Stevia as a natural additive on gut health and cecal microbiota in broilers.

Stevia mash (SM), leaves of Stevia rebaudiana Bertoni plant, is an additive used in poultry that enhances growth and health. Objective: to determine the effect of 1 % SM on productive parameters, gut health, and the cecal microbiome in broilers between the first 15 and 21 days old. One hundred sixty male, 1-day-old broilers (48.5 ± 2.5 g) were divided into Control (C) without SM and Treated (T) with 1 % SM on diet, during 15/21 days. Each subgroup had eight broilers/five repetitions/treatment. At day 15 or 21, all broilers were dissected, Fabricius Bursa and Gut removed and processed for histomorphometry, followed by Villi Height/Crypt Deep (VH/CD) ratio. Conversion Index (CI) was determined. The V3-V4 region of 16S rRNA gene was amplified from DNA obtained from pooled cecal contents and sequenced on Illumina Miseq PE 2 × 250 platform. Sequence processing and taxonomic assignments were performed using the SHAMAN pipeline. Both T groups have better VH/CD Ratios than C groups (p ≤ 0.05). In guts, increased plasmatic and goblet cells number and thicker mucus layer were found in T15 and T21. All groups received SM showed early immunological maturity in Fabricius Bursa. IC was similar between all treatments. Faecalibacterium, Ruminococcus torques group, and Bacteroides were the major genera modulated by SM addition. At 15 and 21 days old, SM exerts a impact on diversity and evenness of the cecal microbiome.  Conclusion: SM (1 %) produced early immunologic maturity on Fabricius Bursa, increased intestinal functionality, and modified the microbiota, increasing beneficial microbial genera and microbial diversity.

A General Method to Establish the Relative Efficiency of Different Sonosensitizers to Generate ROS for SDT.

The most common way to demonstrate the reactive oxygen species (ROS)-mediated pathways in photodynamic therapy (PDT) and in sonodynamic therapy (SDT) is the use of specific ROS inhibitors. We present a general method to establish the relative efficiency of different sonosensitizers which produce the same ROS. To demonstrate it, we use peroxides as sonosensitizers which produce singlet molecular oxygen. The method is easily generalized by all types of ROS.

Generation of ROS mediated by mechanical waves (ultrasound) and its possible applications.

The thermal decomposition of 9,10 diphenylanthracene peroxide (DPAO2) generates DPA and a mix of triplet and singlet molecular oxygen. For DPAO2 the efficiency to produce singlet molecular oxygen is 0.35. On the other hand, it has shown that many thermal reactions can be carried out through the interaction of molecules with ultrasound. Ultrasound irradiation can create hydrodynamic stress (sonomechanical process), inertial cavitation (pyrolitic process) and long range effects mediated by radicals or ROS. Sonochemical reactions can be originated by pyrolytic like process, shock mechanical waves, thermal reactions and radical and ROS mediated reactions. Sonolysis of pure water can yield hydrogen or hydroxyl radicals and hydrogen peroxide (ROS). When DPAO2 in 1,4 dioxane solution is treated with 20 or 24kHz and different power intensity the production of molecular singlet oxygen is observed. Specific scavengers like tetracyclone (TC) are used to demonstrate it. The efficiency now is 0.85 showing that the sonochemical process is much more efficient that the thermal one. Another endoperoxide, artemisinin was also studied. Unlike the concept of photosensitizer of photodynamic therapy, in spite of large amount of reported results in literature, the term sonosensitizer and the sonosensitization process are not well defined. We define sonosensitized reaction as one in which a chemical species decompose as consequence of cavitation phenomena producing ROS or other radicals and some other target species does undergo a chemical reaction. The concept could be reach rapidly other peroxides which are now under experimental studies. For artemisinin, an important antimalarian and anticancer drug, was established that ultrasound irradiation increases the effectiveness of the treatment but without any explanation. We show that artemisinin is an endoperoxide and behaves as a sonosensitizer in the sense of our definition.

Estimation of the solvent reorganization energy and the absolute energy of solvation of charge-transfer states from their emission spectra.

We report herein the solvent and temperature effects on the emission of the intermolecular exciplexes 1-cyanonaphthalene/triethylamine and 1-methylnaphthalene/triethylamine and the intramolecular exciplexes formed by the bichromophoric compounds diethyl-(3-naphthalen-1-yl-propyl)-amine (I), diethyl-(2-naphthalen-1-yl-ethyl)-amine (II), 3-[ethyl-(2-naphthalen-1-yl-ethyl)-amino]-propionitrile (III) and 3-[(2-cyano-ethyl)-(2-naphthalen-1-yl-ethyl)-amino]-propionitrile (IV). The results are interpreted within the formalism of the semiclassical Marcus theory for radiative back electron transfer (BET) reactions. We show that, following a few simple assumptions, reliable values of the Gibbs free energy changes (DeltaG(epsilon)(-et)) and the solvent reorganization energies (lambda(epsilon)(s)) associated to the BET reactions (and their corresponding enthalpic and entropic contributions) can be estimated directly from the emission of the CT states. We also show that for the 1-cyanonaphthalene/triethylamine exciplex, which exhibits emission in the vapour phase, the experimental calculation of the absolute energy of solvation of the CT state (DeltaG(epsilon)(s)) is also possible. The calculated DeltaG(epsilon)(-et) correlate quite satisfactorily with the corresponding values obtained from independent electrochemical and kinetics experiments. The temperature effects on DeltaG(epsilon)(-et), lambda(epsilon)(s) and DeltaG(epsilon)(s) are discussed qualitatively using different solvation models. The limitations of the present approach for the estimation of DeltaG(epsilon)(-et) and lambda(epsilon)(s) and its possible application to more complex A/D systems are also examined.

An experimental and theoretical study on the electrostatic effect of an appended cationic group on electronic properties of aromatic systems.

Tetraalkylammonium salts, characterized by an aromatic system pending from one of the alkyl chains, are taken as model systems to study the spectroscopic and redox properties of the aromatic centre under the field effects exerted by the charged group through alkyl bridges of varying length. The changes in the aromatic's redox properties, due to the net field effect and its different components, are interpreted on theoretical bases.