scholarly journals TiO2 Photocatalysis Causes DNA Damage via Fenton Reaction-Generated Hydroxyl Radicals during the Recovery Period

2007 ◽  
Vol 73 (23) ◽  
pp. 7740-7743 ◽  
Author(s):  
Gaëtan Gogniat ◽  
Sam Dukan
Keyword(s):  
Escherichia Coli ◽  
Reactive Oxygen Species ◽  
Dna Damage ◽  
Hydroxyl Radicals ◽  
Fenton Reaction ◽  
Recovery Period ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Tio2 Photocatalysis

ABSTRACT Here, we show that resistance of Escherichia coli to TiO2 photocatalysis involves defenses against reactive oxygen species. Results support the idea that TiO2 photocatalysis generates damage which later becomes deleterious during recovery. We found this to be partly due to DNA attack via hydroxyl radicals generated by the Fenton reaction during recovery.

scholarly journals Reactive Oxygen Species Regulate Oxygen-Sensitive Potassium Flux in Rainbow Trout Erythrocytes

2001 ◽  
Vol 117 (2) ◽  
pp. 181-190 ◽  
Author(s):  
Anna Yu Bogdanova ◽  
Mikko Nikinmaa
Keyword(s):  
Reactive Oxygen Species ◽  
Hydroxyl Radicals ◽  
Fenton Reaction ◽  
Copper Ions ◽  
Reactive Oxygen ◽  
Potassium Transport ◽  
Oxygen Species ◽  
Hypoxic Conditions ◽  
Potassium Flux ◽  
Oxygen Sensitive

In the present study, we have investigated if reactive oxygen species are involved in the oxygen-dependent regulation of potassium-chloride cotransport activity in trout erythrocyte membrane. An increase in the oxygen level caused an increase in chloride-sensitive potassium transport (K+-Cl− cotransport). 5 mM hydrogen peroxide caused an increase in K+-Cl− cotransport at 5% oxygen. The increase in flux could be inhibited by adding extracellular catalase in the incubation. Pretreatment of the cells with mercaptopropionyl glycine (MPG), a scavenger of reactive oxygen species showing preference for hydroxyl radicals, abolished the activation of the K+-Cl− cotransporter by increased oxygen levels. The inhibition by MPG was reversible, and MPG could not inhibit the activation of transporter by the sulfhydryl reagent, N-ethylmaleimide, indicating that the effect of MPG was due to the scavenging of reactive oxygen species and not to the reaction of MPG with the cotransporter. Copper ions, which catalyze the production of hydroxyl radicals in the Fenton reaction, activated K+-Cl− cotransport significantly at hypoxic conditions (1% O2). These data suggest that hydroxyl radicals, formed from O2 in close vicinity to the cell membrane, play an important role in the oxygen-dependent activation of the K+-Cl− cotransporter.

A Novel pH-responsive Fe-MOF System for Enhanced Cancer Treatment Mediated by Fenton Reaction

2021 ◽  
Author(s):  
Senlin Wang ◽  
Hong-Shuai Wu ◽  
Kai Sun ◽  
Jinzhong Hu ◽  
Fanghui Chen ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Hydroxyl Radical ◽  
Cancer Treatment ◽  
Cell Apoptosis ◽  
Fenton Reaction ◽  
Reactive Oxygen ◽  
Cationic Polymer ◽  
Intracellular Reactive Oxygen Species ◽  
Oxygen Species ◽  
Ph Responsive

Recently, the toxic hydroxyl radical (·OH) has received wide interest in inducing cell apoptosis by increasing the intracellular reactive oxygen species (ROS) levels. Herein, a cationic polymer (MV-PAH) was rationally...

scholarly journals Vesicular Formation of Trans-Ferulic Acid: an Efficient Approach to Improve the Radical Scavenging and Antimicrobial Properties

2021 ◽  
Author(s):  
Anahita Rezaeiroshan ◽  
Majid Saeedi ◽  
Katayoun Morteza-Semnani ◽  
Jafar Akbari ◽  
Akbar Hedayatizadeh-Omran ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Reactive Oxygen Species ◽  
Ferulic Acid ◽  
Reactive Oxygen Species Production ◽  
Radical Scavenging ◽  
Reactive Oxygen ◽  
Entrapment Efficiency ◽  
The Body ◽  
Oxygen Species ◽  
Species Production

Abstract Purposes Reactive oxygen species production is harmful to human’s health. The presence of antioxidants in the body may help to diminish reactive oxygen species. Trans-ferulic acid is a good antioxidant, but its low water solubility excludes its utilization. The study aims to explore whether a vesicular drug delivery could be a way to overcome the poor absorption of trans-ferulic acid hence improving its antimicrobial efficiency and antioxidant effect. Methods Niosomal vesicles containing the drug were prepared by film hydration method. The obtained vesicles were investigated in terms of morphology, size, entrapment efficiency, release behavior, cellular cytotoxicity, antioxidant, cellular protection study, and antimicrobial evaluations. Results The optimized niosomal formulation had a particle size of 158.7 nm and entrapment efficiency of 21.64%. The results showed that the optimized formulation containing 25 μM of trans-ferulic acid could enhance the viability of human foreskin fibroblast HFF cell line against reactive oxygen species production. The minimum effective dose of the plain drug and the niosomal formulation against Staphylococcus aurous (ATCC 29213) was 750 µg/mL and 375 µg/mL, respectively, and for Escherichia coli (ATCC 25922), it was 750 µg/mL and 187/5 µg/mL, respectively. The formulation could also improve the minimum bactericidal concentration of the drug in Staphylococcus aurous, Escherichia coli, and Acinobacter baumannii (ATCC 19606). Conclusion These results revealed an improvement in both antibacterial and antioxidant effects of the drug in the niosomal formulation.

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