PH EFFECT ON ANTAGONISTIC ACTIVITY TOWARDS BACTERIA OF YEASTS ISOLATED FROM HUCUL DAIRY PRODUCTS AND GASTROINTESTINAL TRACT OF HUMAN.

The aim of this work was to study the influence of pH of medium on antagonistic ac- tivity of isolated from authentic Hucul dairy products and gastrointestinal tract (GIT) of Hucul long-livers yeasts towards potentially harmful for humans and animals bacteria. Among 52 tested yeast isolates 14 % yeasts showed considerable antagonistic activity towards Gram-positive bacteria Staphylococcus aureus and only 6 % of them inhibited growth of Gram negative bacteria belonging to genera Escherichia and Citrobacter Most ofyeasts with antagonistic activity (over 70 %) were isolatedfriom long-livers GIT There were identifed two optimal for antagonism areas of pH values of nutrient medium for tested yeasts being around 5.5 and 6.0 for Gram-positive bacteria and around 6.0 and 6.5 for Gram negative bacteria. It appeared that isolated fiom Hucul yogurt Saccharomyces pasterianus yeasts manifested their antagonistic activity in more acidic conditions com- pared to isolates fiom GIT.

ETHANOL PRODUCTION FROM STARCH BY YEASTS ISOLATED FROM CROPS AND DAIRY PRODUCTS.

The aim of this work was to study the ability ofyeasts isolated from crops and dairy products to convert starch to ethanol. The isolated yeasts were screened for their ability to hydrolyze starch. Six most active strains were identified as Lipomyces mesembrius spp. 5.4, 5.5 and 6.4, Shwanniomyces vanrijiae var yarowii F33, Torulaspora sp. F7 and Candida sp. S26. The selected yeasts produced low levels of ethanol from starch under aerobic conditions - 0.006-0.129 g/l (0.3-0.87 % of theoretical yield) and microaerobic conditions - 0. 089-0.35 g/l (1.61-6.07 % of theoretical yield). These amylolytic yeast strains will be studied as the potential candidates for the cocultivation with efficient ethanol producers which do not possess the ability to directly hydrolyze starch.

[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.

Complex Identifcation of Red Yeast Isolate from Gastrointestinal Tract of Hucul Long-Liver (Carpathians, Ukraine).

The red yeasts are currently widely discussed and controversial group of yeasts because of the growing number of reports of their ability to become opportunistic pathogens of plants, animals and humans. The aim of this work was complex identifcation of the red yeast culture isolated from gastrointestinal tract of healthy Hucul long-liver from the Carpathians highland region of Ukraine. Torularhodin was found to be a major component within yeast culture carotenoids complex. According to conventional biochemical and morphological approaches as well as to molecular biological investigation of internal transcribed spacer region (ITS) of ribosomal operon it was concluded that isolate belonged to species Rhodotorula mucilaginosa.

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.

Biodegradation of Petroleum Hydrocarbons by Actinobacteria and Acinetobacteria Strains Producing Biosurfactant.

Environmental pollution with petroleum hydrocarbons has become one of the most urgent problems worldwide. The effectiveness of bioremediation of oil pollutions is significantly affected by the inherent capabilities of microorganisms and their specific adaptive mechanisms of hydrocarbon assimilation. In this study the hydrocarbon biodegradation efficiency and the surface-active properties of the hydrocarbon-oxidizing strains of Gordonia rubripertincta IMB Ac-5005, Rhodococcus erythropolis IMB B-7012 and Acinetobacter calcoaceticus IMB B-7013 were determined. These strains showed high efficiency of biodegradation of n-hexadecane (82.1­86.7 %), kerosene (72.5­80.3 %), diesel fuel (70.1­74.3 %) and crude oil (63.5­68.9 %). The mixed culture of these strains completely assimilated n-alkanes C9­C21 as well as iso-alkanes C8­C17 and significantly decreased (150­230 times) the amount of n-alkanes C22­C26 in the process of cleaning up water from raw oil. The utilization of hydrocarbons by G. rubripertincta IMB Ac-5005 and R. erythropolis IMB B-7012 with low initial hydrophobicity index (2.4 and 9.6 % respectively) was accompanied by the increase in cell surface hydrophobicity (4 and 25 times respectively) and by the synthesis of cell-bound biosurfactants forming stable emulsions of "oil-in-water" type. The dominating components of these biosurfactants were glycolipids: mono- and dimycolates of trehalose. The assimilation of hydrocarbons by highly hydrophobic A. calcoaceticus IMB B-7013 with the initial hydrophobicity index 99.4 % resulted in the decrease of this value by 1.4 times and the synthesis of extracellular biosurfactant forming stable emulsions of "water-in-oil" type. The biosurfactant of A. calcoaceticus IMB B-7013 is similar to emulsans according to its chemical composition and ratio of the main components (carbohydrates, proteins and lipids). The experimental data provide grounds for efficient using of these strains in the process of bioremediation of oil-polluted water and soils.

ANTIMICROBIAL ACTIVITY OF EXTRACTS FROM ECUADORIAN LICHENS.

Antimicrobial activity of the ethanolic, isopropanolic, acetone, DMSO and aqueous extracts of the two lichen species from Ecuadorian highland, Usnea sp. and Stereocaulon sp. were explored in vitro against bacteria Bacillus subtilis, Escherichia coli and Staphylococcus aureus by the disc-diffusion method. Also the minimal inhibitory concentration (MIC) was determined. The strongest antimicrobial activity was found in DMSO extract of Usnea sp. compared to antibacterial activity of ciprfloxacin and cefazolin antibiotics. The inhibition zone was 28 mm, 30 mm, 31mm (DMSO extract, ciprfloxacin and cefazolin respectively) in case of B. subtilis usage as the test bacteria. MIC value for Usnea sp. and Stereocaulon sp. DMSO extracts was 0.4 mg/ml. E. coli was resistant to all kinds of extracts. The S. aureus sensitivity to lichen DMSO extracts was comparable to sensitivity of these microorganisms to tetracycline and vancomycin. Thereby, most kinds of extracts (ethanol, isopropanol, hexane, DMSO and acetone solvents) from Ecuadorian lichens Usnea sp. and Stereocaulon sp. with the exception of aqueous Stereocaulon sp. extracts possessed antibacterial activity against B. subtilis. DMSO lichen extracts had also antimicrobial activity against S. aureus. At the same time the extracts studied didn't demonstrate antibacterial activity against the representatives of the most common and harmful phytopathogenic bacteria tested. Further investigations of Ecuadorian lichens especially study of plants collected from extremal highland biotops can be very important in study of possibility of treatment of numerous diseases caused by pathogenic microorganisms.

Autecology of microorganisms of typical Ecuador biotopes.

34 strains of aerobic chemoorganotrophic microorganisms were isolated from 23 soil and plant samples selected from highland biotopes of Ecuador-Andes massif (Papallacta, 4020 m), ash at the foot of the volcano Tungurahua, mountainous jungle (La Favorita, 1600 m), as well as in humid tropic botanical garden (state Puyo, 950 m). In mountain jungle samples the high number of bacteria--10(5)-10(7) CFU/g of sample were represented by 2-5 morphotypes. In highland (4020 m) samples the bacterial counts made from 10(2) to 10(7) CFU/g of sample. The current study describes resistance of isolated strains to high salinity, UV radiation and toxic metal ions. The majority of isolated strains were halotolerant. Isolates from volcanic ash showed high resistance level to UV radiation--LD99,99 made 1000-1440 J/m2; resistance level for isolates from the soil of Puyo Botanical Garden and isolates from rock lichen (Papallacta) LD99,99 made 1160 and 800 J/m2 respectively. Strains isolated from mountain jungle (La Favorita) showed lower UV-resistance. In highland biotopes of Ecuador occurred bacteria resistant to toxic metal ions. The highest resistance to Hg2+ was shown by isolate of lichen from mountain jungle, the maximal growth concentration was 0.025 g/L; to Cr(VI)--by isolate from lichen rock massif--3,0 g/L. Correlation between metal-resistance, halotolerace and UV resistance for studied strains was not detected, probably because of different microbial cell damage/repair mechanisms under the action of these factors.

The effect of Lacto- and Bifidobacteria in monoculture on the vaginal microflora in norm and in cases of intravaginal staphylococcosis.

The influence of probiotic strains of Lactobacillus casei IMV B-7280, Lactobacillus acidophilus IMV B-7279, Bifidobacterium animalis VKL, Lactobacillus delbrueckii subsp. bulgaricus IMV B-7281 and Bifidobacterium animalis VKB, each strain separately, to the range of the urogenital tract microflora in physiological norm and in cases of experimental intravaginal staphylococcosis of mice induced by Staphylococcus aureus 8325-4. It was found that all these strains had different efficiency in Staphylococcus aureus 8325-4 growth suppression in the vagina of infected mice and affect the spectrum of microorganisms. Lactobacillus casei IMV B-7280 strain had effective antistaphylococcal effect and reduced the number of coliform bacteria and fungi in the vagina in cases of intravaginal staphylococcosis of mice. Lactobacillus casei IMV B-7280 strain is promising to create probiotic drugs effective in treating intravaginal staphylococcosis.

The effect of lacto- and bifidobacteria compositions on the vaginal microflora in cases of intravaginal staphylococcosis.

The effect of intravaginal injection of Lactobacillus casei IMV B-7280, Lactobacillus acidophilus IMV B-7279, Bifidobacterium animalis VKL and Bifidobacterium animalis VKB strains in various compositions on the range of microflora of the urogenital tract on the model of experimental intravaginal staphylococcosis of mice was determined. It was established that under the influence of various compositions of these strains changes in microflora spectrum occurred: the number of representatives of normoflora increased and the number of pathogenic microorganisms, including staphylococci, streptococci, coliform bacteria and fungi, significantly decreased. It was determined that strains of lacto- and bifidobacteria, that were studied, are prospective components of future probiotic drugs efficient in treating staphylococcosis.

The effect of lacto- and bifidobacteria compositions on the vaginal microflora in cases of intravaginal staphylococcosis.

The effect of intravaginal injection of Lactobacillus casei IMV B-7280, Lactobacillus acidophilus IMV B-7279, Bifidobacterium animalis VKL and Bifidobacterium animalis VKB strains in various compositions on the range of microflora of the urogenital tract on the model of experimental intravaginal staphylococcosis of mice was determined. It was established that under the influence of various compositions of these strains changes in microflora spectrum occurred the number of representatives of normoflora increased and the number of pathogenic microorganisms, including staphylococci, streptococci, coliform bacteria and fungi, significantly decreased. It was determined that strains of lacto- and bifidobacteria, that were studied, are prospective components of future probiotic drugs efficient in treating staphylococcosis.

Effect of probiotic strains of lacto- and bifidobacteria on the activity of macrophages and other parameters of immunity in cases of staphylococcosis.

The immunomodulatory properties of Lactobacillus delbrueckii subsp. bulgaricus IMVB-7281, Lactobacillus casei IMV B-7280, Lactobacillus acidophilus IMV B-7279, Bifidobacterium animales VKL and B. animales VKB strains on the models of experimental staphylococcosis infection in mice were determined. It was found that after the mice, infected with staphylococcus, were treated by some probiotic strains of lacto- and bifidobacteria, a normalization of functional activity of phagoctic cells system and increase of the endogenous interferon production were observed. L. delbrueckii subsp. bulgaricus IMVB-7281, L. casei IMVB-7280, L. acidophilus IMV B-7279, B. animales VKB and B. animales VKL are promising for the development of probiotics, effective against staphylococci and for the immunity correction.