The review presents the characteristics of bacteria of the Lactobacillus family and their abi lity to synthesize various bacteriocins. The classification of bacteriocins of lactobacilli is given, which includes three classes: class I -lantibiotics (peptides with a molecular weight of less than 5 kDa, which contain lanthionine), class II -unmodified bacteriocins, also called nonlantibiotics (heat-resistant peptides , which do not contain lanthionine and have a molecular weight less than 10 kDa), and class III -a poorly studied group of thermolabile proteins with a molecular weight of more than 30 kDa. Lactobacilli are shown to synthesize a wide spectrum of bacteriocins, which demonstrate a variety of actions and are able to inhibit the growth of numerous species of opportunistic gram-positive microflora. The article also provides the examples of bacteriocins produced by Lactobacillus isolated from food products (fermented meat, fish, kombucha, goat milk, koumiss, etc.) and various human biotopes (microbiota of breast milk, intestinal tract and vaginal secretions). Additionally, the review shows the prospects of wide application of bacteriocins synthesized by Lactobacillus in the food and pharmaceutical industries.

The review presents the composition of goat colostrum, antimicrobial, immunomodulatory and antioxidant properties of biologically active proteins of goat colostrum, as well as the prospects of their use in medicine. Due to the presence of a complex of biologically active proteins such as lactoferrin, lysozyme, lactoperoxidase, immunoglobulins, etc., goat colostrum increases the body's resistance to infectious diseases, strengthens the immune system, has an antioxidant effect and antibacterial activity against a wide range of microorganisms, thereby preventing or delaying chronic diseases associated with the oxidative stress. Additionally, goat colostrum bioactive proteins show antitumor activity, antiatherogenic properties, the ability to lower the blood pressure and efficiency in the treatment of rheumatoid arthritis. K e y w o r d s: goat colostrum, protein complex, antimicrobial activity, immunomodulatory properties, antioxidant effect, therapeutic use.

Currently there is a growing need for the development of an environmentally friendly process of synthesis of nanoparticles, during which no toxic chemicals are used. That is why an important area of research in nanotechnology sphere is the synthesis of metal nanoparticles by microorganisms such as bacteria and yeast (detoxification often occurs by reduction of metal ions/formation of metal sulfides). Bacteria are the organism of choice due to their fast growth, high efficiency and low cost. Metal nanoparticles exhibit antimicrobial properties, but the properties of nanoparticles depend on their size and shape, making them specific for different applications. Nevertheless, the desired size and shape of nanoparticles can be obtained by optimizing the synthesis process through manipulating their reaction conditions. Microbial synthesis of nanoparticles is an alternative to chemical and physical methods, as it is non-toxic and biocompatible. Despite the relevance of the application of the “green synthesis” method in the field of nanotechnology, biosynthesis by bacterial organisms has certain disadvantages, such as a high probability of pathogenicity, labour-intensive cultivation, and pollution problems. Ultimately, there is a need to explore more potential microorganisms for the synthesis of metal nanoparticles. The paper provides a review of literature data on the biosynthesis of zinc nanoparticles using lactic acid microorganisms. It was shown that bacteria are capable of synthesizing both extracellular and intracellular nanoparticles in the wavelength range of 315-392 nm. Data on the manifestation of antimicrobial properties by zinc nanoparticles against various gram-positive and gram-negative bacterial microorganisms and micromycetes.

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Introduction. The objective of the present article is to determine the molecular weights of the protein mixture of the cow colostrum. This will lead to the development and production of immuno-prophylactic products for maintaining immunity human body.Materials and methods. Bovine milk was the main material for the study. The test samples have been selected from the first day of calving and during the following three days. Specimen 1 represented the colostrum of the cows from Zhytomyr region (Berdychiv town). Specimen 2 represented the bovine colostrum from Kyiv region (Tetiiv town). Electrophoresis method in the polyacrylamide gel in the Laemmli system.Results. It has been determined that high molecular weight fractions of colostrum contain protein molecules with molecular weights of 160-190 kDa, among which are immunoglobulins. Separate parts of immunoglobulins and other proteins, namely, IgG (55kDa) and IgA (62kDa) heavy chains, secretory component of sIgA, and lactoferrin, have also been found out.The test samples of high molecular weight peptides of colostrum contain the biologically active fragments among which there are mostly immunoglobulins, their parts, proteinsabzymes, other protein fragments. The proteins with the molecular weight of 80, 62, 55 kDa are also determined, they can represent heavy chains (55 kDa) and light chains (25 kDa) of IgG and sIgA. In particular, sIgA is a supermolecular complex consisting of Н-and L-chains of IgA (62, 25 kDa, respectively) and a secretory component (80 kDa). Apart from the secretory component of IgA, the protein molecules with the molecular weight of 80 kDa can be halves of the molecules of immunoglobulins or lactoferrin.Conclusion. The presence of a large quantity of proteins allow using the colostrum in the production of childhood, functional, medical, and prophylactic nutrition; in biotechnologies for the manufacturing of other food products with a special composition; in medicine and pharmacology to produce food-grade coats and capsules for medical substances, dietary food supplements.