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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.

The weed

Hydrogen production by microorganisms is studied by using different sources of carbon for their cultivation. Purple non-sulfur bacteria are capable of producing molecular hydrogen phototrophically with the simultaneous accumulation of biomass on organic substrates that may be waste from various industries. That fact makes the study of this group of microorganisms very much promising. The aim. The determination of the ability of purple non-sulfur bacteria Rhodopseudomonas yavorovii IMV B-7620 to produce hydrogen consuming different organic substrates and their effects on the main metabolic indicators of culture growth. Methods. Bacteria were grown in 100 mL glass jars in liquid modified ATCC No. 1449 medium for 14 days at temperature +27...+30ºC and at constant light (200 lux). Biomass accumulation and hydrogen production in the cultivation medium were determined using sodium acetate (12 and 36 mM), malate (12 and 36 mM), succinate (36 mM), glucose (36 mM), starch (36 mM), sodium citrate (36, 60, 90 mM). Biomass was determined turbidimetrically, the composition of the gas phase was determined using a gas chromatograph LHM-8-MD, redox potential and pH were estimated potentiometrically. The volume of gas synthesized was measured on a syringe scale. Determination of the content of organic acids in the culture liquid was analyzed by high performance liquid chromatography. Results. The utilization of organic compounds (malate, glucose, starch, sodium citrate) by R. yavorovii IMV B-7620 is accompanied by hydrogen synthesis. Under the growth with sodium acetate, bacteria produce small amounts of succinate. The malate metabolism results in the production of small amounts of fumarate on the 7th day of cultivation and isocitrate on the 10th day of cultivation. On the 14th day of cultivation, the cultural liquid contains a small amount of succinate. On the 14th day of cultivation, R. yavorovii IMV B-7620 produces 7.64±0.04% of hydrogen in the medium with malate (36 mM). However, the maximum concentration of hydrogen in the gas phase (21.26±0.08%) was gained on the 14th day of cultivation in the medium with sodium citrate. The maximum concentration of H2 in the gas phase during the growth in the medium with sodium citrate (60 mM) and NH4+ was 27.83±5.46% on the 7th day of cultivation and 35.69±0.40% with increasing concentration of sodium citrate up to 90 mM on the 10th day of cultivation. The total volume of hydrogen was 25.54±0.49 mL of H2 during the growth of R. yavorovii IMV B-7620 in the medium with 90 mM sodium citrate and NH4+. That is 1.5 times more than the amount of H2 produced during the growth of bacteria in the medium with 60 mM sodium citrate with the addition of NH4+. Conclusion. Purple non-sulfur bacteria R. yavorovii IMV B-7620 synthesize hydrogen during photofermentation of organic compounds. Bacteria were isolated from the water of Yavoriv Lake (Lviv region, Ukraine) formed as a result of flooding of the sulfur quarry. Bacteria consume sodium citrate, malate, glucose, starch and emit hydrogen. The total volume of hydrogen during the growth of R. yavorovii IMV B-7620 in the medium with 90 mM sodium citrate and NH4+ is 25.54±0.49 mL H2.

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.

UV irradiation is known to cause harmful effects on microorganisms. As the result, microorganisms have developed protection against exposure to harmful UV irradiation. We suggested that resistance to UV might be specific characteristic of certain genera of microorganisms. So, the aim of the work is to assess whether there is a correlation between UV resistance and the taxonomic position of microorganisms or is it the adaptation of cells to extreme conditions. There were studied 67 strains from extreme ecosystems (phytocenoses and оrnithogenic soil of the Antarctic, hypersaline ecosystems of the Crimea and the Dead Sea, the lake Baikal). Sequence of 16S rRNA genes, phylogenetic analysis and UV resistance were performed according to standard procedures. Phylogenetic analysis revealed live representatives of the following genera: Pseudomonas, Serratia, Rheinheimera, Aeromonas, Buttiauxella, Brevundimonas, Sphingomonas, Sphingopyxis, Dermacoccus, Frondihabitans, Microbacterium, Rhodococcus, Janthinobacterium, Arthrobacter, Micrococcus, Kocuria, Sphingobacterium, Flavobacterium, Chryseobacterium, Bacillus, Staphylococcus, Paenibacillus, Sporosarcina. Gram-positive bacteria were significantly more resistant to UV irradiation (LD99.99 750–1400 J/m2). Gram-negative had lower resistance (LD99.99 35–150 J/m2). Most pigmented strains were more resistant to UV than non-pigmented ones. According to the values of lethal doses of UV irradiation we suggest that investigated microorganisms have effective mechanisms to repair DNA damages. Resistance of microorganisms to UV, as a rule, was not related to the ecological features of their habitat. Thus, there is a correlation between the resistance of microorganisms to UV irradiation and their taxonomic position, which allows to consider UV resistance as a diagnostic feature at the genus level.

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.

Background: Multicomponent organic waste is a significant environment hazard. Natural mechanisms can no longer ensure the processing of increasing volumes of such waste. The accumulation of multicomponent organic waste to environment pollution with toxic gases and leachate. Therefore, there is an urgent need to develop cost-effective technologies for the rapid treatment of huge volumes of toxic waste. Moreover, multicomponent organic waste can be used as the substrate for the production of green energy - biohydrogen. Objective: To scale up the technology of biohydrogen production from multicomponent organic waste in experimental-industrial anaerobic batch reactor and to establish fermentation parameters of its operation. Methods: An experimental-industrial anaerobic batch reactor was designed and the method of thermodynamic prognosis was applied to determine the most effective microbial pathway for hydrogen synthesis. The efficiency of the fermentation was evaluated by the pH and redox potential (Eh, mV) of culture medium, the concentration and volume of synthesized gas. Results: The experimental-industrial anaerobic batch reactor with a volume of 240 L was successfully applied to scale up the process of obtaining hydrogen via fermentation of organics. The duration of the technological cycle (T) was 1.5-4 days. The coefficient of waste destruction (Kd) that is the ratio between the initial and final weight of waste was high and ranged from 86 to 140. Hydrogen yield was 45-90 L/kg of dry weight of waste. The maximum concentration of hydrogen (H2max) was 50-58%. Conclusion: The developed approach and scaling of the biotechnology is promising for industrial application for effective hydrogen production via dark fermentation of multicomponent organic waste. Its industrial application might help to solve the problem of toxic multicomponent organic waste destruction and simultaneously to produce green energy H2.

Increasing pollution of environment by toxic metals is the urgent problem requiring effective solution worldwide. The goal of the work was to study the dynamics of the interaction of Cr(VI), Mo(VI), W(VI) compounds with obligate anaerobic microorganisms Clostridium butyricum GMP1, which ferment organic compounds with the synthesis of hydrogen. The standard methods were used to determine рН and redox potential (Eh), the gas composition, and the concentration of metals. The application Clostridium butyricum GMP1 was showed to be useful to investigate its interaction with toxic metals. The higher redox potential of metal provided the opportunity for its faster and more effective reduction. The patterns of the reduction of toxic metals Cr(VI), Mo(VI) and W(VI) by obligate anaerobic strain Clostridium butyricum GMP1 were obtained. The experimental data confirmed the thermodynamically calculated correlation between the redox potential of the metal reduction to insoluble form and effectiveness of its removal. Obtained results can serve as the basis for further optimization and development of environmental biotechnologies for wastewater treatment with the simultaneous destruction of solid organic waste and hydrogen synthesis.

Chromium(VI) is one of the most hazardous contaminant of the water and soil environment. Thermodynamic calculations enable to determine the optimal metabolic pathways for microbial extraction of toxic soluble hexavalent chromium compounds from contaminated sewage. The purpose of this research was to predict theoretically and confirm experimentally the possibility of hazardous chromium(VI) removal by hydrogen producing microbiome with simultaneous destruction of multicomponent organic waste and hydrogen synthesis. Gas composition was determined by the standard gas chromatography method. The redox potential (Eh) and рН of the medium were measured potentiometrically by EZODO MP-103 universal ionomer. The Cr(VI) concentration was determined by a photocolorimetric method with 1,5-diphenylcarbazide (DFK). Multicomponent organic waste was effectively destroyed by hydrogen producing microbiome in control conditions (at the absence of chromium). Maximum concentration of H2 was 36% and biohydrogen yield was 81 l/kg of absolutely dry weight of waste. The weight of organic waste was 92 times decreased (Kd=92) during only 82 hours. The hydrogen fermentation cycle was not significantly inhibited by addition of Cr(VI). Thus, the efficiency of waste destruction and biohydrogen yield decreased consequently on 10% (Kd=83) and 7% (75 l/kg of waste) after addition of 50 ppm Cr(VI) to the culture liquid at the beginning of the final phase (50 hours) of the fermentation. As it was expected, the addition of 100 ppm Cr(VI) into the liquid phase during the final fermentation phase (80 hours) caused rapid increase of the redox potential and short-term inhibition of the fermentation process. However, after complete reduction of soluble CrO42- to insoluble Cr(OH)3∙nH2O↓ by hydrogen producing microorganisms, H2 synthesis resumed and metabolic parameters returned to initial values (the Eh was -185 mV and -99 mV after complete extraction of 50 ppm and 100 ppm Cr(VI) consequently). The optimal pathway of microbial detoxification of toxic chromium(VI) compounds was thermodynamically predicted and experimentally confirmed. High efficiency of CrO42- removal by strict anaerobic hydrogen producing microbiome via dark hydrogen fermentation of multicomponent organic waste was demonstrated. The obtained results could be used as the basis for development of novel environmental biotechnology of chromium-containing sewage purification and simultaneous destruction of environmentally hazardous organic waste as well as obtaining of eco-friendly energy carrier – biohydrogen.

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.

Plants of the Ambrosia genus are invasive and cause many ecological problems, including the oppression of the growth of agricultural crops and native plants, land depletion, and the production of strong allergens. The use of weeds as a sustainable feedstock for biogas production, either methane or hydrogen, is a promising way to fulfill the energy needs of the current generation, eliminate the depletion of non-renewable carbon resources, and preserve the ecosystem degradation caused by invasive species impacts. A diversified microbial community was used as inoculum and Ambrosia artemisiifolia L. biomass as a substrate for anaerobic degradation and methane production. In this regard, the development of biotechnological approaches to ragweed degradation will promote the integration of new renewable energy systems. Herein, we have shown the high effectiveness of combining the processes of anaerobic degradation of plant biomass for methane production and detoxification of meal-containing model sewage by a diversified microbial community. Thus, the maximum methane yield was 56.0 L kg−1 TS. The presence of 500 mg L−1 Cu(II) slightly inhibited methane synthesis, and the methane yield was 38.4 L kg−1 TS. In contrast to a diversified microbial community, the natural microbiome of ragweed almost did not synthesize methane and did not degrade plant biomass (Kd = 2.3). Methanogens effectively immobilized Cr(IV), Cu(II), and Fe(III) during ragweed fermentation at initial concentrations of 100–200 mg L−1. The obtained results showed the high effectiveness of applying a diversified microbial community in a sewage treatment plant for the degradation of a noxious plant, Ambrosia artemisiifolia L.

The accumulation of various types of waste containing both organic and inorganic metal-containing compounds is extremely hazardous for living organisms. The possibility of polymer degradation, biohydrogen synthesis, and metal detoxification via the dark fermentation of model potato waste was investigated. For this purpose, the strict anaerobic strain was isolated and identified as Clostridium butyricum. The high efficiency of dark hydrogen fermentation of potatoes with yield of hydrogen in 85.8 ± 15.3 L kg−1 VSpotato was observed. The copperand chromium salts solutions were added to the culture fluid to obtain the concentrations of 50, 100, and 200 mg L−1 Cu(II) and Cr(VI) in the active phase of growth (19 h of cultivation). Metals at a concentration of 200 mg L−1 inhibited the fermentation process the most. The hydrogen yield decreased in 7.2 and 3.6 times to 11.9 ± 2.1 and 23.8 ± 5.6 L kg−1 VSpotato in the presence of 200 mg L−1 Cu(II) and Cr(VI), respectively. The efficiencies of the chromium bioremoval in all variants of the experiment were 100%, and those of copper bioremoval were about 90%. A pure culture of strict anaerobes Clostridium butyricum strain 92 was used for the first time for the detoxification of metals. The presented results confirmed the possibility of this promising strain application for industrial H2 production and the bioremediation of contaminated sites.

This study presents high-quality draft genome assemblies of six bacterial strains isolated from the roots of wheat grown in soil contaminated with cadmium. The results of this study will help to elucidate at the molecular level how heavy metals affect interactions between beneficial rhizobacteria and crop plants.

This study evaluates the effect of lignocellulosic substrate obtained after hydrogen dark fermentation of food waste on plant growth using the radish Raphanus sativus L as an example. Addi...

Aim. The research was focused on the assessment of the possible resistance of Antarctic microorganisms to mercury ions. Methods. Conventional microbiological methods of introducing of decimal dilutions to agar medium. Results. Microorganisms resistant to Hg2+ in high concentrations (up to 500 mg/l) were discovered among samples from Antarctica. The majority of Hg2+-resistant microorganisms was found in moss-lichen and soil ecosystems. The least of Hg2+-resistant microorganisms was found in organics-rich humus ecosystems. Conclusions. In Antarctic microbiocenoses were discovered for the first time microorganisms resistant to mercury in “bactericidal” concentrations in spite of absence of this element in the natural ecosystems. Apparently, the genome of these microorganisms contains genes that provide the mechanisms of microbial resistance to toxic mercury. Keywords: mercury, metal resistance, Antarctic microorganisms.

Aim. Determination of taxonomic position and resistance to Cd2+, Cu2+, Ni2+, Co2+, CrO42- of isolated bacteria from cadmium-contaminated soils. Methods. Bacterial cultures were isolated by ten-fold dilutions and further cultivation on agarized nutrient medium. Taxonomic position of isolated cultures was determined by molecular-genetic methods using GenBank and BLAST. Bacterial resistance to toxic metals was determined by strains cultivation in liquid medium in the presence of concentration gradient of Cd2+, Cu2+, Ni2+, Co2+, CrO42-. Results. Isolated cultures were highly resistance to cadmium. These bacterial cultures were identified as Brevundimonas vesicularis and Cupriavidus gilardii by phenotypic and molecular-genetic characteristics. Their resistance was in one order higher comparing to generally accepted. Conclusions. Isolated strains are promising for using in novel industrial biotechnologies for metal containing wastewater treatment. Keywords: metalresistance, toxic metals, taxonomic position, Cupriavidus gilardii, Brevundimonas vesicularis.

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.

The aim of the work was to optimize the ratio of weight of solid (food waste) and liquid (water) phases in order to ensure high efficiency of molecular hydrogen synthesis and degradation of multi-component food waste. Assessment of the efficiency of fermentation process was carried out using colorimetric and potentiometric methods for pH and redox potential measuring, volumetric and chromatographic methods for volume and composition of gas investigation, and mathematical calculations for fermentation parameters determination. The dynamics of hydrogen fermentation of waste in the horizontal reactor using different ratios of solid (food waste) and liquid (water) phases was investigated. The optimization of the ratio of solid and liquid phases was shown to lead to the increase in efficiency of molecular hydrogen synthesis and destruction of waste particles. The ratio of solid and liquid phases 1:3 was determined to be optimal for the effective synthesis of hydrogen as well as for maximum waste decomposition. It provided effective hydrogen fermentation of multi-component food waste and allowed to rationally use material and technical resources. Obtained results are promising for further development of efficient industrial biotechnologies for waste destruction with the simultaneous synthesis of environmentally friendly energy carrier, i.e. molecular hydrogen.

Solid food waste is a significant threat to the environment. Thermodynamic calculations allow determining theoretically possible metabolic pathways for degradation of organic compounds by microorganisms, and also to select the optimal one to increase efficiency of food waste recycling. The purpose of our work was application of thermodynamic calculations to find out suitable fermentation parameters for regulation of microbial metabolism to ensure high rate of waste decomposition and formation of valuable products. The following methods were used: for pH and oxidation-reduction potential (ORP) measuring – colorimetric and potentiometric, for volume and composition of synthesized gas study – volumetric and chromatographic, for fermentation parameters calculation – mathematical. Fermentation of multicomponent kitchen food waste under theoretically calculated optimal parameters pH = 7.0 and Eh = –250...–350 mV provided extremely high metabolic activity of hydrogen-producing microbial community which resulted in decrease in duration of batch fermentation from to 3 days, increase in hydrogen yield from 16 to 80-115 L/kg of dry waste. The coefficient of waste destruction (Kd) that is ratio of initial and final weight of waste reached 91. Obtained after fermentation unfermented lignocellulosic substrate was shown to be applied as plant probiotics and supply mineral nitrogen for plant nutrition in arid condition. Thus, high efficiency of application of thermodynamic prognosis method of microbial interaction with organic compounds was shown to become the base for biotechnology of destruction of environmentally hazardous solid food waste with simultaneous obtaining of valuable products: environmentally friendly energy carrier – molecular hydrogen, as well as lignocellulosic substrate to increase crop yields. DOI: http://dx.doi.org/10.5755/j01.erem.74.4.20723

Nitrochloroaromatic compounds (NCAC) are one of the most toxic for humans and caused different disorders getting into food chain through agricultural soils with wastewater from enterprises of organic synthesis. It was shown a successful way of destruction of such compounds by microorganisms. The aim of our study was to check the resistance and the ability to degrade NCAC of 17 wheat rhizosphere bacterial strains. It was shown that rhizospheric strains were highly resistant to 1-nitro-4-chlorobenzene (NCB) – the representative compound which combines negative effects of nitro- group, chlorine and aromatic ring. The level of resistance was up to 300 mg/L of NCB. Studied strains were able to degrade it to the end products (CO2, H2O). Moreover, 10 between 17 bacterial strains were able to use 1-nitro-4-chlorobenzene as an additional source of Carbon and energy. These promising results could be used in rhizoremediation biotechnologies.DOI: http://dx.doi.org/10.5755/j01.erem.74.3.21069

Multi-resistant to extreme factors spore-forming bacteria of Bacillus genus are isolated from hypersaline environments of the Crimea (Ukraine) and the Dead Sea (Israel). Phylogenetic analysis showed distinction of dominating extremophilic culturable species in studied regions. In Crimean environments they are B. mojavensis and B. simplex, in the Dead Sea ecosystem--B. subtilis subsp. spizizenii, B. subtilis subsp. subtilis, B. licheniformis and B. simplex. Isolates are simultaneously halotolerant and resistant to UV radiation. Strains isolated from the Dead Sea and the Crimea environments were resistant to UV: LD90 and LD99.99 made 100-170 J/m2 and 750-1500 J/m2 respectively. Spores showed higher UV-resistance (LD99.99-2500 J/m2) than the vegetative cells. However the number of spores made 0.02-0.007% of the whole cell population, and should not significantly affect the UV LD99.99 value. Isolates of both environments were halotolerant in the range of 0.1-10% NaCl and thermotolerant in the range of 20-50 °C, and didn't grow at 15 °C. Survival strategy of spore-forming bacteria from hypersaline environments under high UV radiation level can be performed by spore formation which minimize cell damage as well as efficient DNA-repair systems that remove damages.

In this paper it was given the effect of p-nitrochlorobenzene (NCB) on the homeostasis quantitative parameters of cave clays microbial communities from Western Ukraine and Abkhazia (Mushkarova Yama, Kuybushevskaya) and soils of Ecuador tropical ecosystems. For these microbial communities were determined maximum permissible concentrations and types of responses on xenobiotic. Microbial communities of Mushkarova Yama cave clays and rainforest soils of Ecuador were characterized by the first type of response. Microbial communities of Kuybushevskaya clays and mountain jungles of Ecuador were characterized by the second type of response. Maximum permissible concentration of NCB for Mushkarova Yama was 200 mg/l, for the other studied microbial communities--300 mg/l. It was shown, that microbial communities were not only highly resistant to NCB but also interacted with it by destroying this xenobiotic and decreasing its concentration in 4 times.

Microbial communities of the Ecuadorian Andes and volcano Tungurahua were shown to be super resistant to representative toxic metals. Maximum permissible concentrations of toxic metals were 100 ppm of Hg2+, 500 ppm of Co2+ and Ni2+, 1000 and 1500 ppm of Cr(VI), 10000 and 20000 ppm of Cu2+. The effect of metal concentration increasing on the biomass growth, CO2 and H2 synthesis was investigated. Two types of response of microbial communities on the increasing of toxic metals concentrations were discovered. The first type of response is the catastrophic inhibition of microbial growth. The second type of response is the absence of microbial growth inhibition at certain metal concentration gradient. The succession of qualitative structure of Ecuadorian microbial communities was shown for the first time. Bacteria, yeasts and finally fungi consistently dominate in the microbial community at the Cu2+ concentration raising. Microorganisms resistant to ultra-high concentrations of toxic metals (e.g., 3000 ... 20000 ppm of Cu2+) were isolated from Ecuadorian ecosystems. These microorganisms are able to accumulate toxic metals.

Целью работы был количественный учет железовосстанавливающих бактерий в природных экосистемах Антарктики, Арктики, Мертвого и Черного морей, средних широт (Украина, Абхазия) и экваториальной зоны (Эквадор). Использованы метод количественного учета микроорганизмов по Мак-Креди, колориметрический метод определения соединений Fe(II) в культуральной жидкости. Впервые проведено системное исследование численности железовосстанавливающих бактерий обоих полушарий в экосистемах шести географических областей. Экспериментально показана высокая численность железовосстанавливающих бактерий в природных экосистемах. Их количество составило от 1,1·102 до 2,8·107 кл/г абсолютно сухого образца. Представленные результаты свидетельствуют о том, что железовосстанавливающие бактерии являются неотъемлемой составляющей природных экосистем и могут существенно влиять на биогеохимические циклы трансформации соединений железа и углерода., The aim of the work was quantitative determination of Fe(III)-reducing bacteria in natural ecosystems of the Antarctic, the Arctic, the Dead and the Black Sea, middle latitude (Ukraine, Abkhazia) and the equatorial zone (Ecuador). It was used the method of quantitative determination of microorganisms by McCready and the colorimetric method for determination of Fe(II) compounds . Results. The systemic study of the number of Fe(III)-reducing bacteria of both hemispheres in the ecosystems of six geographic regions was carried out for the first time. High number of Fe(III)-reducing bacteria in natural ecosystems was experimentally shown. The number of Fe(III)-reducing bacteria ranged from 1.1•102 to 2.8•107 cells/g of absolutely dry sample. Conclusions. The presented data showed that Fe(III)-reducing bacteria are an integral part of natural ecosystems and can significantly affect the biogeochemical cycles of iron and carbon compounds transformation.

The focus of the study was interaction of Candida tropicalis RomCu5 isolated from highland Ecuador ecosystem with soluble and insoluble copper compounds. Strain C. tropicalis RomCu5 was cultured in a liquid medium of Hiss in the presence of soluble (copper citrate and CuCl2) and insoluble (CuO and CuCO3) copper compounds. The biomass growth was determined by change in optical density of culture liquid, composition of the gas phase was measured on gas chromatograph, redox potential and pH of the culture fluid was defined potentiometrically. The concentration of soluble copper compounds was determined colorimetrically. Maximal permissible concentration of Cu2+ for C. tropicalis RomCu5 was 30 000 ppm of Cu2+ in form of copper citrate and 500 ppm of Cu2+ in form of CuCl2. C. tropicalis was metabolically active at super high concentrations of Cu2+, despite the inhibitory effect of Cu2+. C. tropicalis immobilized Cu2+ in the form of copper citrate and CuCl2 by it accumulation in the biomass. Due to medium acidification C. tropicalis dissolved CuO and CuCO3. High resistance of C. tropicalis to Cu2+ and ability to interact with soluble and insoluble copper compounds makes it biotechnologically perspective.

The aim of the study was regulation of metabolism of Citrobacter freundii Ml-31.1/1 on the basis of thermodynamic calculations. The essence of metabolism regulation was in ability to perform two opposite processes, namely mobilization and immobilization of iron compounds, depending on the culture conditions by single strain C. freundii Ml-31.1/1. The following methods were used: potentiometric measuring of pH and Eh values, colorimetric determination of microbial biomass increase and changes of iron compounds concentration, gas chromatography. The possibility of theoretically grounded regulation of iron transformation pathways was experimentally confirmed. Single culture (C. freundii Ml-31.1/1) provided both immobilization and mobilization of iron compounds due to specific conditions for microbial growth in nutrient medium.. Obtained regularities are the basis for assessing the role of microorganisms in iron biogeochemical cycles. This data could be used as a basis of effective biotechnologies of iron extraction from depleted deposits and water purification from iron compounds.

Antarctic plants are stable specific microenvironments for microbial colonization that are still less explored. In this study, we investigated cultivable heterotrophic bacteria and yeasts dominating in plant samples collected from different terrestrial biotopes near Ukrainian Antarctic Base on Galindez Island, maritime Antarctica. Phylogenetic analysis revealed affiliation of the bacterial isolates to genera Pseudomonas, Stenotrophomonas, Brevundimonas, Sporosarcina, Dermacoccus, Microbacterium, Rothia and Frondihabitans, and the yeast isolates to genera Rhodosporidium, Cryptococcus, Leucosporidiella, Candida and Exophiala. Some ecophysiological properties of isolated strains were determined that are important in response to different stresses such as psychro- and halotolerance, UV-resistance and production of hydrolytic enzymes. The majority of isolates (88 %) was found to be psychrotolerant; all are halotolerant. Significant differences in survival subsequent to UV-C radiation were observed among the isolates, as measured by culturable counts. For the bacterial isolates, lethal doses in the range 80-600 J m⁻² were determined, and for the yeast isolates--in the range 300-1,000 J m⁻². Dermacoccus profundi U9 and Candida davisiana U6 were found as most UV resistant among the bacterial and yeast isolates, respectively. Producers of caseinase, gelatinase, β-glucosidase, and cellulase were detected. To the best of our knowledge, this is the first report on isolation of UV resistant strain D. profundi, and Frondihabitans strain from Antarctica, and on detection of cellulase activity in Antarctic yeast strain C. davisiana. The results obtained contribute to clarifying adaptation strategies of Antarctic microbiota and its possible role in functional stability of Antarctic biocenoses. Stress tolerant strains were detected that are valuable for ecological and applied studies.