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In order to study the increase in productivity of natural hydrolase producers B. subtilis (producer of amylolytic and proteolytic enzymes) and T. harzianum (producer of xylolytic and cellulolytic enzymes), the efficiency of various approaches to non-directed induced mutagenesis was studied and their comparative characteristics were carried out. Using chemical and physical mutagenesis, new highly active producers of extracellular hydrolytic enzymes B. subtilis strain MB085-1457, B. subtilis strain MB085-2701, B. subtilis strain MB085-3689, T. harzianum strain MF091-962, T. harzianum strain MF091-2093 and T. harzianum strain MF091-3416 were obtained. Comparison of various methods of induced mutagenesis, namely methods of mutagenesis using nitrosoguanidine and nitrosomethylurea, UV and gamma irradiation showed that the greatest efficiency was achieved after mutagenesis using gamma rays. Various methods of induced mutagenesis can be used not only to create effective schemes for increasing the level of accumulation of target enzymes of producers, but also to obtain new drugs based on highly productive strains of microorganisms with hydrolase activity for the purpose of using them in resource-saving technologies for processing agricultural waste (into useful resources) and reducing the negative impact on the environment.

In this study, we have obtained two enzymes from the group of carbohydrases, cellulase and hemicellulase, secreted by vegetative cells of the B. subtilis strain, and comparatively characterized their properties in order to determine the possibility of further use of the bacillus and its metabolic products as safe biopesticides Homogeneous cellulase with a specific activity of 69.8 U/mg protein was isolated and purified electrophoretically from the culture liquid of B. subtilis by precipitation with ammonium sulfate, ion exchange chromatography, followed by purification by gel filtration. The molecular weight of the native cellulase molecule, determined by SDS-Na-PAGE electrophoresis and gel filtration, was established to be 34.0 kDa, and it was found that the enzyme consists of one subunit. Bacillus carbohydrases functioned in the temperature range (from 40 to 60 °C) and pH values (from 5.0 to 6.0). The enzyme was characterized by high stability of pH values from 3.0 to 9.0 (optimum pH 6.0) and temperatures from 20 to 75 ° C (temperature optimum from 53 to 59 ° C), respectively. A comparative study of the properties of cellulase and hemicellulase from the producer B. subtilis revealed differences in their structure and physicochemical properties: cellulase of the strain was a more thermostable and alkali-resistant protein. These results open up prospects for further study of the B. subtilis strain and its metabolic products - cellulolytic and hemicellulolytic enzymes, for potential use as an environmentally friendly means for the control of phytopathogens of agricultural crops.

The paper presents the results of assessing the effectiveness of a complex feed additive based on halloysite for experimental T-2, afla- and zearalenone toxicosis of white rats in terms of survival, changes in clinical condition, enzyme status of blood serum and spleen ultrastructure. The results presented in the article confirmed the danger of the combined effects of mycotoxins on the body of white rats. The presence of mycotoxins in the feed led to the death of 30.0% of rats with a change in the clinical condition of the surviving animals, a significant increase in the serum levels of aminotransferases, alkaline phosphatase, lactate dehydrogenase, creatine kinase and gamma-glutamyltransferase, as well as changes in the ultrastructure of the spleen. A normalizing effect of a food additive based on halloysite on the studied parameters in experimental combined mycotoxicosis was noted, which was manifested by 100% survival of rats, less pronounced changes in the enzyme status and a protective effect on the ultrastructure of the spleen. This makes it promising for further comprehensive research on productive animal species with the prospect of implementation in animal husbandry as an effective means of preventing combined mycotoxicoses.

This study investigated the combined effects of deltamethrin and T-2 toxin on animals, utilizing bentonite as a prophylactic agent. The research was conducted on white rats, which were orally administered the toxins for 20 consecutive days. Subsequently, clinical, hematological, and biochemical parameters were examined to assess the impact of the toxins on the animals. Based on research results, it has been established that the combined effect of deltamethrin and T-2 toxin with repeated administration is characterized by more severe clinical, hematological and biochemical changes than with separate exposure to toxicants. Accompanied by a decrease in the number of leukocytes, erythrocytes and hemoglobin, a decrease in total protein, glucose and cholinesterase activity. Adding bentonite to the feed as a prophylactic agent at a dose of 2% of the diet has a preventive effect in case of combined poisoning with deltamethrin and T- 2 toxin, and helps to normalize the clinical, hematological and biochemical parameters of animals.

The influence of the composition of the nutrient medium on the yield of biomass and the biosynthesis of agglutinins of the mold fungus strain Rhizoctonia solani RS was studied. At the first stage of research, the agglutinin-producing micromycete strain was grown on liquid nutrient media (potato-glucose (PG), Chapek, Sabouraud) at a temperature of 28°C for 8 days. At the next stage of research, the composition of the culture medium was modified in order to select sources of nitrogen (NH4NO3, (NH4)2SO4, NaNO3, arginine, tryptophan, asparagine, threonine, peptone) and carbon (sucrose, glucose, starch) nutrition. Cultivation of the Rh. solani RS on a liquid PG medium, containing glucose in an amount of 20.0 g/l led to a maximum yield of fungal biomass of 23.58 ± 1.30 g/l and the production of its agglutinins (titer 16384). The studied micromycete strain was characterized by the ability to actively use the amino acids threonine or asparagine when added to the above nutrient medium in an amount of 0.1 mg/ml. At the same time, the hemagglutination activity of the micromycete agglutinins increased twofold (titer 32768) compared to the activity of agglutinins on the PG medium without the addition of amino acids (titer 16384).

In order to study the effect of a number of 6-substituted uracil derivatives on bovine embryo lung cells, experiments were conducted. According to the study, the effect of the studied substances on the cultural and morphological properties of cell was determined by taking into account their viability and proliferation index. In %, it was calculated that viability was determined by the ratio of living cells to their total number. The proliferation index was determined as the ratio of the number of proliferating cells to the number of seeded cells. At 0.1 mM concentration of the compounds studied, a decrease in LEK cell viability was recorded compared to the control group, but this was only the case for compound No. 2. When other compounds were used at doses of 0.1 mM, LEK cell viability increased by 3.0-7.0% compared to controls. Increasing the dose of the compounds studied to 1.0 mM results in a 10.0% decrease in survival in the presence of compounds No. 3 and 6, 16.0% in the presence of compounds No. 2 and 7, 19.0% in the presence of compound No. 4 and 25.0% in the presence of compounds No. 8 and 9.

This paper presents research on the study of the adsorption properties of sorbents of mineral and organic origin. From the research results, it was seen that the maximum adsorption properties for zearalenone at room temperature of 19-21 ° C and pH 7 were shown by sorbents: bentonite of the Biklyansky deposits 34.7%, bentonite of The biklyansky burned 25.3%, bentonite of the tarn-Varna deposits 31.4% Mycosorb 65.7%, Phytosorb 57.5%, zeolite 27.3%, Zookarb 21.2% showed the lowest sorption capacity for zearalenone. In relation to the T-2 toxin, the adsorption properties of sorbents at a temperature of 19-21 ° C and pH 7 showed: Phytosorb 57.5%, bentonite of the Biklyansky deposits 51.7%, bentonite of the tarn-Varna deposits 57.4%, Mycosorb 55.7%, Zoocarb 43.8%, zeolite 36.2%, bentonite of the biklyansky fired 31.4%. According to the results of research, it can be concluded that when the average temperature increases from 20-21 ° C to 38-39 ° C, sorbents significantly increase the adsorption of toxins from 50-70% by such sorbents as phytosorb, Mycosorb, bentonite of the Biklyansky Deposit.

In the present study, we isolated, purified and characterized the lectin of the phytopathogenic fungus Fusarium solani 6 and compared it with the properties of the lectin of the saprophytic strain Fusarium solani 4. Electrophoretically homogeneous lectin was obtained from the mycelium of the fungus F. solani 6 by hydrophobic chromatography and gel filtration. The molecular weight of the native lectin molecule was established to be 30.0 kDa, and it was found that it consists of two identical subunits. Comparison of the physicochemical properties of the lectin of the phytopathogenic strain with the lectin of the saprophytic strain showed that the F. solani 6 lectin was a more thermostable and alkali-resistant protein. F. solani 6 lectin showed affinity for simple sugars, and F. solani 4 lectin - for glycoproteins. In contrast to the lectin of a saprophytic fungus, the treatment of pea seedling roots with F. solani lectin 6 before they were infected with the phytopathogen led to a decrease in the degree of damage to the plant root system and the prevalence of Fusarium. These results open up prospects for further study of the phytopathogen lectin and its potential application as a means of eliciting action.

Fusariotoxins (deoxynivalenol, nivalenol, T-2 toxin, diacetoxyscirpenol, zearalenone, moniliformin, fumonisins) are secondary metabolites of Fusarium species of fungi that parasitize various plants or are present on them as facultative pathogens. The aim of this work was to evaluate the ability of bacteria that have antimicrobial activity against toxin-producing Fusarium species to detoxify toxic fungal metabolites in order to create additives that improve the quality and safety of feed and other agricultural products. A total of 207 bacterial isolates belonging to various genera and species have been studied. The isolate, designated as RF-45, was characterized by a broad spectrum and a high level of antagonistic activity against most species of Fusarium fungi. Based on morphological-physiological and biochemical studies, analysis of the 16S rRNA gene sequence, the RF-45 isolate was identified as Bacillus subtilis. The bacillary isolate was distinguished by its ability to produce various hydrolytic enzymes (CMCase, avicelasa, β-glucosidase, FPase and xylanase) and antimicrobial metabolites (siderophores, bacteriocins and exopolysaccharides), as well as to detoxify toxic fungal metabolites. It was concluded that B. subtilis RF-45 can be used as an object for creating additives capable of decontaminating feed and other agricultural products.

The use of a new form of the probiotic preparation of Bacillus subtilis consisting in emulsion of bacteria in palmitic acid has been studied. When evaluating the effectiveness of probiotics, it was assumed that the content of bacterial DNA in the feces is proportional to their content in the intestine. Analysis of the number of bacterial DNA was carried out by real-time PCR. The results showed a positive effect from the use of emulsified bacteria. It was observed in an increase in the amount of B. subtilis in the intestine and, as a consequence, their DNA in the feces of rats.

Antimicrobial properties of the new strains of micro-organisms isolated from natural sources of various ecological niches in the Moscow region and the Republic of Tatarstan were studied. Antifungal activity of isolates was detected in a test culture of toxin-producing microscopic fungi that can cause animal and plant diseases: Aspergillus flavus, Candida albicans, Fusarium oxysporum and Penicillium spp. Of the 46 studied micro-organisms of genera Bacillus, Lactobacillus, Lactococcus and Streptomyces isolates, there are four strains (Bacillus subtilis, Lactobacillus plantarum, Propionibacterium freudenreichii and Streptomyces spp.) that showed an ability to produce biologically active metabolites with a pronounced antimicrobial potential against phytopathogenic fungi metabolites. Based on the selected four strains, a Bacterial product LRV composition has been created. Scots pine, pedunculate oak and small-leaved linden seedlings with single and double foliar treatment and Bacterial product LRV at a concentration of 10 mL/L led to an increase in the growth of the aboveground part by 31.8, 51.9 and 25.4%, respectively, and the underground part by 25.0, 37.2 and 25.7%, respectively, compared to the control. The weight of seedlings at the end of the study exceeded the control variant by an average of 26.0, 44.0 and 78.0%, respectively. Plant protection Bacterial product LRV use did not have a significant effect on the group of molds that caused the powdery mildew and Schütte disease damage to trees. The Biological product LRV provided plant protection from fungal diseases caused by Lophodermium pinastri Chev. and Microsphaera alphitoides. [ABSTRACT FROM AUTHOR]

The prevalence of microscopic fungi and their metabolites in food raw materials and agricultural products poses a great threat to the population. Many mycotoxins are highly toxic and resistant to various environmental factors. The drugs available on the market do not completely neutralize these toxins. The residues of toxins can pose a threat to farm animals, causing a violation in hematological, biochemical, reproductive indicators, a decrease in weight gain, a deterioration in the sanitary quality of meat, milk and eggs. The comparative studies of the T-2 toxin effect on the biological objects - protozoa and primary cell culture (Stylonychia mytilus and bull spermatozoa) indicate a selective toxic activity of this type mycotoxin. When protozoa exposed to T-2 toxin in a dose of 0.5 mcg/ml, cell death was 19 %. The corresponding figure for a germ cell culture was 34 %. The protective effect of exposure to T-2 toxin on biological models was observed with the use of all studied protective drugs. When using bentonite from the Apastovo deposit of RT, the decrease in the death of protozoa against the background of the influence of T-2 toxin was 15 % higher compared to the control. When using strains of microorganisms B. Subtilis and L. Plantarum together with T-2 toxin, the death of protozoa was 10 % higher than the control. The use of the drug KMBI-3 containing bentonite and strains of microorganisms B. Subtilis and L. Plantarum significantly reduced the toxic effects of T-2 toxin, both on protozoan cells and on primary germ cells. The drug KMBI-3 is a dry powder that has the potential to reduce phytopathogen toxins in food raw materials. [ABSTRACT FROM AUTHOR]

The paper presents the studies in the field of toxin-forming phytopathogens of plant raw materials prevention. The studied isolates can be used as potential agents of biological control of fungal infections (Fusarium, Verticillum, Alternaria, Chaetomium, etc.) in agriculture. In the experiment, when silage was contaminated with the phytopathogen Chaetomium, sanitary indicators deteriorated, namely: the crude protein content when exposed to the phytopathogen Chaetomium became 26 % below control; the concentration of acid-detergent fiber when exposed to phytopathogen became lower than control by 28 %; the moisture content in the second group increased by 11 %; the concentration of dry matter when exposed to phytopathogen became lower than control by 36 %; the silage acidity index when exposed to phytopathogen became higher than control by 22 %; the concentration of lactic acid in the group with the use of the phytopathogen Chaetomium decreased by 20 %, the concentration of acetic acid decreased by 17 % compared to the control group. The use of isolates in corn silage contributed to the improvement of chemical parameters and increased nutritional value. Also, strains of Bacillus spp., Lactobacillus spp. Lactococcus spp. and 5-hydroxy-6-methyluracil can be used in the development of new effective drugs to combat various groups of pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the toxicity indices of several 6-substituted uracil derivatives affecting the lung epithelial cells (LECs) in comparison with methyluracil. The number of dead and live cells was determined by the Trypan Blue staining technique (0.1% solution). The results of the experiments showed that in the case of using Compound VI at doses of 0.1 and 1.0 mM /l, proliferative activity increased by 4 and 20 per cent, respectively. The exposure of the lung epithelial cell line to the above dosage was associated with a 6% increase in the level of glucose uptake as compared to the control group. This effect of Compound VI is determined by the presence of sulfur in the 2nd position. The introduction of an amino group into the 6th position (Compounds III and IV) reduced the viability and proliferative activity of cells. [ABSTRACT FROM AUTHOR]