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Abstract. Rapid and economical tests based on the bioluminescence inhibition reaction of genetically engineered strains with an integrated luminescence gene have found practical application in various fields, including toxicology, ecology, and bacteriology. Their diagnostic potential suggests a wider use in determining the bacteriotropic properties of a wide range of substrates and preparations of various origins. In this work, we tested a testing method using the Escherichia coli lum+ indicator strain with an integrated lux-operon to determine the nonspecific antibacterial activity of bacteriophages and a preliminary assessment of the prebiotic properties of the plant substrate, an aqueous extract of oats. As a well-known model, a metabolite preparation was used - a cell-free ultrafiltrate of the culture liquid of lactobacilli of the Lactobacillus plantarum 8P-A3 strain with a pronounced inhibitory activity. It has been established that the reaction of the test culture makes it possible to determine the stimulating or inhibitory effect on bioluminescence, as well as its dose dependence. The change in the luminescence of the indicator strain under the influence of bacteriophages developed similarly, including the transition from luminescence quenching in the initial period of joint exposure to its stimulation later by 24 h. physiological state of the test strain in the first hours of joint exposure followed by luminescence stimulation. It seems rational to consider the indicator strain in the study of plant substrates as a model representative of the microbiota of the gastrointestinal tract of a macroorganism. Thus, the tested version of testing can be recommended for determining the bacteriotropic properties of the studied and similar objects.

The immobilization of the cages which are a part of pro-biotic medicines is directed to achievement of a number of the biological and technological effects increasing quality and, respectively, consumer proper-ties of products. The biological effect at different ap-plication of sorbents is caused by increase in re-sistance of a probiotic to action of bactericidal fac-tors of a GIT (gastric juice, bile). The positive techno-logical aspect of an immobilization is connected with achievement of more expressed resistance of cages to physical impacts: to freezing, thawing, drying and other manipulations with bacterial cultures during production. Besides the specified effects, at approba-tion of new sorbents their influence on persistence of specific activity of the immobilized cultures in the course of storage of medicines attracts interest that has the big practical importance for definition and a regulation of an expiration date of a probiotic. Ap-proved as the carrier гомогенат laminarias makes positive impact on stability of the lyophilized culture of bifidobacteria.

Introduction. E. coli strains are the main microorganisms used for the production of a number of important biopharmaceutical products. There are no natural sources of microwave radiation on Earth, as it is absorbed by the upper atmosphere. No one doubts the importance of studying the biological effect of microwave radiation. The number of publications devoted to this problem is growing every year, and new ideas for the use of microwaves in drug production technology are emerging.Aim. Reveal the main effects of microwave irradiation and develop a technology for microwave intensification of E. coli culture growth.Materials and methods. This study presents the results of atomic force microscopy, refractometry, NMR relaxometry, turbidimetry, and lumimetry, demonstrating the possibility of microwave intensification of the cultivation process.Results and discussion. It was found that microwave irradiation leads to changes in the mobility of protons and the adsorption of water molecules on biopolymers and cells. These are the main links in the mechanism of "non-thermal" microwave action. A single microwave irradiation, depending on a number of parameters, can decrease or increase the growth of biomass. Studies of the bioluminescence of the E. coli strain with the lux-operon have shown that the optimal processing conditions do not negatively affect the luciferase production and metabolic activity of cells. Conclusion. The intensification procedure using microwave radiation can be considered a promising method and can provide new ideas for various applications in biotechnology.