The article investigates the influence of hydrolysis conditions and working solution composition on the formation and protective performance of acrylate trialkoxysilane-based organosilicon coatings. The study employed functional trialkoxysilanes with various acrylate substituents and steel substrates used for coating deposition. The coatings were prepared using organosilane solutions obtained through acid hydrolysis. The process of hydrolysis was monitored via thin-layer chromatography using silica gel plates. The morphology and elemental composition of the resulting coatings were characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The protective performance was evaluated using Akimov’s drop test. The research focused on the effects of medium acidity, working solution concentration, and ethanol addition on the hydrolysis and formation of a siloxane layer via metal–oxygen–silicon bonds. The highest hydrolysis efficiency was observed at pH 3, resulting in stable solutions and uniform coatings. The optimal organosilane concentration was found to range from 4% to 7%, which yields the highest degree of uniformity. A correlation was established between hydrolysis conditions, coating morphology, and corrosion resistance. Coating deposition was found to extend the corrosion induction period compared to untreated surfaces. The superior protective performance is achieved at organosilane concentrations of 4–7% and pH 3. The findings highlight the potential of the investigated organosilanes for developing effective primer coatings.

In this study, we investigate the effect of various solvents on the structural characteristics of graphite oxide synthesized using a modified Hummers method. The resulting graphite oxide samples were dried by both thermal treatment and freeze drying. Sample characterization was performed using X-ray diffraction, infrared and ultraviolet spectroscopy, scanning electron microscopy, dynamic light scattering, and photon correlation spectroscopy. The content of oxygen-containing functional groups in graphite oxide was determined by Boehm titration. According to the X-ray diffraction data, the use of isopropyl alcohol during the washing stage enabled a more efficient removal of impurities, including unreacted graphite and reduced graphite oxide, than the conventional use of distilled water. Significant differences in the particle size of the obtained samples were observed. The graphite oxide samples washed with isopropyl alcohol exhibited the largest agglomerates in aqueous suspensions (6.5 μm), whereas those washed with dimethyl sulfoxide exhibited the smallest agglomerates (1.2 μm). Boehm titration revealed that the graphite oxide sample washed with isopropyl alcohol contained the highest concentration of carboxyl and lactone groups among all the samples, which agreed well with the infrared and ultraviolet spectroscopic data. The use of different washing solvents enables the production of graphite oxide with different morphologies, which may be advantageous for the development of materials with tailored mechanical and sorption properties. The results obtained suggest that isopropyl alcohol may serve as a promising alternative to distilled water during the washing stage of graphite oxide synthesis. Its application may offer new opportunities for optimizing the graphite oxide production process and its subsequent functionalization.

The article reviews the use of plant extracts in bakery formulations to improve the physical, chemical, and sensory properties of finished products. The growing demand for functional foods has expanded the range of breads enriched with bioactive additives. Plant-derived materials are particularly suitable for this purpose, and extraction enables the recovery of their most valuable constituents. The review summarizes documented health-related benefits of incorporating plant extracts into bread formulations. Their effects in breads, rolls, and low-moisture bakery products, such as crispbreads, rusks, and breadsticks, are described. Plant extracts can increase the nutritional and biological value of gluten-free products, reduce starch digestibility, which is a relevant attribute for individuals with diabetes, improve gastrointestinal function, and lower acrylamide levels in finished products. Their addition to bread and rolls improves dough rheology, accelerates fermentation and maturation, and strengthens gluten networks. It also increases loaf-specific volume while enriching products with macro- and microelements, vitamins, and phenolic compounds. In low-moisture products, extracts rich in phenolic compounds enhance antioxidant activity, extend shelf life, and reduce microbial counts. These findings indicate that plant extracts are promising functional additives for bakery applications.

The expanding applications of cellulose nitrates require new precursors, such as high-viscosity cellulose materials. High viscosity enables the production of a wide range of cellulose nitrates grades demanded by various sectors in industry and medicine. In this regard, giant miscanthus is considered a low-cost perennial feedstock with high potential for chemical conversion. In this study, cellulose samples with a degree of polymerization of 1600–1890 were isolated from miscanthus (cellulose mass fraction of 49.4–52.8%) cultivated in the Moscow, Kaluga, and Penza regions of the Russian Federation. The yield of cellulose samples was 34% relative to the raw material (64% of native cellulose). The resulting cellulose samples exhibited high quality, with the mass fraction of α-cellulose reaching 93.8–96.6% and the non-cellulosic components accounting for 2.90–4.22%. A comparison with published data on the quality of cellulose from various raw materials indicates that giant miscanthus holds a leading position in terms of the degree of polymerization. Thus, this study demonstrates the feasibility of producing high-quality cellulose with an ultra-high degree of polymerization (up to 1890) from the stems of giant miscanthus. The high α-cellulose content and degree of polymerization of cellulose from domestic giant miscanthus ensure the necessary strength, thermal stability, film-forming ability, and protein affinity of cellulose nitrates, comparable to those of imported cotton cellulose.

This study characterized the protein quality of pea protein isolate and the secondary starch-protein concentrate obtained by enzymatic hydrolysis using enzyme preparations developed in Russia. The amino acid composition of the samples was determined by high-performance liquid chromatography with post-column ninhydrin derivatization on an LC-20 Prominence system (Shimadzu, Japan). Amino acid score and protein quality, expressed as the protein digestibility-corrected amino acid score (PDCAAS), were calculated according to the Food and Agriculture Organization / World Health Organization guidelines (2011). In vitro protein digestibility was assessed using the method of A.A. Pokrovsky and I.D. Ertanov. Seventeen amino acids (tryptophan not accounted for), of which eight were essential, were identified in both the enzymatically hydrolyzed isolate and the secondary starch-protein concentrate. The total (884.65 mg/g) and essential (327.74 mg/g) amino acid contents of the hydrolyzed isolate were 4.52–4.66 times higher than those of pea flour and 9.83–16.39% higher than those of the isolate obtained by conventional alkaline extraction. The amino acid score of the hydrolyzed isolate ranged from 87% to 174%. Its digestibility and protein quality (PDCAAS) were 98.92% and 0.86, respectively, which is 5.64–7.50% higher than the corresponding values for pea flour and 3.62–10.55% higher than those for the alkaline-extracted isolate. Proteins of the starch-protein product exhibited the highest proportion of essential amino acids relative to total amino acids (40.55%), with an amino acid score of 112–197%, digestibility of 96.27%, and a protein quality value of 1.00, indicating high quality of the product. These findings support the development of food products enriched with high-quality plant proteins.

The accumulation of wood-processing waste is a significant environmental challenge due to the heterogenous composition of biomass and the limited economic viability of its recycling. In this regard, biological composting of wood waste using basidiomycetes represent a promising direction. However, the implementation of such methods requires substantial amounts of viable fungal mycelium. In this study, we investigate the kinetics of mycelial growth and biomass accumulation under both stationary and dynamic conditions of submerged cultivation for five fungal strains isolated from decaying wood in Eastern Siberia and used for recycling wood waste: Paecilomyces variotii sp. Irk 52, Phanerochaete chrysosporium Irk 2, Phanerochaete chrysosporium Irk 10, Sporotrichum pulverulentum Irk 1766, and Sporotrichum pulverulentum Irk 1767. Basidiomycete strains exhibited significantly higher radial growth rates on solid agar media than Paecilomyces variotii. In contrast, cultivation in liquid nutrient media produced the opposite trend, likely due to species-specific variations in colony morphology. The evaluation of cultivation conditions identified a glucose–yeast medium and submerged cultivation under dynamic conditions as the most effective approach. Under these conditions, the investigated strains achieved high biomass yields ranging from 6.3 to 8.3 g/L. Growth kinetics, glucose consumption patterns, and culture medium pH dynamics under the selected cultivation regime were examined. During semi-industrial cultivation, the optimal aeration rate and mixing intensity were determined to be 1.0–1.3 L/(L·min) and 0.3–0.5 m/s, respectively. These findings enabled the selection of strain-specific cultivation parameters, thus forming a basis for scaling up the biotechnological production of viable fungal mycelium.

Most models describing the effect of light on the growth rate of optically dense microalgal cultures rely on the classical Beer–Lambert–Bouguer law, and the mismatch between theory and experiment is typically compensated by introducing empirical correction factors. Although these factors reflect the increase in light scattering as culture density rises, they offer no biological interpretability. As an alternative, an analytical model is proposed that describes the spatial distribution of photon flux within a microalgal culture. Rather than invoking the physics of absorption and scattering in colloidal media, the model is grounded in the experimentally observed linear growth of microalgae: photon flux density decreases hyperbolically with increasing biomass concentration and exponentially with increasing optical path length. To validate this approach, Tetraselmis viridis was cultivated in batch mode in photobioreactors with various biomass layer thicknesses under identical surface irradiance. Under all experimental conditions, the cultures exhibited an extended linear growth phase characteristic of light limitation. Relationships were obtained between transmittance, optical path length, and biomass concentration. The experimental data were fitted using both the proposed analytical model and the Beer–Lambert–Bouguer law; each provided adequate accuracy. A quantitative relationship was derived linking the productivity of Tetraselmis viridis in the linear growth regime to the biomass layer thickness. These expressions apply only under light-limited conditions. The modeling results indicate that the proposed theoretical framework is appropriate and has both scientific and practical value, particularly for predicting Tetraselmis yield in industrial-scale cultivation.

This study aims to obtain new multifunctional hemostatic materials with a broad spectrum of biocidal properties and to evaluate their hemostatic and antibacterial characteristics. The materials are synthesized by modifying oxidized natural polysaccharides (cellulose and starch) with the synthetic linear polyhexamethylene guanidine hydrochloride (PHMG-HCl). The resulting composites demonstrate pronounced hemostatic activity together with enhanced antibacterial properties. Scanning electron microscopy showed that the particle sizes of the oxidized polysaccharide powders and their complexes with the polycationic polymer ranged from 3×10 to 20×50 μm. The strongest hemostatic effect was observed for the composite based on oxidized starch and PHMG-HCl. In vivo experiments demonstrated a fivefold reduction in blood clotting time, while in vitro tests showed a 1.5-fold decrease in bleeding time and a threefold reduction in blood loss compared with oxidized cellulose. The oxidized starch– PHMG‑HCl composite also exhibited antibacterial activity against multidrug‑resistant strains of Escherichia coli and Bacillus cereus. These composite materials can be considered promising multifunctional hemostatic agents with a broad biocidal spectrum for controlling bleeding associated with traumatic injuries in extreme conditions and during surgical procedures.

Reliable assessment of activated sludge condition during extended aeration treatment of industrial wastewater requires indicators that respond rapidly and sensitively to changes in biological performance. Enzymatic activity is a promising option; however, its applicability must be validated experimentally. This study examines the effects of several technological factors, including sludge age and regeneration conditions, on catalase activity. Catalases were selected as the target enzymes, as dehydrogenases exhibit low activity under extended aeration and are readily inactivated by toxic contaminants. These properties prevent consistent dynamic measurements in mature sludge. By contrast, catalases are key components of the cellular defense system that detoxify excess hydrogen peroxide generated when activated sludge is stressed by adverse environmental factors or variations in bioreactor operation. Their higher expected sensitivity was confirmed experimentally. The results show that catalase activity decreases as sludge age increases. Comparative analysis demonstrated that non-regenerated sludge samples consistently exhibited lower catalase activity than corresponding regenerated samples, regardless of the configuration of the regeneration unit. Sludge formed in systems with separate regeneration tanks showed a more pronounced reduction in catalase activity.

Deep eutectic solvents have attracted considerable attention in the field of plant biomass pretreatment due to their environmental friendliness and tailorable properties. This study aims to evaluate the impact of ultrasound-assisted treatment on wheat straw conversion efficiency during thermal exposure in a deep eutectic solvent. For this purpose, a deep eutectic solvent comprising triethylammonium chloride and oxalic acid (1:1 molar ratio) was employed. The straw/ solvent mixture (1:20 mass ratio) underwent combined treatment at temperatures of 90, 100, 110, and 120°C for 10 min. Ultrasonication was applied at a frequency of 44 kHz and a power of 50 W. Increasing the treatment temperature within the range of 90–120°C was found to facilitate the removal of lignin and hemicellulose from the straw biomass. Specifically, treatment at 120°C yielded 64.2% delignification of the straw and 67.5% hemicellulose removal. Under the treatment conditions, cellulose was more resistant to hydrolysis than hemicelluloses and lignin, with its hydrolysis not exceeding 15%. Ultrasonication reduced the thermal treatment time to 10 min while enhancing the efficiency of cellulose enzymatic hydrolysis. For the technical cellulose fraction isolated at 100°C, the sugar yield reached 40.8% (dry basis). This represents 83% of the theoretical maximum and a 4.5-fold increase compared to the untreated straw.

The disposal of lignin sludge remains one of the most pressing challenges requiring effective solutions to improve the environmental situation in the Baikal region. Lignin sludge is a large-scale waste product generated over long-term operation of the Baikalsk Pulp and Paper Mill and stored in storage ponds on the southern shore of Lake Baikal. To date, numerous technological solutions for recycling the content of these ponds have either not been implemented or proved unsuccessful. The aim of this study was to develop a method for utilizing lignin sludge through thermochemical processing to obtain a modified lignin-containing resole-type phenol-formaldehyde resin. The reasons for the accumulation of this waste, as well as the composition and properties of lignin sludge, are examined. Modified lignin-phenol-formaldehyde resins were obtained in a liquid state by condensing lignin sludge, caustic soda, phenol, and formalin in specified ratios upon heating to 85–95°C for 0.5–1.5 h. The resulting resins were analyzed in terms of viscosity and contents of nonvolatile substances, alkali, free phenol, and free formaldehyde. The most favorable conditions for the synthesis process are determined, and the properties of the modified resins are described. In a number of characteristics, the obtained phenol-formaldehyde resins are comparable to conventional phenol-formaldehyde resins. The proposed method for the synthesis of modified phenol-formaldehyde resins is based on the use of lignin sludge from the Baikalsk Pulp and Paper Mill as a modifying agent, taken directly from storage ponds. The process occurs in a single stage without changing the temperature range. These resins can be used as components in adhesives, fiberglass, sealants, etc.

The study explores the feasibility of enhancing the impact of ultrasonic vibrations on liquid media at elevated temperatures. To intensify processes at the gas-liquid interface through ultrasonic cavitation at temperatures of up to 60–75°C, the functional capabilities of the equipment were investigated. It is shown that generator output parameters must be matched with the oscillatory system, factoring in temperature-induced changes in the medium’s properties to ensure maximum ultrasonic impact. The study of how elevated temperatures affect key equipment parameters helped to establish the optimal matching modes between the generator and the ultrasonic oscillatory system. This enables the application of ultrasonic technology to improve process efficiency in both laboratory and industrial settings. Empirical results confirm that the gas-liquid interfacial area in viscous media can be increased by reducing the attenuation of capillary waves as the temperature rises. The findings validate the practical application of ultrasonic technologies as an intensifying factor at elevated temperatures. This approach ensures maximum intensification of processes occurring in liquid media during cavitation at temperatures of 55–75°C and intensities starting from 15 W/cm², which opens new prospects for optimizing technological processes.

This study investigates the effect of different oil concentrations on the critical micelle concentration of the following surfactants: sodium dodecyl sulfate as an anionic surfactant, Tween 80 as a nonionic surfactant, and cetyltrimethylammonium bromide as a cationic surfactant. The critical micelle concentration was determined from abrupt changes in solution turbidity and specific electrical conductivity. The addition of oil (10–50 mg/L) was shown to alter the critical micelle concentration. For sodium dodecyl sulfate, the critical micelle concentration decreased at low oil concentrations and increased at higher oil concentrations. For cetyltrimethylammonium bromide and Tween 80, a consistent shift of the critical micelle concentration toward higher concentrations was observed. The results indicate that oil may act as a co-surfactant or hydrophobic additive influencing micellization processes. Specifically, oil can increase the surfactant concentration required to initiate self-assembly by stabilizing oil-in-water emulsions and modifying the microenvironment of polar head groups (for cetyltrimethylammonium bromide, Tween 80, and sodium dodecyl sulfate at moderate and high oil loading rates). The following practical recommendations are formulated: (1) engineering calculations of surfactant dosages for hydrocarbon solubilization and microemulsion formation should account for a potentially nonmonotonic critical micelle concentration response at low to moderate oil contents, particularly in anionic systems; (2) for ionic surfactants, the ionic strength and hardness of water should be monitored to avoid “disguising” the oil-induced critical micelle concentration shift; and (3) for nonionic ethoxylated surfactants, the presence of oil may increase the surfactant dosage required to achieve micellization. The findings are of practical significance for both the development of bioremediation technologies for oil-contaminated ecosystems and enhanced oil recovery.

The mitochondria of major taxonomic groups possess the ability to import DNA from their environment; however, the cellular role of this process remains not fully understood. Collectively, all mitochondria within a cell form the chondriome, whose structure is crucial for organelle interactions and maintenance of cellular homeostasis. No data are currently available regarding the impact of altered mitochondrial fusion and fission dynamics – which leads to the structural disruption of the chondriome – on DNA import into mitochondria. This study aimed to examine the relationship between chondriome structure and the import of foreign DNA into mitochondria using Arabidopsis knockout lines characterized by impaired fusion and fission processes (drp3, friendly). Inactivation of the mitochondrial fission protein isoform DRP3B, which leads to the formation of highly elongated mitochondria, reduced the import activity of a 2.7 kb fragment. Mitochondrial clustering, characteristic of the friendly knockout mutant, also led to a decrease in the import level of this fragment, while the import activity of a short DNA fragment (0.27 kb) remained unchanged. Thus, the normal functioning of the mechanism responsible for importing larger DNA fragments requires maintaining a balance between mitochondrial fusion and fission. The observed correlation between DNA import activity and changes in chondriome structure provides new insights into the role of DNA import and its contribution to cellular stability.

This study examines a tandem heterocyclization of azines using carbonyl compounds and 3-aminophenol, which affords a potentially bioactive heterocycle. Condensation of equimolar amounts of 2-acetonaphthone with dibutyl oxalate in the presence of sodium, followed by treatment of the reaction mixture with acetic acid and subsequent addition of 3-aminophenol, enabled the preparative-scale synthesis of a new 7-hydroxy-4-(2′-naphthyl) quinoline-2-carboxylic acid. The structure of the isolated compound was confirmed by infrared spectroscopy, ¹H and ¹³C nuclear magnetic resonance spectroscopy, and high-resolution mass spectrometry. Interpretation of the infrared spectrum revealed broadened, intense absorption bands attributable to the phenolic O–H group and the hydroxyl group of the carboxyl moiety, along with a characteristic C=O stretching band. The ¹H nuclear magnetic resonance spectrum recorded in deuterated dimethyl sulfoxide (DMSO-d₆) exhibited the expected multiplet, doublet, and singlet resonances of the aromatic protons. A downfield broadened singlet corresponded to the protons of the phenolic and carboxylic hydroxyl groups. The ¹³C nuclear magnetic resonance spectrum in deuterated dimethyl sulfoxide (DMSO-d₆) revealed downfield signals for the carboxyl carbon (COOH) and the C⁷–OH carbon. Electrospray ionization mass spectrometry (in acetonitrile containing a small amount of dimethyl sulfoxide) corroborated the proposed structure, showing the [M+H]⁺ and [M+Na]⁺ ions. The developed approach allows structurally diverse, potentially bioactive 4,7-disubstituted quinoline-2-carboxylic acids to be synthesized by varying the starting methyl ketones and nucleophiles.