Today, a significant part of the world’s population lives in urban agglomerations. A high building density, a large number of vehicles, and industrial enterprises negatively affect both the air quality in the city itself and the climate in general, releasing a significant amount of carbon dioxide. In this regard, there is a need not only to revise the structure of urban developments and strategies for their greening, but also to propose new technologies that radically change the ecological situation. In this paper, solutions using phototrophic microorganisms are considered as such a technology. It is shown that photobioreactors for their cultivation can be successfully integrated into urban systems, while in addition to air purification, the problem of surface wastewater treatment for their further use can also be solved. A wide range of products obtained from the biomass of phototrophic microorganisms significantly increases the economic attractiveness of this approach. Modern technologies in the field of the Internet of Things make it possible to successfully integrate photobioreactors into the urban digital environment.

Microbial fuel cells are beginning to be widely used to solve various applied problems; in the last decade, considerable attention has been paid to photobiofuel cells (PBFCs), in particular, biofuel cells with a photocathode. Information on the current state of research in the field of PBFCs is presented. The application of these devices, namely, systems for treating various types of wastewater with electricity generation, power-supply systems for distributed sensors, and systems for urban and park illumination, is shown. Special attention is given to ways of PBFC integration into existing surface wastewater-treatment systems and urban systems such as rain gardens. The main materials used for PBFC electrodes and membranes are considered. It is shown that various types of carbon materials from graphene and carbon nanotubes to activated carbon are widely used, since they generally meet the requirements for PBFC electrodes. It is noted that it is necessary to develop methods for analyzing the efficiency of the immobilization of microorganisms over the entire electrode, but not for its individual sections. PBFCs are a promising technology that will be widely used in urban economy in the near future.

Antibacterial biocomposites based on bacterial cellulose, chitosan, and fusidic acid are obtained in the form of films, hydrogels, and aerogels. The structure of the composites is studied by atomic-force- and scanning-electron microscopy, infrared (IR) spectroscopy, and computed microtomography. It is shown that the thickness of bacterial-cellulose fibers formed by the strain Komagataeibacter sucrofermentans B-11267 on a molasses medium is 50–60 nm. The synthesized nanocomposites exhibit high antibacterial activity against the gram-positive bacteria Staphylococcus aureus and Bacillus lichenoformis and can be used in medicine as tissue-engineering materials and antibacterial wound dressings.

The development of alternative energy sources is one of the most important areas of modern science. The processes of energy generation are studied in a membraneless mediatorless microbial fuel cell fueled by the Gluconobacter oxydans microorganism using synthetic wastewater with phototrophic Chlorella vulgaris microalgae in the cathode chamber. The operation of the fuel cell is compared with different catholytes, including microalgae with and without illumination, a nutrient medium for growing microalgae, and a K-phosphate buffer. This microbial fuel cell shows stable operation with a slight decrease in power over 113 days of the experiment. This result is due to the formation of biofilms and is confirmed by scanning-electron-microscopy images. Thus, the studied microbial fuel cell is promising for further study in the field of wastewater treatment.

Phototrophic microorganisms are considered one of the promising sources of renewable raw materials that can be used to produce energy and a variety of valuable products. Studies on the cultivation of microalgae Chlorella vulgaris GKV 1 in horizontal-type photobioreactors using a hydrogel with titanium-dioxide nanoparticles 84 ± 20 nm in size and adaptive illumination are carried out. The productivity of the microalgae C. vulgaris using a hydrogel with nanoparticles and adaptive illumination exceeds the control by 53.4%. The lipids of the obtained biomass are analyzed for the qualitative composition of methyl esters of fatty acids. The polymer material is studied at the Kurchatov specialized source of synchrotron radiation (KISI-Kurchatov).

C-phycocyanin, being a component of the photosynthetic apparatus of cyanobacteria, is an effective antioxidant and anti-inflammatory agent and is often used in medical studies. The intracellular effect of C-phycocyanin isolated from cyanobacteria Arthrospira platensis on the levels of the prooxidant-induced oxidative stress and cell death of the aerobic yeast Yarrowia lipolytica is considered. We show that C-phycocyanin accumulated in the yeast cells and had a direct antioxidant effect on the yeast suspension within the concentration range of 10–100 μg/mL and a cytotoxic effect with a further increase in concentration. The effect of C-phycocyanin in the most effective concentration is comparable to the antioxidant effect of the mitochondria-targeted cation SkQ1.

NETosis is a form of neutrophil death in which DNA, chromatin, and bactericidal proteins of granules are secreted into the extracellular space and form a network in which pathogenic microorganisms die. The induction of NETosis by small molecular substances (sphingosine, fingolimod, stearylamine, stearic acid, ceramide) is studied. Fluorescence microscopy reveals that sphingosine induces NETosis in a primary culture of human neutrophils within 60 min. Compared with the classic NETosis inducer, phorbol 12-myristate 13-acetate, sphingosine-induced NETosis can be classified as “rapid.” Stearylamine and fingolimod are significantly less active. Ceramide and stearic acid do not enhance NETosis compared with the control. It is found that blocking NADPH oxidase with apocynin and DPI and inhibiting protein kinase C with chelerythrine do not affect the formation of traps under the action of sphingosine. Using the method of chemiluminescence, it is revealed that sphingosine and other studied compounds suppress the oxidative burst of neutrophils induced by phorbol 12-myristate 13-acetate and latex. The results obtained allow us to conclude that sphingosine, stearylamine, and fingolimod induce the development of such a type of NETosis, which is not associated with the activation of NADPH oxidase and develops according to a mechanism different from that of NOX-dependent NETosis development.

We describe the dynamics of lipoic acid (LA) alone, incorporated in liposomes and as a part of nanoemulsions. Mass spectrometry shows that LA in water forms aggregates of two or three molecules in the form of a negatively charged ion and a neutral molecule. Phosphatidylcholine (PC)-based nanoforms of LA as liposomes and nanoemulsions with a particle size equal to 145 nm are characterized by a high degree of incorporation of LA into the nanoparticles and long-term stability during storage at room temperature. Dynamic light scattering (DLS) gives the polydispersity index of the nanoforms (> 0.3), characterizing the homogeneity of the obtained nanodispersions. We found that such emulsions can significantly (5 ×) increase the concentration of LA in the aqueous phase (5–7 mg/mL) when compared with an aqueous solution of LA (1 mg/mL) and by 40% when compared with PC liposomes (4 mg/mL). Moreover, the inclusion of LA in liposomes and nanoemulsions from PC did not change the neutral ζ-potential characteristic of PC nanoforms. CryoTEM established that the structural organization of the liposomes practically did not differ from nanoemulsions and both nanoforms contained both multilayer and single-layer vesicles. When studying the release kinetics of LA from phosphatidylcholine nanoforms, we found that at 22 h, 45–55% of LA was released from nanoparticles, but that at the initial stage of the process LA was slowly released from the nanoemulsions and rapidly from the liposomes. Conductance measurements indicate that LA delivered in all the three forms increase membrane permeability, though this result is most marked with the LA in PC liposomes.

The conditions for the preparation of astaxanthin ester aggregates are optimized, and their physicochemical characteristics (size and absorption spectra) are found depending on preparation conditions. The monoester and diester fractions were isolated via column chromatography from a mixture of astaxanthin esters. An aqueous mixture of methanol and tetrahydrofuran is used for the first time to obtain aggregates, so that it is possible to obtain J-aggregates of astaxanthin monoesters and diesters, which are detected with spectrophotometry. The change in the position of a the equilibrium monomer ↔ aggregates reaction is found during storage for a month. The effect of ionic strength on the formation of astaxanthin ester J-aggregates is studied.

Astaxanthin and its esters, which are classified as secondary carotenoids, are synthesized under stress conditions in Haematococcus pluvialis cells that undergo transformation from vegetative cells to hematocysts. Stress factors can affect not only the rate and the direction of synthesis, but also the conformational changes in the pigment molecule, causing conversion of trans -isomers to cis -isomers. The aim of this study was to evaluate the effects of different factors (the polarity of the medium and light) on the process of trans – cis isomerization of astaxanthin. Investigation of the formation of 9- cis - and 13- cis -isomers from all-trans astaxanthin solutions at 50°C showed that medium polarity solvents stabilized cis -isomers more efficiently than highly polar solvents. Nonpolar solvents did not contribute to the stabilization of cis -isomers. The presence of π-bonds in the solvent molecule also stimulated isomerization. Analysis of the effects of the solvent refractive index on polarizability of astaxanthin revealed differences between the dependencies for polar and nonpolar solvents. Supposedly, solvents of medium polarity facilitate the process of trans – cis astaxanthin isomerization by decreasing the energy of the torque and stabilizing the cis -conformation of the molecule due to diminished dipole–dipole repulsion between the methyl groups in the polyene chain and the ionone ring. Exposure of astaxanthin solutions to light at 25°C induced formation of cis -isomers, which were more abundant within the first 4 h of exposure than after 6 h or later. Exposure to irradiation for longer periods caused astaxanthin decomposition and formation of degradation and oxidation products.

An overview of the current state of production technologies of biojet fuels in the world and in Russia is presented. The contribution of the aviation sector to climate change processes and the likelihood of achieving global environmental goals in the event of large-scale production of alternative aviation fuels are assessed. The level of commercialization, constraining factors and possible measures to support synthetic kerosene production technologies are reviewed. Special attention is paid to the current international certification procedure for aviation biofuels. aviation biofuel, biojet fuels, synthetic kerosene, global warming, climate change, greenhouse gases emission, sustainable biofuel, ASTM certification, biomass conversion, photosynthetic microorganisms, microalgae. The review was financially supported by the Ministry of Science and Higher Education of the Russian Federation, project no. 14.574.21.0139 (Unique Project Identifier RFMEFI57417X0139).

The structure of the ATP synthase of rat’s heart mitochondria is determined by cryoelectron tomography (cryo-ET). The experiments are carried out on fragments of mitochondrial membranes without the additional purification of samples, which allows us to study the mitochondrial enzymes in the natural phospholipid and protein environment. The use of subtomographic averaging yields the structure of the ATP synthase with a resolution of about 13 Å, as well as the structure of a stable dimer of ATP synthases with a resolution of about 15 Å. The classification of the obtained subtomograms containing ATP synthases showed that this enzyme is always located on the bends of the phospholipid bilayer, while there are two groups of ATP synthase dimers that differ in the membrane curvature in the regions of their localization. On the obtained three-dimensional structures, both extramembrane and intramembrane synthase subunits are quite clearly distinguishable, which indicates the prospects of the chosen methodological approach for studying polyenzyme systems in the natural environment.

The article considers key Biotech trends for thermal power engineering, in particular in wastewater treatment, flue gas cleaning, remediation of ash and slag disposal sites and oil-contaminated soils. An overview of key technological solutions in these areas is provided. Special attention is paid to phototrophic microorganisms application for CO2 fixation. List of possible products that can be obtained from these microorganisms is given. The latest data about lipids (main component for biodiesel production) productivity from different strains in different conditions are presented. Also, other possible applications of phototrophic microorganisms in combination with carbon dioxide fixation (biological pre-treatment and biodesalination) are shown. Aquaporin based reverse osmosis membranes are discussed. It is shown that today the introduction of such technologies becomes economically feasible, especially in the case of flue gases from thermal power plants used for the cultivation of phototrophic microorganisms to further obtain a wide range of products including pharmaceutical substances, biofuels and animal feeds.

Neutrophils can form extracellular traps that consist of chromatin and granule proteins and can, acting as a net, trap bacteria. The trap formation process called NETosis that has been thoroughly characterized in cells exposed to phorbol ester (PMA) takes 2–3 h and depends on reactive oxygen species produced by NADPH oxidase (this is called classical NETosis). The aim of the present work was to study the distinctive features of the NETosis process evoked by stearylamine (SA) dissolved in DMSO or incorporated into phosphatidylcholine (PC) liposomes and to compare it to NETosis evoked by PMA. Human neutrophils were incubated with 0.2 mg/mL SA (at a 2% DMSO content in the medium) or with cationic PC liposomes that contained SA (PC–SA liposomes; PC and SA concentrations 1.8 and 0.2 mg/mL, respectively). Confocal fluorescence microscopy of fixed neutrophil preparations showed that SA (dissolved in DMSO or incorporated into liposomes) caused the formation of neutrophil extracellular traps. NETosis kinetics were analyzed in the real-time mode in live cells exposed to fluorescently labeled PC–SA liposomes. PC–SA liposomes added to the neutrophils were shown to adsorb to isolated patches of the plasma membrane at first and to occupy the entire membrane surface as the incubation time was prolonged. This was accompanied by chromatin decondensation and fusion of the nuclear material and the cytoplasm, that is, the stages observed for phorbol ester-induced NETosis. However, SA-evoked NETosis was much faster (30–90 min) than PMA-evoked NETosis. It is necessary to emphasize that SA did not induce an oxidative burst (in contrast to PMA), as revealed by analysis of luminol-dependent chemiluminescence. Trap formation by neutrophils exposed to PC–SA liposomes was not affected by apocynin and DPI (NADPH oxidase inhibitors) or catalase, and this also shows that SA stimulates ROS-independent formation of neutrophil extracellular traps.

This paper examines the effect of electromagnetic waves, with maxima in the green or red regions of the spectrum, on the morphofunctional state of multipotent mesenchymal stromal cells. The illumination regimes used in our experiments did not lead to any substantial heating of the samples; the physical parameters of the lighting were carefully monitored. When the samples were illuminated with a green light, no significant photostimulatory effect was observed. Red light, on the other hand, had an evident photostimulatory effect. It is shown that photostimulation with a red light decreases the enzymatic activities of mitochondrial dehydrogenases and enhances the viability of cells, their proliferative activity, and their ability to form bone tissue. It is also established that red light stimulates cell proliferation, while not activating the genes that increase the risk of the subsequent malignant transformation of cells or their death. This paper discusses the possible role of hydrogen peroxide in the processes examined.

The article analyses the contradiction between the high biomass resources and low level of bioenergy utilization in Russia. The article presents the total estimation of bioenergy potential of Russia in comparison with the real utilization rate and with the bioenergy potential of other countries. The study gives the analysis of general bioenergy regulating policy in Russia and describes the key objectives of Russian bioenergy community. The authors of this paper made a preliminary evaluation of the technical bioenergy potential of Russia. It was estimated at 2225.4 PJ. Crop residues contribute 42% of the total potential while livestock waste contributes 9%, forest residues 23%, municipal solid waste 25% and biogas from sewage sludge 1%. Only 12% of the bioenergy potential of Russia is being currently utilized. To the extent of the authors’ knowledge, this paper is the first attempt to compare the existing bioenergy potential of Russia to the level of its actual use. The technical bioenergy potential is equal to 30% of today's total heat and electricity consumption in Russia. At the same time in some regions the technical bioenergy potential exceeds the existing heat and electricity consumption. Considering the world bioenergy potential to be assessed in the range between 64 and 161 EJ, Russia accounts for 1.3–3.5% of it.