H2O2 Peroxidation Research Articles

Energy-Efficient Geopolymer Composites Containing Phase-Change Materials-Comparison of Different Contents and Types.

The purpose of this study was to analyze the effects of phase-change components on the properties of geopolymer foams. Geopolymer foams are lightweight foamed geopolymers that are characterized by a high degree of porosity. Phase change materials, on the other hand, are compounds that, when added to a material, allow it to absorb, store, and then release large amounts of energy. Three types of PCMs, i.e., MikroCaps, GR42, and PX25, were introduced at 15% by weight. Geopolymer materials were produced based on silica fly ash, and hydrogen peroxide H2O2 was used to foam the geopolymer structure. The PCM geopolymer composites were cured at 60 °C. The produced materials were tested for physical, chemical, and thermal properties. The tests included oxide and mineral composition analysis of the base material, PCM particle size analysis, apparent density and porosity tests on the foams, water leachability tests, thermal tests (λ, Cv, Cp, α), and structural and textural analysis. The most relevant tests to confirm the performance of the phase-change materials were thermal tests. With the introduction of PCMs, volumetric heat capacity increased by as much as 41% and specific heat by 45%, and thermal diffusivity decreased by 23%. The results confirm the great potential of geopolymer composites as modern insulation materials for buildings and structures.

Consideration of fuel and oxidizer combinations for mass and volume limited hybrid rocket motors

AbstractThis research considers different storable oxidizer and fuel combinations for hybrid propulsion, looking for the most adequate candidates for mass and volume limited systems. High specific impulse Isp is the main indication for minimum mass, whereas high density specific impulse ρIsp is a good measure for smaller volume. Other aspects such as safety, handling, toxicity, burn rate, hypergolicity, and the oxidizer to fuel O/F ratio, may affect the final choice of propellant ingredient combination. For mass‐limited systems hydrogen peroxide H2O2 or nitrogen tetroxide N2O4 (the latter is toxic and hard to handle) oxidizers give the best results with most solid fuels (mainly hydroxyl‐terminated polybutadiene HTPB). For volume‐limited systems the same combinations may apply; however, in that case polyester fuel may be an adequate choice as well because of its high density. Nitrous oxide N2O is the most inadequate oxidizer for volume‐limited systems, yielding ρIsp lower by about 40 % compared to other oxidizers. Reducing the structure and insulation mass may result from decreasing the high‐pressure, high‐temperature section (the combustion chamber) and can be achieved from high O/F combinations employing N2O or H2O2 oxidizers. N2O gives relatively safe system, H2O2 enables hypergolic combinations, HNO3 is good for long‐term storage, whereas paraffin wax and expandable graphite additive yield high fuel regression rate and thrust. Overall, H2O2 oxidizer seems optimal for many operational aspects, but it should be chemically stabilized to minimize decomposition.

Synthesis of CoMnFe2O4 hollow microstructure decorated GO for photocatalytic degradation of organic dyes

Over the past decade, safeguarding marine life and aquatic ecosystems against deleterious dye pollutants has emerged as a paramount concern. Methylene blue dye stands out as one such pollutant capable of inflicting irreversible damage to marine ecosystems even at minute concentrations. Addressing this pressing issue, we synthesized a novel CoMnFe2O4/graphene oxide nanocomposite employing a microwave-ultrasonic method. This composite, comprising soft superparamagnetic CoMnFe2O4 hollow microstructures integrated onto graphene oxide surfaces, revealed a mesoporous structure with a notably high surface area, which was about 96.4654 m2.g−1. Various analytical techniques were employed to scrutinize the crystal structure, functional groups, surface chemical composition, and morphologies of the synthesized CoMnFe2O4/graphene oxide nanocomposite (X-ray diffraction, Fourier-Transform Infrared Spectroscopy, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy, and high-resolution transmission electron microscopy). The CoMnFe2O4 crystal phase appears to be cubic in the X-ray diffraction with a 28.91 nm Avg. crystallite size. The measured band gap energies for the CoMnFe2O4, graphene oxide, and CoMnFe2O4/graphene oxide nanocomposite are 2.23 eV, 2.90 eV, and 1.89 eV, respectively. Remarkably, under visible light irradiation, the nanocomposite exhibited an impressive degradation efficiency of 97.54 % within just fifty minutes (at pH = 7, Methylene blue conc. = 15 mg/L, and catalyst dose = 0.05 g.), attributed to a photo degradation rate constant (k value) reaching 0.07330 min−1. Notably, this efficiency nearly doubled with the introduction of H2O2 peroxide. The outstanding recyclability of the CoMnFe2O4/graphene oxide nanocomposite, sustaining optimal performance over four cycles without significant degradation, underscores its potential for long-term environmental remediation efforts. Moreover, its magnetic extractability from contaminated solutions enhances its suitability for advanced environmental applications.

The salinity impact on changes in some metabolites and some vital subcellular organelles in white maize

BackgroundThe great need to propagate new crop genotypes that are well adapted to the changing environmental conditions is urgently needed to support the high demand of food of the growing world population. In this work five white maize inbred lines (P4, P8, P12, P15, and P17) were studied for their salinity tolerance when exposed to: 0, 1000, 2000, 3000, and 10000 mg/L NaCl. The equilibrium balance between reactive oxygen species ROS and the detoxification cascades points to the plant’s performance under stress. The free amino acid and soluble sugar contents (non-enzymatic antioxidants) in addition to the superoxide dismutase & Phenylalanine ammonia-lyase SOD& PAL (enzymatic antioxidants) and some phenolic compounds contents were evaluated against hydrogen peroxide H2O2 as ROS product to classify plants to stress -tolerance or sensitive. Transmission electronic microscope (TEM) investigation is also, used to study the impact of the stress on the plant cells’ compartments after the direct treatment with saline water for 3 h as moderate soil holding time capacity to irrigation water.ResultsMaize line P8 followed by line P17 were the highest to cope with the irrigation of saline water in different ranges of concentrations of salt, accumulate the soluble sugars, free amino acids and antioxidants over control and other maize lines. These results are supported by the root ultrastructure observation with transmission electronic microscope.ConclusionMaize line P8 followed by the P17 line are highly recommended to be crossed and planted in the newly reclaimed lands irrigated with salty water.Graphical

Preventive effect of an ethanolic avocado on apoptosis induced via oxidative damage in albino rats tissues

Oxidative stress is the result of an imbalance between the production of oxidant precursors and the capacity of antioxidant defense. Oxygen free radicals play an important role in causing diseases. In this study, the protective effect of ethanolic avocado on apoptosis caused by oxidative damage in the tissue of albino rats was investigated. 24 male albino rats of the Faculty of Veterinary Medicine in Mosul, Iraq, which were kept in standard conditions for at least 10 days before and through the experimental work, were examined. Four groups of rats include the control group (healthy group), the group of male rats with ethanolic avocado consumption; The third group of male rats that were treated with 0.5% of hydrogen peroxide H2O2; and the fourth group of male rats that were treated with both 0.5% H2O2 and avocado ethanolic extract (50 mg kg-1 BW) for four weeks. After fixing the tissues of the liver, kidney, lung, spleen and testis in 10% buffered formalin, they were stained with hematoxylin. TUNEL assay was performed using the TUNEL cell death assay kit to detect apoptotic cells. In this investigation, the histology results in four groups of rats showed that in the rats that were treated with avocado, there were minor tissue changes in their liver, kidney, and intestine, and the tissues of these organs were healthy. In TUNEL staining, it was also shown that there are no apoptotic cells in the liver, kidney and testis cells in avocado-treated rats. The results showed that ethanolic Avocado is useful against oxidative stress damage and it may be used to protect tissues against oxidative stress.

Efficacy of endophytic bacteria as promising inducers for enhancing the immune responses in tomato plants and managing Rhizoctonia root-rot disease

Around the world, a variety of crops, including tomatoes, suffer serious economic losses due to the Rhizoctonia root-rot disease. Herein, Bacillus velezensis, Bacillus megaterium, and Herpaspirillum huttiense isolated from strawberry (Fragaria chiloensis var. ananassa) plants were pragmatic as plant growth promotors for battling the Rhizoctonia root rot disease and bringing about defense mechanisms as well as growth promotional strategies in tomato plants. These endophytic bacteria demonstrated potent antifungal activity against R. solani in vitro along in vivo. Data explained that the isolated endophytic bacteria could produce Indole acetic acid, Gibberellic acid GA, and siderophore as well as solubilize phosphate in the soil. The consortium of (Bacillus velezensis, Bacillus megaterium, and Herpaspirillum huttiense) increased the protection % against Rhizoctonia infection by (79.4%), followed by B. velezensis by (73.52%), H. huttiense by (70.5%), and B. megaterium by (67.64%), respectively. There was an increase in soluble proteins and carbohydrates in infected plants treated with a consortium of endophytic bacteria by 30.7% and 100.2% over untreated infected plants, respectively. Applying endophytic bacteria either alone or in combination lowered the level of malondialdehyde MDA and hydrogen peroxide H2O2 and improved the activities of antioxidant enzymes in both infected and uninfected plants. Also, bacterial endophytes have distinctive reactions regarding the number and concentrations of isozymes in both infected and uninfected plants. It could be recommended the commercial usage of a mixture of targeted bacterial endophyte strains as therapeutic nutrients against Rhizoctonia root-rot disease as well as plant growth inducer.

RADIOCARBON STEP-COMBUSTION OXIDATION METHOD AND FTIR ANALYSIS OF TRONDHEIM CaCO3 PRECIPITATES OF ATMOSPHERIC CO2 SAMPLES: FURTHER INVESTIGATIONS AND INSIGHTS

ABSTRACT Eight atmospheric carbon dioxide samples (as calcium carbonate—CaCO3—precipitates) from Lindesnes site (58ºN, 7ºE), belonging to 1963 and 1980 (four samples from each year) and stored at the National Laboratory for Age Determination (NTNU), have been reevaluated through radiocarbon (14C) analysis. Previous 14C results indicated the presence of a contaminant, which was not removed through different chemical cleansing procedures (e.g., hydrochloric acid—HCl and/or hydrogen peroxide—H2O2). Here, we present a follow up investigation using 14C step-combustion and Fourier-transform infrared spectroscopy (FTIR) analysis. Results from 14C data indicate unsuccessful removal of the contaminant, while further FTIR analysis displayed the presence of moisture. This finding alludes to the possibility that the contaminant is of ambient air-CO2 deeply embedded in CaCO3 powders (within clogged CaCO3 pores and/or bonded to the lattice). Samples were found exposed to air-CO2 and humidity. These conditions may have lasted for years, possibly even decades, leading to the 14C offsets detected here.

Selective flotation separation of molybdenite and talc by yeast infusion with H2O2 peroxidation

Molybdenum is an important alloy element for metallurgical industry. As the major mineral reserve for molybdenum, molybdenite (MoS2) is commonly associated with talc. The flotation separation of talc and molybdenite is challenging due to their excellent inherent floatability. In this study, we innovatively used oxidant and inhibitor to perform reverse flotation of molybdenite and yeast infusion was evaluated as a potential depressant in the reverse flotation separation of molybdenite from talc. Flotation tests of single mineral samples and multi-mineral samples were carried out to evaluate the performance of yeast infusion and H2O2 in flotation. And the results show that under the 100 mg/L H2O2, 100 mg/L yeast infusion treated molybdenite can be effectively separated from talc, the grade and recovery of Mo in the sink product were 42.8% and 80%. Contact angle measurement, X-ray photoelectron spectroscopy and zeta potential data indicated that the surface of molybdenite underwent slight oxidation after H2O2 treatment. The hydrophilicity of molybdenite was also significantly enhanced. Results of infrared spectroscopy and adsorption tests demonstrated that H2O2 enhanced yeast infusion adsorption on molybdenite.

Variation of PAI-1 and oxidant-antioxidant status in Four Human Cancers

Objective: The present study was disigned to invistigate the effect of plasmin-plasminogen system variable which is plasminogen activator inhibitor-1 (PAI-1) on the occurrence of the development of malignant and benign tumors. In addition to illustrate the oxidative stress effect on the malignant and benign tumors occuring and complication progress. Which involving Glutathione Peroxidase (GPx) and Hydrogen Peroxide H2O2. On the other hand, current study amied to nominate the most suitable variant as an effective tumor marker

Morphological and Optical Modification of Melanosomes in Fish Integuments upon Oxidation

Reactive oxygen species (ROS) such as superoxide radicals O2−, hydroxyl radicals OH−, and hydrogen peroxide H2O2 may have detrimental effects on marine organisms, including their integuments and visual appearances. Although some studies have described the impact of ROS on marine ecosystems and species ecology, the influence on the optical response of the integuments of marine species and on their visual appearances remains unknown. In this article, we used histology and optical characterisation to show, for the first time, that skin melanophores (melanin-containing chromophores) of the coral reef fish, Stegastes apicalis, change their shapes and fluorescent proprieties upon oxidation with H2O2 radicals. Our observations also suggest that pheomelanosomes may occur in fish integuments, where, previously, it was thought that fish melanosomes only contain eumelanin. This investigation relied on light and electron microscopy and steady-state fluorimetry, as well as time-resolved streak imaging systems. We suggest that the changes in the morphological and spectral characteristics of melanophores can be used as a marker of physiological stress induced by environmental factors such as ROS. Moreover, S. apicalis may be used as a potential model for studying the interaction between the surrounding environment and natural organisms in biologically diverse ecosystems, such as the Great Barrier Reef in Australia.

A Mitochondrial-targeted curcumin-based fluorescent probe for real-time tracking endogenous hydrogen peroxide in living cells

To explore high-performance fluorescent probes that endow tunability and capability for in vivo analysis is an enduring goal of visualizing and manipulating biological events. Hydrogen peroxide H2O2, as a central redox signaling molecule, is the tough hurdle to real-time in situ tracking dynamic subcellular H2O2. Herein, we present a curcuminoid difluoroboron based fluorescent probe DFB-1 which contains the triphenylphosphine (TPP) moiety as mitochondrial targeting unit and aryl boronates as the specific uncaging group. Notably, this activatable probe DFB-1 bestows several striking characteristics: (i) dual-channel fluorescence response with a large shift; (ii) active mitochondria-targeting; (iii) light-up NIR fluorescence with high signal-to-background ratio. The probe DFB-1 is successfully employed in sensing endogenous H2O2 with a limit of detection 0.025 μM, and effectively differentiate H2O2 fluctuation between hepatocellular carcinoma and colorectal cancer cells. This dual-channel NIR probe DFB-1 realizes new advances in deep insight into the function of mitochondrial endogenous H2O2.

Comparative study of the carnitine, Gensing, Dill, and Arginine effect in sperm of normal and experimentally H2O2 induced oxidative stres albino male rats

The aim of this study is to compare the effects of Carnitine, Gensing, Dill and Arginine in characteristics of the sperms:total sperm, percentage of live and dead sperm, normal and abnormal sperm in male normal and exposuedrats to oxidative stress induced by hydrogen peroxide H2O2(0.5%) in drinking water during the experiment for 30 days. Fifty male rats used in age 12-14 weeks in weights (300-325g) divided randomly into 10 groups, included 5 in each group as following. 
 Control, H2O2 , Carnitine , carnitine + H2O2 , Gensing , Gensing + H2O2, Dill, Dill+ H2O2, Arginine, Arginine + H2O2 groups.
 Results showed:
 1- Treating normal rats with Carnitine, Gensing , Dill, Arginine, led to a significant increase in value(P≤0.05) in Total sperm, percentage of live sperm, and a significant decrease in dead sperm and no difference in normal and abnormal sperm percentage comparing to control group.
 2- Oxidative stress Induced by H2O2 led to significant increase in value (P≤ 0.05) in percentage of abnormal sperm comparing to control group. While there were a significant decrease in value (P≤0.05) in Total sperm, percentage of live and normal sperm.
 3- Treating rats exposure to oxidative stress with Carnitine, Gensing, Dill, Arginine, led to a significant decrease in value (P≤0.05) in percentage of abnormal and dead sperm, While the treating led to significant increase in Total sperm, percentage of live and normal sperm.

Methylcyclopropene treatment retards the yellowing in pak choi (Brassica rapa subsp. Chinensis) through modulating the programmed cell death during storage at 20°C

The deterioration of post-harvest quality in plants has been shown to be connected with the occurrence of programmed cell death (PCD). Our previous research indicated that 5 μL L−1 1-Methylcyclopropene (1-MCP) delays the yellowing of post-harvest pak choi leaves. However, whether 1-MCP alleviates pak choi yellowing through regulating PCD process, and the regulatory mechanism of 1-MCP on PCD are still unclear. Results showed that 5 μL L−1 1-MCP could retard the PCD process of pak choi as proved by the maintenance of lower cytochrome C content and caspase-3 activity. The results of cell mortality and trypan blue staining further confirmed this view. Forty-five differentially expressed genes (DEGs) involving PCD of pak choi were identified in the transcriptome data. The treatment suppressed the over-accumulation of reactive oxygen species (ROS) (superoxide anion O2·− and hydrogen peroxide H2O2), lipid membrane oxidation, ethylene production, and expression of their related genes (BcRBOHC, BcRBOHD, BcLOX1/3/5, BcACO, BcACO4 and BcEIN3)) during senescence. This relationship was also connected to the preservation of higher level in antioxidant capacity of antioxidase and antioxidants (ascorbate-glutathione (AsA-GSH)), as well as high expression of their related genes (BcSOD, BcAPX, and BcGR) in 1-MCP-treated pak choi. Moreover, 1-MCP down-regulated the transcript of genes involved in PCD, regulated the expression of genes associated with mitochondrial membrane transport, respiration and signaling, and chloroplast membrane transport and REDOX, thereby contributing to the inhibition of PCD. The correlation analysis revealed that pak choi yellowing was positively related with the process of PCD. Taken together, the present study indicated that 1-MCP could delay the yellowing of pak choi through mitigating PCD process, involving the regulation of ROS metabolism, membrane lipid degradation, antioxidant status and ethylene production.

Comparative study of the carnitine, Gensing, Dill, and Arginine effect in MDA, SOD, GSH levels in albino rats exposued to oxidative stress.

The aim of this study is to compare the effects of Carnitine, Gensing, Dill and Arginine in lipid peroxidation MDA and SOD, GSH antioxidant in normal and experimentally hydrogen peroxide H2O2 induced oxidative.
 Fifty male rats used in age 12-14 weeks in weights (300-325 g) divided randomly into 10 groups, included 5 in each group as following.
 Control, H2O2 , Carnitine , carnitine + H2O2 , Gensing , Gensing + H2O2 , Dill, Dill+ H2O2 ,Arginine , Arginine + H2O2 groups.
 Results showed:
 1-Treating normal rats with Carnitine, Gensing, Dill, Arginine, led to a significant increase (P≤0.05) in GSH level in all groups except Gensing group, and a significant decrease in MDA level in all groups except Carnitine group and no difference in SOD comparing to control group.
 2-Oxidative stress Induced by H2O2 led to significant increase in value (P≤ 0.05) in levels of MDA, comparing to control group. While there were a significant decrease in value (P≤0.05) in GSH, SOD.
 3-Treating rats exposure to oxidative stress with Carnitine, Gensing, Dill, Arginine, led to a significant decrease in value(P≤0.05) in MDA, While the treatment led to significant increase in GSH, , SOD comparing with H2O2 group.

Effect of Acarbose and olive leaf extract (Oleuropein) on Glycemic index and Antioxidant Status in High Fructose and H2O2 Exposed Rats (Parts-II)

This study was carried out to investigate the effect of acarbose or combination of acarbose and Oleuropein (OLEU) on glycemic index and antioxidant status of male rats exposed to high fructose(40%) and 0.05% hydrogen peroxide H2O2 Thirty-two adult male rats were randomly divided into four equal groups: control group (CC); T1( HFr-H2O2) group were exposed to high fructose (40%) in drinking water and given orally 0.05% H2O2; T2: 30mg/kg of acarbose were given orally to HF-H2O2 treated rats, while combination of acarbose and Oleuropein (50mg/kg. B.W) were given orally to (HFr-H2O2) treated rats in group T3. Blood samples were taken at zero time and after two months of the experiment for measuring some parameters related to glycemic index and antioxidant status. The results declared an elevation in the glycemic index (insulin and glucose concentrations and insulin resistance (IR)) and malondialdehyde (MDA) and depression in glutathione (GSH) concentrations in T1 group at the end of experiment comparing to other treated groups. Antioxidant status and glycemic index were restored after acarbose or combination of acarbose and Oleuropein treatment characterized by significant depression of serum glucose, insulin concentrations and IR, and alleviation of oxidative stress clarified by depression of serum MDA with elevation in serum GSH concentration in groups T2 and T3. On conclusion, the current study documented the oxidative and hyperglycemic effect of fructose and H2O2 that can be ameliorating by oral administration of acarbose. Besides, combination of OLUE supplement with acarbose possessed additive effects.

Exogenous melatonin ameliorates yellowing of postharvest pak choi (Brassica rapa subsp. chinensis) by modulating chlorophyll catabolism and antioxidant system during storage at 20 °C

The objective of this study was to investigate the regulatory mechanism of melatonin (MT) treatment on leaf yellowing of pak choi during storage at 20 °C. Results showed that 500 μmoL L−1 MT alleviated the yellowing process of pak choi as proved by the maintenance of high level of leaf colour, chlorophyll content and chlorophyll fluorescence parameters (Fo, Fm and Fv/Fm), and the market life of pak choi was extended by 2 d compared to the control. The weight loss and respiration rate were effectively alleviated by MT treatment. MT treatment restrained chlorophyll breakdown by down-regulating the activity of chlorophyll-degrading enzymes (chlorophyllase CLH, pheophytinase PPH and Mg-dechelatase MDS) and expression of their related genes (BcCLH, BcPPH1/2, BcSGR, BcHCAR, BcNYC1 and BcCAO). Meanwhile, MT suppressed the over-accumulation of reactive oxygen species (ROS) (superoxide anion O2·− and hydrogen peroxide H2O2), and lipid membrane oxidation and associated gene (BcLOX) expression during senescence, thus helping to keep green colour of pak choi. This relationship was also connected to the maintenance of higher level in antioxidant ability of antioxidase (superoxide dismutase SOD, ascorbate peroxidase APX, peroxidase POD and catalase CAT) and antioxidants (ascorbate-glutathione (AsA-GSH)), as well as high expression of their related genes (BcSOD, BcPOD, BcCAT, BcGPX and BcAPX) in pak choi treated with MT. In conclusion, these findings suggested that MT could delay the yellowing of pak choi, involving the regulation of chlorophyll metabolism, ROS metabolism, membrane lipid degradation, and antioxidant capacity. The results provide a possible target for delaying the yellowing of green vegetables.

Analysis of the level of oxidative stress by assessing the damage to the plasma protein serum albumin under the influence of an oxidizing agent

Oxidative stress, which leads to oxidative modification of various macromolecules, including proteins, is now considered an important pathogenetic link in many diseases. In this work, oxidative damage to a blood plasma protein, bovine serum albumin BSA, under the action of an oxidizing agent, hydrogen peroxide H2O2, was studied by spectrofluorometric method. The H2O2 concentration-dependent quenching of the intrinsic fluorescence of BSA is shown. BSA fluorescence quenching constants in hydrogen peroxide solutions are calculated by mathematical modeling methods. The dependences found in the fluorescence quenching constants are explained both by oxidative damage to the microenvironment of BSA tryptophan residues and by changes in the native conformation of protein globules upon oxidative damage. More significant peroxide damage to BSA occurs at lower pH values due to the fact that H2O2, as an oxidizing agent, acts more strongly in an acidic environment. The registered quenching of the protein's own fluorescence when damaged by an oxidizing agent can be used as a medical method for assessing the level of oxidative stress in the body in the diagnosis of a number of diseases.

Heavy Metals, Halogenated Hydrocarbons, Phthalates, Glyphosate, Cordycepin, Alcohol, Drugs, and Herbs, Assessed for Liver Injury and Mechanistic Steps.

Aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, mercury, nickel, thallium, titanium, zinc, carbon tetrachloride, phthalates, glyphosate, alcohol, drugs, and herbs are under discussion having the potential to injure the human liver, but allocation of the injury to the hepatotoxicant as exact cause is difficult for physicians and requires basic clinical knowledge of toxicology details. Liver injury occurs at a variable extent depending on the dose, mostly reproducible in animal models that allow studies on molecular steps leading to the hepatocellular injury. These exogenous hepatotoxins may cause an overproduction of reactive oxidative species (ROS), which are generated during microsomal or mitochondrial oxidative stress from incomplete oxygen split and trigger the injury if protective antioxidant capacities are reduced. Primary subcelluar target organelles involved are liver mitochondria through lipid peroxidation of membrane structures and the action of free radicals such as singlet radical 1O2, superoxide radical HO•2, hydrogen peroxide H2O2, hydroxyl radical HO•, alkoxyl radical RO•, and peroxyl radical ROO•. They attempt covalent binding to macromolecular structural proteins. As opposed to inorganic chemicals, liver injury due to chemicals with an organic structure proceedes via the hepatic microsomal cytochrome P450 with its different isoforms. In sum, many exogenous chemicals may have the potential of liver injury triggerd by overproduced ROS leading primarily to impairment of mitochondial functions in the course of structural mitochondial membrane dearrangement. As clinical data were often incomplete, future clinical prototols should focus on meeting liver injury criteria, exclusion of alternative causes, a robust causality evaluation management, and obtaining liver histology if clinically indicated and of benefit for the patient.

Treatment of Contaminated Textile Factories’ Wastewater by Photocatalyst Degradation

The aim of this work is remove the textile factories’ wastewater such as dyes via the Advanced Oxidation Processes (AOPs) that on using the nano titanium dioxide photocatalytic degradation. The degradation of C. I. Reactive black 45 (RB 45) in aqueous medium by the photocatalysis process has been studied. The effects of several parameters such as pH, the concentration of TiO2, irradiation time, and dye concentration have been examined. The optimal parameters were found to be [TiO2] = 0.75 g/L, irradiation time 480 min and pH=3.0. The results shown that the photocatalytic degradation could be enhanced by adding hydrogen peroxide H2O2 or potassium persulfate K2S2O8, for example, the efficiency increased from 68.9% to 88.7% and 95.4% when added 0.027 M or 1.5 g/L of H2O2 and K2S2O8 respectively. Also, the effects of inorganic salts Na2SO4, Na2CO3, and NaCl on the degradation efficiency of the photocatalysis process were investigated.

A Study of Anxiety-Related Behavior under Conditions of Oxidative Stress Caused by Hydrogen Peroxide

Any stressful situation in the body can become the cause of intense formation of free radicals. Free radicals are molecules or individual atoms that have unpaired valence electrons in their outer orbit, which are characterized by high reactivity and damage cell proteins, nucleic acids, membrane lipids, and can lead to the development of many types of pathological processes. All possible triggering mechanisms of this process have not been fully explored. It is known that under certain conditions, in response to stressogenic factors, a biologically positive reaction _ adaptive stress response develops in the body which ensures the resistance of cells to stronger (lethal) doses of the stimulating agent of this reaction. The aim of the study was to explore the influence of the hormetic phenomenon on the psycho-emotional state of anxiety which arose from the dose-response of the oxidative stress caused by hydrogen peroxide in an experiment on rats. The experiment was conducted on white male lab rats. As an experimental model of oxidative stress caused by hydrogen peroxide, we used its 0.1% and 0.2% aqueous solutions and administered them orally to animals for different durations (10 and 25 days). The psycho-emotional state of anxiety was assayed by means of the elevated plus maze. The analysis of the obtained results was conducted using the student's t-criterion.The analysis of our results allows us to note that in the experiment under the conditions of chronic action of a low dose of stressogenic factor (hydrogen peroxide H2O2  0.1%), an improvement in the psycho-emotional state of anxiety and its stable maintenance within the maximum limits of the norm can be observed, which must be caused by the influence of the hormetic response. A further increase (doubling of the "dose") of the stressogenic factor (chronic administration of 0.2% aqueous solution of hydrogen peroxide) resulted in suppression of the hormesis. It was found that in this experimental model, oxidative stress can play a positive role in the regulation of neuroplasticity and psycho-physiological adaptation.