Concept

Polyphénol

Publications associées (27)

Electrospun zein incorporating phycocyanin and Spirulina extract: Fabrication, characterization, and potential application

Electrospinning was used to develop zein fibers containing phycocyanin and aqueous-ethanolic extract of Spirulina (AEES) for elucidating the potent packaging properties of phycocyanin and AEES on walnut samples. Morphological results revealed that using th ...

Elsevier2023

Photochemical oxidation of phenols and anilines mediated by phenoxyl radicals in aqueous solution

Urs von Gunten, Stephanie Christa Remke

Reactive intermediates formed upon irradiation of chromophoric dissolved organic matter (CDOM) contribute to the degradation of various organic contaminants in surface waters. Besides well-studied "short-lived" photo oxidants, such as triplet state CDOM (3 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Impact of the Natural Compound Urolithin A on Health, Disease, and Aging

Johan Auwerx, Davide D'Amico, Pamela Solange Valdés Undurraga, Pénélope Andreux

Urolithin A (UA) is a natural compound produced by gut bacteria from ingested ellagitannins (ETs) and ellagic acid (EA), complex polyphenols abundant in foods such as pomegranate, berries, and nuts. UA was discovered 40 years ago, but only recently has its ...

2021

Phototransformation of Organic Contaminants in Aquatic Systems: Characterization of Long-Lived Photooxidants Derived from Dissolved Organic Matter

Stephanie Christa Remke

The increasing interest in the fate of organic contaminants in the aquatic environment requires the elucidation of relevant abiotic transformation processes. These processes often involve the ubiquitous dissolved organic matter (DOM), a complex mixture of ...

EPFL2021

Catechin reduces phototoxic effects induced by protoporphyrin IX-based photodynamic therapy in the chick embryo chorioallantoic membrane

Georges Wagnières, Jaroslava Joniová

Significance: Side effects of many cancer treatments are associated with the production of reactive oxygen species (ROS) in normal tissues. This explains why patients treated by photodynamic therapy (PDT) often suffer from skin photosensitization, whereas ...

SPIE Society of Photo-optical Instrumentation Engineers2020

Efficiency of pre-oxidation of natural organic matter for the mitigation of disinfection byproducts: Electron donating capacity and UV absorbance as surrogate parameters

Urs von Gunten

Pre-oxidation is often used before disinfection with chlorine to decrease the reactivity of the water matrix and mitigate the formation of regulated disinfection byproducts (DBPs). This study provides insights on the impact of oxidative pre-treatment with ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Polyphenols as Morphogenetic Agents for the Controlled Synthesis of Mesoporous Silica Nanoparticles

Fabien Sorin, Jialuo Luo

Non-surfactant-induced synthesis of mesoporous silica nanoparticles (MSNPs) is gaining increasing interest because of their low toxicity and simple purification compared to conventional surfactant-based methods. Tannic acid (TA), considered as a glucose-de ...

AMER CHEMICAL SOC2019

Fractionation of lignocellulosic biomass to produce uncondensed aldehyde-stabilized lignin

Jeremy Luterbacher, Masoud Talebi Amiri, Ydna Marie Questell-Santiago, Graham Reid Dick

Lignin is one of the most promising sources of renewable aromatic hydrocarbons. Current methods for its extraction from lignocellulosic biomass—which include the kraft, sulfite, and organosolv processes—result in the rapid formation of carbon–carbon bonds, ...

Nature Publishing Group2019

OsCAldOMT1 is a bifunctional O-methyltransferase involved in the biosynthesis of tricin-lignins in rice cell walls

Wu Lan

Lignin is a phenylpropanoid polymer produced in the secondary cell walls of vascular plants. Although most eudicot and gymnosperm species generate lignins solely via polymerization of p-hydroxycinnamyl alcohols (monolignols), grasses additionally use a fla ...

Nature Research2019

Ozone and chlorine reactions with dissolved organic matter - Assessment of oxidant-reactive moieties by optical measurements and the electron donating capacities

Urs von Gunten

Oxidation processes are impacted by the type, concentration and reactivity of the dissolved organic matter (DOM). In this study, the reactions between various types of DOM (Suwannee River fulvic acid (SRFA), Nordic Reservoir NOM (NNOM) and Pony Lake fulvic ...

2018

Ozonation of Para-Substituted Phenolic Compounds Yields p-Benzoquinones, Other Cyclic α,β-Unsaturated Ketones, and Substituted Catechols

Urs von Gunten, Peter Rudolf Tentscher

Phenolic moieties are common functional groups in organic micropollutants and in dissolved organic matter, and are exposed to ozone during drinking water and wastewater ozonation. Although unsubstituted phenol is known to yield potentially genotoxic p-benz ...

2018

Sphagnum Species Modulate their Phenolic Profiles and Mycorrhizal Colonization of Surrounding Andromeda polifolia along Peatland Microhabitats

Alexandre Buttler, Vincent Eric Jules Jassey

Sphagnum mosses mediate long-term carbon accumulation in peatlands. Given their functional role as keystone species, it is important to consider their responses to ecological gradients and environmental changes through the production of phenolics. We compa ...

SPRINGER2018

Two analytical approaches quantifying the electron donating capacities of dissolved organic matter to monitor its oxidation during chlorination and ozonation

Urs von Gunten

Electron-donating activated aromatic moieties, including phenols, in dissolved organic matter (DOM) partially control its reactivity with the chemical oxidants ozone and chlorine. This comparative study introduces two sensitive analytical systems to direct ...

2018

Soluble and Solid Iron Reduction Assays with Desulfitobacterium hafniense

Julien Maillard

There is a pressing need to develop sustainable and efficient methods to protect and stabilize iron objects. To develop a conservation-restoration method for corroded iron objects, this bio-protocol presents the steps to investigate reductive dissolution o ...

2018

Oxidative stability and microstructure of 5% fish-oil-enriched granola bars added natural antioxidants derived from brown alga Fucus vesiculosus

Louise Helene Soegaard Jensen

The aims of this study were to (i) investigate the ability of Icelandic brown algae Fucus vesiculosus extracts to inhibit lipid oxidation in granola bars fortified with fish oil-in-water emulsion; (ii) investigate whether addition of the seaweed extracts a ...

Wiley-Blackwell2017

Modulation of AMPK's activity via genetic tools and food-derived compounds as a novel approach to Parkinson's disease treatment

Wojciech Janusz Bobela

Aging is considered as a major risk factor for Parkinsonâ s disease (PD) and can be defined as a gradual decline in the ability of biological systems to efficiently renew structural and functional components, which may lead to perturbations in energetic h ...

EPFL2016

Economical Analysis of a Pressurized Fluid-Based Process Applied for Phytochemicals Recovery in a Sustainable Biorefinery Concept for Brazilian Ginseng Roots

François Maréchal

A growing number of technologies are being developed in order to produce different high added value products, such as phytochemicals, ethanol and other chemicals from biomass, representing an important trend that needs to be evaluated. The use of pressuriz ...

Aidic Servizi Srl2016

Antioxidant Assay Based on Quenching of Photocatalytically Generated Reactive Oxygen Species

Hubert Girault, Mohamad Hojeij

A method based on photogeneration of OH radicals in water from TiO2 nanoparticles was developed to study the kinetics of oxidation of organic molecules which were used as biological antioxidants. The kinetics of oxidation of terephthalic acid as a referenc ...

Elsevier Science Inc2016

Photosensitizing and Inhibitory Effects of Ozonated Dissolved Organic Matter on Triplet-Induced Contaminant Transformation

Urs von Gunten

Dissolved organic matter (DOM) is both a promoter and an inhibitor of triplet-induced organic contaminant oxidation. This dual role was systematically investigated through photochemical experiments with three types of DOM of terrestrial and aquatic origins ...

American Chemical Society2015

Light availability affects stream biofilm bacterial community composition and function, but not diversity

Tom Ian Battin

Changes in riparian vegetation or water turbidity and browning in streams alter the local light regime with potential implications for stream biofilms and ecosystem functioning. We experimented with biofilms in microcosms grown under a gradient of light in ...

Wiley-Blackwell2015