Aurélien Trivella

University of Bordeaux · Environnements et Paléoenvironnements Océaniques et Continentaux (UMR 5805)

Ultrasound as a green and efficient process gains special attention in wastewater treatment. The ultrasound-assisted degradation of azoxystrobin, methoxyfenozide, and propyzamide as widely used pesticides for vine treatment was investigated. A wide range of ultrasonic power (40 to 140 W) and a single frequency (20 kHz) were applied. Degradation exp...

This study investigated the environmental fate of myrigalone A, a light absorbing natural herbicide found on leaves and fruits of Myrica gale. Myrigalone A was irradiated in water and as a dry solid deposit to simulate reactions on leaves, alone and in the presence of the terpenes generated by Myrica gale. The phototransformation was fast (t1/2 = 3...

Sulfonamides (SNs) are synthetic antimicrobial agents. These substances are continually introduced into the environment and they may spread and maintain bacterial resistance in the different compartments. The chlorination of two sulfonamides, namely sulfamethazine (SMT) and sulfamethoxypyridazine (SMP), was investigated in order to study their reac...

UV and IR photochemistries of malonaldehyde, the simplest molecule exhibiting an intramolecular proton exchange, have been studied in four cryogenic matrices at 4.3 K, N2, Ne, Ar and Xe. Samples have been irradiated using a UV and IR OPO type tunable laser, and with a broad band UV mercury lamp. UV and IR spectra have been recorded and compared wit...

Kinetics of photodegradation of novel oral anticoagulants dabigatran, rivaroxaban, and apixaban were studied under simulated solar light irradiation in purified, mineral, and river waters. Dabigatran and rivaroxaban underwent direct photolysis with polychromatic quantum yields of 2.2 × 10(-4) and 4.4 × 10(-2), respectively. The direct photodegradat...

The photochemical transformation of two antibacterial sulfonamides, namely sulfamethazine (SMT) and sulfamethoxypyridazine (SMP), and two tricyclic antidepressants, namely amitriptyline (AMT) and clomipramine (CMP) were investigated. Experiments conducted in river water under artificial sunlight irradiation show an acceleration of the degradation f...

In this study, we aimed to investigate the kinetics and the mechanism of reaction of the fluoroquinolone antibacterial danofloxacin (DANO) by free available chlorine (FAC) during water chlorination process. Kinetic study was thus performed at pH 7.2, 20 °C in the presence of an excess of total chlorine. Under these experimental conditions, a second...

The fate of four natural β-triketones (leptospermone, isoleptospermone, grandiflorone and flavesone, pKa = 4.0-4.5) in aqueous solution, in the dark and upon simulated solar light irradiation was investigated. In anionic form, β-triketones undergo slow dark oxidation and photolysis with polychromatic quantum yields varying from 1.2 × 10(-4) to 3.7...

In this study, experimental far infrared measurements of l-serine, l-threonine, l-cysteine, and l-methionine are presented showing the spectra for the 1.0-13.0 pH range. In parallel, solid state DFT calculations were performed on the amino acid zwitterions in the crystalline form. We focused on the lowest frequency far infrared normal modes, which...

Photodynamic therapy (PDT) and vascular-disrupting agents (VDA) each have their advantages in the treatment of solid tumors, but also present drawbacks. In PDT, hypoxia at the center of the tumor limits conversion of molecular oxygen into singlet oxygen, while VDAs are deficient at affecting the rim of the tumor. A phthalocyanine–chalcone conjugate...

Water extracts from winery by-products exhibited significant plant defense inducer properties. Experiments were conducted on three marc extracts containing various amounts of polyphenols and anthocyanins. Infiltration of red, white and seed grape marc extracts into tobacco leaves induced hypersensitive reaction-like lesions with cell death evidence...

Water extracts from winery by-products exhibited significant plant defense inducer properties. Experiments were conducted on three marc extracts containing various amounts of polyphenols and anthocyanins. Infiltration of red, white and seed grape marc extracts into tobacco leaves induced hypersensitive reaction-like lesions with cell death evidence...

Contamination by toxic agents in the environment has become matters of concern to agricultural countries. Sulcotrione, a triketone herbicide used to control dicotyledonous weeds in maize culture is rapidly photolyzed on plant foliage and generate two main photoproducts the xanthene-1,9-dione-3,4-dihydro-6-methylsulfonyl and 2-chloro-4-mesylbenzoic...

The presence of physisorbed water during the silanization of silica is well-known for strongly influencing the silane reactivity at the interface. In this work, the reactivity of bis[3-(triethoxysilyl)propyl] tetrasulfide (TESPT), widely used in the rubber industry, on hydrated precipitation silica was investigated by time-resolved operando FTIR sp...

The photophysical properties of several photosensitizers (PSs) included or grafted in silica monoliths were compared to their properties in solution. The effects of the solid support on their steady-state and transient absorption spectra, on their quantum yields of singlet oxygen (1O2) production and on their ability to photo-induce the oxidation o...

Perinaphthenone (1H-phenalen-1-one, PN) is a reference photosensitizer producing singlet oxygen with a quantum yield close to one in a large variety of solvents. It is also the basic structure of a class of phototoxic phytoalexins. In this work, the PN photoreactivity was studied for the first time in a paraffinic wax, used as model of leaf epicuti...

New methylene blue () and methylene violet () are known for their photosensitizing properties for singlet oxygen ((1)O2) generation upon visible-light irradiation, and various examples of their use in the photodynamic inactivation of microorganisms and for photomedicinal purposes have been reported. However, their photophysical properties have neve...

Photodynamic therapy (PDT) and vascular-disrupting agents (VDA) have each their advantages in the treatment of solid tumors but also present drawbacks. In PDT, hypoxia at the center of the tumor limits convertion of molecular oxygen into singlet oxygen, when VDAs are deficient at affecting the rim of the tumor. A phthalocyanine-chalcone conjugate c...

Contamination by toxic agents in the environment has become matters of concern to agricultural countries. Sulcotrione, a triketone herbicide used to control dicotyledonous weeds in maize culture is rapidly photolyzed on plant foliage and generate two main photoproducts the xanthene-1,9-dione-3,4-dihydro-6-methylsulfonyl and 2-chloro-4-mesylbenzoic...

Photolysis may be a significant route of pesticide dissipation on crops, leading to an increase of pesticide use. Spraying strong absorbing compounds (photoprotector) along with pesticide is an attractive strategy to prevent the photodegradation phenomenon. The aim of this study is to get a better understanding of the parameters governing the photo...

This study compares the behavior as cytochrome c oxidase (CcO) functional and structural models of a series of reported and unreported ligands that provide either a binding site for copper without a built-in proximal base, or both a flexible binding site for copper and a built-in proximal base, or a fixed binding site for copper with a built-in pro...

Spectroscopic techniques that use the low frequency region are strongly emerging for the study of biological molecules. Far infrared and far Raman spectroscopies, THz time domain approaches and inelastic neutron scattering reveal the presence of vibrational modes involving inter-and intramolecular hydrogen bonding. Due to their collective nature, s...

The use of the far-infrared spectral range presents a novel approach for analysis of the hydrogen bonding in proteins. Here it is presented for the analysis of Fe--S vibrations (500-200 cm(-1)) and of the intra- and intermolecular hydrogen bonding signature (300-50 cm(-1)) in the Rieske protein from Thermus thermophilus as a function of temperature...

The use of the far IR spectral range presents a novel approach for analysis of proteins. Here it is presented for the analysis of Fe-S vibrations (500-200 cm-1) and of the intra-and intermolecular H-bonding signature (300-50 cm-1) in Rieske proteins and lipids in function of T, redox state and pH.

UV and IR photoreactivities of acetylacetone isolated at 4.3 K in four matrixes (N(2), Ne, Ar, Xe), pure and doped with O(2) are investigated, using either tunable UV and IR optical parametric oscillators, or a broad band mercury lamp. Samples are probed by UV and FTIR spectroscopies: electronic and vibrational transitions are assigned and irradiat...

Far infrared spectra of zwitterionic, cationic, and anionic forms of aliphatic amino acids in solid state have been studied experimentally. Measurements were done on glycine, L-alanine, L-valine, L-leucine, and L-isoleucine powder samples and film samples obtained from dried solutions prepared at pH ranging from 1 to 13. Solid state density functio...

The basic motions and the conformational flexibility of a protein have a strong impact on its molecular recognition properties and ultimately on its function. In the far infrared (or THz) spectral range the breathing of the hydrogen bonds can be monitored, providing essential information on local dynamics and mechanism. The use of this spectral ran...

UV- and IR-induced photoisomerization of acetylacetone trapped in a nitrogen matrix at 4.3 K have been carried out using a tunable optical parametric oscillator type laser, or a mercury vapor lamp, coupled with Fourier Transform IR and UV spectroscopies. After deposition, the main form present in the cryogenic matrix is that chelated (enol). Upon U...

The structure and reactivity of the eight enolic forms (one chelated and seven non-chelated) of malonaldehyde and acetylacetone are compared through theoretical and experimental data. Ground-state geometries, energies, and vibrational frequencies are calculated with the B3LYP/6-311++G(2d,2p) model chemistry. The electronic delocalization as well as...

Cryogenic matrix isolation experiments have allowed the measurement of the UV absorption spectra of the high-energy non-chelated isomers of acetylacetone, these isomers being produced by UV irradiation of the stable chelated form. Their identification has been done by coupling selective UV-induced isomerization, infrared spectroscopy, and harmonic...