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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 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).

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.