[Extracellular lectins from saprophytic strains of bacteria of the genus Bacillus (review)]

The present review summarizes both the authors' own and other researchers' reports concerning the synthesis and properties of sialic acid-specific extracellular lectins from saprophytic bacteria of the genus Bacillus. Bacilli of this genus isolated from different ecological niches differ with regard to the ability to synthesize lectins. The biphasic temporal pattern of lectin synthesis in culture and the effect of cultivation conditions on lectin production have been demonstrated. The advantages of the technological procedure used for the isolation and purification of these biopolymers have been characterized. Specificity towards sialic acid, which is characteristic only of a small number of lectins from bacilli and underlies a wide range of biological effects of these proteins, receives particular attention. Adaptation mechanisms involving lectins--carbohydrate-recognizing proteins--are suggested to have developed in saprophytic bacilli to ensure the survival of these organisms in a constantly changing environment.

[The ability of actinobacteria to assimilate n-alkanes under nitrate-reducing conditions]

It has been established that the oil-oxidizing strains of actinobacteria--components of the preparation "Ekolan-M" are able to assimilate n-alkanes during microaerobic cultivation in nitrate-reducing conditions. After 7 days of growth in these conditions, the level of biodegradation of n-hexadecane of the investigated strains was 52.0%, which is 1.5 times less than for the same period in the aerobic cultivation. n-Hexadecane utilized by cells was completely mineralized to carbon dioxide, the amount of which in the gas phase reached 1.6% on the 9th day of growth.

[Chromate reduction by Pseudomonas sp. str. 10 in the presence of some heavy metals and alternative electron acceptors]

Pseudomonas sp. str. 10 reduces chromate with a rate of 0.54 mg / L.h. The availability of Cd2+ and Zn2+ in the medium has no noticeable effect on the rate or slightly increases it. The presence of nickel and copper in the ionic form in the medium resulted in a decrease of chromate reduction rate 2.4 and 4.2 times, respectively. Change of these metals into hydroxide form significantly lowers their negative influence. Iron (III) both in ionic and hydroxide form inhibits the reduction of chromate by Pseudomonas sp. 10. Joint presence of all studied metals decreases their negative impact on chromate reduction, therefore these metals may be neutralized together without a significant lowering of the process efficacy on condition that copper-containing drain will be cleaned separately. The presence of alternative acceptors of electrons inhibited the reduction of chromate. Sulfate and oxyanions of chlorine - chlorate and perchlorate have the highest inhibitory effect on chromate reduction.

[Metabolism features of bacteria resistant to high concentrations of chromate]

Twenty strains of bacteria resistant to high concentrations of chromate were isolated from different ecological niches. They were able to reduce chromate to compounds of trivalent chromium--nonsoluble chromium hydroxide or soluble crystalline hydrates of trivalent chromium. The growth features of these microorganisms on media containing chromate at high concentrations (up to 20.0 g/l) are described. Besides chromate bacteria can reduce vanadate to compounds of V(4+) and Mo(6+) to Mo(5+). The best reduction takes place on the media where MPB. glucose or ethanol serves as the source of carbon. The growth and reduction of anion-in-study did not occur on organic acids. It was shown that tungstate, chlorate or perchlorate were not toxic for the studied bacteria up to concentrations of 10.0 g/l, however were not reduced by these microorganisms. The most active strains belong to genera Pseudomonas, Oerskovia, Bacillus, Micrococcus.

[Selection of thermophilic lactose-fermenting yeast strains]

The screening and selection of lactose-fermenting yeasts among 97 collection yeast strains belonging to different taxonomic groups has been conducted to obtain ethanol from whey. The strains (n=18) (1 strain of K. lactis. 16 strains of K. marxianus and 1 strain of C. kefyr) fermented lactose at 48 degrees C and 15 selected strains rapidly consumed lactose within 24-48 h of cultivation. The presence of 6% of ethanol in the medium resulted in a considerable growth inhibition (more than 80%) of the selected strains.

[Efficiency of the preparation "Ekolan-M" for purification of oil polluted soil]

The efficiency of purification of oil contaminated loamy chernozem by the preparation "Ekolan-M" was investigated. During 12 months a complex soil bioremediation using the preparation and alfalfa, as the land-improving plant, at the final stage of purification resulted in the reduction of hydrocarbon content by 97.0%, and without the preparation - by 65.5 %. In the version of experiment with the preparation a 100% decrease of soil phytotoxicity was achieved and a significant stimulation of plant growth and development was observed. The process of soil purification was accompanied by intensive development of hydrocarbon-oxidizing microorganisms, the amount of which during the process of oil concentration gradually decreased, approaching the level in the control uncontaminated soil.

[Geno- and phenotypic characteristic of Bacillus strains--components of endosporin]

Endosporin is used in veterinary for the prophylaxis and treatment of disbacteriosis, intestinal infections, festering wounds and postpartum pyoinflammatory complications in agricultural animals. The probiotic is based on two Bacillus strains which inhibit growth of a broad spectrum of pathogenic microorganisms and synthesise proteolytic enzymes and other biologically active secondary metabolites, particularly - polysaccharides. The activity of these two strains was supplementary. For the species identification of these strains, sequences of 16S rRNA genes and fatty acid content of cell walls were analysed. It was found that the both strains belong to B. velezensis. Limitations of application of 16S rRNA sequences for identification of closely related species are discussed in the paper. A method of 16S rRNA sequence profiling by polymorphic nucleotides was proposed. It was also shown that usefulness of Bacillus strains in probiotics is mostly based on their unique strain specific properties rather than on general species characteristics.

[Reduction of chlorate in the presence of heavy metals by Acinetobacter thermotoleranticus C-1]

Influence of heavy metals on Acinetobacter thermotoleranticus C-1 was studied by the rate of chlorate reduction and biomass growth. It was established that Fe3+ in a form of free ion at concentration of 30 mg/l also stimulates both the reduction of chlorate by A. thermotoleranticus C-1 and the growth of biomass, Cd2+ Pb2+ and Mn2+ do not practically affect the process velocity or stimulate it a little, Cu2+ and Zn2+ lower the reduction rate of C10(3)- 2.5-3 times, under these conditions the biomass growth is inhibited more weakly than the reduction rate. Nickel and cobalt in the mentioned amount inhibit completely the process of reduction. Metals in the form of hydroxide-ion proved to be less toxic for str. C-1, than their ion forms. General influence of a free ion, metal hydroxide and the amount of organic nutrition takes more considerable (stimulating or inhibiting) influence on the process, than each of these factors itself.

[Reduction of chlorates by acinetobacter thermotoleranticus C-1 in the presence of chromate ions]

The rate of chlorate reduction by A. thermotoleranticus C-1 reached 59.6-63.7 mg/l an hour and did not practically depend on chlorate concentration in a broad range. Chlorate and chromate being jointly present in the medium, the rate of chlorate-reduction depended on chromate concentration and remained at the same level when content of chromate reached 5 mg/l. Under CrO4(2-) of 10.0 mg/l the reduction of chlorate by A. thermotoleranticus became inconsiderably slower. The increase of CrO4(2-) content to 20.0-30.0 mg/l decreased the chlorate reduction rate from 63.7 to 18.3-5.8 mg/l an hour, and availability of 50.0 mg/l of chromate was the inhibiting concentration for chlorate destruction and led to irreversible loss of the capacity ofA. thermotoleranticus C-1 to reduce chlorate. The reduction of chromate proceeded simultaneously with that of chlorate. The rate of chromate reduction by A. thermotoleranticus C-1 under their content in the medium of 3-20 mg/l was 0.5-0.37 mg/l an hour and decreased considerably with the increase of concentration of chromate-ions. Availability of chlorate had no effect on reduction of chromate by A. thermotoleranticus C-1.

[Reversion of antibiotic-sensitivity of lactic acid bacteria in grafted cultures of lymphoblastoid human cells]

The reversion of the antibiotic sensitivity of lactic acid bacteria: Streptococcus salivarius subsp. thermophilus, Enterococcus faecium, Lactobacillus plantarum have been studied. The phenomenon of the reversion has been fists studied in lactic acid bacteria of different taxonomic groups at their interactions with lymphoblastoid human cells. It is shown that resistance of lactobacteria to antibiotics can change depending on the terms of cultivation, genus and strain specificity. Most often the reversion of antibiotic sensitivity was observed with respect to fuzidin (26%) and cefepim (23%), most rarely--with respect to cephazolin, erithromicin, cefamandol, tobramicin and oxacillin.

[Study of vaginal and intestinal microflora of women in the prenatal period and its correction in dysbacteriosis]

A comparative research of the structure of vaginal and intestinal microflora in norm and at kidney pathologies in women in the prenatal period was carried out. At physiologically normal course of pregnancy microbiocenosis of vagina and intestine does not contain pathogenic and conditional-pathogenic microorganisms. Lactic acid bacteria are fixed within the limits of 10(5)-10(8) CFU/1 ml in the vagina secretion and 10(7)-10(8) CFU/1 g in the intestine content. The spore microorganisms have completely disappeared in vaginal biocenosis of women with pyelonephritis after pharmacotherapy; and colibacterias has disappeared in 62% of women. Quantity of lactic acid bacteria has also decreased. Quantity of E. coli (10(8)- 10(9)) CFU/g, sporous microorganisms (10(3)-10(4)) CFU/g and yeast (10(4)-10(5)) CFU/g has considerably increased in the content of intestine. Lactic acid bacteria in content of the vagina are presented by: Lactobacillus acidophilus, L. plantarum, L. fermentum, L. vaginalis; in content of the intestine--L. plantarum and L. fermentum. All the isolated strains of lactobacilli are resistant to metrogyl and amphotericin, 87%--to cephoxitine, cypropfloxacine. Twenty three of 24 strains of lactic acid bacteria--antagonists of pathogenic microflora have shown adhesion to vaginal epthelium. The degree of adhesive activity depends on the strain and genus specificity of cultures. The highest index of adhesiveness in indicated in Enterococcus faecium (5.82 - 7.62) and Streptococcus salivarius subsp. thermophilus (2.74 - 6.40) strains. The screening of strains has been performed, which suppress growth of gas-producing microflora. The strain of Lactobacillus plantarum 200D proved to be the most active one. A complex of cultures of the lactic bacteria providing normalization of microbial cenosis of the vagina in women in the prenatal period has been selected as based on the data obtained. The biotechnology of production of vaginal suppositories is developed.

[Assessment of probiotics according to the international organizations (FAO/WHO)]

The guidelines of international organizations (FAO/WHO) are presented in the paper for the purpose of estimation of probiotic properties of the strains of microorganisms as well as functional food products in respect of their influence on health. Modern scientific researches served as the basis for minimum requirements necessary for the competence of probiotic status. The chart of the experiment sequence is presented that has to be used for probiotics estimation: bacteria systemizing with the use of phenotype and genetic techniques, description of functional properties of the probiotic and estimation of its safety. The in vitro tests for determination of safety of probiotics are described.

[Interferon induction by lacticacid bacteria in vitro and in vivo experiments]

Interferonogenic acitivity of lacticacid bacteria was studied in experiments in vitro and in vivo. It have been shown, that interferon induction depends both on strain species and on culture medium used for lactobacteria harvesting. Streptococcus thermophilus induces interferon more actively in leucocytes (in vitro)--1280 AU/ml on the bines broth medium, and less actively--320 AU/ml on fermented corn medium. Interferon induction in human leucocytes was not registered in case of L. plantarum 200 strain. In vivo experiments show that E. faecium strain and strain mixture of streptococcus termophilus are active interferon inductors. Induced interferon is recognized as alpha- and gamma-interferon, with domination of alpha-interferon.

[Leaching of calcium, silicon, aluminum and iron from micromycetes grown in submerged culture in the presence of ground concrete]

The leaching of chemical elements from concrete by microfungi of genera Aspergillus and Cladosporium during fungal growth on the medium containing ground barrier concrete under submerged conditions has been studied. It was shown that the leaching of chemical elements depended on the process of growth and metabolites excretion, on fungi species and on concrete concentration on the medium. Specificity of metals mobilization by different fungi was found.

[Protective action of electromagnetic radiation (40.68 MHz) on Saccharomyces cerevisiae UCM Y-517]

Electromagnetic radiation (EMR) (40.68 MHz, 15 and 30 W) has been studied for its effect on survivability of cells of Saccharomyces cerevisiae UCM Y-517 under the extremal influence of the environment factors (pH, freezing-thawing, nistatin (1.0 microg/ml)). It is shown that even short-term irradiation of the yeast suspension (during 5 min) takes protective effect under the conditions of stress factors, displayed in the increase of the number of live intact cells. It was established by cytochemical methods that 50-70 % of cells were characterized as damaged and dead in the control samples after yeast exposition under the stress conditions. Such an effect was not observed in the samples of preliminary irradiated cells. The pool of extracellular nucleotides was shown to decrease as a result of the yeast cells irradiation; one could also observe the decrease of these cells ability to acidity the culture medium. The increase of activity of intracellular enzymes of dehydrogenase complex was noted as well. Stability of electrostatic characteristics of the cell surface (zeta-potential) and catalase activity under the effect of EMR of radio-frequency range has been demonstrated. The found effect of protective action of EMR of the above frequency is of nonspecific character, which allows its mechanism universality to be supposed.

[Adhesion of lactic acid bacteria to epithelium of different cavities of the human organism]

During investigation of adhesive properties of lactic acid bacteria it was found out that 11 strains adhered to buccal intestinal and vaginal epithelium of human. The highest adhesive activity was detected in enterococci (adhesive index 7.75-14.26), lower one--in streptococci (6.40-9.16). In lactobacilli adhesive properties manifested in different ways: Lactobacillus acidophilus strains adhered more often to buccal epithelium (2.58-4.60) and rarely--to intestinal and vaginal. L. plantarum manifested high adhesive activity (8.03 -9.69) to buccal epithelium and lower one--to the rest of epithelium types. Monosaccharide composition of glycocalix of 6 strains of lactic acid bacteria was studied to understand the adhesion mechanism. It was shown that surface structures of this microorganism interact with plant lectins, specific to certain monosaccharides.

[Effect of chromium (VI) on growth physiology and sorptional capacity of yeast]

Resistance of 7 yeast species (7 strains) to various chrome concentrations in the medium and their sorptional activity have been studied. It is shown that the biomass of the yeast Williopsis californica UKM-248, Candida krusei UKM-61t under their concentration in the medium of 200 and 500 mg/l of Cr6+ is 0.74 and 0.45 g/l DWB, respectively. For the rest of strains these chrome concentrations are toxical and the concentration of 100 mg/l of Cr6+ is the bordering threshold for them. Under periodical cultivation in the medium with 30 mg/l of Cr6+ one can observe the delay of cultures growth displayed in the increase of the lag-phase and exponential growth phase as well as the decrease of medium pH (to 2). The resistance of the studied yeast to high concentrations of Cr6+ correlates with their sorptional activity.

[Effect of radio-frequency electromagnetic radiation on physiological features of Saccharomyces cerevisiae strain UCM Y-517]

Effect of electromagnetic radiation (40.68 MHz) on growth characteristics of Saccharomyces cerevisiae strain UCM Y-517 has been studied. Reliable increase of the specific growth rate (by 7-15%) and change of duration of growth phases as a result of irradiation of yeast population has been shown. The EMR effect has been found to depend on physiological state of the irradiated cells and composition of the irradiation performance medium: reliable effects were found only for the cells preliminarily grown on the dense nutrition medium in the late phase of delayed growth or on achieving the stationary growth phase. The role of radiation term and power as well as of temperature factor in EMR effect on the cells is discussed. It has been noted that the dependence of specific growth rate of yeast on the initial density of cells population acquire the nonlinear character as affected by EMR of radiofrequency range.

[Search of heavy metals biosorbents among yeasts of different taxonomic groups]

The use of microbial cells as heavy metal biosorbents is a potential alternative for the existing methods of the environment treatment for pollution by these metals. Yeast may be successfully used in the metals sorption. An agar-plate screening method was used for rapid isolation of metal-accumulating strains of yeast and preliminary estimation of their biosorption capacity. The capacity to accumulate heavy metals, such as copper, zinc, lead, chrome and cobalt was estimated in 68 pigmented and pigmentless yeast strains isolated from different sources. The best capacity of copper and zinc accumulation was shown by pink-coloured Rhodotorula mucilaginosa, Rhodotorula aurantiaca, Rhodotorula glutinis and pigmentless strains of the yeast Candida krusei, Williopsis california.

[Yeasts--biosorbents of heavy metals]

The sharp increase of the level of environment pollution by heavy metals caused the increase of interest to the problem of live organisms (including microorganisms) resistance to these metals. Biosorption is one of the mechanisms of microorganisms resistance to heavy metals. Yeasts as biosorbents are of special interest. An analysis of the data from literature have shown that the yeast biomass may be used successfully as biosorption material for such metals as Ag, Au, Cd, Co, Cr, Cu, Ni, Pb, U, Th, Zn. Yeasts of genera Saccharomyces, Candida, Pichia are efficient biosorbents of metals. The sorptional system estimation is based on the classic sorption isotherm obtained in the course of equilibrium experiments and depends on pH, properties of metal ions, biomass concentration, preliminary physical or chemical treatment of the biomass, presence of various organic and inorganic ions and on temperature. The yeast biomass may be obtained using numerous industrial processes, that decreases considerably the biosorbent cost. Most yeasts can sorb a wide range of metals or be strictly specific in respect of only one metal. Special attention would be paid to the cell wall which structure determines sorption proceeding mechanisms. Problems of mechanisms of heavy metal biosorption by microorganisms at molecular level are discussed. The review also deals with the newest developments on improving the biosorption processes in microorganisms, yeast in particular.

[Taxonomy, ecology, and physiological and biochemical characteristics of industrially important microorganisms]

The work is dedicated to the investigations which were carried out in the Department of Physiology of Industrial Microorganisms in the recent years. Fundamental results of investigations dedicated to development of systematics of nocardio- and coryne-like bacteria, lactic acid bacteria and yeast; to the study of their distribution in nature, physiological-and-biochemical peculiarities. Considerable attention is paid to growth physiology of lactic acid bacteria and yeast, to lectin-forming microorganisms, to the study of fungi shaping under deep cultivation, as well as to microorganisms, taking part in the environment purification from heavy metals and oil products. Drugs created for treatment and prophylaxis of cattle diseases, for fodder siloing; new lactic acid preparations of functional direction, technological bases of sewage treatment for oil products and heavy metals are described.

[Lectin activity of antitumor substances synthesized by Bacillus subtilis B-7025]

Nutrient medium, which is optimal for synthesis of biologically active substances and allows obtaining stable outflow of Bacillus subtilis B-7025 to the culture medium, has been selected under the conditions of the bacillus periodic cultivation. It has been established that these substances are extracellular lectins with high activity and carbohydrate specificity to fructose-1.6-di phosphate, N-acetylneuraminic acid and glucose derivatives: D-glucuronic acid and D-glucosamine.

[Probiotics based on live cultures of microorganisms]

The modern state of probiotic design and production was discussed in the survey. The worldwide data concerning types of probiotics and their use for restoration of resident microflora of hot-blooded animals and people were systematized. Much attention has been recently paid to the use of the natural preparations to maintain and regenerate the state of the resident microflora of animals and people. These preparations are known as probiotics. The term "probiotic" means microorganisms or substances which are capable to render sanitary effect on macroorganism. I. I. Mechnikov's concept on detoxifications of harmful substances formed in the digestive tract of men by probiotics is expounded. The modern concepts of the probiotics division into groups have been presented. Different kinds of industrial probiotics were considered. The mechanism of positive action of probiotics and their mutual relations with micro- and macroorganisms were provided. The scientific substantiation of new probiotic design was presented.

[Search for lectin producers among the yeast of Pichia Hansen emend. Kurtzman genus]

Strains (103) of yeast from Pichia genus: P. anomala, P. guilliermondii and P. membranaefaciens species have been investigated. The researchers have found 87 strains (84.5%) capable to form extracellular and surface lectins with activity to 512 hemagglutinating units. The overwhelming number of strains (75.7-92.6%) synthesized lectins of the both forms. Considerably less quantity of lectin producers of some form--extracellular or surface ones--have been found. Availability of producers of extracellular lectins was characteristic to greater extent of the yeast of P. anomala and P. guilliermondii, and producers of surface lectins--mainly of P. guilliermondii. The most active producers of lectins have been isolated from human and animal organisms, soils and wine.

[On the identity of Candida utilis and Pichia jadinii yeast species]

Life cycles of Candida utilis (Henneberg) Lodder et Kreger-van Rij imperfect yeast (13 strains) used in industry were the study subject. When the strains were mated, we detected one of the stages of sexual process--conjugation of cells of the opposite mating type. Most of the studied cultures conjugated on the 2d-3d day. No ascospores were formed. Haploidy and heterothallism of the studied C. utilis strains were confirmed by hybridization of auxotrophic mutants. Based on PCR assay results, the yeasts are demonstrated to belong to the ascospore perfect yeast species of Pichia jadinii (A. et R. Sartory. We ill et Meyer, Wickerham) Kurtzman.

[Search for lectin producers among some yeast species]

Hemagglutinating properties of culture liquid and cells of 142 yeast strains of species Saccharomyces cerevisiae, Kluyveromyces marxianus, K. dobzhanskii, K. lactis var. lactis and K. lactis var. drosophilarum, isolated from various sources have been studied. A capacity of yeast (44% of the studied strains) to synthesize both lectins bound to a cell and extracellular lectins has been established; the latter have been found in yeast for the first time.

[Biological deacidification of wines using lactic-acid bacteria and yeasts]

Based on a study of 200 lactic-acid bacteria monocultures and 30 associating lactic bacteria and yeasts cultures, a stable association was created formed by Leuconostoc oenos, Pediococcus pentosaceus and Saccharomyces cerevisiae yeasts, intended for the biological deacidification of wine. Physiology of microorganisms and their effect on the wine chemical composition was studied. By means of selective association, high quality fine wines were produced from the high-acid wines.

[Optimization of the process of culturing yeast in the presence of the dispersed mineral palygorskite]

A positive effect from introduction of the highly dispersed mineral palygorskite in the nutrient medium for aerobic batch cultivation of the yeast Saccharomyces cerevisiae, the Kyivsky strain, used in production of champagne has been established experimentally. An adequate mathematical model describing the process of growth has been constructed. Optimal cultivation conditions have been determined which provided for the achievement of such yeast cell concentration in the culture fluid as 116 mln/ml, palygorskite concentration in the nutrient medium being 0.37 g/l and sucrose 2.0 +/- 0.2%. The yeast obtained possess higher fermentation activity.

[Use of PCR for the identification of representatives of Lactobacillus and Streptococcus]

REP- and ERIC-PCR genome analysis of lactic acid bacteria of genera Lactobacillus and Streptococcus have shown the presence of REP- and ERIC-repetitive sequences with high degree of homology. Amplification products which separation in agar gel results in formation of a specific fingerprint are obtained under REP- and ERIC-PCR. It is shown that REP- and ERIC-specific primers can be used for PCR identification of both enterobacteria and lactic acid bacteria isolated from different ecological niches.

[Certain features of culturing Saccharomyces cerevisiae (Kiev strain) in a wine medium]

The growth of yeast Saccharomyces cerevisiae Kyivsky strain, used in production of champagne, has been studied as affected by a number of factors. The optimum values of saccharose concentration and partial pressure of oxygen dissolved in the medium under which the carbohydrate source use efficiency achieved 9 mln cells/mg of saccharose have been established. The strain growth on the nutrient medium with 2% of saccharose traditionally used in the champagne production has been investigated under the conditions of periodic cultivation. It has been shown that at the beginning of cultivation the low values of the economic coefficient were determined by the Crabtree effect. The saccharose concentration in the culture liquid being decreased to 1%, the carbohydrate utilization efficiency decreases considerably. A chemostatic method of the strain cultivation under growth limitation has been proposed to achieve high concentrations of yeast. Under periodical cultivation the saccharose concentration in the culture liquid would be supported at the level of 0.5-1.0% by its fractional introduction to the fermenter.

[The taxonomic position, ecological aspects and physiological-biochemical characteristics of microorganisms having industrial importance]

The paper presents fundamental results of the investigations obtained in the Department of Physiology of Industrial Microorganisms at the Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine for the recent 15-20 years, as well as the Department developments directed to creation of biotechnological preparations, products and processes, most of which have been put into practice of the national economy and health protection. Data have been presented concerning the study of systematics, biology and ecology of nocardioform and coryneform bacteria, lactic acid bacteria and yeasts. When studying physiological-biochemical peculiarities and biological effect of the studied microorganisms, considerable attention has been paid to growth physiology of lactic acid bacteria, yeasts, lectin-forming bacteria, to processes of shaping of fungal mycelium under the conditions of batch cultivation as well as to microorganisms which take part in sewage treatment for heavy metals and oil products. The work also deals with the problems of creation and application in the economy of preparations intended for treatment and prophylaxis of gastro-intestinal diseases of cattle, poultry and swine, for siloing fodder, of new lactic acid preparations of functional direction, technological grounds of sewage treatment for oil products and six-valent toxic chrome.

[The antagonistic properties of bacteria isolated from the digestive tract of female mink housed in the area of the Chernobyl Atomic Electric Power Station]

Differences in species composition, number and level of antagonistic activity of bacteria isolated from the digestive tract of Chernobyl female minks of various age and with different immunological state have been established. Prevalence of anaerobes (bifidobacteria) and microaerophils (lactic acid bacteria) with the increase of microorganisms concentration along the channel: stomach, small and large intestine (10(7)-10(10)/g) was found in all the departments of digestive tract of minks. Among the identified lactic-acid bacteria Lactobacillus helveticus (10(7)-10(8)/g) prevailed in the stomach of the studied female minks, L. coryniformis (10(9)-10(10)/g) in the small intestine, L. casei (10(10)/g) in the large one. Antagonistic activity was most expressed in the strains of L. helveticus and L. casei, isolated from the younger (1.5 year-old) minks. Enterococcus faecalis isolated from the stomach of 1.5 year-old female minks was distinguished by the greatest antagonistic activity among identified enterococci. Strains of E. faecium isolated from the thin intestine of the young female minks (1.5 year-old) and from the large intestine of more nature animals (2.5 years) who received thymogen were characterized by the most expressed antibiosis among enterococci isolated bacteria a conclusion was made that the mechanisms of inhibitory effect of the studied microorganisms are underlied by not only their capacity to form organic acids but also by the capacity to produce antibiotic products.

[The use of the polymerase chain reaction method for the identification of representatives of the genus Enterococcus]

The possibility of the use of repetitive extragenic palindrome (REP)-specific primers to PCR-fingerprint analysis of Enterococcus genomes has been shown for the first time. Presence of the similar PCR products, and first of all the fragment 950 bp in size, has been observed in all the strains studied. Differences in PCR-product composition displayed genetical heterogeneity between Enterococcus faecium strains. These data evidence for the wide distribution of the REP, and rather high level of homology of the REP sequences among enterobacterial genomes.

[The antagonistic properties of microaerophilic bacteria isolated from the human and mink digestive tracts]

Study of antagonistic properties of microaerophilic bacteria isolated from human and mink gastroenteric tract have helped to establish differences in species composition, quantity and level of antagonistic activity of the studied microorganisms in respect to pathogenic microflora. It is shown that lactic acid bacteria identified as Lactobacillus fermentum and L. reuteri prevail among the strains isolated from the stomach and thin intestine of minks kept in the 30-km zone of Chernobyl NPP. Species composition of microaerophilic bacteria isolated from the digestive tract of the control minks is more variable. Antagonistically active bifidobacteria prevail in large intestine of experimental and control animals. Strains of lactic acid bacteria with the expressed antagonistic activity belonging to L. bavaricus, L. reuteri, L. coryniformis and L. maltaromicus have been found parallel with such known producers of antibiotic-like substances as L. fermentum. L. acidophilum. Streptococcus faecalis and bifidobacteria. L. maltaromicus most frequently occurred among antagonistically active strains revealed in feces of people which stayed in the zone of liquidation of the Chernobyl accident. Microaerophilic strains of bacteria (lactic acid, bifidobacteria and enterococci) manifest the expressed antagonistic activity connected with the capacity to not only acid formation but also to accumulation of antibiotic products of unknown nature. A strain of lactic acid bacteria L. fermentum 91 has been isolated from the contents of human gastroenteric tract. These bacteria are distinguished by most expressed and stable antagonism and characterized by the lack of pathogenicity in respect of albino mice that may be used to raise the microorganism resistance to gastric diseases.

[Yeasts contaminating salmon roe]

Quantitative and species compositions of yeast contaminating eggs, fry and fingerlings of Salmo gairdneri Rich under artificial breeding have been studied. Prevalence of species of genera Candida, Rhodotorula, Cryptococcus and Debaryomyces is noted. Yeast isolated from perished eggs and sick fry do not possess pathogenic properties. Certain strains of yeast make stimulating effect on the studied microorganisms.

[A microflora study of the gastrointestinal tract of mink housed within and outside of the area of the Chernobyl Atomic Electric Power Station]

Quantitative differences in the content of lactic acid bacteria isolated from the content of the stomach, small and large intestine have been established when studying microflora of the gastrointestinal tract of minks kept in the 30-kilometer zone of the Chernobyl NPP (experimental animals) and at the Cherkassy fur farm (control animals). Obligate heterofermentative species of lactic acid bacteria related to Lactobacillus fermentum and L. reuteri prevailed in the stomach of experimental minks. Species composition of lactic acid bacteria isolated from the stomach of the Cherkassy minks is characterized by the availability of both obligate and facultative heterofermentative species of bacteria--L. bavaricus, L. coryniformis, L. reuteri and of obligate homofermentative bacteria--L. salivarius and L. jensenii. In limiting dilutions (10(-9)-10(-10)) of the content of small intestine of the control minks one could find bacteria of L. coryniformis species and representatives of obligate heterofermentative bacteria--L. confusus and L. fermentum that is 1-2 orders higher then in the experimental minks. Both lactic acid bacteria and bifidobacteria (the latter up to 10(+9) cells/g of the content) were isolated from the lower departments of small and large intestine of the Chernobyl and Cherkassy minks. Among the species of lactic acid bacteria isolated from the experimental animals homofermentative species (L. acidophilus, L. sharpeae) and, heterofermentative (L. confusus, L. fermentum) in the control were found.(ABSTRACT TRUNCATED AT 250 WORDS)

[The growth characteristics of the yeast Saccharomyces cerevisiae on media containing ethanol and saccharose]

Joint effect of various concentrations of alcohol and saccharose in the medium as well as the influence of temperature are studied under conditions of batch cultivation of Saccharomyces cerevisiae. It has been found that saccharose added to the medium in the amount exceeding 1% is assimilated less efficiently. So, it is not expedient to exceed the above concentration in industrial nutrient media with 10-12 vol. % of ethanol. The biomass yield within 18-22 degrees C depends only on the alcohol amount in the medium. A further rise in temperature to 35 degrees C induces its inhibitory effect ever growing with the ethanol concentration in the medium. Mathematical modeling shows basic regularities of the growth process which permit predicting behaviour of the culture in the studied factorial space. Optimal values of saccharose concentrations and cultivation temperature for the most efficient cultivation of yeast on the ethanol-containing medium are determined.

[The growth characteristics of Enterococcus faecium under batch cultivation conditions]

Growth peculiarities of the strain of homoenzymic lactic acid bacteria Enterococcus faecium under periodic cultivation have been studied. The effect of carbohydrates source on the level of biomass accumulation and efficiency of its use by the strain is shown. Glucose concentration in the medium being increased from 1.0 to 3.5%, the economic effect decreases from 16.0 to 10.6%. It is established that only at the beginning of cultivation the specific growth rate of the strain is determined by the concentration of lactic acid. This dependence can be described by Ierusalimsky's equation. The obtained values of micronm and Kp are 1.5 h(-1) and 6.5 g/l, respectively. Biomass concentration being above 0.3 g ACB/l, the strain growth depends on two factors: inhibition of lactic acid and limitation of the sources of nitrogen nutrition. Interaction of these two factors results in considerable decrease of specific rate of bacterial growth.

[The effect of the cultivation conditions on lectin production by representative bacteria in the genus Bacillus]

Dynamics of the lectin activity accumulation in the culture liquid was studied through the example of certain representatives of spore-forming aerobic bacteria in the process of their growth. The environmental factors (the temperature, pH value, the presence of definite carbohydrates in the medium) were investigated for their effect on the biosynthesis of extracellular lectins by producers. Based on these studies it was possible to establish optimal conditions of cultivation and to obtain the high specific lectin activity of the culture liquid for each strain.

[The effect of the method of inoculation on the growth and variability of Bacillus thuringiensis H14 266/2-1]

The method of inoculation was studied for its effect on the growth and variability of Bacillus thuringiensis H14 266/2-1 when cultivating them in the liquid nutrient medium inoculate with inoculum prepared by different procedures. Optimal conditions of the inoculum preparation are determined. Productivity of the strain when inoculating the medium with the aerial-dry inoculum was studied as compared to the inoculation by the inoculum taken from the mown agar. It is established that selection of the virulent R-form from colonies should serve as a basis for the preparation of the stable morphologically uniform inoculum. The aerial-dried culture of bacilli is shown to be more effective since it is characterized by higher and stable indices of productivity and is more prepared to a long-duration storage than the inoculated agar media. A more rapid transition (by 2-4h) of the culture to the use of the carbon source is marked. The culture of bacilli is different in a higher developmental level: sporulation and crystallization initiate during the first hours of inoculation and by the 24th hour sporulation reaches 100% with the prevailing content of R-form.

[Use of starch-containing media for cultivation of Bacillus mesentericus]

When cultivating Bacillus mesentericus to produce proteinases it is advisable to use more available and cheap carbon sources--native maize meal or potato starch--instead of maltose; the products of their complete hydrolysis inhibit the biosynthesis of enzymes.

[Effect of the pH of the medium on the growth and chemical composition of the methanol-assimilating yeast Candida boidinii]

The yeast Candida boidinii T2A was grown in a medium with methanol or glucose as a sole source of carbon and energy, and the effect of the pH of the medium on the specific growth rate, the economic coefficient and the chemical composition of the yeast was investigated in a continuous chemostat process. The graphic presentation of the specific growth rate as a function of the pH is bell-shaped and, for all practical purposes, symmetric with respect to the ordinate of the optimal pH value. The maximal, specific rate of the yeast growth is 0.24 h-1 in the case of methanol and 0.38 h-1 in the case of glucose. The maximum in the curve is observed at pH 4.0 to 5.0. The yeast grows within a wide range of pH without a change in the economic coefficient. At all the studied dilution rates for a continuous culture exceeding 0.06 h-1 and the pH from 2 to 8, the yield of yeast biomass remains almost at the same level (36-40%). The results show a change in the chemical composition of the biomass depending on the pH of the medium and the rate of the yeast growth.

[Effect of the cultivation temperature on the growth and chemical composition of the methanol-assimilating yeast Candida boidinii]

The yeast Candida boidinii T2A was cultivated in a medium containing methanol or glucose as a sole carbon and energy source, and the effect of the cultivation temperature on the specific growth rate, the economic coefficient and the chemical composition of the yeast was studied in a continuous chemostat process. The specific rates of the yeast growth increase with the cultivation temperature up to optimal limits and then lower down abruptly in the supraoptimal zone. The maximal specific rate of the yeast growth in a medium with methanol at 30 degrees C is 0.24 h-1, while in a medium with glucose a 32 degrees C, it equals 0.38 h-1. In the suboptimal zone, the economic coefficient of the yeast growing in a medium with methanol at a dilution rate above 0.06 h-1 remains, for all practical purposes, at the same level (38-41%), while supraoptimal temperatures decrease the economic coefficient of the yeast. The results show a change in the content of protein and RNA as a function of the cultivation temperature and the dilution rate. It is concluded that the macromolecular composition of the yeast biomass is determined not only be the dilution rate, but also depends of temperature which regulates the rate of the yeast growth.