma membrane integrity, acrosome integrity, mitochondrial activity, viability, and reactive oxygen species (ROS) levels were evaluated by flow cytometry. Results: Post-thaw CASA analysis revealed that total motility (MOT, %) was significantly higher in Boer goat spermatozoa diluted with the TEY extender compared to those diluted with OptiXcell® (p0.05). Progressive motility (%) and all velocity-related kinematic parameters (VAP, VSL, VCL, ALH, BCF, STR, LIN, and WOB) showed no significant differences among groups (p>0.05). Flow cytometric assessments indicated no significant differences in plasma membrane integrity (%), acrosome integrity (%), high mitochondrial activity (%), or viability (%) between groups (p>0.05). In contrast, the proportion of spermatozoa with intracellular reactive oxygen species (ROS) was significantly lower in Boer goat spermatozoa diluted with the TEY extender (p

BackgroundParkinson’s disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons, primarily due to mitochondrial dysfunction. Current treatments focus on managing symptoms but are unable to regenerate neurons. Human dental pulp stem cells (hDPSCs) offer a promising source for neurodegenerative therapy due to their accessibility and neuro-supportive properties. However, research on the mitochondrial characteristics of hDPSCs and their therapeutic potential remains limited. This study investigates the capacity of mitochondria isolated from hDPSCs to restore mitochondrial function and promote neuronal recovery and function in a PD cellular model.MethodshDPSCs were isolated and characterized for mesenchymal stem cell properties. Mitochondria were isolated, quantified, and assessed for viability and morphology using MitoTracker staining and transmission electron microscopy. Mitochondrial uptake and functional recovery were evaluated in a PD cellular model using MPP⁺-treated differentiated SH-SY5Y cells. Mitochondrial function was assessed by measuring Complex I activity, ATP production, and reactive oxygen species (ROS) levels. Neuroregeneration and synaptic function were analyzed through neurite length, growth-associated protein 43 (GAP43) and tyrosine hydroxylase (TH), Synaptophysin (SYP), dopamine transporter (DAT), calcium imaging, and mitochondrial dynamics.ResultsIsolated hDPSC-derived mitochondria were mostly viable, spherical, and displayed immature cristae. In MPP⁺-treated SH-SY5Y cells, mitochondrial transfer restored Complex I activity, elevated ATP production, and reduced ROS. Treated cells also showed significantly longer neurites and increased expression of GAP43, TH, SYP, and DAT. Calcium imaging revealed restored intracellular calcium responses upon stimulation. Mitochondria from hDPSCs localized in both cell bodies and neurites and remained distinct from damaged host mitochondria, supporting synaptic function.ConclusionsMitochondria derived from hDPSCs can restore bioenergetic function, reduce oxidative stress, and promote structural and functional recovery in a PD cellular model. These findings highlight the foundational therapeutic potential of hDPSC-derived mitochondria as a regenerative approach for neurodegenerative diseases.

Tailoring the coordination number of active sites can potentially shift the oxygen evolution reaction (OER) pathway from the traditional adsorbate evolution mechanism (AEM) to the highly active lattice oxygen mechanism (LOM), but effective synthesis approaches are lacking. Herein, we demonstrate a phase transformation strategy to precisely engineer the coordination modes of Ir loaded in zeolitic imidazolate frameworks (ZIFs), which are subsequently converted into two Ir-doped Co3O4 with distinct coordination numbers of Ir (Ir1Ox-Co3O4, x = 4, 6) via air calcination. Comprehensive studies reveal that Ir1O6-Co3O4, featuring a higher Ir-O coordination number, intensifies the Ir-O covalency, activates the lattice oxygen participation, and reduces the thermodynamic barrier following a dual-metal-site lattice oxygen mechanism (DMSM-LOM), while Ir1O4-Co3O4 adheres to the AEM pathway. Consequently, Ir1O6-Co3O4 exhibits a low overpotential of 253 mV at 10 mA cm-2 and superior stability over 200 h, with mass activity approximately 3.4 and 17.3 times greater than those of Ir1O4-Co3O4 and commercial IrO2, respectively. This work not only provides a synthetic strategy for precise coordination number engineering of active sites but also establishes a direct correlation between the coordination environment and the reaction pathway, offering new insights into the rational design of high-performance OER catalysts.

Proton exchange membrane water electrolysis is promising for green hydrogen production, but the sluggish oxygen evolution reaction (OER) and the poor stability of iridium-free OER electrocatalysts hinder its application. Herein, non-metallic element germanium (Ge) is doped into rutile RuO2 nanoparticles to synthesize an active and stable Ru-based acidic OER electrocatalyst. The optimized catalyst (Ge0.1Ru0.9O2) exhibits an ultralow overpotential of 161 mV at 10 mA cm-2 and undergoes a long-term stability test of 650 h at 100 mA cm-2, with a decay rate of 0.164 mV h-1. The high performance is attributed to the isomorphic substitution of Ge, which possesses a slightly smaller ionic radius (53 pm) than Ru (64 pm) and the same valence state (4+), and can donate electrons to Ru, and enhance the structural stability. In situ attenuated total reflection-surface enhanced infrared absorption spectroscopy (ATR-SEIRAS), operando isotropic differential electrochemical mass spectrometry (DEMS), and first-principles calculations reveal that, compared to pristine RuO2, the Ge dopants further unexpectedly facilitate water dissociation and accumulate abundant ─OH group as reactants on electrocatalysts surface. This work gives insights to non-metallic cation doping and interfacial water dissociation for the design of active and robust Ru-based electrocatalysts for acidic water splitting.

Urban driving conditions characterized by frequent start-and-stop operations challenge the dynamic responsiveness of three-way catalysts (TWCs), and the rapid response to oxygen is crucial to buffering air-fuel ratio fluctuations. Herein, we synthesized nonstoichiometric Mn1.5Fe1.5O4 (MF) spinel with excellent oxygen storage capacity and introduced it into Rh/CeO2-ZrO2-Al2O3 (Rh/CZA) via high-energy ball milling to form the composite structure TWCs. The catalysts significantly show a wide operating window and similar steady-state catalytic effects under lean-rich burn oscillating conditions (λ = 0.98-1.02; switching frequency, 1 Hz). MF incorporation not only retains its excellent oxygen storage capacity but also results in the generation of abundant oxygen vacancies on MF-CZ heterogeneous interfaces, thus synergistically promoting the rapid formation and migration of active oxygen species. Furthermore, the lower oxygen vacancy formation energy (Eform) for the Mn-Ov-Ce bridged structure promotes the rapid formation of interfacial oxygen vacancies and the facile desorption of active oxygen species, which is important to enhance the reaction rates and buffer air-fuel ratio fluctuations. This study presents a strategy to enhance the dynamic responsiveness of TWCs and offers critical insights into the formation mechanisms and migration of the active oxygen species process on heterogeneous interfaces.