This study investigates the impact of catalase (CAT) on the rheological properties of wheat gluten by analyzing CAT-induced structural changes in gluten proteins to uncover the mechanisms behind these modifications. The results showed that CAT significantly enhanced the storage modulus (G') and loss modulus (G″) of gluten while reducing creep strain and recovery strain. The most pronounced effects were observed with the addition of 250 U/g CAT for 30 min. CAT facilitated the formation of larger molecular weight aggregates in gluten proteins and increased the content of disulfide bonds and β-sheets, reaching 11.42 μmol/g and 45.78 %, respectively, after treatment with 250 U/g CAT for 30 min. These structural changes reduced the hydrophobic regions of gluten, lowered gluten extractability, and enhanced the compactness and stability of the gluten network. These effects substantially influenced the rheological behavior of wheat gluten, offering new insights and practical guidance for improving gluten-based products using CAT.

Meta-transcriptomics data supported by biofilm physico-chemical parameters unravelled the molecular and biochemical processes utilized by multicomponent intertidal biofilms to endure cobalt toxicity. Findings indicated activation of influx (BtuB, ABC-type transporters) and efflux pumps (RND, CZC) to maintain metal ion homeostasis. Enhanced specific activity of antioxidant enzymes namely catalases and peroxidases (KatG, SodA) mitigated oxidative damage. Heightened synthesis of capsular polysaccharide components, specifically uronic acid and carbohydrate via PEP-CTERM sorting system, wzy pathway and glycosyltransferases protected biofilms against cobalt exposure. Despite chlorophyll biosynthesis genes being upregulated, metal toxicity impeded chlorophyll replenishment. Principal pathways associated with iron acquisition (AfuA), energy metabolism (AtpG), general metabolic activities (FruK, NifD, coABC) and central dogma regulation (DPS, AsrR, RRM) were activated to combat cobalt toxicity. This investigation offered novel insights into the regulatory network employed by intertidal microphytobenthic communities for maintaining cobalt homeostasis and underlined the basis for their application as biomarkers for estuarine cobalt pollution.

Bee population decline is associated with various stressors, including exposure to pollutants. Among these, titanium dioxide (TiO2), an emerging nanoparticle (NP) pollutant, potentially affects living organisms, including bees. This study evaluates the impact of TiO2 NPs ingestion (1.35 or 13.5 µg/mL) on the behavior and physiology of the stingless bee Partamona helleri. X-ray spectroscopy confirmed the presence of Ti in the bees' gut, and 3D X-ray microscopy revealed a reduction in body volume. Although survival, food consumption, flight, and respiration were unaffected. In addition, bees exposed to 13.5 µg/mL of TiO2 NPs exhibited reduced walking distances. TiO2 NPs exposure decreased the total hemocyte count, with notable changes in the proportions of specific hemocyte types: decreased the proportions of plasmatocytes in bees exposed to 13.5 µg/mL, and decreased the granulocytes, and increased the prohemocytes in both concentrations. Furthermore, enzymatic activity was affected with increased levels of catalase (CAT), superoxide dismutase (SOD), and ferric-reducing antioxidant power (FRAP), alongside a decrease in glutathione S-transferase (GST) activity. These findings suggest that TiO2 NPs may pose a risk to bee health, highlighting the need for further research to fully understand the implications of nanoparticles exposure on pollinators.

Nanozymes, characterized by enzyme-like activity, have been extensively used in quantitative analysis and rapid detection due to their small size, batch fabrication, and ease of modification. Researchers have combined aptamers, an emerging molecular probe, with nanozymes for biosensing to address the limited reaction specificity of nanozymes. Nanozyme aptasensors are currently experiencing significant growth, offering a promising solution to the lack of rapid detection methods across various fields. Unlike traditional nanozyme research, the development of nanozyme aptasensors is challenging as it requires the design of highly active nanozymes as well as the establishment of efficient and agile interactions between aptamers and nanozymes. Therefore, this review summarizes the active species and catalytic mechanisms of various nanozymes along with classical design options, discussing the future development of nanozyme aptasensors. It is anticipated that this review will inspire researchers in this domain, leading to the design of more enzymatically active nanozymes and advanced nanozyme aptasensors.

Molecular hydrogen is gaining increasing attention as an antioxidant, anti-inflammatory, and antiapoptotic agent. Once considered an inert gas, it reveals current therapeutic potential among others in inflammatory diseases, cancer, and sports medicine, among others. The present review aims to provide a consistent summary of the findings of the last twenty years on the use of molecular hydrogen in major respiratory diseases, including allergies, asthma, COPD, pulmonary fibrosis, lung injury of various origins, as well as cancer and infections of the respiratory tract. In addition, the basic mechanisms through which molecular hydrogen exercises its biological activity on the respiratory system are described.

Stellariae Radix Polysaccharides (SRP, extracted from roots of Stellaria dichotoma var. lanceolata Bge.) was structurally characterized and its potential as both a fruit preservation agent and a hypoglycemic bioactive compound was explored. SRP, containing 73.23 ± 1.02 % total sugar, was separated into two main fractions, SRP-1 (neutral) and SRP-2 (acidic), using DEAE-52 cellulose chromatography, with respective yields of 74.07 ± 0.90 % and 2.93 ± 0.12 %. SRP and its fractions were then analyzed in detail by GPC, HPLC, FT-IR, and NMR, which revealed their key structural features and bioactive potential. In vitro assays indicated SRP has high antioxidant capacity, with DPPH• and ABTS•+ scavenging activities of 70.43 ± 0.09 % and 96.82 ± 0.05 % at 8 mg/mL, respectively. SRP inhibited α-glucosidase (88.60 ± 1.84 %) and α-amylase (75.76 ± 1.74 %) in a dose-dependent manner, underscoring its hypoglycemic properties. Applied as an edible coating for fresh-cut apple, SRP enhanced preservation, reduced weight loss, maintained firmness, and conserved ascorbic acid over 96 h. It also limited malondialdehyde production, reduced electrolyte leakage, protected cell membrane integrity, and mitigated oxidative damage. These findings position SRP as a novel, multifunctional component in food preservation technologies that align with both environmental sustainability and diabetic dietary needs.

Collagen plays a crucial role in platelet activation and thrombosis, yet the underlying mechanisms involving reactive oxygen species (ROS) remain incompletely understood. This study investigated how collagen modulates ROS generation and platelet aggregation both in vitro and in vivo, as well as evaluating the protective effects of antioxidants. In vitro, collagen induced dose-dependent platelet aggregation and increased ROS generation, evidenced by the enhanced EMPO adduct formation detected via electron spin resonance (ESR). In vivo experiments demonstrated that collagen administration significantly accelerated CAT-1 decay, indicating elevated oxidative stress with a transient peak around 1 minute post-treatment. Furthermore, escalating collagen doses correlated with increased ROS generation and reduced survival rates in mice, underscoring collagen's impact on oxidative stress and thrombosis severity. Importantly, treatment with enzymatic antioxidants (superoxide dismutase, catalase) and non-enzymatic antioxidants (DMTU, Tiron, mannitol) significantly attenuated collagen-induced oxidative stress and improved animal survival. Collectively, these findings elucidate the pivotal role of ROS in collagen-induced platelet activation and thrombosis and highlight antioxidants as promising therapeutic candidates for preventing thrombotic disorders and managing cardiovascular risk.

We focused on evaluating oxidative stress as a major mechanism of cell damage in patients with COVID-19 infection by simultaneously assessing standard oxidative stress biomarkers in vivo-for the very first time in this specific combination-alongside typical clinical biomarkers of inflammation. Standard biomarkers were used to evaluate the oxidative stress status and antioxidant activity in the blood plasma of COVID-19 patients and healthy controls. These included TBARSs (Thiobarbituric Acid-Reactive Substances), SOD (Super Oxide Dismutase), CAT (catalase), GRA (glutathione reductase) activities, and AOC (antioxidant capacity). All clinical inflammation data confirmed a highly activated immune response in the tested COVID-19 patients: WBCs (white blood cells) were increased by nearly 100%, LYMs (lymphocytes) increased by ~30%, CRP (C-reactive protein) rose by over 2200%, and the ESR (erythrocyte sedimentation rate) increased by ~320% compared to established maximum control levels. The results confirmed that the infection involved a free-radical-mediated damage mechanism: TBARS levels increased almost 3-fold, the AOC decreased more than 4-fold, SOD was increased nearly 5-fold, CAT was increased by 1.4 times, and GRA was suppressed by 2.5 times. COVID-19 was associated with oxidative stress and suppressed antioxidant activity. All these changes contribute to the severity of the disease, complications, and mortality in COVID-19 patients.

Staphylococcus aureus subsp. anaerobius (SAAN) causes abscesses in small ruminants, known as Morel's Disease. This study describes the presence of SAAN for the first time in Germany and Austria and examines the phylogenetic relationship among these isolates and previously described European and Sudanese ones. A total of 35 sheep and 10 goat isolates from 12 herds in Germany were available for analysis. SAAN isolates from four Polish goats and three Austrian sheep from different herds were included. Genome comparisons and phylogenetic analyses were conducted using core genome multilocus sequence typing. The comparison of the 52 SAAN core genomes revealed a close phylogenetic relationship among most German isolates (n = 38), with allelic differences ≤ 6 in two clusters associated with ST4581. In contrast, distinct clusters of the same ST included the four Polish goat isolates and two ovine isolates from Austria, respectively. A fifth cluster of ST3756 strains was identified on three German farms (six sheep, one goat) and an Austrian sheep. Tight phylogenetic relationships were observed irrespective of the host species. All isolates shared a common set of virulence genes and few known antimicrobial resistance determinants. The introduction of SAAN into herds is mostly unknown, but purchases appear to play a critical role.

Among the various heterocyclic organoselenium compounds, a new class of benzoselenazoles has received great attention due to their chemical properties and biological applications. The ever-growing interest in the five-membered benzoselenazole heterocycles amongst chemists has made commendable impact. These heterocycles are a prominent class of organic molecules that have emerged as potential therapeutic agents for the treatment of a wide range of diseases. Substantial progress has been made in elucidating the complex chemical properties of these heterocycles. Moreover, they have garnered significant importance in a wide range of biological applications. However, despite their biological activities, research on benzoselenazoles remains relatively limited, emphasising the need for further exploration in this area. Hence, considering the importance of benzoselenazoles, this comprehensive review compiles various synthetic procedures, highlighting the recent advances in their synthesis that have been disclosed in the literature. This review would offer chemists an array of information that will assist them in the development of more affordable and effective synthesis processes for benzoselenazoles. Therefore, it is believed that this review would provide relevant context on these achievements and will inspire synthetic organic chemists to use these effective technologies of such heterocycles for the future treatment of diseases caused by oxidative stress. The biological and pharmacological properties of these organoselenium heterocycles, which include their antioxidant, antitumor, and antibacterial activities and their application in Alzheimer's disease treatment and as pancreatic lipase inhibitors, are thoroughly summarized. Finally, this review provides some perspectives on the challenges and future directions in the development of benzoselenazoles as heterocyclic organoselenium compounds.

Halohydroxybenzonitriles (HHBNs) were reported to exist in drinking water as an emerging group of nitrogen-containing aromatic disinfection byproducts (DBPs). The involvement of binding energy with catalase (CAT) as one of molecular descriptors in the quantitative structure-activity relationship model for HHBN cytotoxicity supported that oxidative stress is highly possible to be an essential cytotoxicity mechanism for HHBNs, and the disruption of cellular redox homeostasis may be partly attributed to their interactions towards CAT. However, the relevant evidence is lacking as yet. Thus, in this study, typical biomarkers for oxidative stress and damage in HHBN-treated cells were examined, and the binding interactions between HHBN and CAT were explored. Results indicated that upon exposure to 3,5-dibromo-2-hydroxybenzonitrile, the antioxidant system (e.g., CAT, superoxide dismutase, and glutathione) was disrupted, and excessive reactive oxygen species gave rise to oxidative DNA damage, which further resulted in cell apoptosis. Moreover, the binding interaction between CAT and 3,5-dibromo-2-hydroxybenzonitrile could change the structure and activity of CAT, with the formation of complexes primarily dependent on van der Waals forces and hydrogen bonding. A positive correlation was observed between HHBN cytotoxicity and inhibitory potency on the biological function of CAT, and some unidentified iodinated HHBNs warrant special attention in future owing to their potential high cytotoxicity. The above results contribute to a better understanding of the toxic mechanisms of emerging HHBN DBPs.

Diabetes mellitus is a chronic disease affecting young and old, even though it can be managed with orthodox medicine, which has a series of side effects. Therefore, Dalbergiella welwitschi is one of the medicinal plants that is commonly used for the management of diabetes mellitus and its associated complications. Hence, this study was designed to assess the testicular-protective ability of alkaloid-rich leaf extract of D. welwitschi in streptozotocin-induced type 2 diabetic rats D. welwitshii leaf alkaloid-rich extract was obtained using standard procedure. Streptozotocin was injected into the experimental animals intraperitoneally at a dose of 45 mg/kg body weight to induce type 2 diabetes mellitus. Prior to this, the animals were given 20% (w/v) fructose for one week. Thus, the animals were grouped into five (n = 8), comprising of un-induced rats (NC), diabetic control (DC), diabetic rats treated with low (50 mg/kg body weight) and high (100 mg/kg body weight) doses of D. welwitschi alkaloid-rich leaf extracts (i.e., DWL and DWH respectively) and 200 mg/kg body weight dose of metformin (MET). The animals were sacrificed on the 21st day, blood and testis were harvested and used for the determination of ions (Fe, Cu and Zn), sialic acid, some hormones (testosterone, luteinizing and follicle stimulating), oxidative stress biomarkers [malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and glutathione (GSH)] as well as histological examination. In addition, the results show that diabetic rats placed on DWL, and DWH significantly (p < 0.05) decreased ion levels (Fe, Cu and Zn) and ameliorated oxidative stress biomarkers such as MDA, SOD, CAT, GPx, GST, and GSH. These were supported by the histological examination by improving testicular-protective effects in diabetic rats administered DWL, and DWH. Therefore, it is that assume that the alkaloid-rich leaf extracts of D. welwitschi may offer potential benefits in the treatment of diabetic testicular dysfunction.

Oxidative stress is considered a common underlying mechanism in many retinal degenerative diseases and is often associated with inflammation. The use of dietary supplements containing Saffron has beneficial effects in ocular diseases, though the molecular mechanisms are still unclear. In this study, we investigated how Saffron can exert protective effects against oxidative damage in retinal pigment epithelial cells (ARPE-19) and whether its combination with Elderberry and Melilotus may have additive beneficial effects. ARPE-19 cells were pretreated with Saffron alone or in a mix containing Saffron, Elderberry and Melilotus, then exposed to hydrogen peroxide (H2O2) for 3 h. Afterwards, we evaluated cell viability, oxidative stress and inflammatory status. Our results showed that H2O2 reduced cell viability and total glutathione levels, while increasing caspase-3, caspase-1 and LDH activity. Moreover, H2O2 triggered ROS production, glutathione oxidation and IL-1β secretion. Pretreatments with Saffron alone or with the mix counteract these damaging effects by improving cell viability, reducing oxidative stress and enhancing SOD2 expression. Pretreatment with the mix activated the NRF2 pathway and was more effective than Saffron alone in preventing caspase-1 activation. These findings suggest that the combination of Saffron, Elderberry and Melilotus could have therapeutic potential in the prevention and treatment of retinal degenerative diseases.

Harmful algal blooms are an expanding phenomenon negatively impacting human health, socio-economic welfare, and ecosystems. Such events increase the risk of marine organisms' exposure to algal toxins with consequent ecological effects. In this frame, the objective of this study was to investigate the ecotoxicological potential of three globally distributed dinoflagellate toxins (okadaic acid, OA; dinophysistoxin-1, DTX-1; dinophysistoxin-2, DTX-2) using Artemia franciscana as a model organism of marine zooplankton. Each toxin (0.1-100 nM) was evaluated for its toxic effects in terms of cyst hatching, mortality of nauplii Instar I and adults, and biochemical responses related to oxidative stress. At the highest concentration (100 nM), these toxins significantly increased adults' mortality starting from 24 h (DTX-1), 48 h (OA), or 72 h (DTX-2) exposures, DTX-1 being the most potent one, followed by OA and DTX-2. The quantitation of oxidative stress biomarkers in adults, i.e., reactive oxygen species (ROS) production and activity of three endogenous antioxidant defense enzymes (glutathione S-transferase, superoxide dismutase, and catalase) showed that only DTX-2 significantly increased ROS production, whereas each toxin affected the antioxidant enzymes with a different activity profile. In general, the results indicate a negative impact of these toxins towards A. franciscana with potential consequences on the marine ecosystem.

Oxidative stress is closely related to the occurrence and development of ischaemic stroke. Natural plant polysaccharides have potential value in inhibiting oxidative stress and preventing ischaemic stroke. Here, a novel neutral polysaccharide named LICP009-3F-1a with a Mw of 10,780 Da was separated and purified from Lycium barbarum L. fruits. Linkage and NMR data revealed that LICP009-3F-1a has the following backbone: →4)-β-D-Glcp-(1→6)-β-D-Galp-(1→, with a branched chain of β-D-Galp-(1→3)-β-D-Galp-(1→, α-L-Araf-(1→ and →6)-α-D-Glcp-(1→ connected to the main chain through O-3 of →3,6)-β-D-Galp-(1→. X-ray and SEM analyses showed that LICP009-3F-1a has a semicrystalline structure with a laminar morphology. Thermal property analysis showed that LICP009-3F-1a is thermally stable. In vivo experiments suggested that LICP009-3F-1a could inhibit hypoxia-induced oxidative stress damage by eliminating ROS, reversing and restoring the activities of the antioxidant enzymes SOD, CAT, and GPx, and reducing the expression levels of the HIF-1α and VEGF genes. Blocking the apoptosis genes Bax and Caspase 3 and upregulating the expression of the antiapoptotic gene Bcl-2 protected PC12 cells from hypoxia-induced apoptosis. These results suggest that LICP009-3F-1a may have multiple potential uses in the treatment of IS.

The focus on microalgae for applications in several fields, e.g. resources for biofuel, the food industry, cosmetics, nutraceuticals, biotechnology, and healthcare, has gained increasing attention over the last decades. In this study, we investigate the microbiome of the cultured microalga Tetraselmis chui (T. chui) to highlight their potential for health benefits. In this context, biomolecules like antioxidants play a crucial role in the well-being of living organisms as they metabolise harmful reactive oxygen species (ROS) to reduce oxidative stress. Impaired processing of ROS leads to damaged cells and increases the risk of cancer, inflammatory diseases, and diabetes, among others. Here, we identify, characterise, and test bacterial antioxidants derived from the T. chui microbiome metagenome dataset. We identified 258 genes coding for proteins with potential antioxidant activity. Of those, four novel enzymes are expressed and identified as two superoxide dismutases (SOD), TcJM_SOD2 and TcIK_SOD3, and two catalases (CAT), TcJM_CAT2 and TcIK_CAT3. Extensive analyses characterised all implemented enzymes as active even in concentrations down to 25 ng*ml-1 for the SODs and 15 ng*ml-1 for the CATs. Furthermore, sequence-based analyses assign TcJM_SOD2 and TcIK_SOD3 to iron superoxide dismutases (Fe SODs) and TcJM_CAT2 and TcIK_CAT3 to heme-containing catalases. These candidates are phylogenetically classified within the phylum Pseudomonadota. Regarding the biotechnological potential, a toxicity assay did not indicate any harmful effects. The introduced enzymes may benefit medical applications and expand the potential of microalgae microbiomes. KEY POINTS: • Omics-based discoveries of antioxidant enzymes from Tetraselmis chui microbiome • Two superoxide dismutases and two catalases are identified and tested for activity • Enzyme sensitivity highlights biotechnological potential of microalgae microbiomes.

Oxidative stress plays a major role in the secondary injury of the spinal cord tissue due to the high lipid content of nervous tissue. In the present study, coaxial nanofibers were loaded with the natural antioxidant pyrroloquinoline quinone (PQQ) and used as an implantable drug-delivery system and a scaffold post-SCI. The obtained data show that the concentration of NO and the activity of inducible nitric oxide synthase (iNOS) were significantly (P < 0.05) increased in the spinal cord injury (SCI) group. These levels were significantly decreased following treatment with nanofibers/PQQ. Implantation of nanofibers/PQQ resulted in a significant (P < 0.05) drop in the level of malondialdehyde (MDA) compared to the SCI group. The application of nanofibers loaded with PQQ after SCI caused a significant (P < 0.05) elevation of superoxide dismutase (SOD) and catalase (CAT) activity in the spinal cord tissue. The present work shows the protective role of coaxial nanofibers loaded with PQQ against oxidative stress in spinal cord injury. The reversal of oxidative stress with PQQ can lead to better outcomes following spinal cord injury.

The point of our study was to examine the interaction of ammonia-N poisoning and salinity on serum enzymes and oxidative stress factors of blood and liver in Nile tilapia (Oreochromis niloticus). The 50% lethal concentration (LC50) in 96 h was 0.86 mg/L of ammonia-N. A random allocation was used to divide the fish into 12 treatments. These treatments encompassed various combinations of acute ammonia-N levels (0 and 50% of LC50-96 h), sub-acute ammonia-N levels (30% of LC50-96 h), and salinity levels (0, 4, 8, and 12 ppt). The experimental design employed a factorial arrangement of 3 × 4.The findings revealed that the amounts of aspartate transferase (AST) and alanine transaminase (ALT) in treatments 3 and 4 increased significantly compared to the treatment 2 (4 ppt) and control. Salinity levels did not affect serum glutathione levels (GSH), nevertheless the reduction of serum GSH and levels of total antioxidant capacity (TAC) and superoxide dismutase (SOD) and catalase activities (CAT) in ammonia poisoning treatments, 5 and 9, compared to the control, states ammonia can stimulate oxidative stress in fish. Similar to the serum measurements, increasing salinity in acute ammonia poisoning treatments (5, 6, 7 and 8) caused an increasing effect on the liver TAC value, which was presumably due to the improving effect of salinity in reducing ambient ammonia. The findings indicate that while elevated salinity levels can be beneficial in mitigating the effects of ammonia toxicity in water, the combined presence of salinity, ammonia, and their interaction had detrimental impacts on the physiological well-being of fish over a 96-hour testing period.

Oxidative stress plays a crucial role in various pathological conditions. This study introduces an enhanced model using hydrogen peroxide (H2O2)-induced stress in Galleria mellonella larvae, offering a cost-effective and ethically sound alternative for oxidative stress research. The model bridges in vitro and in vivo studies to identify biomarkers like lipid peroxidation, protein carbonylation, hemocyte count, and antioxidant enzyme activities. Our results show that while G. mellonella larvae tolerated high doses of H2O2, increased susceptibility occurred with prolonged toxicosis and higher concentrations. Acute H2O2 exposure (5.0 M/1st day) led to elevated lipid and protein oxidation and decreased superoxide dismutase activity and hemocyte count, while catalase activity and total antioxidant capacity increased. Despite these defenses, the larvae's antioxidant capacity was insufficient under severe oxidative stress, reducing survival. This study highlights G. mellonella larvae as a promising model for examining reactive oxygen species (ROS)-induced oxidative stress.

In the present study, the effects of coenzyme Q10 (CoQ10), which is widely used in daily life, on the methotrexate (MTX)-induced hepatotoxicity, which is widely used today in malignancies and autoimmune diseases, were examined. Twenty-four female Wistar albino rats were divided into four groups. The group 1 (n = 6) was given 1 mL corn oil by oral gavage (p.o.) during seven days. Group 2 was given 20 mg/kg intraperitoneal (i.p.) MTX only on the first day of the experiment. Group 3 was given 20 mg/kg (i.p.) MTX on the first day of the experiment and 100 mg/kg CoQ10 dissolved in 1 mL corn oil were given by oral gavage during seven days, and group 4 was given 100 mg/kg CoQ10 dissolved in 1 mL corn oil by oral gavage during seven days. At the end of experiment, all animals were euthanized under anesthesia. In the liver tissue, histopathologic analysis on the hematoxylin and eosin (H&E), Masson trichrome, and periodic acid Schiff (PAS) stained sections, apoptotic analysis (% Annexin V positivity) by flow cytometry, and biochemical analysis for oxidative stress markers (GSH, CAT, and TBARS) was performed. According to histopathological analysis, apoptosis, concession, fibrosis, and inflammatory cell infiltration increased in the MTX group and those results significantly decreased in the MTX + CoQ10 groups. As an interesting result, fatty degeneration and TBARS elevation were observed in the MTX + CoQ10 group. As a result, although CoQ10 has protective effects on MTX-induced hepatotoxicity, fatty degeneration due to the combined usage of MTX and CoQ10 should be investigated with further studies.

The black garden ant (Lasius niger) is a widely distributed species across Europe, North America, and North Africa, playing a pivotal role in ecological processes within its diverse habitats. However, the microbiome associated with L. niger remains poorly investigated. In the present study, we isolated a novel species, Paenarthrobacter lasiusi, from the soil of the L. niger anthill. The genome of P. lasiusi S21 was sequenced, annotated, and searched for groups of genes of physiological, medical, and biotechnological importance. Subsequently, a series of microbiological, physiological, and biochemical experiments were conducted to characterize P. lasiusi S21 with respect to its sugar metabolism, antibiotic resistance profile, lipidome, and capacity for atmospheric nitrogen fixation, among others. A notable feature of the P. lasiusi S21 genome is the presence of two prophages, which may have horizontally transferred host genes involved in stress responses. P. lasiusi S21 synthesizes a number of lipids, including mono- and digalactosyldiacylglycerol, as well as steroid compounds that are typically found in eukaryotic organisms rather than prokaryotes. P. lasiusi S21 exhibits resistance to penicillins, lincosamides, fusidins, and oxazolidinones, despite the absence of specific genes conferring resistance to these antibiotics. Genomic data and physiological tests indicate that P. lasiusi S21 is nonpathogenic to humans. The genome of P. lasiusi S21 contains multiple operons involved in heavy metal metabolism and organic compound inactivation. Consequently, P. lasiusi represents a novel species with an intriguing evolutionary history, manifesting in distinctive genomic, metabolomic, and physiological characteristics. This species may have potential applications in the bioaugmentation of contaminated soils.

Soil salinization threatens global crop production. Here, we report that a receptor-like cytoplasmic kinase, CALMODULIN-BINDING RECEPTOR-LIKE CYTOPLASMIC KINASE 3 (CRCK3), plays an essential role in plant salt tolerance via CATALASE 2 (CAT2), a hydrogen peroxide (H2O2)-scavenging enzyme in Arabidopsis (Arabidopsis thaliana). CRCK3 was induced by salt stress, and its knockout mutant displayed a salt-sensitive phenotype compared with wild-type plants. CRCK3 was activated by salt stress in a calcium-dependent manner, and its kinase activity was required for plant salt tolerance. CRCK3 physically interacted with CAT2, and CRCK3-mediated salt tolerance depended on CAT2. Salt treatment significantly induced CAT2 phosphorylation via the action of CRCK3, and this phosphorylation was required for CAT2-mediated H2O2 scavenging to reduce reactive oxygen species (ROS) content and oxidative damage in plants under saline conditions. CRCK3 phosphorylated CAT2 at the Thr209 residue, resulting in elevated catalase activity to reduce ROS accumulation under saline conditions. Therefore, the CRCK3-CAT2 module mediates plant salt tolerance by maintaining redox homeostasis. This study expands our knowledge of how plants respond to salt stress.

Chlorantraniliprole (CAP), a diamide insecticide, is extensively applied to combat pests in various crops. However, the widespread use of insecticides has raised concerns about their potential impact on pollinators. In the present study, we explored the toxic effects of CAP in two important honey bee species, Apis mellifera and Apis cerana. The 48 h LC50 values of CAP for A. mellifera and A. cerana was 256.052 mg/L and 109.709 mg/L, implying that A. cerana is more sensitive to CAP. Prolonged exposure to 40 mg/L CAP significantly impaired sucrose responsiveness and climbing activity in both bee species. Both species showed a decrease in GR activity and GSH content with increasing CAP concentration. By contrast, the activities of GST, CAT, P450 and NAD-MDH were increased in both A. mellifera and A. cerana, but the differences between the 10 mg/L and 40 mg/L treatments were less pronounced in A. mellifera. Moreover, the immune related genes exhibited differential responses to CAP when comparing the two species. Low CAP concentrations led to down-regulation in expression of toll but up-regulation in expression of apideacin and hymeopatecin in A. mellifera, whereas A. cerana exhibited minimal changes in these genes. Additionally, CAP significantly inhibited the expression of ER stress response genes gp-93 and P58 in A. mellifera, while 10 mg/L of CAP promoted P58 expression in A. cerana. Our results highlight species-specific effects with the possible, distinct detoxification mechanisms and immune responses between A. mellifera and A. cerana. These findings serve as a foundation for further evaluating the safety of CAP for honey bee species and offer insights into the scientific use of pesticides.

Stimuli-induced release resulting in biochemical transformations has received a lot of attention due to its application in controlled drug release. In this work, catalase (EC 1.11.1.6) and trypsin (EC 3.4.21.4) were simultaneously encapsulated into a pH-responsive alginate hydrogel. Upon applying electrochemical potential -0.8 V vs Ag/AgCl/KCl resulting in oxygen reduction, which generates a local pH increase, trypsin becomes active. The activated trypsin provides the digestion of catalase within the alginate matrix, stimulating the release of active subunits. Simultaneously with the trypsinolisis of catalase, the pH increase led to hydrogel swelling, allowing for the release of catalase active fragments. Difference in the release behavior was also observed in solutions with different bulk pH values, at which trypsin was or was not active. Labeling of catalase with rhodamine B isothiocyanate was performed for the release observation using confocal fluorescence microscopy and regular fluorescent spectroscopy. The activity of catalase fragments was analyzed using a UV-visible spectrophotometer, following the enzymatic assay toward guaiacol, which is known to be a selective substrate for catalase subunits. Blue native polyacrylamide gel electrophoresis was used to analyze the efficiency of trypsinolysis and the molecular weights of the formed fragments. The proposed signal-stimulated release of bioactive fragments from the alginate hydrogel presents an intriguing model system with the potential for biomedical applications.

Alzheimer's disease (AD) has long proven to be a complex neurodegenerative disorder, with cholinergic dysfunction, oxidative stress, and neuroinflammation being just a few of its pathological features. The complexity of the disease requires a multitargeted treatment covering its many aspects. In the present investigation, an arylhydrazone derivative of 5-methoxyindole-2-carboxylic acid (5MeO), with in vitro strong antioxidant, neuroprotective and monoamine oxidase B-inhibiting effects, was studied in a scopolamine-induced Alzheimer-type dementia in rats. Using behavioral and biochemical methods, we evaluated the effects of 5MeO on learning and memory, and elucidated the mechanisms of these effects. Our experiments demonstrated that 5MeO had a beneficial effect on different types of memory as assessed by the step-through and the Barnes maze tasks. It efficiently restored the decreased by scopolamine brain-derived neurotrophic factor and acetylcholine levels and normalized the increased by scopolamine acetylcholine esterase activity in hippocampus. Most effective 5MeO was in counteracting the induced by scopolamine oxidative stress by decreasing the increased by scopolamine levels of lipid peroxidation and by increasing the reduced by scopolamine catalase activity. Blood biochemical analyses demonstrated a favorable safety profile of 5MeO, prompting further pharmacological studies suggesting 5MeO as a safe and efficient candidate in a multitargeted treatment of AD.

Examples of how metalloproteins feature in electron transfer processes in biological systems are reviewed. Attention is focused on the electron transport chains of cellular respiration and photosynthesis, and on metalloproteins that directly couple electron transfer to a chemical reaction. Brief mention is also made of extracellular electron transport. While covering highlights of the recent and the current literature, this review is aimed primarily at introducing the senior undergraduate and the novice postgraduate student to this important aspect of bioinorganic chemistry.

Cipangopaludina chinensis, as a financially significant species in China, represents a gastropod in nature which frequently encounters starvation stress owing to its limited prey options. However, the underlying response mechanisms to combat starvation have not been investigated in depth. We collected C. chinensis under several times of starvation stress (0, 7, 30, and 60 days) for nutrient, biochemical characteristics and transcriptome analyses. The results showed that prolonged starvation stress (> 30 days) caused obvious fluctuations in the nutrient composition of snails, with dramatic reductions in body weight, survival and digestive enzyme activity (amylase, protease, and lipase), and markedly enhanced the antioxidant enzyme activities of the snails. Comparative transcriptome analyses revealed 3538 differentially expressed genes (DEGs), which were significantly associated with specific starvation stress-responsive pathways, including oxidative phosphorylation and alanine, aspartate, and glutamate metabolism. Then, we identified 40 candidate genes (e.g., HACD2, Cp1, CYP1A2, and GPX1) response to starvation stress through STEM and WGCNA analyses. RT-qPCR verified the accuracy and reliability of the high-throughput sequencing results. This study provides insights into snail overwintering survival and the potential regulatory mechanisms of snail adaptation to starvation stress.

The underexplored halophilic genus Joostella within the Flavobacteriaceae family consists of only two species, both of which have received little attention for their potential biotechnological applications. In this study, we report the isolation and characterisation of a novel halophilic bacterium, strain CR20, using a genomic approach to investigate its biotechnological potential. Analysis of the 16S rRNA gene revealed that strain CR20 shares 97.5% and 96.2% sequence similarity with Joostella marina DSM 19592 T and Joostella atrarenae M1-2 T, respectively. Strain CR20 exhibited average nucleotide identity and digital DNA-DNA hybridisation values of 76.8-79.1% and 20.8-22.8%, respectively, with Joostella spp., which fall below the species delineation thresholds. Additionally, strain CR20 demonstrated average amino acid identity and percentage of conserved proteins values of 81.3-84.0% and 71.7-75.3%, respectively, with Joostella spp., above the genus delineation thresholds. Meanwhile, the average amino acid identity and percentage of conserved proteins values of strain CR20 against Galbibacter spp. are 73.9-80.0% and 61.3-72.3%, respectively, also above the genus delineation thresholds. These findings indicated strain CR20 has a close relationship with both genera. Chemotaxonomic analysis of strain CR20 identified predominant fatty acids, including iso-C17:0 3OH (25.3%), iso-C15:0 (14%), and C16:1 ω6c/C16:1 ω7c (12.2%). The assembled genome comprises 62 contigs, with a size of approximately 3,168,727 bp and a G + C content of 35.1%. Among 2,804 predicted genes, 2,559 were classified into 25 COG functional groups. A total of 68 genes with potential industrial applications were identified, including 1 β-mannanase, 2 β-xylosidases, 1 polysaccharide deacetylase, 4 other hemicellulases, 6 β-glucosidases, 25 proteases, and 29 phosphate-solubilising enzymes. Hydrolytic assays confirmed that strain CR20 produces these enzymes extracellularly. These findings highlight strain CR20 has potential for industrial applications.

Fluoxetine (FLX) is a Selective Serotonin Re-uptake Inhibitor (SSRI) commonly used as a first-line treatment for depression, anxiety, and mood disorders. It can cause infertility in the male reproductive system through the release of Reactive Oxygen Species (ROS). This study aimed to evaluate the testiculo-protective potential of ascorbic acid against fluoxetine-induced spermatotoxicity in male Wistar rats.

This study assessed Vitamin C's effect on male fertility in fluoxetine-treated Wistar rats. Thirty rats (130 ± 40 g) were divided into six groups (n=5): Control (distilled water), fluoxetine 20 mg/kg, Vitamin C 100 mg/kg, fluoxetine 20 mg/kg + Vitamin C 50 mg/kg, fluoxetine 20 mg/kg + Vitamin C 100 mg/kg, and fluoxetine 20 mg/kg + Vitamin C 150 mg/kg. Treatments were administered daily via oral gavage for 60 days, followed by assessments of testicular weight, semen analysis, oxidative stress biomarkers (CAT and GPx), and histomorphology. The data was analyzed using one-way ANOVA and Turkey's post-hoc multiple comparison test, reporting as mean±SEM using The GraphPad Prism version 6.0 for Windows, with significance set at p<0.05.

Vitamin C, administered particularly at higher doses, significantly increased body weight, testicular weight, and antioxidant enzyme levels (glutathione peroxidase and catalase) while improving fertility parameters such as sperm count, motility, and viability in treated rats (P<0.05). Fluoxetine alone led to a significant reduction (P<0.05) in these parameters, but the combination with Vitamin C mitigated these effects. Histological analysis showed improved testicular structure in Vitamin C-treated groups, highlighting its protective role against fluoxetine-induced testicular damage.

Ascorbic acid has testiculoprotective potential in fluoxetine-induced spermatotoxicity, mainly owing to its antioxidant properties.

Catalase, an enzyme central to maintaining redox balance and combating oxidative stress in plants, has emerged as a key player in plant defense mechanisms and interactions with microbes. This review article provides a comprehensive analysis of catalase-associated immune responses in plant-microbe interactions. It underscores the importance of catalase in plant defense mechanisms, highlights its influence on plant susceptibility to pathogens, and discusses its implications for understanding plant immunity and host-microbe dynamics. This review contributes to the growing body of knowledge on catalase-mediated immune responses and offers insights that can aid in the development of strategies for improved plant health and disease resistance.

The reaction of [M(L)]n with H2O2 as an [O2] unit source and NEt3 as a base is a widely used biomimetic transition metal-peroxo and -superoxo complex [M(L)O2]n-1 synthesis method, but the mechanism and accurate stoichiometry of the synthesis remain elusive. In this study, we performed DFT calculations to deeply understand the mechanism, using the synthesis of the cobalt-peroxo complex [CoIII(12-TMC)O2]+ (12-TMC = (1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane)) from the reaction of [CoII(12-TMC)]2+ and H2O2 in the presence of NEt3 as an example. The study found that cobalt-peroxo complex formation proceeds via three stages: (Stage I) the conversion of [CoII(12-TMC)]2+ and H2O2 to [CoIII(12-TMC)OH]2+ and OOH˙ radical, (Stage II) the coordination of OOH˙ to [CoII(12-TMC)]2+ to give [CoIII(12-TMC)OOH]2+, followed by deprotonation with NEt3, affording [CoIII(12-TMC)O2]+, and (Stage III) the transformation of [CoIII(12-TMC)OH]2+ which is generated in Stage I to [CoIII(12-TMC)O2]+. The overall stoichiometry of the synthesis is 2*[Co(12-TMC)]2+ + 3*H2O2 + 2*NEt3 → 2*[Co(12-TMC)O2]+ + 2*HNEt3+ + 2*H2O. In addition, compared to its analog [CoIII(TBDAP)O2]+ (TBDAP = N,N-di-tert-butyl-2,11-diaza[3.3](2,6)-pyridinophane) which is synthesized by the same method and has the same Co(III) oxidation state exhibits dioxygenase-like reactivity to nitriles, [CoIII(12-TMC)O2]+ could be inactive towards acetonitrile because the reaction severely deteriorates the coordination of the 12-TMC ligand to the Co center, which results in high reaction barriers.

The aim of the study was to investigate the effect of baicalin and baicalin-bovine serum albumin nanoparticles against bendiocarb exposure in rats.

Eighty male Wistar Albino rats aged 4-6 weeks were used. Corn oil (vehicle) alone was administered to the control group. To other groups, BSA-nanoparticle equivalent to that binding baicalin at a dose of 20 mg/kg.bw, 20 mg/kg.bw baicalin, baicalin-BSA nanoparticle equivalent to that binding baicalin at a dose of 20 mg/kg.bw, 4 mg/kg.bw bendiocarb, combination of 4 mg/kg.bw bendiocarb and 20 mg/kg.bw baicalin, combination of 4 mg/kg.bw bendiocarb and BSA-nanoparticle equivalent to that binding baicalin at a dose of 20 mg/kg.bw and combination of 4 mg/kg.bw bendiocarb and baicalin-BSA nanoparticle equivalent to that binding baicalin at a dose of 20 mg/kg.bw was administered to animals by oral gavage with vehicle for 21 days, after which organs (liver, kidney, brain, testes, heart and lung) and blood samples were collected. Blood/tissue oxidative stress (MDA, NO, GSH, SOD, CAT, GSH-Px, GR, GST, G6PD), serum biochemical (glucose, triglyceride, cholesterol, BUN, creatinine, uric acid, total protein, albumin, LDH, AST, ALT, ALP and pseudocholinesterase) and liver and kidney apoptotic/anti-apoptotic (caspase 3, 9, p53, Bcl-2 and Bax) parameters were evaluated. Body weights/organ weights and plasma/liver bendiocarb analyses were obtained.

While bendiocarb administered alone caused oxidative stress/tissue damage, baicalin and baicalin-BSA nanoparticle showed a mitigating effect. However, this effect was more pronounced in the baicalin-BSA nanoparticle group. BSA-nanoparticle alone did not have a significant effect in reversing the adverse effect caused by bendiocarb.

The study aims to compare the action of Pleurotus cornucopiae and glibenclamide on alloxan-induced diabetes and ascertain how an aqueous extract of the edible mushroom regulates the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), oxidative stress biomarkers and renal toxicity in a diabetic male Wistar rat model. Twenty-five adult male Wistar rats were randomly grouped into five groups with five rats per. Group 1 and those in the treatment groups received normal feed and water ad libitum. Group 2 received intraperitoneal administration of alloxan monohydrate (150 mg/kg body weight). Group 3 received alloxan monohydrate and glibenclamide (5 mg/kg body weight bwt), group 4 received alloxan monohydrate plus the extract (250 mg/kg bwt) and group 5 received alloxan monohydrate plus the extract (500 mg/kg bwt). The administration of glibenclamide plus the extract was oral for 14 days. Glibenclamide and the extract lowered blood glucose level, catalase, and glutathione peroxidase activities, increased the superoxide dismutase (SOD) activity in rats with alloxan induced diabetes. The extract at 500 mg/kg bwt reduced the plasma urea and sodium concentration in the treated rats. The extract and glibenclamide could detoxify alloxan and restore its induced renal degeneration and glomeruli atrophy, intra renal hemorrhage and inflammation and oxidative biomarkers through activation of Nrf2 expression. The drug glibenclamide and P. cornucopiae have appreciable hypoglycemic activity and potential to restore the normal renal architecture in the rats, hence they offer similar curative effects. Additionally, the extract at 500 mg/kg bwt activated SOD and Nrf2 expression more than glibenclamide in rats with alloxan-induced diabetes.

Microglia are primarily involved in inflammatory reactions and oxidative stress in the brain; as such reducing microglial activation has been proposed as a potential therapeutic strategy for neurodegenerative disorders. Herein, we investigated the anti-inflammatory and antioxidant activities of coniferaldehyde (CFA), a naturally occurring cinnamaldehyde derivative, on activated microglia to evaluate its therapeutic potential. CFA inhibited the production of nitric oxide (NO) and proinflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-1β, and IL-6, in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. CFA also inhibited intracellular reactive oxygen species levels and oxidative stress markers such as 4-HNE and 8-OHdG. Detailed mechanistic studies showed that CFA exerted anti-inflammatory effects by inhibiting TAK1-mediated MAP kinase/NF-κB activation and upregulating AMPK signaling pathways. In addition, CFA exerted antioxidant effects by inhibiting the NADPH oxidase subunits and by increasing the expression of antioxidant enzymes such as HO-1, NQO1, and catalase by upregulating Nrf2 signaling. Finally, we confirmed the effects of CFA on the brains of the LPS-injected mice. CFA inhibited microglial activation and the expression of proinflammatory markers and increased Nrf2-driven antioxidant enzymes. Furthermore, CFA inhibited the production of 4-HNE and 8-OHdG in the brains of LPS-injected mice. As a result, CFA's significant anti-inflammatory and antioxidant properties may have therapeutic applications in neuroinflammatory disorders related with oxidative stress and microglial activation.

Lithium is a critical mineral in a wide range of current technologies, and demand continues to grow with the transition to a green economy. Current lithium mining and extraction practices are often highly ecologically damaging, in part due to the large amount of water and energy they consume. Biomineralization is a natural process that transforms inorganic precursors to minerals. Microbial biomineralization has potential as an ecofriendly alternative to current lithium extraction techniques. This work demonstrates Lysinibacillus sphaericus biomineralization of lithium chloride to lithium hydroxide. Quantitative analysis of biomineralized lithium via the 2-(2-hydroxyphenyl)-benzoxazole fluorescence assay reveals significantly greater recovery with L. sphaericus than without. Furthermore, L. sphaericus biomineralization is specific to lithium over sodium. The nanoparticles produced were further characterized via Fourier transform infrared and transmission electron microscopy analysis as crystalline lithium hydroxide, which is an advanced functional material. Finally, ESI-LC/MS was used to identify several proteins involved in this microbial biomineralization process, including the S-layer protein. Through the isolation of L. sphaericus ghosts, this work shows that the S-layer protein alone plays a critical role in the biomineralization of crystalline lithium hydroxide nanoparticles. Through this study of microbial biomineralization of lithium with L. sphaericus, there is potential to develop innovative and environmentally friendly extraction techniques.

This study aimed to evaluate biomarkers of oxidative stress (2-thiobarbituric acid reactive substances, aldehyde and ketone derivatives of oxidatively modified proteins and total antioxidant capacity), the activity of antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase), that of lysosomal enzymes (alanyl aminopeptidase, leucyl aminopeptidase, β-N-acetylglucosaminidase and acid phosphatase) and changes in biochemical parameters (alanine aminotransferase, aspartate aminotransferase, de Ritis ratio, lactate dehydrogenase activity, lactate and pyruvate levels and their ratio) in the liver tissue of fish that were vaccinated against enteric redmouth disease and challenged with its causative agent, the bacterium Yersinia ruckeri.

The vaccine was administered orally to trout, some of which were challenged with Y. ruckeri 61 days later. For comparison, unvaccinated and unchallenged trout and unvaccinated and challenged trout were also evaluated.

In the unvaccinated fish, infection with Y. ruckeri disrupted the pro-oxidant/antioxidant balance, led to a significant increase in lipid peroxidation and oxidative modification of proteins, decreased total antioxidant capacity and significantly increased the activity of lysosomal enzymes. In vaccinated fish, the Y. ruckeri challenge increased the activity of glutathione-related enzymes and decreased lipid peroxidation, anaerobic metabolism and the activity of lysosomal enzymes in fish livers relative to the unvaccinated and challenged group. In contrast, these parameters increased after the Y. ruckeri challenge in unvaccinated trout relative to those in the untreated group.

Vaccination exerted a protective effect during the Y. ruckeri challenge and had no adverse effect on fish livers.

Catalase (CAT), a ubiquitous enzyme in all oxygen-exposed organisms, effectively decomposes hydrogen peroxide (H2O2), a harmful by-product, into water and oxygen, mitigating oxidative stress and cellular damage, safeguarding cellular organelles and tissues. Therefore, CAT plays a crucial role in maintaining cellular homeostasis and function. Owing to its pivotal role, CAT has garnered considerable interest. However, many challenges arise when used, especially in multiple practical processes. "Immobilization", a widely-used technique, can help improve enzyme properties. CAT immobilization offers numerous advantages, including enhanced stability, reusability, and facilitated downstream processing. This review presents a comprehensive overview of CAT immobilization. It starts with discussing various immobilization mechanisms, support materials, advantages, drawbacks, and factors influencing the performance of immobilized CAT. Moreover, the review explores the application of the immobilized CAT in various industries and its prospects, highlighting its essential role in diverse fields and stimulating further research and investigation. Furthermore, the review highlights some of the world's leading companies in the field of the CAT industry and their substantial potential for economic contribution. This review aims to serve as a discerning, source of information for researchers seeking a comprehensive cutting-edge overview of this rapidly evolving field and have been overwhelmed by the size of publications.

BACKGROUND Neonatal hypoxic-ischemic encephalopathy (HIE) is a significant cause of perinatal and postnatal morbidity and mortality worldwide. Catalase (CAT) activity detection is used to determine levels of inflammation and oxidative stress. Glutathione (GSH) is the most critical non-enzymatic endogenous antioxidant. Lipid peroxidation levels marked after hypoxia can be detected based on the level of malondialdehyde (MDA). Ischemia-modified albumin (IMA) is considered a biomarker for cardiac ischemia and is known to increase in the liver, brain, and kidney in states of insufficient oxygenation. We aimed to explain the results and relations between the oxidant and antioxidants to detail oxidant-antioxidant balance and cellular mechanisms. MATERIAL AND METHODS Serum levels of IMA and MDA, as an oxidative stress marker, and CAT and GSH, as antioxidant enzymes, were measured in first blood samples of 59 neonates diagnosed with HIE, with pH <7, base excess >12, and APGAR scores. RESULTS Neonates who were ≥37 weeks of gestation and had hypoxia were included. Compared with healthy newborns (n=32), CAT was statistically significantly lower in the hypoxia group (P=0.0001), while MDA serum levels were significantly higher in neonates with hypoxia (P=0.01). There was no difference between hypoxic and healthy neonates in GSH and IMA measurements (P=0.054, P=0.19 respectively). CONCLUSIONS HIE pathophysiology involves oxidative stress and mitochondrial energy production failure. Explaining the pathways between oxidant-antioxidant balance and cell death, which explains the pathophysiology of HIE, is essential to develop treatment strategies that will minimize the effects of oxygen deprivation on other body organs, especially the brain.

We report the discovery that the molecule 1-(pyridin-2-ylmethylamino)propan-2-ol (HL) can reduce oxidative stress in neuronal C6 glioma cells exposed to reactive oxygen species (O2-•, H2O2, and •OH) and metal (Cu+) stress conditions. Furthermore, its association with Cu2+ generates [Cu(HL)Cl2] (1) and [Cu(HL)2](ClO4)2 (2) complexes that also exhibit antioxidant properties. Potentiometric titration data show that HL can coordinate to Cu2+ in 1:1 and 1:2 Cu2+:ligand ratios, which was confirmed by monocrystal X-ray studies. The subsequent ultraviolet-visible, electrospray ionization mass spectrometry, and electron paramagnetic resonance experiments show that they can decompose a variety of reactive oxygen species (ROS). Kinetic studies revealed that 1 and 2 mimic the superoxide dismutase and catalase activities. Complex 1 promotes the fastest decomposition of H2O2 (kobs = 2.32 × 107 M-1 s-1), efficiently dismutases the superoxide anion (kcat = 3.08 × 107 M-1 s-1), and scavenges the hydroxyl radical (RSA50 = 25.7 × 10-6 M). Density functional theory calculations support the formation of dinuclear Cu-peroxide and mononuclear Cu-superoxide species in the reactions of [Cu(HL)Cl2] with H2O2 and O2•-, respectively. Furthermore, both 1 and 2 also reduce the oxidative stress of neuronal glioma C6 cells exposed to different ROS, including O2•- and •OH.

We have characterized the catalytic cycle of the Helicobacter pylori KatA catalase (HPC). H. pylori is a human and animal pathogen responsible for gastrointestinal infections. Multifrequency (9-285 GHz) EPR spectroscopy was applied to identify the high-valent intermediates (5 ≤ pH ≤ 8.5). The broad (2000 G) 9-GHz EPR spectrum consistent with the [Fe(IV) = O Por•+] intermediate was detected, and showed a clear pH dependence on the exchange-coupling of the radical (delocalized over the porphyrin moiety) due to the magnetic interaction with the ferryl iron. In addition, Trp• (for pH ≤ 6) and Tyr• (for 5 ≤ pH ≤ 8.5) species were distinguished by the advantageous resolution of their g-values in the 285-GHz EPR spectrum. The unequivocal identification of the high-valent intermediates in HPC by their distinct EPR spectra allowed us to address their reactivity towards substrates. The stabilization of an [Fe(IV) = O Trp•] species in HPC, unprecedented in monofunctional catalases and possibly involved in the oxidation of formate to the formyloxyl radical at pH ≤ 6, is reminiscent of intermediates previously identified in the catalytic cycle of bifunctional catalase-peroxidases. The 2e- oxidation of formate by the [Fe(IV) = O Por•+] species, both at basic and acidic pH conditions, involving a 1H+/2e- oxidation in a cytochrome P450 peroxygenase-like reaction is proposed. Our findings demonstrate that moonlighting by the H. pylori catalase includes formate oxidation, an enzymatic reaction possibly related to the unique strategy of the neutrophile bacterium for gastric colonization, that is the release of CO2 to regulate the pH in the acidic environment.

In the current study, two commercial industrial hemp (IH) fiber varieties (V1: CFX-2 and V2: Henola) were assessed for their ability to regulate salt-induced oxidative stress metabolism. For 30 days, plants were cultivated in greenhouse environments with five different salinity treatments (0, 50, 80, 100, 150, and 200 mM NaCl). Hydrogen peroxide (H2O2), malondialdehyde (MDA), and lipoxygenase (LOX) and antioxidant enzymes (superoxide dismutase (SOD), catalase, guaiacol peroxidase (GPOD), ascorbate peroxidase (APX), glutathione reductase (GR), and glutathione-S-transferase (GST)) were assessed in fully expanded leaves. At 200 and 100 mM NaCl concentrations, respectively, 30 days after saline treatment, plants in V1 and V2 did not survive. At 80 mM NaCl, the leaves of V2 showed higher concentrations of H2O2, MDA, and LOX than those of V1. Higher SOD, CAT, GPOD, APX, GR, and GST activity in the leaves of V1 up to 100 mM NaCl resulted in lower levels of H2O2 and MDA. At 80 mM NaCl, V2 demonstrated the total failure of the antioxidant defense mechanism. These results reveal that V1 demonstrated stronger salt tolerance than V2, in part due to better antioxidant metabolism.

Difenoconazole-loaded (CS-DIF) microcapsules were synthesized by encapsulating difenoconazole into biocompatible chitosan. The physical and chemical properties indicated that the encapsulation and chemical loading rates were 85.58% and 61.98%, respectively. The microcapsules exhibited prominent controlled-release and surface stability performance. The cumulative release rate was only 33.6% in 168 h, and the contact angle decreased by 11.73° at 120 s compared with difenoconazole. The antifungal activity of the CS-DIF microcapsules against Curvularia lunata was confirmed through observations of colony growth, in vitro and in vivo inoculation, mycelium morphology, as well as DNA and protein leakage. The antioxidant enzyme activity of superoxide dismutase, peroxidase, and catalase decreased by 65.1%, 84.9%, and 69.7%, respectively, when Curvularia lunata was treated with 200 μg/mL microcapsules, compared with the control in 24 h. The enzymatic activity of polyphenol oxidase decreased by 323.8%. The reactive oxygen species contents of hydrogen peroxide and superoxide anions increased by 204.6% and 164%, respectively. Additionally, the soluble sugar and soluble protein contents decreased by 65.5% and 69.6%, respectively. These findings provided a novel approach to control the growth of C. lunata efficiently, laying a foundation for reducing the quantity and enhancing the efficiency of chemical pesticides. The CS-DIF microcapsules exhibited a strong inhibitory effect on fungus, effectively preventing and controlling leaf spot disease and showing potential for field applications. This study might be of great significance in ensuring plant protection strategies.

Treatment of the most aggressive and deadliest form of skin cancer, the malignant melanoma, still has room for improvement. Its invasive nature and ability to rapidly metastasize and to develop resistance to standard treatment often result in a poor prognosis. While the highly effective standard chemotherapeutic agent doxorubicin (DOX) is widely used in a variety of cancers, systemic side effects still limit therapy. Especially, DOX-induced cardiotoxicity remains a big challenge. In contrast, the natural chalcone cardamonin (CD) has been shown to selectively kill tumor cells. Besides its anti-tumor activity, CD exhibits anti-oxidative, anti-inflammatory and anti-bacterial properties. In this study, we investigated the effect of the combinational treatment of DOX with CD on A375 melanoma cells compared to normal human dermal fibroblasts (NHDF) and rat cardiac myoblasts (H9C2 cells). DOX-induced cytotoxicity was unselective and affected all cell types, especially H9C2 cardiac myoblasts, demonstrating its cardiotoxic effect. In contrast, CD only decreased the cell viability of A375 melanoma cells, without harming normal (healthy) cells. The addition of CD selectively protected human dermal fibroblasts and rat cardiac myoblasts from DOX-induced cytotoxicity. While no apoptosis was induced by the combinational treatment in normal (healthy) cells, an apoptosis-mediated cytotoxicity was demonstrated in A375 melanoma cells. CD exhibited thiol reactivity as it was able to directly interact with N-acetylcysteine (NAC) in a cell-free assay and to induce heme oxygenase-1 (HO-1) in all cell types. And that took place in a reactive oxygen species (ROS)-independent manner. DOX decreased the mitochondrial membrane potential (Δψm) in all cell types, whereas CD selectively decreased mitochondrial respiration, affecting basal respiration, maximal respiration, spare respiratory capacity and ATP production in A375 melanoma cells, but not in healthy cardiac myoblasts. The DOX-induced cytotoxicity seen in melanoma cells was ROS-independent, whereas the cytotoxic effect of CD was associated with CD-induced ROS-formation and/or its thiol reactivity. This study highlights the beneficial properties of the addition of CD to DOX treatment, which might protect patients from DOX-induced cardiotoxicity. Future experiments with other tumor cell lines or a mouse model should substantiate this hypothesis.