[Phylogenetic Analysis of Gene 16S rRNA Nucleotide Sequence of Probiotic Strain Lactobacillus sp. 55].

The identification of probiotic strain Lactobacillus sp. 55 at species level on the basis of analysis of the 16S rRNA gene nucleotide sequences has been done. It has been established that investigated strain belongs to the species Lactobacillus gasseri. The nucleotide sequence of strain Lactobacillus gasseri 55 16S rRNA gene's fragment has been deposited in international database GenBank (NCBI) under number 314159 KT.

Taxonomic Research, Biological Properties and Biosynthetic Activity of Lactic Acid Bacteria and Bifdobacteria Isolated from Various Natural Ecological Niches.

Lactic acid bacteria (LAB) and bifdobacteria play an important role in human health and have wide application in food industry. LAB propagation and high quantity of them in natural substrates testifes that many species of these microorganisms have adapted to the environmental conditions, and specifc ecological niches. Lactic acid bacteria isolated from different ecological niches were identifed using phenotypic and molecular­genetic methods. The species of Lactobacillus plantarum, Enterococcus faecium, E. durans, E. hirae, E. faecalis were identifed among LAB. Bifdobacteria were majorly represented by Bifdobacterium infantis, B. breve, B. animalis, B. bifdum and B. dentium species. The intraspecifc heterogeneity of LAB and bifdobacteria strains isolated from distal part of intestinal tract of people belonging to various age group was investigated. The role of teichoic acids in adhesion of the studied LAB strains to human's buccal epithelium was evaluated. Different biological activities, such as gastric juice resistance, tolerance to bile acids, adhesive properties to macroorganism's epithelial cells, sensitivity to clinically signifcant antibiotics were studied. All of these properties make specifc LAB and bifdobacteria strains to be promising for probiotics and functional foods creation.

[INTERACTION OF LACTOBACILLUS PLANTARUM 337D UKM B-2627 STRAIN CELLS WITH CLAY MINERALS IN VITRO].

OBJECTIVE: To characterize the interaction of Lactobacillus plantaruni 337D UKM B-2627 strain, which has probiotic properties, with kaolinite and montmorillonite. METHODS: The methods of infrared spectroscopy, transmission electron microscopy, the adsorption-structural static volumetric method, microbiological and statistical methods were used. RESULTS: The characteristics of the porous space of clay mineral particles were practically did not change compared with initial samples during the interaction with L. plantarum 337D UKM B-2627 strain cells, pore size distribution had become wider due to the emergence of large diameter pores, reduced surface area, but the adsorption capacity and the layered structure of clay minerals preserved. For the first time the ef- fect of kaolinite and montmorillonite on growth of L. plantaruni 337D strain in vitro was studied. The greatest stimulating effect of clay minerals was observed within two hours of cultivation. The specific growth rate of L. plantaruni 337D strain was in 5.2 times higher when cultured in MRS medium with 4 % of kaolinite and 6 times more - in MRS medium with 1 % montmorillonite versus control. The presence in the medium of kaolinite or montmorillonite slowed the process of reducing pH during growth of the L. plantarum 337D strain, compared with the control. In the presence of montmorillonite pH decreased more slowly than in the presence of kaolinite. The difference between initial pH value of medium with 4 % kaolinite and after two h (ApH) was 10 times less in comparison with the control. At the same time, pH of the medium with 1 % or 4 % montmorillonite began to decrease after 4 hours of cultivation. CONCLUSIONS: Different effect on the growth of L. plantarum 337D strain due to differences of physical and chemical characteristics of kaolinite and montmorillonite used in the study.

[Physiological and biochemical properties of the Lactobacillus plantarum, isolated from traditional fermented products of Ukraine].

Physiological and biochemical properties of the 109 lactobacillus strains, isolated from traditional fermented products of Ukraine, has been investigated. Was showed that the 109 strains isolated from fermented vegetables grew at 10 degrees C, and 23% strains in the medium with 8% NaCl in contrast to the strains of L. plantarum isolated from dairy products. Formation of milk-clot, using strains of the dairy products, occurs within 20 +/- 4 hours, when using strains of the fermented vegetables considerably longer to 48 hours. 22% of strains of L. plantarum did not synthesize biogenic amines. Most of the strains did not produce acetoin, and were sensitive to broad-spectrum antibiotics. Antibiotic resistance of the tested strains did not depend of the source of L. plantarum strains isolation.

[Effect of inorganic phosphate on the properties of Lactobacilli probiotic strains].

The effect of inorganic phosphate in the culture medium on microbial surface hydrophobicity, susceptibility to antibiotics and its autolytic activity has been investigated. The limitation of inorganic phosphate reduced affinity of bacterial cells to chloroform, ethyl acetate and hexane. The total elimination of inorganic phosphate caused an increase of the affinity of Lactobacillus plantarum strain 11/16 to hexane. Autolytic activity of the strain L. plantarum 195D did not depend on the concentration of inorganic phosphate, whereas its decrease reduced autolysis of the strain L. plantarum 11/16 by 15-20% Antibiotic susceptibility decrease of lactobacilli towards to the effect of fuzidin, furazolidone and rifampicin was shown. At the same time, limitation of inorganic phosphate source in the culture medium increased the antibiotic sensitivity towards ceftriaxone.

[Isolation and identification of bacteria of Lactobacillus genus from fermented products in diferent regions of Ukraine].

Seventy one strains of lactobacilli were isolated from fermented animal and vegetable products. Morphological, physiological and biochemical properties of lactobacilli have been studied. Sixty seven strains were identified by molecular genetic methods and classified as Lactobacillus plantarum. Phenotypic and genetic heterogeneity of the isolated strains was shown.

[Antagonistic properties of Lactobacillus plantarum strains, isolated from traditional fermented products of Ukraine].

The antagonistic activity of 109 lactobacillus strains, isolated from traditional fermented products of Ukraine, has been investigated and it has been shown that the significant part of strains show different levels of inhibition of opportunistic and phytopathogenic microorganisms. It has been shown that the antagonistic effect of Lactobacillus plantarum strains on the opportunistic and phytopathogenic microorganisms was dependent on the sources of Lactobacillus strains isolation. L. plantarum strains show a higher level of inhibition against phytopathogenic microorganisms than opportunistic test-strains. Eleven strains of L. plantarum demonstrated antagonistic activity for all used test-strains.

[Antagonistic properties of lactic acid bacteria isolated from apparently healthy and osteoporotic women].

Antagonistic activity of 74 cultures of lactic acid bacteria, isolated from healthy and osteoporotic women-patients aged 50-79 years, has been studied. It has been shown that the inhibitory effect of the strain studied was independent of the health of women (control group of women or patients with osteoporosis), but had strain specificity. Seventeen most active strains of lactobacilli, which showed the highest inhibitory activity against B. cereus, P. aeruginosa, P. vulgaris were selected. Only 6 strains of lactobacillus demonstrated specific antagonistic activity against the test-strains.

[Identification and biological properties of intestinal lactic acid bacteria isolated from aged women].

The strains of lactic acid bacteria have been isolated from the intestine of older women. These strains were identified and their biological activity was studied. It has been established that Lactobacillus acidophilus, L. plantarum, L. salivarius var. salivarius and Enterococcus faecium had the highest antagonistic activity against opportunistic microorganisms. It has been revealed, that the adhesive properties and antibiotic resistance of the tested cultures had strain specificity. Most of the isolates were highly adhesive and did not produce hemolysins.

Antimicrobial activity of bifidobacterial bacteriocin-like substances.

Antagonistic activity of 13 bifidobacterial strains, isolated from humans, has been studied. It was shown that specific antagonistic activity in bifidobacteria is a strain characteristic and does not depend on species of these microorganisms. It was determined that bifidobacteria are able to produce bacteriocin-like substances against both gram-positive and gram-negative bacteria. Strains Bifidobacterium sp. 278 and B. bifidum 174 produced antimicrobial substances of wide spectrum of activity and manifested the highest antagonistic activity as compared to the rest of bifidobacterial strains studied. The maximal activity of bacteriocin production by strains B. bifidum 174 ma Bifidobacterium sp. 278 occurs between 8-16 hours of cultivation that is in the late logarithmic phase of growth. According to obtained characteristics the antimicrobial substances are complex peptides and belong to the 4th class of bacteriocins.

[Microbiocenosis of intestine and nutrition of healthy and osteoporotic aged women].

The composition of microflora of the distal part of intestine of 25 healthy and osteoporotic women-patients aged 50-79 years, depending on their diet, has been studied. The quantitative composition of intestinal microflora of women with osteoporosis, indicates the presence of dysbiosis caused by the decrease in the content of bifidobacteria and lactobacilli and a high level of undesirable microorganisms. The content of 78 nutrients in the diet of the examined women was analyzed. It was shown that the diet of patients with osteoporosis was more calorie rich and included a higher amount of essential nutrients than the diet of healthy women. The indicators of bone mineral density, depending on the number of representatives of nine groups of microorganisms isolated from the contents of the distal part of intestine, were analyzed. It has been well established that with an increase in the number of enterococci in the contents of the distal part of intestine the deterioration of the structural-functional state of the bone tissue can be observed.

[Teichoic acids from lactic acid bacteria].

The current view of the structural diversity of teichoic acids and their involvement in the biological activity of lactobacilli has been reviewed. The mechanisms of effects of probiotic lactic acid bacteria, in particular adhesive and immunostimulating functions have been described. The prospects of the use of structure data of teichoic acid in the assessment of intraspecific diversity of lactic acid bacteria have been also reflected.

[The influence of teichoic acids from probiotic lactobacilli on microbial adhesion to epithelial cells].

The effect of teichoic acids from lactobacillus strains on their adhesion to human buccal epithellium has been studied. It is shown that preliminary treatment of epithellium cells by teichoic acids caused a decrease of adhesion of L. plantarum 11/16, L. plantarum 195D strains by 39 and 30%, respectively. The influence of teichoic acid from lactobacilli on the adhesion of opportunistic microbial strains has been studied. It is established that teichoic acids from both lactobacilli strains brought to the decrease of adhesion of C. albicans to 29-34%. Teichoic acid from the strain L. plantarum 195D stimulated the adhesion of S. aureus 2.25 times, while teichoic acid from L. plantarum 11/16 did not influence the staphylococcal adhesion. There was also no effect of the studied teichoic acid on the adhesion of E. coli.

[Methodical approaches to isolation of teichoic acids from native cells of lactic acid bacteria probiotic strains].

Teichoic acids of lactic acid bacteria probiotic strains have been obtained by extraction from native cells, followed by purification of extracts using ion exchange chromatography. Selected fractions contained high concentrations of phosphorus and did not contain nucleic acids. The content of teichoic acid depended on the species and strain specificity. Heterogeneity of the studied biomolecules was revealed.

[Bifidobacterial species composition of digestive tract of people of different age groups].

The quantitative and species composition of bifidoflora of intestinal content of people of different age groups has been studied. It was established that B. longum subsp. infantis, B. bifidum, B. brev, B. longum subsp. longum and B. dentium were the dominant species of intestinal bifidoflora of people of all ages. The dependence of the species composition of intestinal bifidobacteria on the human age was shown. A decrease of species diversity of bifidobacteria in elderly people was observed.

[Use of real-time PCR for quantitative assessment of lactic acid bacteria and bifidobacteria in dairy products].

Composition of lactic acid bacteria and bifidobacteria in raw milk and home-made milk products has been analyzed using real-time PCR (quantitative PCR) with genus-specific primers to Enterococcus, Lactobacillus and Bifidobacteria. Bacteria belonging to these genera have been revealed in all samples analyzed (milk, sour cream, cottage cheese). It has been shown that the representatives of Enterococcus and Lactobacillus genera dominated in the samples analyzed (10(3)-10(7) genome equivalent/ml (mg)). The largest number of these microorganisms (10(7) genome equivalent/mg) has been detected in cottage cheese.

[Enterocins--diversity, properties and practical use].

This review presents current information about bacteriocinogenic activity of bacteria of Enterococcus genus. Information is presented about enterocins diversitx, their properties, the effect of culture conditions on their production, activity spectrum. Data on the practical use of enterocins as biopreservatives in food products of animal and vegetable origin.

[Intraspecies variability of bifidobacteria colonizing human gastro-intestinal tract].

The results of intraspecies heterogeneity analysis of 4 bifidobacterial species, B. longum, B. animalis subsp. lactics, B. bifidum and B. dentium colonizing intestines of people of different age groups are presented in the paper. A high level of intraspecies variability has been revealed for all species using PCR with primers to short nucleotide repeats. The dendrogram of genetic relationships between bifidobacteria has been constructed on the basis of results of PCR-analysis with the unweighted pair group method of arithmetic mean (UPGMA). Strains analyzed have formed groups according to their species designation.

[Disintegration of lactobacilli and enterococci for obtaining cell wall fragments].

The methods of Gram-positive cells disintegration to obtain cell wall fragments have been described. It has been shown that the use of ultrasonic disintegrator UZD-500 at the frequency 22 kHz during 30 min is optimal for disintegration of lactic acid bacteria cells. Also the ability to use grinding of cells in liquid nitrogen (6 times to the complete evaporation) for obtaining the cell wall fragments has been demonstrated.

[Identification and taxonomy of Enterococci].

Enterococci belong to lactic acid bacteria group. Wide distribution and a variety of their properties are of interest for researchers for a long time. Genus Enterococcus is a group of bacteria heterogeneous by their phenotypic characteristics. The review presented the current status of question concerning enterococci taxonomy that has undergone significant changes during the last decades. Microbiologic methods of identification are considered and analyzed. Special attention was given to the problems that may occur during genus identification of enterococci and during differentiation of closely related species. The use of molecular-genetic methods of identification let to overcome disadvantages of phenotypic identification of bacteria genus Enterococcus. The need of the use of molecular methods of identification was shown, basic approaches were listed, their advantages and disadvantages were discussed.