National Academy of Sciences of Belarus

In order to improve pectin antioxidant properties and enlarge the field of its potential applications, ferulic acid grafted pectin conjugates (PE‐g‐FA) were prepared using laccase as the catalyst at 30°C in an aqueous medium. The structures of PE‐g‐FA were characterized using UV–vis, FTIR, and NMR (1H and 13C). In addition, the antioxidant activity of PE‐g‐FA was evaluated according to the DPPH and ABTS free radical scavenging ability. Olive oil in water emulsions, containing emulsifiers WPI and PE‐g‐FA, were assessed for their physical and oxidative stability through particle size, zeta‐potential, peroxide value (POV), and 2‐thiobarbituric acid reactive substance (TBARS) formation. The results indicated that the formation of covalent bonds between the pectin carboxymethyl groups and FA hydroxyl group. The determination of the total phenolic content showed that PE‐g‐FA contained seven times more polyphenols than native PE. DPPH and ABTS free radical scavenging rate of 0.5HMP‐g‐FA were increased by 56.83% and 18.90% compared with HMP, respectively. In addition, the emulsion stabilized by WPI and 0.5HMP‐g‐FA showed smallest and uniform average particle size (855.9 ± 51.13 nm) on the 1st day. Although its POV value was slightly higher than that of emulsion stabilized by WPI and HMP, it was much lower than that of control groups. Overall, these results have important implications for enzymatic modification of pectin to obtain high antioxidant products and their application in pectin‐based emulsions.

The crystal structure and vibrational spectra of CoFe 2 O 4 ferrite were studied using X-ray diffraction and Raman spectroscopy over a pressure range of 0–35[Formula: see text]GPa. A structural phase transition from the cubic [Formula: see text] phase to the post-spinel orthorhombic Bbmm phase occurs at a pressure of approximately 23[Formula: see text]GPa through a two-phase region. Pressure-induced changes in the structural parameters, lattice distortion, and vibrational modes of the studied ferrite were investigated in detail. Lattice parameters, bond lengths, compressibility, and bulk modulus for both the cubic and orthorhombic phases of CoFe 2 O 4 were determined.

Some features of the recent seismotectonic activity manifestation within the Soligorsk mining region are considered. A map showing the seismodynamic events recorded in the Soligorsk mining region within 1983–2021 was created. A comprehensive method based on long-term monitoring of seismic events was used to describe the recent seismogeodynamic activity manifestation in the region. It was established that the earthquake arrangement along the fault lines was non-uniform in space and time. The investigations performed were used to determine the seismotectonic potential of seismically active fault zones in the Soligorsk mining region.

A promising area of application of micro- and nanosized magnetic particles is the creation of magnetorheological materials in which such particles are a component of a complex dispersed phase. Of greatest importance is the high shear stress in suspensions based on magnetic particles when a magnetic field is applied, as well as low value of the coercive force. The aim of the work was to study the structure, morphology, and magnetic properties of barium aluminoferrite powders, and to evaluate their effectiveness in magnetic fields by the rheological properties of magnetorheological fluids fabricated using them. Barium aluminoferrite BaAl 2 Fe 10 O 19 of hexagonal structure was synthesized by the citrate sol-gel method. Using the methods of X-ray phase analysis, scanning electron microscopy, IR spectroscopy, magnetometry, its structural and microstructural features, and magnetic properties were studied. The powder had a maximum specific magnetization M = 20.4 A × m ² /kg and a coercive force H c = 4.8 kOe (at 300 K). The high shear stress (3.5 kPa) at a relatively low magnetic field induction (625 mT) makes it possible to consider the resulting material as promising for use as an additional functional filler for magnetorheological fluids.

Four model bioanalytical systems specific for Salmonella enterica have been developed and studied, in which a polymerase chain reaction (PCR) produced a DNA amplicon containing biotin and fluorescein residues. This enabled to immobilize the amplicon on a functionalized solid phase and to label it biospecifically with europium chelate in microplates or gold nanoparticles on a chromatographic membrane. Quantitative detection of the modified DNA was carried out in immunoassay systems by measuring the Eu ³⁺ time-resolved fluorescence (dissociation-enhanced lanthanide fluorescence immunoassay, DELFIA) or by photometry of the colored zone on the chromatographic strip (LFA). Three pairs of primers were developed and examined to obtain selected fragments of the invA gene, which is present in the genomes of all pathogenic Salmonella enterica . The fragments proved to be suitable for the test systems. In the microplate DELFIA system, the concentration range of DNA amplicon quantification was found to be 0.01–10.0 nM, and a detection limit was 2 pM. The limit of DNA visual detection in LFA was 0.05 nM. The possibility of testing the amplicons without additional isolation of pure DNA from the reaction mixture was demonstrated. The high specificity of the developed bioanalytical systems for the detection of various Salmonella enterica serotypes was demonstrated.

The gut microbiota plays an important role in the formation of the body’s regulatory systems (nervous, endocrine, immune), which is especially important at an early age. Hence, gut dysbiosis can lead to an impaired development of both the intestinal microbiota and these regulatory systems. Prebiotics can have a positive effect on the development of the intestinal microbiome, which can correct negative changes. The aim of this study is to investigate the features of development of antibiotic-associated dysbiosis in the early postnatal period in rats and to evaluate the effect of 2′-fucosyllactose in health and during dysbiosis. The study was conducted on Wistar rats aged 12–26 days. To develop dysbiosis at an early age, the following mixtures were used: a mixture of ampicillin trihydrate 75 mg/kg and metronidazole 50 mg/kg and a mixture of amoxicillin 30 mg/kg and cephalexin 20 mg/kg for three days, starting on the 12th day of life. As a prebiotic 2′-fucosyllactose at a dose of 1 g/kg was used, starting on the 12th day and to the last experiment day. In healthy animals, there is a decrease in the gut content of Bifidobacterium spp . and Enterococcus spp . at the age of 26 days. A mixture of ampicillin trihydrate 75 mg/kg and metronidazole 50 mg/kg leads to gut dysbiosis – growth suppression of bifidobacteria, lactobacilli and enterococci. After the end of antibiotics application and continued lactation, the titer of the described bacteria is restored. 2′-fucosyllactose has an effect on the preservation of the titer of Bifidobacterium spp . and Enterococcus spp . , both in healthy animals and after early dysbiosis. Our results indicate that antibiotic-associated dysbiosis at an early age is characterized by a temporary but powerful effect. At the same time, the use of 2′-fucosyllactose leads to preserving important probiotic groups of intestinal bacteria, both in health and after dysbiosis.

Nanoparticles of corn prolamine protein zein (NPQ) containing 0.005–0.26 g/g quercetin (Q) were prepared by desolvation of a 25–30 mg/mL ethanol protein solution containing the encapsulated compound with an aqueous polystyrene sulfonate. The size of zein nanoparticles and their aggregates was characterized by dynamic light scattering and atomic force microscopy; the quercetin content – by the Folin-Ciocalteu assay. While the quercetin/zein ratio in solution is less than 0.08 g/g, the polyphenol is quantitatively included in the nanoparticles, and their hydrodynamic diameter is 60–75 nm. As the quercetin/zein ratio rises to 0.20 g/g, the average particle diameter increases to 150 nm. In concentrated dispersions, aggregates with a diameter of 500–600 nm are formed. The kinetics of quercetin release from NPQ with different mass fractions of Q in distilled water and solutions simulating the environment of the stomach and intestines at 37 °C were studied. Zein nanoparticles exhibit weak activity in the reaction with ABTS cation-radicals. Quercetin encapsulated in the zein matrix generally retains the antiradical activity characteristic of the free flavonoid, however, the rate of decolorization of ABTS cation-radicals decreases due to the prolonged release of quercetin from NPQ. The cytoprotective properties of quercetin in zein nanoparticles are significantly reduced and manifest themselves only in partial preservation of the integrity of cell membranes and a decrease in the release of lactate dehydrogenase from UV-C irradiated HaCaT cells. In contrast to free quercetin, the introduction of Q in zein nanoparticles or their submicron aggregates increases the number of metabolically dead UV-C-irradiated HaCaT cells, enhancing the cytotoxic effect of UV radiation. Empty zein aggregates of submicron size have a similar effect.

The research on the impact of gamification on labor productivity, the level of employee engagement, the recruitment process, as well as the degree of assimilation of information during adaptation and training is analyzed. Due to the insufficient number of publications on gamification as a tool for staff motivation, proposals are made for its use in the activities of business entities in the agricultural sector. An algorithm for the implementation of this concept in the practice of organizations, including agricultural ones, is presented.

The author's mechanism for organizing a mutual investment fund by the Belgospischeprom concern is proposed based on an algorithm that includes nine stages (accreditation of the concern as a management company; decision-making on the formation of a mutual investment fund and approval of a joint investment declaration and rules; registration of investment units; their acquisition by contributions to a mutual investment fund; completion of its formation and reflection information in the depository; selection of investment projects; their financing and implementation; evaluation of results; payment of dividends to participating organizations), of which the first five relate to the creation of a mutual investment fund, the subsequent ones relate to its direct operation.

The results of theoretical research are stated and practical developments concerning the functioning of the institution of mediation (third parties) in the labor market, identifying the features of its agricultural segment, the role in ensuring effective employment of labor resources are presented. It is proposed to solve personnel problems through the creation of centers for the development of professional competencies for largecommodity agricultural production in the context of the development of scale land management, agricultural cooperation and integration, the development of innovations and digital transformation