Characterization of esterase activity in the Bianchetta trevigiana grape variety under reducing conditions

Giovanna Lomolino, Anna LanteDepartment of Agronomy Food Natural Resources Animals and Environment, Agripolis, Università di Padova Viale dell'Università, Padova, ItalyBackground and methods: While extensive research has been carried out on the enzymes responsible for ester synthesis and hydrolysis by wine strains of Saccharomyces cerevisiae, grape esterase activity is limited. In this study, the autochthonous grape variety, Bianchetta trevigiana, widespread in the Prosecco wine production area of Treviso, Conegliano, and Asolo, Italy, was characterized according to its esterase activity. Because grape skin is very rich in compounds which impart qualitative characteristics to wine, the study of esterase was carried out on this part of the fruit.Results: During enzyme extraction from grape skin, the presence of the reducing agent, β-mercaptoethanol, allowed a better protein yield but reduced esterase activity. Further addition of increasing doses of reducing agents to grape skin protein extract, such as of K2S2O5 (used in winemaking) and DTT, reduced or inhibited esterase activity. Even though the zymographic profiles of the extracts obtained with and without β-mercaptoethanol were qualitatively equal, the intensity of enzymatic bands, measured by densitometry, was different.Conclusion: The presence of reducing agents affected the activity of grape skin esterase, and given that this enzyme is involved in the hydrolysis and synthesis of esters, which are important compounds responsible for the flavor of wine, addition of reducing agents could affect the aromatic profile of wine.Keywords: esterase, grape, reducing agent, win

Magneto-elastic effects and magnetization plateaus in two dimensional systems

We show the importance of both strong frustration and spin-lattice coupling for the stabilization of magnetization plateaus in translationally invariant two-dimensional systems. We consider a frustrated spin-1/2 Heisenberg model coupled to adiabatic phonons under an external magnetic field. At zero magnetization, simple structures with two or at most four spins per unit cell are stabilized, forming dimers or $2 \times 2$ plaquettes, respectively. A much richer scenario is found in the case of magnetization $m=1/2$, where larger unit cells are formed with non-trivial spin textures and an analogy with the corresponding classical Ising model is detectable. Specific predictions on lattice distortions and local spin values can be directly measured by X-rays and Nuclear Magnetic Resonance experiments.Comment: 4 pages and 4 figure

Total phenolic content, antioxidant and antimicrobial activity of Haberlea rhodopensis extracts obtained by pressurized liquid extraction

The present study was designed to investigate the antioxidant and antimicrobial activities of pressurized liquid extracts from Haberlea rhodopensis Friv. The total phenolic content was performed using the Folin-Ciocalteu phenol reagent. To determine the antioxidant activities of the extracts, several complementary tests were used: ABTS and DPPH radical scavenging activities, oxygen radical absorbance capacity, and ferric-reducing antioxidant power assay. The phenolic concentration was 15.98±0.09 and 9.42±0.06 mg GAE g−1 DW for 70 and 85% ethanol extracts, respectively. Of all the performed methods, the highest antioxidant activity values were measured by the ORAC assay — 224.6±6.6 and 154.0±9.9 μM TE g−1 DW for 70 and 85% ethanol extracts, respectively. Results also showed that both extracts exhibited very weak antimicrobial activity against the examined microorganisms. However, the 70% ethanol extract possessed higher inhibition ability, which correlated with higher total phenolic content and antioxidant activity

Разработка программы мероприятий по внедрению наилучших доступных технологий на примере теплоэнергетики

В связи с изменениями экологического законодательства в РФ обязательным требованием будет являться переход предприятий на НДТ с 2020 года. В работе будут предложены мероприятия для уменьшения воздействия теплоэнергетических предприятий на атмосферный воздух путем перехода на НДТ.In connection with the change in environmental legislation in the Russian Federation, the mandatory requirement will be the transition to BAT since 2020. The work will propose measures to reduce the impact of heat power plants on atmospheric air by switching to BAT

Charge identification of fragments with the emulsion spectrometer of the FOOT experiment

The FOOT (FragmentatiOn Of Target) experiment is an international project designed to carry out the fragmentation cross-sectional measurements relevant for charged particle therapy (CPT), a technique based on the use of charged particle beams for the treatment of deep-seated tumors. The FOOT detector consists of an electronic setup for the identification of Z ≥ 3 fragments and an emulsion spectrometer for Z ≤ 3 fragments. The first data taking was performed in 2019 at the GSI facility (Darmstadt, Germany). In this study, the charge identification of fragments induced by exposing an emulsion detector, embedding a C2 H4 target, to an oxygen ion beam of 200 MeV/n is discussed. The charge identification is based on the controlled fading of nuclear emulsions in order to extend their dynamic range in the ionization response

Performance of the ToF detectors in the foot experiment

The FOOT (FragmentatiOn Of Target) experiment aims to deter- mine the fragmentation cross-sections of nuclei of interest for particle therapy and radioprotection in space. The apparatus is composed of several detectors that allow fragment identification in terms of charge, mass, energy and direction. The frag- ment time of flight (ToF) along a lever arm of ∼2 m is used for particle ID, requiring a resolution below 100ps to achieve a sufficient resolution in the fragment atomic mass identification. The timing performance of the ToF system evaluated with 12C and 16O beams is reviewed in this contribution

Charge identification of fragments with the emulsion spectrometer of the FOOT experiment

The FOOT (FragmentatiOn Of Target) experi- ment is an international project designed to carry out the fragmentation cross-sectional measurements relevant for charged particle therapy (CPT), a technique based on the use of charged particle beams for the treatment of deep-seated tumors. The FOOT detector consists of an electronic setup for the identification of Z >= 3 fragments and an emulsion spectrometer for Z <= 3 fragments. The first data taking was performed in 2019 at the GSI facility(Darmstadt, Germany). In this study, the charge identifi-cation of fragments induced by exposing an emulsion detector, embedding a C2H4 target, to an oxygen ion beam of 200 MeV/n is discussed. The charge identifica-tion is based on the controlled fading of nuclear emulsions in order to extend their dynamic range in the ionization response

Measuring the Impact of Nuclear Interaction in Particle Therapy and in Radio Protection in Space: the FOOT Experiment

In Charged Particle Therapy (PT) proton or 12C beams are used to treat deep-seated solid tumors exploiting the advantageous characteristics of charged particles energy deposition in matter. For such projectiles, the maximum of the dose is released at the end of the beam range, in the Bragg peak region, where the tumour is located. However, the nuclear interactions of the beam nuclei with the patient tissues can induce the fragmentation of projectiles and/or target nuclei and needs to be carefully taken into account when planning the treatment. In proton treatments, the target fragmentation produces low energy, short range fragments along all the beam path, that deposit a non-negligible dose especially in the first crossed tissues. On the other hand, in treatments performed using 12C, or other (4He or 16O) ions of interest, the main concern is related to the production of long range fragments that can release their dose in the healthy tissues beyond the Bragg peak. Understanding nuclear fragmentation processes is of interest also for radiation protection in human space flight applications, in view of deep space missions. In particular 4He and high-energy charged particles, mainly 12C, 16O, 28Si and 56Fe, provide the main source of absorbed dose in astronauts outside the atmosphere. The nuclear fragmentation properties of the materials used to build the spacecrafts need to be known with high accuracy in order to optimise the shielding against the space radiation. The study of the impact of these processes, which is of interest both for PT and space radioprotection applications, suffers at present from the limited experimental precision achieved on the relevant nuclear cross sections that compromise the reliability of the available computational models. The FOOT (FragmentatiOn Of Target) collaboration, composed of researchers from France, Germany, Italy and Japan, designed an experiment to study these nuclear processes and measure the corresponding fragmentation cross sections. In this work we discuss the physics motivations of FOOT, describing in detail the present detector design and the expected performances, coming from the optimization studies based on accurate FLUKA MC simulations and preliminary beam test results. The measurements planned will be also presented