A5084622100- Photochemistry and Electron Transfer Studies
- Free Radicals and Antioxidants
- Ruminant Nutrition and Digestive Physiology
- Animal Nutrition and Physiology
- Nuts composition and effects
- Essential Oils and Antimicrobial Activity
- Rabbits: Nutrition, Reproduction, Health
- Bee Products Chemical Analysis
- Spectroscopy and Quantum Chemical Studies
- Antioxidant Activity and Oxidative Stress
- Photodynamic Therapy Research Studies
- Phytochemicals and Antioxidant Activities
- Radical Photochemical Reactions
- Meat and Animal Product Quality
- Agricultural and Food Production Studies
- Molecular Junctions and Nanostructures
- Electrochemical Analysis and Applications
- Moringa oleifera research and applications
- Agroforestry and silvopastoral systems
- CO2 Reduction Techniques and Catalysts
- Phytochemistry Medicinal Plant Applications
- Agriculture Sustainability and Environmental Impact
- Photopolymerization techniques and applications
- Soil and Land Suitability Analysis
- Inorganic and Organometallic Chemistry
Universidade Estadual de Maringá
2019-2025
Alltech (United States)
2023
Corporación Universitaria Remington
2023
University of Tolima
2021
Universidad Nacional Autónoma de México
2020
National University of Río Cuarto
1984-2007
National University of Engineering
2001
Natural additives are a promising tool in modulating rumen fermentation due to the recent concerns regarding microbial resistance antibiotics. We evaluate antimicrobial capacity of different levels (10, 20, 50 and 100 mg/L) monensin, oregano essential oil (Origanum vulgare L), castor (Ricinus communis) Baccharis dracunculifolia (BD) hydroethanolic extract against gram-negative (Prevotella albensis, Prevotella bryantii Treponema saccharophilum) gram-positive (Ruminococcus albus, Ruminococcus...
This work was realized to study the antimicrobial activity, pH, ammonia, antioxidant volatile acid fatty and in liquor rumen of different additives combinations (monensin – MONE, monensin + virginiamycin MO+VI mineral traces yeast MO+MY) compared control CONT (without additives). The activity studied against four strains Gram-positives ruminal bacteria seven Gram-negatives bacteria. concentration MONE 37.7 g/L, 42.7 g/L MO+ML 39.3 g/L. Cultivation performed at 39° C, growth evaluated by...
Summary This paper describes the interaction between photochemically generated singlet molecular oxygen [O 2 ( 1 Δ g )] and a series of naturally occurring flavonoids (FL) (2′,4′‐dihydroxychalcone I ), 2′,4′‐dihydroxy, 3′‐methoxy chalcone II 7‐hydroxyflavanone III ) 7‐hydroxy‐8‐methoxyflavanone IV all obtained from Zuccagnia punctata Cav. The properties these compounds as generators quenchers known oxidative species O upon direct dye‐sensitized photoirradiation, were investigated....
Abstract The fruits of Tamarindus indica L. are consumed worldwide, with various parts the plant being used for medicinal purposes. residues (pericarp and seeds) generated during cellulose processing significant value as they contain bioactive compounds diverse biological activities. objective this study was to evaluate chemical constituents ethyl acetate fraction possible substitutes synthetic properties using ultra‐high performance liquid chromatography coupled high‐resolution mass...
The visible-light irradiation of the system Rivoflavin plus 3-hydroxyflavone or 7-hydroxyflavone, under aerobic conditions, produces a series competitive processes that depend on relative concentrations pigment and flavones. picture comprises photochemical mechanisms potentially operate in nature. They mainly include quenching Rf singlet ( 1 * ) triplet 3 excited states (with bimolecular rate constants order 10 9 M 1 s superoxide radical anion-mediated reactions. participation oxidative...
The triplet state properties of flavone (2-phenylchromone) have been investigated by laser flash photolysis. Excitation at 337 nm was carried out means a nitrogen laser. T–T absorption spectrum determined in homogeneous solvents (benzene, ethanol, acetonitrile) and micellar solutions SDS, CTAC Brij 35. position the two maxima 370 620 practically independent solvent. self quenching rate constants were are range 1.8–3.0 × 108 dm3 mol–1 s–1. effect surfactant concentration on yield decay...
Abstract The protective effect of the polyhydroxyflavones Fisetin and Baicalein on sensitized [O 2 ( 1 δ g ] ‐ mediated photooxidation fats was investigated through a kinetic study. These flavonoids at concentrations in order few ppm efficiently inhibit photoperoxidation linoleic acid, which chosen as an example photooxidizable fat. This property attributed to ability quench photochemically generated O ). rate constants for such process quenching were 1.9 1.4 × 10 8 M −1 S respectively....
The quenching of the excited singlet states naphthalene, phenanthrene and pyrene by polychlorobenzenes has been studied in acetonitrile static time-resolved techniques. bimolecular rate constants correlate well with Gibbs energy change for a charge-transfer process which hydrocarbon acts as an electron donor, when overall reaction is negative. dechlorination was not observed even after several hours continuous irradiation at longest absorption band hydrocarbon. In agreement this, laser flash...
Feline infectious peritonitis (FIP) is one of the most prevalent viral diseases wild and domestic cats.Despite its multisystemic character, cutaneous lesions FIP have been rarely described.A skin biopsy from a 14-month-old male neutered shorthaired cat with slightly raised, 5 mm in diameter ulcer on dorsal cervical area presumptive clinical diagnosis was submitted for histological examination.Histological changes consisted ulcerative dermatitis perivascular, periadnexal, interstitial...
This study aimed to evaluate the in vitro antibacterial activity of Baccharis dracunculifolia and Tamarindus indica L. aqueous extract, cashew nut shell liquid (CNSL) natural extracts, clove essential oil (EO) against five species Gram-negative ruminal bacteria. Cultures were grown anaerobic media containing 0.1, 0.2, 0.5 1.0 mg mL-1 extracts or oils. Growth was evaluated by monitoring optical density (OD 600 nm) at intervals 0, 8, 12 24 hours incubation 39° C. The baccharis tamarind CNSL...
The photophysical behaviour of N,N-diethyl-2-(1-naphthyl)ethylamine I, N-benzyl-N-ethyl-2-(1-naphthyl)ethylamine VI and N-ethyl-2-(1-naphthyl)-N-(2,4,6-trichlorobenzyl)ethylamine VII, molecules that are able to form intramolecular exciplexes, has been examined in ethyl acetate. Compounds I fluorescent, but VII is non fluorescent decomposes with formation hydrogen chloride. the intermolecular exciplexes formed by naphthalene N bifunctional quenchers N,N-diethylbenzylamine...
Abstract The ability of mono‐, di‐, tri‐and tetra‐hydroxyflavones (7‐and 3‐hy‐droxyflavones, 7, 8‐dihydroxyflavone, baicalein and fisetin) to act as photoprotectors against singlet molecular oxygen [O 2 (Δ g )]‐initiated photooxidation fats has been established by a kinetic study. overall quenching rate constants for series five hydroxyflavones perfectly parallel their respective behaviour inhibitors the sensitized linoleic acid. best antioxidative effect was exerted 7‐hydroxyflavone which...
The electron transfer quenching of the excited singlet and triplet states 9-methylcarbazole (MCBz) by p-dicyanobenzene (DCNB) was investigated in several solvents. While rate constant is diffusion controlled all solvents, constants increase with solvent polarity. In acetonitrile, free radical ions are produced high yield from both states, while a very low observed polarity effect two salts, tetrabutylammonium pechlorate (TBAP) LiClO 4 THF. presence an enhancement observed. Two different...
The fluorescence of the intramolecular exciplex formed by N,N-diethyl-2-(1-naphthyl)ethylamine (I), was quenched chlorobenzenes in acetonitrile, tetrahydrofuran, ethylacetate and cyclohexane. An electron transfer mechanism proposed for quenching process. It observed that second-order rate constants, when process is not diffusionally controlled, markedly increase as relative permittivity solvent decreases. This unusual behaviour analysed terms Marcus theory reactions. suggested with...