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Respiratory system diseases are among the most dangerous for human life. Pathologies of the respiratory system appear due to environmental pollution, the spread of epidemics, etc.. To predict the course of pathological processes, the body's response to various influences of external extreme conditions, there is a strong need to develop the imitational mathematical models, which can provide the opportunity for the fast selection of the necessary optimal breathing mode. The goal of the work was to develop the imitational mathematical model to prognose and regulate the state of the respiratory system of the organism under the indignation of the environment. To study the mechanisms of self-regulation and adaptation of the body to disturbances of the external or internal environment, a mathematical model of the functional respiratory and circulatory system was developed. The dynamics of the partial pressures and stresses of the respiratory gases in the structures of the body was described by a system of ordinary differential equations. The principles of material balance and continuity of the flow were used to construct them. The structure of the model considered several reservoirs of the alveolar space, each of which was connected to the environment by a separate section of the airways and was washed by the corresponding volume of blood in the pulmonary capillaries. On the basis of the mathematical model of the functional respiratory system, an imitational mathematical model of the gas exchange process in the lungs has been developed and investigated. The model took into account the role of the elasticity and the resistance of the lung structures in the formation of the nature of the gas exchange process under various modes of external respiration. The results of the research will allow to accelerate the selection of the optimal breathing mode to achieve a stable balance of the internal and the external environment of the body.

Fossil carbon-containing fuel is currently one of the most common in industry and economy. The rapid depletion of reserves of this fuel makes it necessary to search for the alternative one. Landfills are a place where methane is spontaneously synthesized due to the decay of organic waste. Controlled and regulated fermentation of the landfill organics can provide biomethane as well as environmental bioremediation. The aim of the work was to study the patterns of methane fermentation of multi component organic waste and optimize the process to increase the efficiency of biomethane synthesis and waste decomposition. Colorimetric and potentiometric methods were used for pH and Eh measurement. Volumetric and chromatographic methods were applied to control volume and composition of synthesized gas. Fermentation parameters were calculated with the use of mathematical and statistical ones. The achievement of high efficiency of methane fermentation of organic waste due to the process regulation was shown. The modeling of unregulated fermentation of organic waste in landfills showed low efficiency of the process. It took 69 days. Weight of waste decreased only 5 times. Hydrogen yield was 5 L/kg of waste. Methane was not synthesized. The regular mass transfer, regulation of the process and waste grinding showed the greatest efficiency. Weight of waste decreased 20 times during only 14 days. Hydrogen yield was 27 L/kg, methane yield was 12 L/kg of waste. Thus, the absence of regulation caused long term decay of waste. The high efficiency is achieved due to regulation of the fermentation process. The results will serve as a basis for the development of industrial biotechnology for the utilization of organic waste to reduce the volume of existing landfills and produce methane energy. This will further allow bioremediation of contaminated areas, obtaining an alternative to fossil fuel biomethane.

The environmental pollution by copper and the increasing amount of environmentally hazardous organic waste destroy natural ecosystems and have negative and even lethal effect on living organisms. The chemical techniques of metal containing waste detoxification are expensive and hazardous being the advanced problem today. The aim was to justify theoretically and confirm experimentally the possibility of toxic Cu2+ removal by hydrogen producing microbiome (HPM) via dark hydrogen fermentation of solid multicomponent food waste (MFW). Colorimetric and potentiometric methods were used for pH and redox potential measurement. Volumetric and chromatographic methods were applied to control volume and composition of synthesized gas. Fermentation parameters were calculated with the use of mathematical and statistical ones. The high effectiveness of solid waste destruction and Cu2+ removal was shown by spore forming HPM. The MFW were fastly and effectively digested by the microbiome at the absence of Cu2+. The weight of MFW was 90 times decreased (Kd = 90). The maximum concentration of H2 was 35% and biohydrogen yield was 76 L/kg of MFW counting on absolutely dry weight (ADW). The fermentation process was inhibited by Cu2+ in the form of citrate complex. The biohydrogen yield and efficiency of waste destruction were decreased on 41% (45 L/kg of waste) and 37% (Kd = 57) consequently after addition of 50 ppm Cu2+ to the culture liquid of the bioreactor during the beginning of final phase (50 hours) of MFW fermentation. The effect of complete inhibition of H2 synthesis was obtained in the case of adding 100 ppm Cu2+ to the culture liquid sampled from bioreactor during the final phase (80 hours) of fermentation. Nonetheless, the Cu2+ was bioremoved by HPM with high efficiency up to 99.0 % and 99.5% after 5 hours and 30 hours of fermentation where initially the concentrations of Cu2+ were consequently 50 and 100 ppm. The synthesis of gas was not significantly restored after the addition of Cu2+ in both variants of the experiment. Obtained patterns will be used as a basis for the development of novel universal biotechnologies of metal-containing sewage purification with simultaneous destruction of MFW.

Despite the achievements in development of environmental biotechnologies, the total amount of waste is continuously increasing. Development of novel methodological approach is the only possible effective solution of problems. The aim was to develop the base of universal biotechnologies for effective treatment of all four classes of waste and obtain valuable products. To obtain biotechnologically promising results the method of thermodynamic prognosis of microbial interaction with toxic compounds (multi component food waste and filtrate, metal containing wastewater, radioactive waste) was developed. The following results of food waste degradation were obtained: time detention T=6 days, coefficient of waste destruction Kd=90; biohydrogen yield – 120 L from 1 kg of waste. Wastewater treatment provided purification from 10020 to 20 ppm of total Carbon and toxic metals. Purification of liquid radioactive waste allowed several orders decreasing its activity within 4-5 days. These biotechnologies are promising for their industrial implementation in order to stop pollution of environment and preserve ecosystems.

Despite the promising application of microorganisms for purification of metal-containing wastewater such biotechnologies have not been widely used since their empirical basis. Therefore, the aim of our work was to apply thermodynamic prognosis to determine the optimal pathway of microbial removal of toxic metals (CrO42-, Cu2+) and its experimental justification. There was theoretically substantiated on the base of thermodynamic prognosis and experimentally confirmed integration of microbial reduction of metals, and their precipitation by microorganisms. Developed approach is the methodological basis for fast and effective purification of metal-containing wastewater.

The aim of the work was to develop effective environmental biotechnologies enabling to stop pollution of environment with a wide range of toxicants and transform them into commercially valuable products. Using the method of thermodynamic prediction an algorithm to create new universal environmental biotechnologies was developed. Distinctive features of biotechnologies include: 1). fast and efficient disposal of a wide range of environmentally hazardous waste (decaying food and agricultural waste, synthetic organic compounds, and metal-containing waste water, etc.); 2). increase the efficiency of biotechnologies due to application of selected soil anaerobic microorganisms; 3). obtaining of a wide range of valuable products: gaseous fuels (hydrogen, methane), solid fuel (unfermented lignin and cellulose residues), concentrate of nonferrous metals (copper, chromium, etc.) and clean water; 4). ability to scale and replicate typical technologies of designated purpose. Obtained engineering and technological parameters of universal biotechnologies indicate the prospects of their large-scale industrial implementation.

Dark fermentation of multicomponent solid food waste by soil hydrogen-producing bacterial community was studied in horizontal batch reactor under different mechanical mixing modes; speed of mixing (rpm) and frequency of mixing (duration mixing and pause) were selected as target for optimization. Addition of pH indicator bromothymol blue to the culture liquid allowed to study patterns of formation of acidification zones in solid/liquid/gaseous fermentation system. It was detected that mixing speed can contribute to sustainable maintenance of optimal pH values and prevent formation of spatial pH gradient. Adjusting of mixing and pause duration resulted in significant decrease of digestion cycle and increase in volumetric hydrogen production rate. Established optimal mixing mode 24 rpm, 10 min of mixing/20 min of pause provided biohydrogen yield 123 LH2 kg-1 TSadded and reduction in the concentration of total suspended solids from 70 to 0.75 g/L in 4 days.