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In recent years the organism of human and animals exposed to the complex of unfavorable factors affecting the normal functioning of the basic vital systems. On the one hand it is the influence of the deteriorating environmental situation, the increase of stressful situations, and on the other - the mass uncontrolled use of chemotherapeutic drugs, including antibiotics. In this connection there is the question how to recover the optimal microflora, i.e. microecology and endoecology of microorganism.
In the scientific literature and official documents related to the problems of microecology, as well as in everyday life the biotherapy becomes more and more popular. In theory this concept exists for a long time and was first described by I.I. Mechnikov who found out the positive effect rendered by lactic acid bacteria on the human organism.
Biotherapy includes the concepts "probiotics", "prebiotics", "probiotic products".
Fuller interprets the concept "probiotics" as live microorganisms. During many years there were several interpretations of the term "probiotic". Lilly and Stillwell used this term for the first time in 1965 to denote the metabolites produced by one microorganisms for stimulation of growth of the other. The term "probiotics" means literally "for life" (in relation to a living organism), unlike the term "antibiotic" ("against life"). Violation of microbiocenosis of human and animal organisms due to wide use of antibiotics led to the appearance of resistance of pathogenic microflora to them. Parker suggested to use term "probiotics" for the designation of natural adjuvants - living microorganisms, which introduction in the organism promotes the maintenance and restoration of the biological balance of its normoflora and it has a positive effect on it. Fuller interprets the concept "probiotics" as live microorganisms which, when administered in animal feed or in the composition of food for man (yogurt), positively affect the organism by the recovery of the intestine’s microflora.
Gibson and Robefroid name probiotics the live microorganisms (e.g., strains of living bacteria in yoghurt) which must be present in large enough quantities, remain stable and viable both at storage and after the introduction into the organism, should adapt to the host and render favorable influence on its health. The same authors suggested for the first time to use the term "prebiotics" along with the term "probiotics". Unlike probiotics, prebiotics are the substances or dietary ingredients that selectively stimulate the growth and biological activity of microorganisms in the intestine, positively influencing, in turn, on the composition of microbiocenosis.
Shenderov with co-authors analyzed the substances that can stimulate the growth of normal microflora and suggested to divide the prebiotics into the following groups:
- monosaccharides and alcohols (xylose, xilobiose, rafinose, sorbitol and other);
- oligosaccharides (lactulose, fructooligosaccharide, galactooligosaccharide, xylooligosaccharide and other);
- polysaccharides (pectins, dextrin, inulin and other);
- enzymes (β-galactosidase of microbial origin, proteases of saccharomycetes and other);
- peptides (soy, milk);
- antioxidants (vitamins of group B, vitamin E, ascorbic acid), and also others biologically active additives - amino acids, herbal extracts, organic acids etc.
Complexes of probiotics with prebiotics substances can be combined, creating new biologically active preparations. Some authors consider that the complexes of probiotics with prebiotics substances can be combined creating new biologically active preparations "synbiotics", in which living organisms are combined with substrates stimulate their growth. In the composition of such preparations the prebiotic must not be involved in the metabolism of the organism but serve as the starting component of its growth.
Thus, briefly describing the new terms and definitions appeared in the sphere of microbiotherapy application, we will consider mainly probiotics, their construction and use with the purpose of normalization of microbial ecosystem in human and animals.
In recent years a huge number of probiotic preparations and scientific publications appeared describing their effectiveness. One of the main difficulties of critical analysis of the available literature data is a great variety of studied microorganisms: Bacillus subtilis, В. licheniformis, В. cereus, Lactobacillus acidophilus, L. delbrueckii subsp. bulgaricus, L. plantarum, L.. fermentum, L..salivarius, L.. casei, L.. rhamnosus, L.. reuteri, Bifidobacterium bifidum, B. longum, B. adolescentis, Escherichia coli, Enterococcus faecium, Streptococcus salivarius subsp. thermophilus, Saccharomyces boulardii and etc. In addition, the authors use different combinations of these microorganisms as well as the forms of application. But to consider these preparations as probiotics we can in that case if any living or dead organisms, their structural components, metabolites, having a positive impact on the functioning of microflora of the owner, promote their better adaptation to the conditions of environment in the particular ecological niche. In this regard, most researchers prefer to use the living cultures of microorganisms in the structure of probiotic. Most often bifido- and lactic acid bacteria are used, in particular Lactobacillus. These probiotics are called classic, because they are based on the cultures isolated from the human intestine and dominant since the first days of life. In addition, Lactobacillus and bifidumbacteria are characterized by a high capacity for colonization of the epithelium of the digestive tract that serves as a protective barrier to the penetration of pathogenic microflora and, in turn, ensures the stabilization of the normal composition of the intestine microbiocenosis.
Probiotic properties inherent to other representatives of the normal microflora. However there is sufficient evidence that probiotic properties, though transient, are inherent also other representatives of normal microflora, the habitat of which is not the intestine but the natural and production substrates. These include representatives of the genera Streptococcus, Lactococcus, Enterococcus, Propionibacterium, Leuconostoc, Lactobacillus, which are part of the ferments for the receiving of fermented milk products with probiotic properties (yoghurt, soft and hard cheeses, curdled milk etc).
Coli was used as a basis of bioproducts already since 1918 in the composition of mutaflora. The efficacy of the preparation was associated with a sharp decrease of toxic substances formation in the intestine under the influence of the normalized intestinal microflora. In the USSR for the development of new probiotic the strain of E. coli M-17 was used, which was grown on milk. "Coli curdled mild" had short shelf life and therefore it did not become widespread.
Currently the new forms of colibacterin were developed: tablets, capsules, suppositories. Coli are also the base of other products - normoflorin, colifloran, sevacol, mutaflor, normoflor.
A number of works devoted to probiotics on the basis of the representatives of the genus Aerococcus. It is also reported about using yeast for the production of probiotics. So, the treatment by the preparation, which includes Saccharomyces boulardii, was effective at intestinal infections caused by Clostridium difficile. The expressed clinical effect was obtained also at the use of Saccharomyces cerevisiae.
In recent years the spore-forming bacteria of the genus Bacillus as the brightest representatives of exogenous microflora attract the attention of researchers. Quite a great number of species in this genus tested as therapeutic agents in the treatment of acute and chronic infections: В. cereus, В. polymyxa, В. coagulans, В. brevis, В. megaterium, В. pumilus, В. Laterosporus etc. However, most fully and comprehensively studied types of B. subtilis and B. licheniformis.
Substantiation of probiotic preparations constructing reveals new aspects of mutual relations of macro - and micro-organism. Abroad the probiotics consisting of several species of microorganisms belonging to different clans become popular. The composition of such probiotics the authors prove by the diversified positive effect on human health. The mechanism of action of the probiotic effect is interpreted in different ways and depends on the composition of the microflora of the probiotic. Scientific substantiation of the constructing of probiotic preparations reveals new aspects of mutual relations of macro - and micro-organism. They basically come to the following: the main thing is safety of the strains intended for their introduction in the composition of probiotics, the presence of antagonistic properties to the competitive, including pathogenic and conditionally pathogenic microflora, the resistance to antibiotics is the most intensively used in antibiotic therapy, the ability of probiotic microorganisms actively to assimilate a wide range of nutrients (for oral probiotics), which are present in the digestive tract as a result of biochemical processes of digestion in the body of humans and animals, the presence of adhesive activity relative to the cells of the epithelium of the digestive tract of humans and animals or to the epithelium of other biotopes for which the probiotic preparations are intended, higher, compared with commensal microflora, specific growth rate of probiotic cultures, allowing them to master the nutrient substrate quickly and consequently to increase the cells productivity of probiotic strains.
Probiotics construct on the ability of strains producing biologically active substances. Permanent presence in a particular habitat (the mouth, intestines, vaginal canal and others) a sufficient number of cells probiotic adhered to its wall, prevents the penetration of pathogenic microorganisms in epithelial cells. In addition, probiotic microorganisms create an unfavorable for pathogens pH of the medium, "winning" the микроэконишу. The disbalance of microflora is graded, which was broken at dysbacterioses.Probiotic strains must be resistant to the logical enzymes of saliva (lysozyme) and to the digestive enzymes (pepsin, lipase), stability to the bile. Probiotics construct also by the ability of strains to produce biologically active substances - vitamins, amino acids, antitoxins, etc.At creation of probiotic preparations the strains should be selected which were tested on simbiotic and stability to survive in adverse conditions. In addition, it is very important that probiotic cultures complement each other on biological activity, showing the effect of synergism in the product when conducting microbiotherapy.It is important when selecting strains take into account their manufacturability in production conditions and stability in the cultivation with the preservation of properties at subsequent technological cycles. This ensures high efficiency of commercial probiotics when using them.
In recent years the works appeared that considerably extended the range of criteria of estimation of biological activity of representatives of the normal microflora, which are offered for introduction of strains in the composition of probiotics. One of the most important criteria is the immunomodulating effect of probiotics. Some researchers have attributed this effect of probiotic cultures to stimulation or production of endogenous interferon. In addition, the search of cultures with the most expressed immunogenic properties is carried out actively.
The probiotics of new generation include preparations which are based on recombinant strains of organisms with set properties.
The development of food using live cultures of microorganisms as dietary supplements attracts most of all. In recent years the great attention of researchers is attracted by the development of food with the use of living cultures of microorganisms as dietary supplements, so-called probiotic products. The strategy in creating of these products primarily aimed to compensate the physiological needs of the organism of a man in separate biologically active substances.One approach to solve this problem is the creation of different products based on milk. The introduction of specially selected cultures of Lactobacillus strains of lactic acid bacteria, bifidobacteria into the structure of dairy products promotes the better assimilation of calcium in the organism of people of different age groups, decreases the level of cholesterol in the blood, provides the physiological needs of the organism in vitamins, amino acids, antioxidants, activates the formation of microbial lactase.Thus, useful properties of sour-milk products with probiotic activity along with antagonism of selected strains of microorganisms of the ferment to the infectious agents are implemented through the stimulation of biochemical processes in the macroonrganism and through the mechanism of non-specific immunostimulation.
Undoubtedly, at present the "gold standard" in biotherapy and prophylaxis of microbiocenosis violations of different biotopes of the human organism is the use of probiotics that regulate the normal microflora of the gastro-intestinal tract. Just probiotics are effective for restoring the balance of normoflora of oral cavity and urogenital system. Probiotics are the important and necessary tool for protecting the organism under the influence of unfavorable ecological conditions, metabolic violation after hormonal, radiation and antibiotic therapy, at acute and chronic diseases and dysfunctions of the digestive system caused by the unbalanced diet, stresses.Download, view promotional material