[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.

[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.

[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.

[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.

[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.

[Probiotic properties of industrial strains of lactobacilli and bifidobacteria].

Lactic acid bacteria and bifidobacteria were isolated from the samples of dry microbial substance "Vivolac" and identified. The lactic acid bacteria were identified as Lactobacillus acidophilus. L. delbrueckii subsp. bulgaricus, L. paracasei. Bifidobacteria belonged to the species Bifidobacterium animalis. Manifestation of biological activity of all studied strains was investigated. It was shown, that adhesive activity of the studied strains depended on the genus of the strain: lactobacilli manifested medium adhesiveness to buccal epithelium (medium adhesive index 2.07-2.26), bifidobacteria manifested high adhesiveness (medium adhesive index 4.11-4.76). Antagonism against pathogenic and opportunistic reference strains was manifested to a greater extent to Pseudomonas aeruginosa. Lactobacilli and Bifidobacteria were resistant to aminoglycosides. Sensitivity of the studied strains to antibiotics did not depend on the genus and species of microorganism. Lactobacillus and Bifidobacterium strains were capable to survive in gastric juice and at different concentration of bile, which is promising for development of probiotic preparations on the basis of these strains.

[Identification of Enterococci strains].

Species identification of enterococci strains isolated from human intestinal tract has been conducted with microbiological and molecular-genetic methods. Results of the phenotypic differentiation have been compared with PCR-analysis results. Accuracy of species identification obtained with the use of 4 traditional test schemes of differentiation and API 20 Strep ranged from 77% to 100% for strains of E. faecium, 11-83% for E. durans strains and 56% for E. hirae strains.

[Antibiotic resistance in enterococci isolated from gastrointestinal tract of long-livers].

The susceptibility of 47 antibiotics including 16 clinically important antibiotics was determined by the disk diffusion method for 58 enterococcal strains isolated from gastrointestinal tract of long-livers in 1978-1981. Among the isolates tested, no resistance to clinically relevant antibiotics was found in 9% of strains, 12% of strains demonstrated intermediate susceptibility to 1-6 clinically important antibiotics, and 79% of strains demonstrated resistance to 1-7 therapeutically important antibiotics.

[Antagonistic properties of enterococci isolated from gastrointestinal tract of long-livers].

The strains with antagonistic activity against indicator strains Pseudomonas aeruginosa, Proteus vulgaris, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumonia, Salmonella enterica were revealed among 58 Enterococcus strains isolated from gastrointestinal tract of long-livers. The influence of different components of MRS medium on the antagonistic effect was established. Antagonistic activity remained on the medium without glucose in 36% of strains, on the medium without tween 80--in 60% of strains, on the medium without sodium acetate and ammonium citric acid--in 65% of strains. The activity both for the lack of K2HPO4, MgSO4 and MnSO4, and in the absence of complex nitrogen sources (peptone, beef extract, yeast extract and hepatic extract) was shown in 76% of strains.

[Physiological properties of enterococci after long-term storage].

The discrepancies were found in some physiological properties of enterococcal strains isolated from gastrointestinal tract of long-livers in 1978-1981 years after long-term storage in lyophilized state. Different results of conventional tube tests obtained before and after long-term storage concerning fermentation of glycerol (38% strains), sucrose (36%), manitol (33%), sorbitol (24%), raffinose (27%), lactose, inulin, xylose (3%) were obtained. When comparing results obtained with the help of API-systems with the data of conventional tube tests it was determined that the discrepancies were most frequently observed in carbohydrate fermentation tests for glycerol (27% cases), mannitol (25%), sorbitol (14%), sucrose (11%), raffinose (12%) and rhamnose (10%). Discrepancies in carbohydrate fermentation tests for lactose, inulin, dulcitol, sorbose, xilose and salicin were observed only in 1% of cases.

[Identification of probiotic lactic acid bacteria strains].

The identification of 5 probiotic strains of lactic acid bacteria has been conducted by the method of analysis of physiological properties, API-testing as well as by molecular-genetic methods. It has been confirmed that 4 strains belong to Lactobacillus plantarum, Enterococcus faecium and Streptococcus thermophilus species. S. thermophilus strain has been reidentified as E. durans. The importance of clear identification of microorganism species which is used in probiotics has been demonstrated.

[Adhesion of various species of lactic acid bacteria depending on the AB0 system blood group].

The influence of the AB0 blood groups on adhesion of different lactic acid bacteria species was studied. From twelve investigated strains of Streptococcus salivarius subsp. thermophilus, Enterococcus faecium, Lactobacillus acidophilus, L. plantarum and L. delbrueckii subsp. bulgaricus species, difference between adhesion average index on erythrocytes of various blood groups was found in two strains. The average adhesion index of the strain E. faecium K-50 in A (II) blood group erythrocytes was higher (AAI = 4.91 +/- 0.26) than in B (III) blood group erythrocytes (AAI = 4.17 +/- 0.33). The strain L. delbrueckii subsp. bulgaricus 4n has displayed a higher adhesive activity in A (II) blood group erythrocytes (AAI = 4.36 +/- 0.13) in comparison with AB (III) blood group erythrocytes (AAI = 3.61 +/- 0.75).