H2O2 Injection Research Articles

Oxidative stress causes liver injury via the damage of redox system and the apoptosis induced by mitochondria of broiler

The aim of this study was conducted to explore the effects of oxidative stress on the redox system, mitochondrial function, and apoptosis in liver of broilers. 144 one-day-old male Ross-308 broilers from the same batch had been prepared in advance and were divided into 3 treatments: normal control group (without intraperitoneal injection), normal saline group (intraperitoneal injection of normal saline), and hydrogen peroxide (H2O2) group (intraperitoneal injection of H2O2) with 6 replicates of 8 chickens each. The experimental period was 42 days. The injection volumes were 1.0 mL/kg of Ross-308 broiler body weight. On the 42nd day of the experimental period, two Ross-308 broilers were randomly selected from each cage, a total of 36 broilers were stunned by electric shock and slaughtered to collect liver samples. The results showed that compared with the non-injection group and the injection of saline group, H2O2 exposure elevated the relative weight of liver and the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum of Ross-308 broilers (p < 0.05). Meanwhile, compared with the non-injection group and the injection of saline group, the H2O2 exposure increased the levels of reactive oxygen species (ROS), MDA, lipid peroxide (LPO) and protein carbonyl, decreased the activities of total superoxide dismutase (T-SOD), catalase (CAT), total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-Px) (p < 0.05). Compared with the non-injection group and the injection of saline group, the H2O2 exposure caused microvesicular steatosis and mitochondrial vacuolisation in the liver tissues of broilers. Additionally, after H2O2 exposure, the levels of nuclear factor erythroid 2–related factor 2 (Nrf2) positive cells were reduced and the relative percentage of hepatocyte apoptosis were increased in the liver tissues of broilers (p < 0.05). The conclusion of this study is that the oxidative stress induced by intraperitoneal injection of H2O2 could induce excessive production of ROS in broiler liver, which damage the antioxidant status and mitochondrial function of liver cells, leading to cell apoptosis. HIGHLIGHTS Oxidative stress can cause severe damage to the liver of broilers. Oxidative stress can mainly damage liver antioxidant function Oxidative stress can induce cell apoptosis by damaging mitochondria in the liver of broilers

Emission Onset Time-Adjustable Chemiluminescent Gold Nanoparticles with Ultrastrong Emission for Smartphone-Based Immunoassay of Severe Acute Respiratory Syndrome Coronavirus 2 Antigen.

Recently, our group reported a chemical timer approach to manipulate the onset time of chemiluminescence (CL) emission. However, it is still in the proof-of-concept stage, and its analytical applications have not been explored yet. Nanomaterials have merits of good catalytic effect, large specific surface area, good biocompatibility, and ease of self-assembly, which are ideal for constructing analytical-interfaces for bioassays. Herein, an emission onset time-adjustable chemiluminescent L012-Au/Mn2+ was synthesized for the first time by modifying Mn2+ on the surface of L012-protected gold nanoparticle. By using H2O2 and NaHCO3 as coreactants, L012-Au/Mn2+ could not only generate an ultrastrong and long-time CL emission but also its CL emission onset time could be adjusted by the addition of thiourea, which could effectively eliminate interference from the addition of coreactants, shorten the exposure time, reduce the detection background, and finally achieve high sensitivity CL imaging analysis. On this basis, a label-free CL immunoassay was constructed with a smartphone-based imaging system for high-throughput and sensitive determination of severe acute respiratory syndrome coronavirus 2 nucleocapsid (N) protein. The CL image of the immunoassay with different concentrations of N proteins was captured in one photograph 100 s after the injection of H2O2 with a short exposure time of 0.5 s. The immunoassay showed good linearity over the concentration range of 1 pg/mL to 10 ng/mL with a detection limit of 0.13 pg/mL, which was much lower than the reported CCD imaging detection method. In addition, it showed good selectivity and stability and was successfully applied in serum samples from healthy individuals and COVID-19 rehabilitation patients.

Combination therapy with hydrogen peroxide and irradiation promotes an abscopal effect in mouse models.

Hydrogen peroxide (H2 O2 ) induces oxidative stress and cytotoxicity, and can be used for treating cancers in combination with radiotherapy. A product comprising H2 O2 and sodium hyaluronate has been developed as a radiosensitizer. However, the effects of H2 O2 on antitumor immunity remain unclear. To investigate the effects of H2 O2 , especially the abscopal effect when combined with radiotherapy (RT), we implanted murine tumor cells simultaneously in two locations in mouse models: the hind limb and back. H2 O2 mixed with sodium hyaluronate was injected intratumorally, followed by irradiation only at the hind limb lesion. No treatment was administered to the back lesion. The H2 O2 /RT combination significantly reduced tumor growth at the noninjected/nonirradiated site in the back lesion, whereas H2 O2 or RT individually did not reduce tumor growth. Flow cytometric analyses of the tumor-draining lymph nodes in the injected/irradiated areas showed that the number of dendritic cells increased significantly with maturation in the H2 O2 /RT combination group. In addition, analyses of tumor-infiltrating lymphocytes showed that the number of CD8+ (cluster of differentiation 8) T cells and the frequency of IFN-γ+ (interferon gamma) CD8+ T cells were higher in the noninjected/nonirradiated tumors in the H2 O2 /RT group compared to those in the other groups. PD-1 (programmed death receptor 1)blockade further increased the antitumor effect against noninjected/nonirradiated tumors in the H2 O2 /RT group. Intratumoral injection of H2 O2 combined with RT therefore induces an abscopal effect by activating antitumor immunity, which can be further enhanced by PD-1 blockade. These findings promote the development of H2 O2 /RT therapy combined with cancer immunotherapies, even for advanced cancers.

Enhanced accumulation of bitumen residue in a highly concentrated tailings flow by microbubbles from in-situ catalytic decomposition of hydrogen peroxide

The massive volume of oil sands tailings has been one of the most challenging environmental issues. In this work, we experimentally explore a simple and effective approach to bitumen residue separation from a highly concentrated slurry flow of the artificial oil sands tailings. By utilizing microbubbles from in-situ catalytic decomposition of H2O2 at low concentrations, bitumen aggregation is enhanced on the top part of the hydrotransport pipeline. The microscopic image analysis revealed the in-situ formation of microbubbles and confirmed that magnetic particles present in the slurries contributed to the fast release of the gas products and bubble formation from hydrogen peroxide decomposition. A high-speed camera was applied to capture images of the tailings flow in the pipeline through a transparent view window. A large number of tiny bubbles were identified post to the injection of H2O2 to the slurry flow. More than 70 % bitumen could be recovered from a lab-scale pipeline loop within 30 mins after H2O2 injection. The bitumen recovery efficiency from the collected froth was quantitatively compared under seven conditions with varied dosages, the concentration of H2O2, and the amount of magnetic solids in the slurries. Our results confirmed that the total dosage of H2O2 is the dominant factor in in-situ microbubble formation for enhanced bitumen aggregation in the flow. Importantly, microbubbles were generated rapidly in the real mature fine tailings. The results from our study provide insights into the preferential distribution of oil residue in the flow during hydrotransport without the requirement for an additional device. Removal of oily residues from concentrated slurries may bring economical and environmental advantages.

Dietary curcumin supplementation relieves hydrogen peroxide-induced testicular injury by antioxidant and anti-apoptotic effects in roosters

This study was aimed to investigate the effects of dietary curcumin supplementation on the hydrogen peroxide (H2O2)-induced testicular oxidative damage in breeder roosters. Thirty-two 20-week roosters were randomly divided into four groups: (1) basal diet (CON); (2) basal diet with H2O2 challenge (H2O2); (3) basal diet with 200 mg/kg curcumin (CUR); (4) basal diet with 200 mg/kg curcumin and H2O2 challenge (CUR + H2O2). The trial lasted for 8 weeks, H2O2 challenged groups got an intraperitoneal injection of H2O2 at the 50 and 53 days, while the CON and CUR groups received an injection of saline. The results showed that dietary curcumin supplementation significantly decreased abnormal sperm rates in the semen, notably improved seminiferous tubules, increased testis scores, and serum testosterone levels. Curcumin supplementation could also ameliorate the redox damage caused by H2O2, by enhancing the capacities of antioxidant enzymes (CAT, GSH-Px, SOD, and T-AOC), and reducing MDA levels. In addition, curcumin normalized the H2O2-induced negative effects, which included downregulations in spermatogenesis-related genes (STAR, HSD3-β1, SYCP3, AKT1) and antioxidant genes (HMOX-1, NQO-1), reduced protein expressions of Nrf2, PCNA, and Bcl-2, and increased protein expressions of Caspase 3 and Bax. Moreover, H2O2-induced decreased mRNA expressions of EIF2AK3, Caspase3, and BCL-2 were all reversed by dietary curcumin supplementation. In summary, dietary curcumin supplementation could relieve H2O2-induced oxidative damage and reproduction decline through the Nrf2 signaling pathway and anti-apoptotic effects in roosters.

Antibacterial Applications of Low-Pressure Plasma on Degradation of Multidrug Resistant V. cholera

The existence of Vibrio cholera (V. cholera) is a major health problem in many parts of the world; therefore, the treatments of V. cholera have always remained necessary for public safety, health, and environmental protection. In the last few decades, plasma discharges have proven to be a novel technique of sterilization against infectious bacteria such as V. cholera. In this research, a low-pressure plasma (LPP) technique has been introduced for the degradation of multidrug resistant V. cholera. The V. cholera strains with 107 CFUs (colony-forming units) were treated by low-pressure plasma, with and without H2O2 injection into the sterilization chamber, to investigate and report the adverse effects of plasma on V. cholera. The results demonstrated that plasma treatment has significant effects on the degradation of V. cholera in the presence of H2O2 vapors inside the plasma sterilization chamber. The time-course study of the bactericidal effects revealed that there is no regeneration or increase in the number of V. cholera colonies after plasma treatment.

Novel and highly stable strategy for the development of microfluidic enzymatic assays based on the immobilization of horseradish peroxidase (HRP) into cotton threads

The use of biological components in the development of new methods of analysis and point-of-care (POC) devices is an ever-expanding theme in analytical chemistry research, due to the immense potential for early diagnosis of diseases and monitoring of biomarkers. In the present work, the evaluation of an electrochemical microfluidic device based on the immobilization of horseradish peroxidase (HRP) enzyme into chemically treated cotton threads is described. This bioreactor was used as a channel for the build of the microfluidic device, which has allowed to use of a non-modified screen-printed electrode (SPE) as an amperometric detector. Cotton threads were treated using citric acid, and the immobilization of HRP has been performed by EDC/NHS crosslinking, connecting amine groups of the enzymes to carboxylic acids in the cellulosic structure. For the analytical evaluation, an amperometric assay for hydrogen peroxide detection was performed after the injection of H2O2 and hydroquinone (HQN) concomitantly. The enzymatic reaction consumes H2O2 leading to the formation of O-quinone, which is readily reducible at non-modified SPE. Several experimental parameters related to enzyme immobilization have been investigated and under the best set of conditions, a good analytical performance was obtained. In addition, the threads were freezer-stored and, after 12 weeks, 84% of hydrogen peroxide sensitivity was maintained, which is very reasonable for enzyme-based systems and still offers good analytical precision. Therefore, a simple and inexpensive microfluidic system was reported by crosslinking carboxylic groups to amine-containing macromolecules, suggesting a new platform for many other protein-based assays.

Taurine inhibits hydrogen peroxide-induced oxidative stress, inflammatory response and apoptosis in liver of Monopterus albus

Fish are extremely vulnerable to environmental stimulation and produce oxidative stress. Among them, hydrogen peroxide is an oxidative stress source that cannot be ignored in fish, which can cause physical disorders, inflammation and even death. Taurine was revealed to reduce oxidative damage and inflammation caused by toxic substances, but whether it can reduce toxicity of rice field eel caused by H2O2 has not been determined. Thus, the intervention effects of taurine on H2O2-induced oxidative stress, inflammation, apoptosis, and autophagy in rice field eel. The results showed that oxidative injury in the liver was determined after H2O2 injection, as indicated by enhanced serum AST and ALT activities, inhibited the antioxidant function (increased MDA and ROS contents, decreased antioxidant enzymes, inhibited nrf2 transcription level), and induced inflammatory response (upregulated il-1β, il-6, il-8, and il-12β gene expression, downregulated tgf-β1 gene expression, activated the transcription level of nf-κb, tlr-3, and tlr-7). In addition, bax, caspase3, beclin1, and Lc3B gene expression were significantly upregulated after H2O2 injection, while bcl2 and p62 gene expression were downregulated, leading to the occurrence of apoptosis and autophagy. In contrast, adding 0.2 and 0.5% taurine to feed significantly alleviated this damage, as indicated by the recovery of the aforementioned bioindicators, and the effect of 0.5% taurine addition is better than 0.2%. Overall, these results suggested that taurine can relieve the liver toxicity induced by H2O2, which enriched the toxic mechanism of H2O2 on fish and provided evidence for the protective effect of taurine on liver.

Factors influencing hydrogen peroxide decomposition dynamics for thermochemical treatment of bottomhole zone

Recently, interest in on-site heat generation has increased due to injection of thermochemical fluids as a complex effect on well productivity. The method of thermochemical treatment with H2O2 while restoring and increasing the filtration characteristics of the bottomhole formation zone is a relatively new and insufficiently studied technology. The article discusses the key factors affecting the exothermic decomposition of this fluid when this fluid is injected into the well. The heat effects, pressure growth and decomposition time of H2O2 were determined depending on the salinity of the water, the composition of terrigenous rock, and various concentrations of H2O2. Physical 1-D modeling of H2O2 injection was carried out on rock models with mobile and stationary oil, which demonstrated a sharp increase in temperature by 100–240 °C caused by the decomposition of H2O2 due to the catalyst and the presence of catalytic active sites in the rock. As a result of this thermochemical treatment, the rock was partially cleaned of immobile oil and heavy sediments. Injection of H2O2 with a catalyst has shown the effectiveness of displacement of mobile oil from the filled sand model. Thus, the results of this study can provide a preliminary assessment of the effectiveness of H2O2 thermochemical treatment in fields operated at a later stage of development.

Sanguinarine attenuates hydrogen peroxide-induced toxicity in liver of Monopterus albus: Role of oxidative stress, inflammation and apoptosis

In aquatic animals, hydrogen peroxide (H2O2), which is a source of oxidative stress, can cause physiological dysfunction, inflammation, and death. Sanguinarine (SAN) is a plant extract known to improve antioxidant and immune capacity. However, the roles of SAN in H2O2-induced liver tissue toxicity is unclear. The effects on hepatic oxidative damage, inflammatory response, and apoptosis were investigated by feeding rice field eel with 0, 375, and 750 μg/kg of SAN for eight weeks and then intraperitoneally injected with H2O2. The results showed that after 24 h of H2O2 injection, the activities of ALT and AST in serum were significantly increased, oxidative damage and inflammatory response occurred in the liver, and apoptosis was induced, which indicated that H2O2 induced liver damage in rice field eel. However, dietary supplemented with 375 or 750 μg/kg SAN significantly decreased the activities of ALT and AST in serum, and significantly increased the antioxidant function (decreased ROS, MDA, and antioxidant enzymes levels, downregulated antioxidant-related gene expression, and inhibited the transcription level of nrf2). The addition of SAN at 375 or 750 μg/kg ameliorated H2O2-induced inflammatory response of liver (upregulated tgf-β1 mRNA expression, downregulated il-1β, il-6, il-8, and il-12β mRNA expression, and inhibited the transcription levels of tlr-3 tlr-7, and nf-κb). In addition, dietary supplemented with 375 or 750 μg/kg SAN alleviated the apoptosis of liver induced by H2O2 (downregulated bax mRNA expression, upregulated caspase3 mRNA expression, and reduced the number of apoptotic cells by TUNEL staining). Overall, these results suggested that SAN could alleviate the liver injury in rice field eel induced by H2O2, mainly by improving antioxidant capacity, alleviating inflammatory response and inhibiting apoptosis, and the effect of 750 μg/kg SAN addition is better than 375 μg/kg.

A heat shock protein protects against oxidative stress induced by lambda-cyhalothrin in the green peach aphid Myzus persicae

Lambda-cyhalothrin (LCT) is a pyrethroid insecticide widely used to control insect pests. Insect exposure to LCT may cause abnormal accumulation of reactive oxygen species (ROS) and result in oxidative damage. Heat shock proteins (HSPs) may help protect against oxidative stress. However, little is known about the role of HSPs in response to LCT in the green peach aphid, Myzus persicae. This insect is an important agricultural pest causing severe yield losses in crops. In this study, we characterized a cDNA sequence (MpHsp70) encoding a member of the HSP70 family in M. persicae. MpHsp70 encoded a 623 amino acid protein putatively localized in the cytosol. The highest expression level of MpHsp70 occurred in fourth-instar nymphs. Treatment of M. persicae with LCT resulted in oxidative stress and significantly increased H2O2 and malondialdehyde levels. This led to an elevated transcription level of MpHsp70. Injection of H2O2 into M. persicae also upregulated the MpHsp70 expression level, suggesting that MpHsp70 is responsive to ROS, particularly H2O2, induced by LCT. Recombinant MpHSP70 protein was expressed in Escherichia coli. E. coli cells overexpressing MpHSP70 exhibited significant tolerance to H2O2 and the ROS generators, cumene hydroperoxide and paraquat. This indicated that MpHSP70 protects against oxidative stress. Furthermore, knockdown of MpHsp70 by RNA interference resulted in increased susceptibility in apterous adults of M. persicae to LCT. These findings indicate that MpHsp70 plays an important role in defense against LCT-induced oxidative stress and insecticide susceptibility in M. persicae.

Fe(III)-Complex-Imprinted Polymers for the Green Oxidative Degradation of the Methyl Orange Dye Pollutant.

One of the biggest problems worldwide is the pollution of natural water bodies by dyes coming from effluents used in the textile industry. In the quest for novel effluent treatment alternatives, the aim of this work was to immobilize Fe(III) complexes in molecularly imprinted polymers (MIPs) to produce efficient Fenton-like heterogeneous catalysts for the green oxidative degradation of the methyl orange (MO) dye pollutant. Different metal complexes bearing commercial and low-cost ligands were assayed and their catalytic activity levels towards the discoloration of MO by H2O2 were assessed. The best candidates were Fe(III)-BMPA (BMPA = di-(2-picolyl)amine) and Fe(III)-NTP (NTP = 3,3′,3″-nitrilotripropionic acid), displaying above 70% MO degradation in 3 h. Fe(III)-BMPA caused the oxidative degradation through two first-order stages, related to the formation of BMPA-Fe-OOH and the generation of reactive oxygen species. Only the first of these stages was detected for Fe(III)-NTP. Both complexes were then employed to imprint catalytic cavities into MIPs. The polymers showed catalytic profiles that were highly dependent on the crosslinking agent employed, with N,N-methylenebisacrylamide (MBAA) being the crosslinker that rendered polymers with optimal oxidative performance (>95% conversion). The obtained ion-imprinted polymers constitute cheap and robust solid matrices, with the potential to be coupled to dye-containing effluent treatment systems with synchronous H2O2 injection.

A tubular ceramic membrane coated with TiO2-P25 for radial addition of H2O2 towards AMX removal from synthetic solutions and secondary urban wastewater.

This work aims to integrate several hydrogen peroxide (H2O2) activation mechanisms, photolysis (UVC irradiation), chemical electron transfer (TiO2-P25 photocatalysis), and reaction with TiO2-P25 in dark conditions, for reactive oxygen species (ROS) generation towards the removal of contaminants of emerging concern (CECs), in a single unit operated in continuous-flow mode. An H2O2 stock solution is fed by the lumen side of a tubular ceramic membrane, delivering the oxidant to the (i) catalyst immobilized in the membrane shell-side and (ii) annular reaction zone (ARZ, space between membrane shell-side and outer quartz tube) where CECs contaminated water flows with a helix trajectory, being activated by UV light provided by four lamps placed symmetrically around the reactor. First, the effect of several parameters in the removal of a CEC target molecule, amoxicillin (AMX), was evaluated using a synthetic solution ([AMX]inlet = 2.0 mg L-1): (i) light source (UVA or UVC radiation), (ii) H2O2 dose, (iii) H2O2 injection method (radial permeation vs. upstream injection), and (iv) number of TiO2-P25 layers deposited on the membrane. The UVC/H2O2/TiO2 system with radial addition of H2O2 (20 mg L-1) and 9-TiO2-P25 layers provided the highest AMX removal efficiency (72.2 ± 0.5%) with a UV fluence of 45 mJ cm-2 (residence time of 4.6 s), due to the synergic effect of four mechanisms: (i) AMX photolysis, (ii) H2O2 photocleavage, (iii) TiO2-P25 photoactivation, and (iv) chemical reactions between H2O2 and TiO2-P25. The urban wastewater matrix showed a negative effect on AMX removal (~44%) due to the presence of ROS scavengers and light-filtering species.

Oxidative stress, DNA damage, and cellular response in hydrogen peroxide-induced cell injury of mud crab (Scylla paramamosain)

Oxidative stress is considered as the toxicity mechanism of environmental stressors on aquatic organisms. This study aims to explore the effects of oxidative stress on physiological responses, DNA damage and transcriptional profiles of the mud crabs Scylla paramamosain. In the present study, mud crabs were injected with 0.1% and 1% hydrogen peroxide (H2O2) for 72 h. The results showed that superoxide dismutase and catalase activities significantly decreased after H2O2 injection. Malondialdehyde content, H2O2 content, aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase activity significantly increased after H2O2 injection. Moreover, DNA damage occurred after H2O2 injection. Transcriptome analysis showed that 531 and 372 differentially expressed genes (DEGs) were identified after 0.1% and 1% H2O2 injection, respectively. These DEGs were mainly involved in the oxidative stress response and immune functions. All these results indicated that oxidative stress could impair both antioxidant defense systems and immune systems. Transcriptome analysis provided valuable information on gene functions associated with the response to oxidative stress in the mud crab.

تأثیر تمرین هوازی و مکملگیری ویتامین D بر میزان Fas و c-FLIP کبدی رتهای قرار گرفته در معرض آب اکسیژنه

Introduction: The aim of the present study was to investigate the effect of regular aerobic exercise and vitamin D supplementation on hepatic apoptosis in rats exposed to oxygenated water (H2O2). Methods: For this purpose, 60 adult male Wistar rats weighed 220±20 g were randomly divided into ten groups (n=6 in each group) including: control group (C), H2O2 (H), double H2O2 (2H), H2O2 + Vitamin D3 Supplement (HD), double H2O2 + Vitamin D3 Supplement (2HD), H2O2+ Exercise (HE), double H2O2+ Exercise (2HE), H2O2 + Vitamin D3 Supplement + Exercise (HDE), double H2O2 + Vitamin D3 + Exercise (2HDE) and Dimethyl Sulfoxide + Saline (DMSO). Then, the animals were exposed to oxidative stress (intraperitoneal injection of H2O2 3 times a week), vitamin D3 (intraperitoneal injection daily) and daily treadmill exercise for 8 weeks (duration of training sessions 30 to 60 min, at speeds of 8 to 20 m/min). The rats were sacrificed 24 hours after the last training session and liver tissue was extracted and Fas and c-FLIP protein concentration was measured by ELISA method. One-way ANOVA was used to compare the between groups differences. Results: The results showed that Fas protein levels were higher in the H, 2H, HD and 2HD groups compared to the control group (P<0.05) and of c-FLIP protein level was lower in the H and 2H groups compared to the control group (P<0.05). The 2HE and 2HDE groups also showed less Fas protein level compared to the 2H group (P<0.05). In addition, the HE group compared to the H group and 2HE and 2HDE groups compared to the 2H group showed higher levels of c-FLIP protein concentration (P<0.05). Conclusion: Overall, the results of the present study showed that exposure of rats to H2O2 initiates apoptotic cascade in liver tissue. However, regular treadmill exercise was able to attenuate this effect to a large extent, but vitamin D3 supplementation did not.

Effect of Physiological Concentrations of Vitamin C on the Inhibitation of Hydroxyl Radical Induced Light Emission from Fe2+-EGTA-H2O2 and Fe3+-EGTA-H2O2 Systems In Vitro.

Ascorbic acid (AA) has antioxidant properties. However, in the presence of Fe2+/Fe3+ ions and H2O2, it may behave as a pro-oxidant by accelerating and enhancing the formation of hydroxyl radicals (•OH). Therefore, in this study we evaluated the effect of AA at concentrations of 1 to 200 µmol/L on •OH-induced light emission (at a pH of 7.4 and temperature of 37 °C) from 92.6 µmol/L Fe2+—185.2 µmol/L EGTA (ethylene glycol-bis (β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid)—2.6 mmol/L H2O2, and 92.6 µmol/L Fe3+—185.2 µmol/L EGTA—2.6 mmol/L H2O2 systems. Dehydroascorbic acid (DHAA) at the same range of concentrations served as the reference compound. Light emission was measured with multitube luminometer (AutoLumat Plus LB 953) for 120 s after automatic injection of H2O2. AA at concentrations of 1 to 50 µmol/L and of 1 to 75 µmol/L completely inhibited light emission from Fe2+-EGTA-H2O2 and Fe3+-EGTA-H2O2, respectively. Concentrations of 100 and 200 µmol/L did not affect chemiluminescence of Fe3+-EGTA-H2O2 but tended to increase light emission from Fe2+-EGTA-H2O2. DHAA at concentrations of 1 to 100 µmol/L had no effect on chemiluminescence of both systems. These results indicate that AA at physiological concentrations exhibits strong antioxidant activity in the presence of chelated iron and H2O2.

Dietary taurine attenuates hydrogen peroxide-impaired growth performance and meat quality of broilers via modulating redox status and cell death signaling

Oxidative stress seriously affects poultry production. Nutritional manipulations have been effectively used to alleviate the negative effects caused by oxidative stress. This study investigated the attenuating effects and potential mechanisms of dietary taurine on the growth performance and meat quality of broiler chickens challenged with hydrogen peroxide (H2O2). Briefly, a total of 192 male Arbor Acres broilers (28 d old) were randomly categorized into three groups: non-injection of birds on basal diets (control), 10.0% H2O2 injection of birds on basal diets (H2O2), and 10.0% H2O2 injection of birds on basal diets supplemented with 5 g/kg taurine (H2O2 + taurine). Each group consisted of eight cages of eight birds per cage. Results indicated that H2O2 administration significantly reduced growth performance and impaired breast meat quality by decreasing ultimate pH and increasing shear force value (P < 0.05). Dietary taurine improved the body weight gain and feed intake and decreased feed/gain ratio of H2O2-challenged broilers. Meanwhile, oxidative stress induced by intraperitoneal injection of H2O2 suppressed the nuclear factor-κB (NF-κB) signaling and initiated autophagy and apoptosis. Compared with the H2O2 group, taurine supplementation restored the redox status in the breast muscle by decreasing levels of reactive oxygen species and contents of oxidative products and increasing antioxidant capacity (P < 0.05). Moreover, upregulated mRNA expression of NF-κB signaling-related genes, including NF-κB subunit 1 (p50) and B-cell CLL/lymphoma 2 (Bcl-2), and enhanced protein expression of NF-κB were observed in the H2O2 + taurine group (P < 0.05). Additionally, dietary taurine decreased the expression of caspase family, beclin1, and microtubule-associated protein 1light chain 3 beta (LC3-II; P < 0.05), thereby rescuing autophagy and apoptosis in breast muscle induced by H2O2. Collectively, dietary supplementation with taurine effectively improves growth performance and breast meat quality of broilers challenged with H2O2, possibly by protecting against oxidative injury and modulating cell death signaling.

A Study on the Comparative Analysis of 2-MIB Treatment Characteristics and Optimization of Process Operation in 2-types of Advanced Water Treatment Plants in the Han River Water Supply System

Objectives:In this study, through the results of the high-concentration 2-MIB (2-Methyl Isoborneol) treatment by two different types of advanced treatment plants (Post Peroxone+GAC, UV/H2O2+GAC F/A) which intake raw water from the same water intake facility, the 2-MIB removal characteristics by oxidation process of each WTPs (Water Treatment Plants) were compared and analyzed, and optimal operation methods were derived.Methods:The 2-MIB removal rate was compared and analyzed according to each AOP (Advanced Oxidation Process) operating conditions (Post Peroxone+GAC of the G WTP and UV/H2O2+GAC F/A of the I WTP). The optimal equations of chemical injection were derived through the correlation between the operating conditions of the AOP for each WTPs and 2-MIB removal rate. By analyzing the operating characteristics of each WTPs, the cost and unit price for optimal operation were calculated according to the 2-MIB concentration of raw water and water production. Optimal operating conditions were derived through the performance of oxidation facilities and chemical injection equations of each WTPs, and economical operating plans were reviewed through linked operation of 2 WTPs.Results and Discussion:The 2-MIB removal rates for each WTPs were 70~100% for the G WTP and 50~96% for the I WTP. The operating conditions affecting the 2-MIB removal were [O3 injection×contact time], H2O2/O3 for Post Peroxone of the G WTP, and [UV dose×H2O2 injection] for UV/H2O2 of the I WTP. As a result of comparing the operating cost(electric power cost + chemical cost) of each WTPs, I WTP was 6.6~24.3 KRW/m3 higher than G WTP. It is considered to be because the H2O2 injection was 11~43 times for UV/H2O2 than Post Peroxone. Optimal operating conditions could be derived through the performance evaluation of each oxidation facilities and chemical injection equations of each WTPs. The G WTP and the I WTP are equipped with pipe line for linked operation in the water supply pipes, so the water production for each WTPs can be distributed. In the case of the same water production, it was confirmed that the unit price can be reduced when the water production ratio of the G WTP is increased. Because the decrease in cost of the I WTP is higher than the increase in cost of the G WTP.Conclusions:It was confirmed that both Post Peroxone+GAC of G WTP and UV/H2O2+GAC F/A of I WTP were effective in 2-MIB treatment. As for the operating cost, it was analyzed that UV/H2O2 had higher unit pice than Post Peroxone because of the large amount of H2O2 injection. Considering the 2-MIB removal rate and operating cost of each WTPs, it was possible to derive the optimal operating conditions for each WTPs and a linked operation plan.

Hydrogen peroxide–induced oxidative stress impairs redox status and damages aerobic metabolism of breast muscle in broilers

Oxidative stress has always been a hot topic in poultry science. However, studies concerning the effects of redox status and glucose metabolism induced by hydrogen peroxide (H2O2) in the breast muscle of broilers have been rarely reported. This study was aimed to evaluate the impact of intraperitoneal injection of H2O2 on oxidative damage and glycolysis metabolism of breast muscle in broilers. We also explored the activation of the nuclear factor erythroid 2–related factor 2 (Nrf2) signaling pathway to provide possible mechanism of the redox imbalance. Briefly, a total of 320 one-day-old Arbor Acres chicks were randomly divided into 5 treatments with 8 replicates of 8 birds each (noninjected control, 0.75% saline-injected, 2.5, 5.0, and 10.0% H2O2-injected treatments). Saline group was intraperitoneally injected with physiological saline (0.75%) and H2O2 groups received an intraperitoneal injection of H2O2. The dosage of the injection was 1.0 mL/kg BW. All birds in the saline and H2O2 groups were injected on days 16 and 37 of the experimental period. At 42 d of age, 40 birds (8 cages per group and one chicken per cage) were selected to be stunned electrically (50 V, alternating current, 400 Hz for 5 s each one), and then immediately slaughtered via exsanguination. The results showed that broilers in the H2O2 injection group linearly exhibited higher contents of reactive oxygen species, carbonyl and malondialdehyde, and lower total antioxidant capacity and glutathione peroxidase activities. With the content of H2O2 increased, the H2O2 groups linearly downregulated the mRNA expressions of GPX, CAT, HMOX1, NQO1, and Nrf2 and its downstream target genes. In addition, H2O2 increased serum activities of creatine kinase and lactate dehydrogenase. Meanwhile, in the pectoral muscle, the glycogen content was linearly decreased, and the lactate content was linearly increased in muscle of broilers injected with H2O2. In addition, the activities of glycolytic enzymes including pyruvate kinase, hexokinase, and lactate dehydrogenase were linearly increased after exposure to H2O2. In conclusion, H2O2 injection could impair antioxidant status and enhance anaerobic metabolism of breast muscle in broilers.

Injection Metal-Assisted Catalytic Etching (MACE) of Si Powder: Discovery of Low-Load MACE and Pore Distribution Tunability Using Ag, Au, Pd, Pt and Cu Catalysts

Injection of H2O2 to control both the rate and extent of etching allowed us to discover a new regime of MACE with extremely small quantities of deposited metal as a catalyst: low-load MACE (LL-MACE).1 The structure of particles subjected to LL-MACE is completely different compared to conventional MACE. Si nanowires and mesoporous micro- or nano-particles are produced with high yield, low cost and controlled properties suitable for applications in e.g. lithium-ion batteries, drug delivery, as well as biomedical imaging and contrast enhancement. Different metal catalysts behave in distinct manners than can be traced to differences in nucleation and reaction kinetics.2 Not only Ag, Au, Pd and Pt but also inexpensive Cu can be used to perform LL-MACE.Previously, controlled reactant injection and acetic acid were used to transform stain etching into the improved process known as regenerative electroless etching (ReEtching).3 Here injection and acetic acid are exploited to enhance MACE and extend it to the low-load regime. Ag, Au, Pd, Pt and Cu can be galvanically deposited onto Si powder out of solutions of HF(aq). Nucleation of deposited metal nanoparticles is made more uniform by dispersing the Si powder in acetic acid and injecting the dissolved metal ions at a controlled rate. The use of a syringe pump to deliver not only metal ions during deposition but also the oxidant (H2O2) during MACE is essential for increased product uniformity and yield. Temperatures of ~0–50 °C and grades of Si (i.e. electronics grade Si with various doping levels or metallurgical grade Si) produced significantly different pore size distributions. Doping levels and the associated changes in band bending and space charge layer width4 are linked to changes in the pore size distribution.As shown in Fig. 1(A), high loading of Ag resulted in deposition of dendrites and Ag particles. These broke into ~50–100 nm Ag nanoparticles that etched in a correlated fashion to generate parallel etch track pores. The uniform size distribution of the Ag nanoparticles was generated dynamically during etching. This conventional high-load MACE (HL-MACE) did not produce Si nanowires (Si NWs) directly. However, etch track pore walls were cleaved readily by ultrasonic agitation to form Si NWs. Etching far removed from the metal nanoparticles (remote etching) also occurred for highly doped Si.As shown in Fig. 1(B), reducing the loading of Ag by a factor of 100 to 1000 compared to HL-MACE created 10–30 nm nanoparticles that etched in an uncorrelated fashion and generated randomly directed etch track pores. Significant etching far removed from the Ag catalyst also occurred. The combination of localized and remote etching resulted in a bimodal distribution of mesoporosity peaking at ~4 nm from remote etching and 10–30 nm from localized etching. The bimodal distribution was confirmed by the BJH method of nitrogen adsorption porosimetry. The pore size distribution could be controlled by changing the process temperature, the grade of Si and the metal composition. Whereas Ag, Au, Pd and Pt performed well in both the HL and LL limits, Cu generated porosification only in the LL limit.Funded by grants #314552 and #314412 from Academy of Finland and the National Science Foundation award #1825331. The microscopy studies were performed using the facilities in the UConn/Thermo Fisher Scientific Center for Advanced Microscopy and Materials Analysis (CAMMA). 1 K. Tamarov, J. D. Swanson, B. A. Unger, K. W. Kolasinski, A. T. Ernst, M. Aindow, V.-P. Lehto, and J. Riikonen, ACS Appl. Mater. Interfaces 12, 4787 (2020). 2 K. W. Kolasinski, W. B. Barclay, Y. Sun, and M. Aindow, Electrochim. Acta 158, 219 (2015). 3 K. W. Kolasinski, N. J. Gimbar, H. Yu, M. Aindow, E. Mäkilä, and J. Salonen, Angew. Chem., Int. Ed. Engl. 56, 624 (2017). 4 E. Torralba, S. Le Gall, R. Lachaume, V. Magnin, J. Harari, M. Halbwax, J.-P. Vilcot, C. Cachet-Vivier, and S. Bastide, ACS Appl. Mater. Interfaces 8, 31375 (2016). Figure 1