Standard Nutrient Medium Research Articles

Administration of Essential Phospholipids Prevents Drosophila Melanogaster Oocytes from Responding to Change in Gravity.

The aim of this study was to prevent initial changes in Drosophila melanogaster oocytes under simulated weightlessness and hypergravity at the 2 g level. Phospholipids with polyunsaturated fatty acids in the tail groups (essential phospholipids) at a concentration of 500 mg/kg of nutrient medium were used as a protective agent. Cell stiffness was determined using atomic force microscopy, the change in the oocytes' area was assessed as a mark of deformation, and the contents of cholesterol and neutral lipids were determined using fluorescence microscopy. The results indicate that the administration of essential phospholipids leads to a decrease in the cholesterol content in the oocytes' membranes by 13% (p < 0.05). The stiffness of oocytes from flies that received essential phospholipids was 14% higher (p < 0.05) and did not change during 6 h of simulated weightlessness or hypergravity, and neither did the area, which indicates their resistance to deformation. Moreover, the exposure to simulated weightlessness and hypergravity of oocytes from flies that received a standard nutrient medium led to a more intense loss of cholesterol from cell membranes after 30 min by 13% and 18% (p < 0.05), respectively, compared to the control, but essential phospholipids prevented this effect.

МИКРОВОДОРОСЛИ ХЛОРЕЛЛА ДЛЯ ОЧИСТКИ СТОКОВ В СЕЛЬСКОМ ХОЗЯЙСТВЕ

A promising way to solve current problems of energy saving and reducing environmental pollution may be the use of microalgae. These simple microorganisms are capable of purifying contaminated wastewater in agriculture. Wastewater contains nitrogen, phosphorus, sulfate and other contaminants. In order to optimize the technology of obtaining biodiesel fuel from lipid components in the conditions of small agricultural producers, the possibility of using Chlorella vulgaris in cleaning from ammonium ions and phosphate ions was studied. Chlorella was cultivated in a photobioreactor on a standard Tamiya medium and wastewater for 10 days at a temperature of 30 ° C and an illumination of 14 kLx in the red (620-740 nm), blue (430-500 nm) and green (500-565 nm) wavelength ranges. The filtrate of the microalgae suspension was collected over several days and assessed for the content of phosphate and nitrate ions using a photometric method. The greatest increase was observed with illumination in the red range (2 times higher), the minimum value in the green. The studies found that cell growth occurs both in synthetic, standard nutrient media and in wastewater, the latter being more costeffective. It was found that when adding chlorella to wastewater, the maximum decrease in the content of ammonium ions and phosphate anions is observed on the 6-7th day (by 19-59% and 5-29%, respectively), which is most likely due to the use of these elements by microalgae for nutrition and maintenance of life. A scheme for growing Chlorella vulgaris on wastewater for further production of lipid components of biodiesel fuel is proposed.

ИЗУЧЕНИЕ БИОЛОГИЧЕСКОЙ ПОЛНОЦЕННОСТИ СПЕРМАТОЗОИДОВ В СПЕРМЕ С БАКТЕРИАЛЬНОЙ ОБСЕМЕНЕННОСТЬЮ

The aim of the study is to investigate the relationship between bacterial contamination of bull semen and the biological value of spermatozoa, as well as reproductive performance. The object of the study was Holstein bulls (n = 17). The material for the study was frozen-thawed semen of bulls in the amount of 61 samples. Microbiological studies of sperm doses were carried out using standard nutrient media in accordance with GOST 32222-2013. The total number of microorganisms was calculated by the number of grown colony-forming units (CFU/ml) in 1 cm3, with subsequent determination of their morphological pro-perties. Sperm motility and morphology were determined using the Argus CASA program. The state of DNA in spermatozoa was studied by the acridine orange test (AO test) using a fluorescence microscope. The study revealed a high positive correlation (r = +0.940**) between the number of microorganisms in sperm and pathology in individual sperm segments. Analysis of variance confirmed a statistically significant effect of the number of microorganisms on sperm morphology F = 123.2 (p=0.000). The correlation relationship between the fragmentation index and the content of microorganisms has a high value (r = +0.965**). Sperm motility negatively correlates (r = –0.768**) with the number of microorganisms (CFU/ml). In the presence of Mycoplasma spp in the samples, the number of cows with fruitful insemination was 35.5 % due to reduced motility, morphology and high fragmentation of sperm DNA (58 %). Sperm motility in samples containing Mycoplasma spp averages 24.5 %, while in samples without these microorganisms it is 48.9 %. Thus, it can be assumed that the presence of Mycoplasma spp in samples and high bacterial contamination rates lead to to lower reproductive performance in bulls.

Bakteryjna redukcja siarczanów jako odpowiednia metoda usuwania siarczanów z kwaśnych wód kopalnianych

The aim of this work was to investigate of the sulfates removal from acid mine drainage (AMD) by biological method using sulfate-reducing bacteria (SRB). A sample of AMD out-flowing from the Pech shaft of the abandoned and flooded Smolník deposit in Slovak Republic was studied. The untreated AMD (with contents metals) and treated AMD i.e. after of the metals removing by the synthetic sorbent Slovakite were used. The base of the biological sulfates elimination was the sulfates bacterial reduction under influence of SRB genera Desulfovibrio. These bacteria realize the sulfates reduction to hydrogen sulfide at the simultaneously oxidation of energetic substrate. Standard selective nutrient medium DSM-63 and modified selective nutrient medium DSM-63 (without sulfates contents) with standard amount of sodium lactate (as energetic substrate) were used in the experiments with untreated AMD. Standard selective nutrient medium DSM-63 and modified selective nutrient medium DSM-63 with standard, double and triple amount of sodium lactate were used in the experiments with treated AMD. In the case of untreated AMD has been reached low removing of sulfates - 20% efficiency (standard medium) and 26% (modified medium). The formation of heterogeneous precipitates containing metals pointed to the need for treatment of AMD by the initial removal of metals by sorption on Slovakite sorbent and subsequent removal of sulfates by bacterial reduction. The results of experiments with AMD treated in this way showed 49%, 70% and 88% efficiency of sulfate removal when using sodium lactate in standard, double and triple amounts. The results of this work suggest that ratio of substrate quantity and sulfate concentration is one of the key parameter of sulfate reducing condition. However, the price of the energy substrate is also an important factor. Therefore, subsequent experiments will be focused on the use of the more affordable substrates (e.g. whey) or mixed bacterial culture of SRB, which will also be able to use the products of decomposition of basic energetic substrates.

LEVELS OF CARBOHYDRATES IN SHORT-LIVED STRAIN OF Drosophila melanogaster

Aim. The aim of this study was to investigate the concentrations of key energetic substrates such as glucose, fructose, and trehalose, in control and artificially selected flies shown to have shorter lifespan. Methods. For all experiments flies were maintained on standard yeast-sucrose nutrient medium consisted of 5% sucrose, 5% yeast, 1% agar and 0.18% nipagin as mold growth inhibitor. Experimental line of flies was selected on high-protein diet and previously showed short lifespan. Newly enclosed flies were kept two days for mating and used for measurement of feeding behavior and fecundity. Some flies were frozen at -80 °C for further analysis. Concentrations of glucose, fructose and trehalose were measured by Gas Chromatography/Mass Spectrometry using described protocol and expressed per wet weight. Results. Amount of glucose was significantly higher in experimental flies of both sexes. Male flies had about 70% more free glucose and females for about 45%. These differences were accompanied with higher amounts of trehalose that consist of two molecules of glucose and is a form of glucose storage in Drosophila. Trehalose content in experimental males was 2-fold higher, while in females it was higher for about 1.8-fold. Fructose content was also higher in experimental flies. This carbohydrate is metabolized through glycolysis, providing energy in the form of ATP. Beyond energy production, fructose plays a role in supporting reproductive processes such as oogenesis in females, though measure of fecundity showed no difference. Conclusions. Our results show that despite similar consumption of food and reproduction offspring of artificially selected flies have shorter lifespan. However, this effect can be explained by lower energetic status while flies store more energetic substrates such as glucose, fructose and trehalose.

Changes in the Vital Signs of Drosophila Oil-Resistant Lines, Depending on the Conditions of Detention

The paper analyzes the effect of oil on the survival and fertility of Drosophila melanogaster lines that differ in oil resistance. A study was made of wing morphoses in female flies of oil-resistant lines and flies, oil-resistant lines in a pure nutrient medium. In studies conducted at the Department of Ecology and Genetics, an oil-resistant line of fruit flies was bred, capable of not only surviving, but also reproducing in conditions of high oil concentration: half of the semi-lethal (2.5%) and semi-lethal (5%). The main indicators of the vital activity of flies reached the level of control (do not differ from the standard) by the 60th - 70th generation of keeping in conditions of oil pollution. Currently, flies kept, living and breeding in an oil-polluted environment have gone through more than 600 generations of development. Options used in the experiment: control contained on a standard nutrient medium; flies adapted to semi-lethal (5%) concentration of oil in the environment; flies adapted to half of the semi-lethal (2.5%) concentration of oil in the environment; flies adapted to 5% concentration, but transplanted to a pure nutrient medium (non-adaptive conditions); flies adapted to 2.5% concentration, but transplanted to a pure nutrient medium (non-adaptive conditions). Of interest was the opportunity to analyze the main indicators of vital activity and the presence of wing morphoses of fruit flies of an oil-resistant line, under conditions of oil pollution and when transferred to a clean nutrient medium (maladaptive conditions).

Influence of chitosan-stabilized silver nanoparticles on the physiological and biochemical state of potato plants (&lt;i&gt;Solanum tuberosum&lt;/i&gt; L.) &lt;i&gt;in vitro&lt;/i&gt; culture

The article contains the results of study of the influence of added to culture medium silver-containing chitosan- based nanocomposites (Chitosan-Ag) at a dilution of 1:500 and 1:1000 (the mass ratio of the components is 50:1 for Chit- Ag 50:1 and 100:1 for Chit-Ag 100:1) on the development of potato microshoots and microclones with a formed root system. Potato microshoots cultivated for 4 weeks on nutrient medium modified with nanocomposites were characterized by slow development and the absence of rhizogenesis, which indicates the toxic effect of the studied nanocomposite concentrations. When replacing the standard nutrient medium with nanocomposites modified for a potato microclone with developed roots, the Chit-Ag 50:1 reduced the rate of growth and development of microclones compared to control and pure chitosan. The Chit- Ag 100:1 nanocomposite had no influence on the microclone growth compared to the control, but reduced the root biomass compared to chitosan. The preservation of photosynthetic pigments and proline concentrations with decreasing the hydrogen peroxide level indicates the absence of the toxic effect of silver-containing chitosan-based nanocomposites on the formed potato microclones. The chitosan concentration increase in the nanocomposite composition helps us to reduce the toxic effect due to the formation of a dense stabilizing shell that delays the silver ion generation.

Study of the Oxolin antiviral drug effect for the improvement of potato seed material during in vitro cultivation

The article presents an analysis of the potato breeding problems in Russia which are associated with the low phytosanitary state of potato seed material infected with viral and bacterial diseases, as a result, it is necessary to carry out its improvement and the use of Russian varieties. Experiments were conducted in the laboratory of plant microclonal propagation according to the methodological recommendations for improvement and accelerated propagation of seed potatoes. The results of research on refining the technology of seed potato improvement by adding the Oxolin antiviral drug to the standard nutrient medium MS; its optimal concentrations for obtaining the largest number of uninfected plants of the studied varieties were identified. For potato varieties Liga, Hussar, and Real, the optimal concentration was 20 mg/l of Oxolin, while in the varieties Aurora, Real, and Sirenevy tuman, the concentration was 30 mg/l. Therefore, it is necessary to search for antiviral drugs with an alternative mechanism of action which remains very relevant and practically significant. The research results obtained in this work can be applied both to optimize the cultivation regime of potato microclones in vitro and to enhance the productive process of the uninfected microplants.

Biocompatibility of an interspinous implant made of titanium alloys

BACKGROUND: At present, metal implants are widely used in neuro-orthopedics, of which titanium alloys are of particular interest. A team of authors developed an original combined implant for posterior spinal fusion as an import substitution, which can be used from one-way access during minimally invasive operations on the lumbar spine. The implant was manufactured at the Endocarbon Enterprise in Penza. For better osseointegration, it is made of VT6 alloy and titanium nickelide. The middle part of the implant is laser-treated to create an uneven surface in the hope of better integration in the tissues of the body. This study was conducted to assess the cytotoxicity and biocompatibility of this implant for its further application in clinical practice.&#x0D; AIM: To determine the cytotoxicity of an interspinous implant made of titanium alloys for its further introduction into spinal surgery.&#x0D; MATERIALS AND METHODS: To determine the cytotoxicity of titanium samples of interspinous implants, a methyltetrazolium test was conducted to assess the viability of stromal cells in the presence of a nutrient medium after incubation with the test material. The biocompatibility of the material was analyzed using scanning electron microscopy of samples 1 and 7 days after cell culture.&#x0D; RESULTS: The viability of cells cultured in the presence of a nutrient medium after incubation with samples of titanium VT6 was 105% and that of titanium nickelide was 98%, which were comparable to the viability of cells in a standard nutrient medium. With electron microscopy, after 1 day of cultivation, cells form a monolayer on a titanium surface, all cells were well spread out and formed intercellular contacts, and after 7 days of cultivation, the number of cells increased and they formed a dense monolayer.&#x0D; CONCLUSIONS: The interspinous implant, which includes alloys of titanium VT6 and titanium nickelide, is biocompatible with cultured cells and can be introduced into spinal surgery.

Double Coordination Compounds of Fe(II)/Co(II)/Ni(II)/Cu(II) 1,10-Phenanthroline/2,2ʹ-Bipyridine Cations with Tartratogermanate(IV) Anions as Novel Nonresistant Antimicrobial Agents

Objective. To study the antimicrobial activity of double coordination compounds with 1,10-phenanthroline/2,2ʹ-bipyridine complexes of Fe(II)/Co(II)/Ni(II)/Cu(II) as cations and diff erent tartratogermanate(IV) anions, reveal the main factors of their effi ciency and establish relations between their composition, structure features, and biological properties. Methods. The developed synthesis method allowed us to obtain three diff erent tartratogermanate anions, which exist together in the solution and can be selectively recognized by the certain type of 1,10-phenanthroline/2,2ʹ-bipyridine cation. Th e antimicrobial activity of the compound was investigated by a rapid twofold dilution method in a standard liquid nutrient medium (Hottinger digestion) to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Results. Th e complex nature of studied compounds, synergism of their biologically active structural units, and the presence of diff erent types of intermolecular bonds result in the high antimicrobial activity against a wide range of microorganisms such as gram-positive Planococcus citreus, Microcoсcus luteus, Bacillus cereus, Staphylococcus aureus, Streptococcus lactis, and, in a less degree, gram-negative Escherichia coli and Agrobacterium tumefaciens. Compounds (1)—(8) show a high antimicrobial activity because all of them belong to the type of double coordination compounds and contain similar structural units. Nevertheless, complexes (1) (23.44 μg/mL), (3) (46.9 μg/mL), (4) (23.44 μg/mL), and (8) (46.9 μg/mL) turned out to be the most eff ective, while (6) (&gt;500 μg/mL) and (7) (&gt;500 μg/mL) are less productive. Complexes that have anions [Ge2(OH)(H2Tart)(μ-Tart)2]3- (1), (8) and [Ge2(OH)(HTart)(μ-Tart)2]4- (4) with free hydroxyl and carboxyl groups of the terminal tartaric acid are able to interact with metals in the enzymes of microorganisms and appear to be better antimicrobial drugs because they show lower inhibitory and bactericidal concentrations. Conclusions. Structural features such as the cation-anionic type of compounds, variability of intermolecular interactions, joint of diff erent biologically active units and free chelating groups in tartaric ligands lead to the combination of different action mechanisms and exclude the possibility of strain resistance.

Study of biocompatibility &lt;i&gt;in vitro&lt;/i&gt; of ultrafine-grained Zn-based bioresorbable alloys

Background. Zinc alloys have advantages for use as biodegradable implantable orthopedic metal structures due to the absence of gas formation in comparison with magnesium alloys. But their mechanical properties are often has lower values.Aim. Investigation of effect of high-pressure torsion (HPT) on strength, ductility, corrosion resistance, antimicrobial properties, surface cell colonization and biocompatibility of Zn-based alloys.Materials and methods. The alloys of the Zn-x%Mg system (where x = 0; 1 and 1.7 %) in the initial undeformed state and after HPT were investigated in this work. Mechanical properties were studied on an Instron 3382 testing machine at room temperature. The biocompatibility of the alloys was evaluated by hemolytic activity and cytotoxicity assesment. We also studied the stimulation of colonization of the surface of the samples by mesenchymal multipotent stromal cells, as well as the presence of antimicrobial properties relative to the Escherichia coli culture. To study the degradation rate, the alloy samples were incubated in a standard nutrient medium for 8 days, assessing the change in their mass relative to the initial value.Results. It has been established that HPT leads to an increase in the strength of pure Zn 2 times, and of Zn-1%Mg and Zn-1.7%Mg alloys by 3 and 5.5 times, respectively, with an increase in their ductility. At the same time, deformation treatment has practically no effect on the corrosion resistance of the initial materials. No significant increase in the hemolytic activity and bactericidal activity of the alloys was revealed during studies. However, a significant decrease in the ability of cells to colonize the surface of pure zinc was observed after HPT.Conclusion. HPT leads to a significant increase in the strength and ductility of studied materials. At the same time, a decrease in the biocompatibility of zinc-based alloys after HPT did not observed. It was found that the discovered cytotoxic effect was obviously caused not so much by the alloy processing method as by its chemical composition. This makes it possible to evaluate the studied alloys of the Zn-x%Mg system treated by HPT (and, in particular, the Zn-1.7%Mg alloy) as a promising structure for the development of biodegradable orthopedic products.

Study of the Polysaccharide Production by the Microalga Vischeria punctata in Relation to Cultivation Conditions.

Vischeria punctata is a unicellular microalga that has industrial potential, as it can produce substances with beneficial properties. Among them, endopolysaccharides (accumulated in cells) and exopolysaccharides (released by cells into the culture medium) are of particular interest. This study aimed to investigate the effect of nutrient medium composition on the growth of V. punctata biomass and the synthesis of polysaccharides by microalgae. The effect of modifying a standard nutrient medium and varying cultivation parameters (temperature, time, and extractant type) on the yield of exopolysaccharides produced by the microalgae V. punctate was investigated. The methods of spectrophotometry, ultrasonic extraction, and alcohol precipitation were used in the study. It was found that after 61 days of cultivation, the concentration of polysaccharides in the culture medium was statistically significantly higher (p <0.05) when using a Prat nutrient medium (984.9 mg/g d.w.) than BBM 3N (63.0 mg/g d.w.). It was found that the increase in the V. punctata biomass when cultivated on different nutrient media did not differ significantly. The maximum biomass values on Prat and BBM 3N media were 1.101 mg/g d.w. and 1.120 mg/g d.w., respectively. Neutral sugars and uronic acids were found in the culture media. It follows on from the obtained data that the modified PratM medium was more efficient for extracting polysaccharides from V. punctata. The potential of microalgae as new sources of valuable chemicals (polysaccharides), which can be widely used in technologies for developing novel functional foods, biologically active food supplements, and pharmaceutical substances, was studied.

Development of a technology for the preparation of a dry nutrient medium for anthrax vaccine production

Currently, submerged cultivation of the Bacillus anthracis STI-1 strain for live anthrax vaccine production requires liquid nutrient media, which have disadvantages of a short shelf life (no more than one month) and a narrow range of storage temperatures (2–8 °С). Dry media, in contrast, have a number of indisputable advantages: such media are transportable and easy to use, have a standard capability to retain properties, and can be stored without preservatives at 2–30 °С for 2–5 years. The aim of this work was to develop a technology for the preparation of a dry nutrient medium for anthrax vaccine production. Materials and methods: The study used the Bacillus anthracis STI-1 vaccine strain and a nutrient medium for its cultivation, containing a 70:30 mixture of an enzymatic digest of casein and a pre-processed corn extract solution. Drying of the nutrient medium was carried out on a spray-drying unit. The authors evaluated physicochemical parameters of experimental medium batches. The shelf life was determined by an accelerated stability study. The dry nutrient medium was used to produce a live anthrax vaccine. Quality attributes of the vaccine were assessed for compliance with regulatory requirements. Results: The authors developed the dry media production technology. According to it, the liquid nutrient medium is fed to the drying unit at a rate of 20–25 dm3/h. The spray air pressure is 0.02 MPa. Temperatures at the drying chamber inlet and outlet are 118–122 °С and 85–90 °С, respectively. The technology was used to obtain 3 experimental batches of the dry medium. The study results demonstrate that the technology is reproducible, and the tested quality attributes of experimental medium batches are consistent with the requirements. According to the accelerated stability study, the shelf life of the dry nutrient medium at 2–30 °С is at least 3 years. Experiments demonstrated the possibility of using the dry nutrient medium for live anthrax vaccine production. Critical quality attributes of the vaccine obtained with the medium met regulatory requirements. Conclusions: The developed technology allows for the production of a standard dry nutrient medium with a prolonged shelf life, which is convenient for live anthrax vaccine production.

Growth Optimization and Secondary Metabolites Evaluation of Anabaena variabilis for Acetylcholinesterase Inhibition Activity.

Cyanobacteria comprise a good natural resource of a potential variety of neuro-chemicals, including acetylcholinesterase inhibitors essential for Alzheimer’s disease treatment. Accordingly, eight different cyanobacterial species were isolated, identified, and evaluated on their growth on different standard nutrient media. It was found that the modified Navicula medium supported the highest growth of the test cyanobacteria. The effects of methylene chloride/methanol crude extracts of the test cyanobacteria on acetylcholinesterase activity were examined and compared. Anabaena variabilis (KU696637.1) crude extract recorded the highest acetylcholinesterase inhibition (62 ± 1.3%). Navicula medium chemical components were optimized through a Plackett–Burman factorial design. The biomass of Anabaena variabilis increased significantly when grown on the optimized medium compared to that of control. The chemical analysis of the fractions derived from Anabaena variabilis showed the presence of two compounds in significant amounts: the flavonoid 5,7-dihydroxy-2-phenyl-4H-chrome-4-one and the alkaloid 4-phenyl-2-(pyridin-3-yl) quinazoline. Molecular docking studies revealed that both compounds interact with the allosteric binding site of acetylcholinesterase at the periphery with π-π stackings with Tyr341 and Trp286 with good, predicted partition coefficient. The compounds obtained from this study open the door for promising drug candidates to treat Alzheimer’s disease for their better pharmacodynamics and pharmacokinetic properties.

RESEARCH OF AMYLOLYTIC ACTIVITY OF CULTURAL LIQUIDS IN BIOTECHNOLOGY OF SYMBIOTIC CROPS МЕDUSOMYCES GISEVII AND ORYZAMYCES INDICI

Based on the literature review found that the natural symbionts Medusomyces gisevii and Oryzamyces indici biotechnology are a valuable objects. It is urgent to find ways to impact on it in order to obtain these or other products of its life activity.&#x0D; At present, it is urgent to search for microorganisms producing enzymes, including amylase. One of the most promising in terms of biological objects is a natural microbial symbiont Medusomyces Gisevii (tea fungus) and Oryzamyces Indici, which, thanks to the not identical, microbiological composition and different growing conditions may have a different composition of metabolites. Studies of the amylolytic activity of the culture liquid Medusomyces Gisevii and Oryzamyces indici with different cultivation periods have been carried out. Cultivation of the fungus was carried out in the laboratory according to the classic method. The optimal concentration of sucrose for Medusomyces Gisevii and Oryzamyces Indici biomass growth was set at 5%. Sucrose concentration of 15% and above is not recommended for use due to inhibition of biomass growth with increasing concentration of carbohydrates in the culture medium. It is established that these symbionts start to show the amylolytic activity already on the 10th day of cultivation cultivation in standard nutrient medium, medium supplemented with 10 % milk and serum-based medium and stores it in the course of the experiment (30 days). Over time the amylolytic activity increases. However, the intensity of metabolism of the microorganisms, the criterion of which is the ratio of the total and exogenous amylase is most pronounced in the early stages of cultivation. It was found that the culture medium of polycultures shows high amylolytic activity. This fact allows us to consider the Medusomyces Gisevii and Oryzamyces Indici inoculum as a promising biotechnological raw material source of amylase enzyme.&#x0D;

Urease production using corn steep liquor as a low-cost nutrient source by Sporosarcina pasteurii: biocementation and process optimization via artificial intelligence approaches.

To commercialize the biocementation through microbial induced carbonate precipitation (MICP), the current study aimed at replacing the costly standard nutrient medium with corn steep liquor (CSL), an inexpensive bio-industrial by-product, on the production of urease enzyme by Sporosarcina pasteurii (PTC 1845). Multiple linear regression (MLR) in linear and quadratic forms, adaptive neuro-fuzzy inference system (ANFIS), and genetic programming (GP) were used for modeling of process based on the experimental data for improving the urease activity (UA). In these models, CSL concentration, urea concentration, nickel supplementation, and incubation time as independent variables and UA as target function were considered. The results of modeling showed that the GP model had the best performance to predict the extent of urease, compared to other ones. The GP model had higher R2 as well as lower RSME in comparison with the models derived from ANFIS and MLR. Under the optimum conditions optimized by GP method, the maximum UA value of 3.6 Mm min-1 was also obtained for 5%v/v CSL concentration, 4.5 g L-1 urea concentration, 0 μM nickel supplementation, and 60 h incubation time. A good agreement between the outputs of GP model for the optimal UA and experimental result was obtained. Finally, a series of laboratory experiments were undertaken to evaluate the influence of biological cementation on the strengthening behavior of treated soil. The maximum shear stress improvement between bio-treated and untreated samples was 292% under normal stress of 55.5 kN as a result of an increase in interparticle cohesion parameters.

Influence of Different Types of Land Use on Prokaryotic Communities and Organic Matter Stabilization in Soddy-Podzolic Soil

The influence of crop rotation with different saturation with legumes and continuous grain crops (winter rye and spring barley) on the structure of prokaryotic communities and preservation of soil organic matter has been studied in a long-term stationary experiment (1977–2018) on a soddy-podzolic soil (Eutric Albic Retisol (Abruptic, Loamic, Cutanic)) of Perm oblast. Permanent black fallow and unmanaged fallow were used as reference standards. Minimum values of the coefficients of mineralization (0.37) and pedotrophicity (0.28) calculated on the basis of direct counting of microbial colonies cultivated on standard nutrient media (MPA, SAA, and SA) have been found in the unmanaged fallow soil, and maximum values of these coefficients (1.97 and 1.30, respectively) were found in the black fallow soil. Inverse relationships were found between the Corg content in the soil and the mineralization coefficient (r = –0.67; p crop rotation (0–28.6–42.9% of legumes) > continuous grain crop > permanent black fallow, In the cultivated and black fallow soils, along with general decrease in the organic matte stock, its lability increased as evidenced by the Cha : Cfa ratio (0.55–0.79), which were lower than in the unmanaged fallow soil (0.96). The closest negative correlation (r = –0.81; p < 0.001) was observed between the mineralization coefficient and the Cha : Cfa ratio. It has been also shown that different uses of soddy-podzolic soil were accompanied by structural rearrangements of the actinomycetal complex selected as a model group of soil microorganisms. In particular, regular mechanical tillage and application of mineral fertilizers (N60P30K60) contributed to an increase in the species spectrum of streptomyces, a change in the frequency of occurrence and relative abundance of individual sections and series, and a change in dominant forms. The results of this study demonstrated the possibility of using microbiological indicators as biomarkers of the state of soil organic matter.

Preparation of rabbit kidney immortalized cell culture

Preparation of immortalized cell lines obtained from organs and tissues of farm animals is an essential area of biotechnology. The paper presents results of continuous (immortalized) cell line preparation from a primary trypsinized cell culture of an adult rabbit kidney. Cytomorphologic analysis and karyotyping were performed during the process of subcultivation in the cell culture at passages 1, 3, 24, 31, 38, 56, 66, 75, 86, 101. Dynamics of spontaneous continuous cell line formation during long-term serial passaging was examined using standard nutrient media and fetal serum. Contrary to the known cell lines of rabbit origin (Oryctolagus cuniculus L.), immortalization was not accompanied with enhanced cell production and cell size reduction. The prepared continuous cell line in its adhesive phase was up to 200 µm in size and its productivity was about 7,000 cells/cm2. Significant differences (compared to the known cell lines) in the karyotype were detected during passaging. The formed genotype was found to be near-tetrapioid when the CCL cultural properties were stabilized at passages 66–101. The known cell lines – rabbit kidney (RK-13) and rabbit cornea (SIRC) – can be characterized as pseudotriploid basing on their karyotype. This culture demonstrated low sensitivity to viruses – causative agents of rabbit diseases and sensitivity to heterologous porcine and bovine viruses.

Сравнительное изучение ростовых параметров и лигноцеллюлолитической активности девяти штаммов Sarcodontia crocea на четырёх разных питательных средах

The results of a study of growth characteristics, macromorphological features and biosynthetic potential of nine dikaryotic strains of Sarcodontia crocea (Polyporales, Basidiomycota) maintained in the Komarov Botanical Institute Basidiomycetes Culture Collection (LE-BIN) are presented. The strains studied were extracted from the basidiocarps collected on Malus domestica in the Belgorod, Oryol and Rostov Oblasts, as well as by seeding of basidiospores. The cultural and morphological characteristics and enzymatic activity of S. crocea were tested on both standard nutrient media (malt-extract agar – MEA, glucose-peptone agar – GPA) and modified semi-synthetic agarized media. Original compositions has been developed and for the first time nutrient media pre-pared using water-based wood extracts from Malus domestica (Malus-M) and Pyrus communis (Pyrus-M) have been approved. It was found that a significant reduction in growth rates was observed during the cultivation of S. crocea on agarized nutrient media of GPA, Malus-M and Pyrus-M. The studied strains on Malus-M and Pyrus-M exhibited high colony variability, sparse micelian mat, and loss of zonality and air mycelium intensity compared to MEA. It was shown that the composition of the nutrient medium strongly determined the ability of S. crocea strains to produce lignocelluolytic complex enzymes. The cellulolytic activity was noted for strains on all media studied, but no reliable differences were found in the cultivation of strains on sugar-rich MEA and three other semi-synthetic media. Only two strains (LE-BIN 2138 and 4355) were identified as having high cellulolytic activ-ity when grown on MEA. The absence of lignolytic complex enzyme activity was demonstrated when the strains were cultivated on new modified semi-synthetic agarized media of Malus-M and Pyrus-M.

Experimental Evaluation of Effects of Electromagnetic Radiation of Extremely High Frequency on the Developing Organism

Introduction: The article is devoted to the results of an experimental study of the variability of indicators of the signs of different levels of importance (population, organismal, and molecular genetic) in order to assess the impact of electromagnetic radiation of extremely high frequency (EHF EMR) as one of the physical environmental factors affecting the human body. Materials and methods: The studies were carried out on the laboratory population of Drosophila melanogaster of the wild phenotype line (D-32). The fruit flies were grown in a standard nutrient medium in special vessels at the temperature of 24.0 ± 0.1 °C in a ТС-80М thermostat subject to the necessary conditions. Results: The model genetic object revealed the effects of the factor that determined the patterns of variability of the number of individuals in the population, their body weight and the RNA content in the body depending on the dose of EHF EMR under different forms of its regulation: at the level of functional asymmetry and in the genotype-medium context. Conclusions: It was demonstrated that radiation of extremely high frequency as a factor of natural and anthropogenic origin influencing vital signs of a developing organism requires attention in a comprehensive hygienic assessment of health effects of environmental factors. This approach is necessary in view of the modifying effect of EHF EMR with respect to the viability of individuals reflecting the morphophysiological and molecular genetic state of the parent generation and its offspring.