Highly efficient UV/H2O2 technology for the removal of nifedipine antibiotics: Kinetics, co-existing anions and degradation pathways

This study investigates the degradation of nifedipine (NIF) by using a novel and highly efficient ultraviolet light combined with hydrogen peroxide (UV/H2O2). The degradation rate and degradation kinetics of NIF first increased and then remained constant as the H2O2 dose increased, and the quasi-percolation threshold was an H2O2 dose of 0.378 mmol/L. An increase in the initial pH and divalent anions (SO42- and CO32-) resulted in a linear decrease of NIF (the R2 of the initial pH, SO42- and CO32- was 0.6884, 0.9939 and 0.8589, respectively). The effect of monovalent anions was complex; Cl- and NO3- had opposite effects: low Cl- or high NO3- promoted degradation, and high Cl- or low NO3- inhibited the degradation of NIF. The degradation rate and kinetics constant of NIF via UV/H2O2 were 99.94% and 1.45569 min-1, respectively, and the NIF concentration = 5 mg/L, pH = 7, the H2O2 dose = 0.52 mmol/L, T = 20 ℃ and the reaction time = 5 min. The ·OH was the primary key reactive oxygen species (ROS) and ·O2- was the secondary key ROS. There were 11 intermediate products (P345, P329, P329-2, P315, P301, P274, P271, P241, P200, P181 and P158) and 2 degradation pathways (dehydrogenation of NIF → P345 → P274 and dehydration of NIF → P329 → P315).

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Photocatalytic degradation kinetics of humic acid in aqueous TiO2 dispersions: the influence of hydrogen peroxide and bicarbonate ion

Water Science & Technology ◽

10.2166/wst.1996.0180 ◽

1996 ◽

Vol 34 (9) ◽

pp. 73-80 ◽

Cited By ~ 24

Author(s):

Miray Bekbölet ◽

Isil Balcioglu

Keyword(s):

Hydrogen Peroxide ◽

Humic Acid ◽

Photocatalytic Degradation ◽

Rate Constants ◽

Degradation Rate ◽

Ph Value ◽

Degradation Kinetics ◽

Color Removal ◽

Degradation Data ◽

Kinetics Of

The degradation of humic acid in water by means of photocatalytic method has been studied. The influence of hydrogen peroxide and bicarbonate has also been investigated. The kinetics of the photocatalytic degradation of humic acid in various concentrations (50-500 mg/L) has been followed by the determination of TOC, COD and UV-vis spectra of the reaction solution. While the pseudo first order rate constants of 50 mg/L humic acid were found 0.016, 0.03 and 0.036 for TOC, Color400 and UV254, the degradation rate constants for these parameters were found 0.029, 0.069 and 0.057 in the presence of 1×10−2M H2O2. The Langmuir-Hinshelwood kinetic has also been sucessfully applied to the photocatalytic degradation data. It was found that bicarbonate ions slowed down the degradation rate by scavenging the hydroxyl radicals. Low pH value has been found to be favorable for color removal in the absence of hydrogen peroxide whereas natural pH gave the best results for color removal in the presence of hydrogen peroxide.

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Hydrogen peroxide-responsive AIE probe for imaging-guided organelle targeting and photodynamic cancer cell ablation

Materials Chemistry Frontiers ◽

10.1039/d1qm00328c ◽

2021 ◽

Author(s):

Qian Wu ◽

Youmei Li ◽

Ying Li ◽

Dong Wang ◽

Ben Zhong Tang

Keyword(s):

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Cancer Cell ◽

Reactive Oxygen ◽

Living Cells ◽

Oxygen Species ◽

Cell Ablation ◽

Selective Monitoring ◽

Organelle Targeting

Hydrogen peroxide (H2O2), as one kind of key reactive oxygen species (ROS), is mainly produced endogenously primarily in the mitochondria. The selective monitoring of H2O2 in living cells is of...

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Intracellular Sources of ROS/H2O2 in Health and Neurodegeneration: Spotlight on Endoplasmic Reticulum

Cells ◽

10.3390/cells10020233 ◽

2021 ◽

Vol 10 (2) ◽

pp. 233

Author(s):

Tasuku Konno ◽

Eduardo Pinho Melo ◽

Joseph E. Chambers ◽

Edward Avezov

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Endoplasmic Reticulum ◽

Neurodegenerative Diseases ◽

Antioxidative Enzymes ◽

Redox Reactions ◽

Ros Production ◽

Oxygen Species ◽

Specific Target

Reactive oxygen species (ROS) are produced continuously throughout the cell as products of various redox reactions. Yet these products function as important signal messengers, acting through oxidation of specific target factors. Whilst excess ROS production has the potential to induce oxidative stress, physiological roles of ROS are supported by a spatiotemporal equilibrium between ROS producers and scavengers such as antioxidative enzymes. In the endoplasmic reticulum (ER), hydrogen peroxide (H2O2), a non-radical ROS, is produced through the process of oxidative folding. Utilisation and dysregulation of H2O2, in particular that generated in the ER, affects not only cellular homeostasis but also the longevity of organisms. ROS dysregulation has been implicated in various pathologies including dementia and other neurodegenerative diseases, sanctioning a field of research that strives to better understand cell-intrinsic ROS production. Here we review the organelle-specific ROS-generating and consuming pathways, providing evidence that the ER is a major contributing source of potentially pathologic ROS.

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Upconversion-based nanosystems for fluorescence sensing of pH and H2O2

Nanoscale Advances ◽

10.1039/d0na01045f ◽

2021 ◽

Author(s):

Chunning Sun ◽

Michael Gradzielski

Keyword(s):

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Excitation Energy ◽

Reactive Oxygen ◽

Oxygen Species ◽

Fluorescence Sensing ◽

Living Organisms

Hydrogen peroxide (H2O2), a key reactive oxygen species, plays an important role in living organisms, industrial and environmental fields. Here, a non-contact upconversion nanosystem based on the excitation energy attenuation...

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Hydrogen peroxide and salinity stress act synergistically to enhance lipids production in microalga by regulating reactive oxygen species and calcium

Algal Research ◽

10.1016/j.algal.2020.102017 ◽

2020 ◽

pp. 102017

Author(s):

Tengsheng Qiao ◽

Yongteng Zhao ◽

Du-bo Zhong ◽

Xuya Yu

Keyword(s):

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Salinity Stress ◽

Reactive Oxygen ◽

Oxygen Species ◽

Lipids Production

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Cromoglycate and nedocromil enhanced the reactive oxygen species-dependent suppressions with, but not without, dexamethasone in ischaemic and histamine paw oedema of mice

Mediators of Inflammation ◽

10.1080/09629359791514 ◽

1997 ◽

Vol 6 (5-6) ◽

pp. 369-374

Author(s):

Y. Oyanagui

Keyword(s):

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Superoxide Dismutase ◽

Glucocorticoid Receptor ◽

Low Dose ◽

Natural Antioxidant ◽

Target Cells ◽

Oxygen Species ◽

Paw Oedema ◽

Β Carotene

Anti-inflammatory actions of two anti-allergic drugs, alone or with dexamethasone (Dex) were examined in two models, because inflammation is claimed to be important for allergic events, especially for asthma. Cromoglycate and nedocromil were tested in ischaemic- and histamineinduced paw oedema models of mice. These antiallergic drugs (1–100 mg/kg, i.p.) failed to suppress these oedemata, but enhanced the suppressions by a low dose of dexamethasone (0.1 mg/kg, s.c.) at 3–8 h after Dex injection. The mode of effects by anti-allergic drugs resembled that of a natural antioxidant (α-tocopherol, β-carotene etc.), and was different from that of an immunosuppressant like FK506. The enhancing potencies of the two anti-allergic drugs were similar at 6 h after Dex in both oedemata, and were diminished by superoxide dismutase (SOD) or catalase (i.p.). Cycloheximide completely abolished suppressions. Nedocromil, but not cromoglycate, inhibits inflammatory events. Therefore, there are common unknown actions by which the two anti-allergics enhance suppression by Dex. A possible mechanism of this action was supposed to enhance the superoxide and/or hydrogen peroxide-dependent glucocorticoid receptor (GR) signalling in the target cells.

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Novel Antioxidant Properties of Doxycycline

International Journal of Molecular Sciences ◽

10.3390/ijms19124078 ◽

2018 ◽

Vol 19 (12) ◽

pp. 4078 ◽

Cited By ~ 9

Author(s):

Dahn Clemens ◽

Michael Duryee ◽

Cleofes Sarmiento ◽

Andrew Chiou ◽

Jacob McGowan ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Chronic Inflammation ◽

Antioxidant Properties ◽

Antibacterial Properties ◽

Reactive Oxygen ◽

Protein Adducts ◽

Oxygen Species ◽

Free System

Doxycycline (DOX), a derivative of tetracycline, is a broad-spectrum antibiotic that exhibits a number of therapeutic activities in addition to its antibacterial properties. For example, DOX has been used in the management of a number of diseases characterized by chronic inflammation. One potential mechanism by which DOX inhibits the progression of these diseases is by reducing oxidative stress, thereby inhibiting subsequent lipid peroxidation and inflammatory responses. Herein, we tested the hypothesis that DOX directly scavenges reactive oxygen species (ROS) and inhibits the formation of redox-mediated malondialdehyde-acetaldehyde (MAA) protein adducts. Using a cell-free system, we demonstrated that DOX scavenged reactive oxygen species (ROS) produced during the formation of MAA-adducts and inhibits the formation of MAA-protein adducts. To determine whether DOX scavenges specific ROS, we examined the ability of DOX to directly scavenge superoxide and hydrogen peroxide. Using electron paramagnetic resonance (EPR) spectroscopy, we found that DOX directly scavenged superoxide, but not hydrogen peroxide. Additionally, we found that DOX inhibits MAA-induced activation of Nrf2, a redox-sensitive transcription factor. Together, these findings demonstrate the under-recognized direct antioxidant property of DOX that may help to explain its therapeutic potential in the treatment of conditions characterized by chronic inflammation and increased oxidative stress.

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In situ degradability of dry matter and fibrous fraction of sorghum silage

Acta Scientiarum Animal Sciences ◽

10.4025/actascianimsci.v38i2.29576 ◽

2016 ◽

Vol 38 (2) ◽

pp. 171 ◽

Cited By ~ 1

Author(s):

Renê Ferreira Costa ◽

Daniel Ananias de Assis Pires ◽

Marielly Maria Almeida Moura ◽

José Avelino Santos Rodrigues ◽

Vicente Ribeiro Rocha Júnior ◽

...

Keyword(s):

Experimental Design ◽

Dry Matter ◽

Degradation Rate ◽

Degradation Kinetics ◽

Grain Sorghum ◽

Dual Purpose ◽

Ruminal Degradability ◽

Sorghum Silage ◽

Kinetics Of

This study aimed to evaluate in situ degradability and degradation kinetics of DM, NDF and ADF of silage, with or without tannin in the grains. Two isogenic lines of grain sorghum (CMS-XS 114 with tannin and CMS-XS 165 without tannin) and two sorghum hybrids (BR-700 dual purpose with tannin and BR-601 forage without tannin) were ensiled; dried and ground silage samples were placed in nylon bags and introduced through the fistulas. After incubation for 6, 12, 24, 48, 72 and 96 hours, bags were taken for subsequent analysis of fibrous fractions. The experimental design was completely randomized with 4 replicates and 4 treatments and means compared by Tukey’s test at 5% probability. As for the DM degradation rate, silage of CMSXS165without tannin was superior. Silages of genotypes BR700 and CMSXS 114 with tannin showed the highest values of indigestible ADF (59.54 and 43.09%). Regarding the NDF, the potential degradation of silage of CMSXS165 line without tannin was superior. Tannin can reduce ruminal degradability of the dry matter and fibrous fractions.

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