Photolysis of sulfamethazine using UV irradiation in an aqueous medium

The photochemical conversion of organic compounds on tailored transition metal oxide surfaces by (UV) irradiation has found wide applications ranging from the production of chemicals to the degradation of organic...

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The Role of the Reactive Species Involved in the Photocatalytic Degradation of HDPE Microplastics Using C,N-TiO2 Powders

Polymers ◽

10.3390/polym13070999 ◽

2021 ◽

Vol 13 (7) ◽

pp. 999 ◽

Cited By ~ 1

Author(s):

Aranza Denisse Vital-Grappin ◽

Maria Camila Ariza-Tarazona ◽

Valeria Montserrat Luna-Hernández ◽

Juan Francisco Villarreal-Chiu ◽

Juan Manuel Hernández-López ◽

...

Keyword(s):

Wastewater Treatment Plants ◽

Reaction System ◽

Terrestrial Ecosystems ◽

Degradation Process ◽

Reactive Species ◽

Hazardous Substances ◽

Wide Range ◽

Degradation Behaviors ◽

Environmentally Friendly Process

Microplastics (MPs) are distributed in a wide range of aquatic and terrestrial ecosystems throughout the planet. They are known to adsorb hazardous substances and can transfer them across the trophic web. To eliminate MPs pollution in an environmentally friendly process, we propose using a photocatalytic process that can easily be implemented in wastewater treatment plants (WWTPs). As photocatalysis involves the formation of reactive species such as holes (h+), electrons (e−), hydroxyl (OH●), and superoxide ion (O2●−) radicals, it is imperative to determine the role of those species in the degradation process to design an effective photocatalytic system. However, for MPs, this information is limited in the literature. Therefore, we present such reactive species’ role in the degradation of high-density polyethylene (HDPE) MPs using C,N-TiO2. Tert-butanol, isopropyl alcohol (IPA), Tiron, and Cu(NO3)2 were confirmed as adequate OH●, h+, O2●− and e− scavengers. These results revealed for the first time that the formation of free OH● through the pathways involving the photogenerated e− plays an essential role in the MPs’ degradation. Furthermore, the degradation behaviors observed when h+ and O2●− were removed from the reaction system suggest that these species can also perform the initiating step of degradation.

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Relevance of mitochondrial dysfunction during Sorafenib-induced cell death in liver cancer cells. Role of oxidative and nitrogen reactive species

Free Radical Biology and Medicine ◽

10.1016/j.freeradbiomed.2020.12.418 ◽

2021 ◽

Vol 165 ◽

pp. 54

Author(s):

Patricia de la Cruz-Ojeda ◽

M. Ángeles Rodríguez-Hernández ◽

Elena Navarro-Villarán ◽

Paloma Gallego ◽

Pavla Staňková ◽

...

Keyword(s):

Cell Death ◽

Liver Cancer ◽

Mitochondrial Dysfunction ◽

Cancer Cells ◽

Reactive Species ◽

Liver Cancer Cells ◽

Nitrogen Reactive Species

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Oxidation of Terpenoids to Achieve High-Value Flavor and Fragrances—Questioning Microalgae Oxidative Capabilities in the Biotransformation of the Sesquiterpene Valencene and of Selected Natural Apocarotenoids

Chemistry ◽

10.3390/chemistry3030059 ◽

2021 ◽

Vol 3 (3) ◽

pp. 821-830

Author(s):

Davide De Simeis ◽

Stefano Serra ◽

Alessandro Di Fonzo ◽

Francesco Secundo

Keyword(s):

Experimental Data ◽

Natural Products ◽

Aqueous Medium ◽

Photochemical Reaction ◽

Substrate Oxidation ◽

Market Size ◽

Chlorella Sp ◽

General Opinion ◽

Natural Way

Natural flavor and fragrance market size is expected to grow steadily due to the rising consumer demand of natural ingredients. This market request is guided by the general opinion that the production of natural compounds leads to a reduction of pollution, with inherent advantages for the environment and people’s health. The biotransformation reactions have gained high relevance in the production of natural products. In this context, few pieces of research have described the role of microalgae in the oxidation of terpenoids. In this present study, we questioned the role of microalgal based oxidation in the synthesis of high-value flavors and fragrances. This study investigated the role of three different microalgae strains, Chlorella sp. (211.8b and 211.8p) and Chlorococcum sp. (JB3), in the oxidation of different terpenoid substrates: α-ionone, β-ionone, theaspirane and valencene. Unfortunately, the experimental data showed that the microalgal strains used are not responsible for the substrate oxidation. In fact, our experiments demonstrate that the transformation of the four starting compounds is a photochemical reaction that involves the oxygen as oxidant. Even though these findings cast a shadow on the use of these microorganisms for an industrial purpose, they open a new possible strategy to easily obtain nootkatone in a natural way by just using an aqueous medium, oxygen and light.

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Synthesis of OFF-type zeolite in a quasi non aqueous medium: structure directing role of p-dioxane and alkaline cations

Microporous and Mesoporous Materials ◽

10.1016/s1387-1811(99)00009-8 ◽

1999 ◽

Vol 29 (3) ◽

pp. 405-412 ◽

Cited By ~ 6

Author(s):

A Matijasic ◽

J Patarin

Keyword(s):

Aqueous Medium ◽

Type Zeolite ◽

Alkaline Cations

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Glutathione Participation in the Prevention of Cardiovascular Diseases

Antioxidants ◽

10.3390/antiox10081220 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1220

Author(s):

Deyamira Matuz-Mares ◽

Héctor Riveros-Rosas ◽

María Magdalena Vilchis-Landeros ◽

Héctor Vázquez-Meza

Keyword(s):

Cardiovascular Diseases ◽

Superoxide Anion ◽

Reactive Nitrogen Species ◽

Hypochlorous Acid ◽

Reduced Glutathione ◽

Heart Diseases ◽

Reactive Species ◽

Oxygen Species ◽

Cardiovascular Pathologies

Cardiovascular diseases (CVD) (such as occlusion of the coronary arteries, hypertensive heart diseases and strokes) are diseases that generate thousands of patients with a high mortality rate worldwide. Many of these cardiovascular pathologies, during their development, generate a state of oxidative stress that leads to a deterioration in the patient’s conditions associated with the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). Within these reactive species we find superoxide anion (O2•–), hydroxyl radical (•OH), nitric oxide (NO•), as well as other species of non-free radicals such as hydrogen peroxide (H2O2), hypochlorous acid (HClO) and peroxynitrite (ONOO–). A molecule that actively participates in counteracting the oxidizing effect of reactive species is reduced glutathione (GSH), a tripeptide that is present in all tissues and that its synthesis and/or regeneration is very important to be able to respond to the increase in oxidizing agents. In this review, we will address the role of glutathione, its synthesis in both the heart and the liver, and its importance in preventing or reducing deleterious ROS effects in cardiovascular diseases.

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