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S S Nagornaia

Publications and source records attributed to S S Nagornaia.

At least 19 recordsLinked to original sources
PubMedDate not supplied

[Screening of alpha-N-acetylgalactosaminidase producers among microorganisms of different taxonomic groups].

Screening of producers of alpha-N-acetylgalactosaminidase among 854 strains of micromycetes, 171 yeast and 357 bacterial cultures has been carried out. A capacity to synthesize the enzyme was revealed in 11% of cultures. Representatives of Aspergillus genus (activity--0.11-0.142 un./ml) were most active in producing the enzyme. It has been established that glucosidases spectrum in the culture liquid of 18 most active strains was characterized by complete homogeneity and by the presence of a rather high level (0.5-0.9 un./ml) of alpha-galactosidase activity. Complex preparations of alpha-N-acetylgalactosaminidase and alpha-galactosidase have been obtained from the culture liquid of producers by fractionation by ammonium sulphate (30 and 90% saturation); their pH- and thermo-optimum, pH- and thermal stability have been studied. It was shown possibility to induce alpha-N-acetylgalactosaminidase synthesis by a number of carbohydrates (galactose, glucose, galactosamine, and glucosamine), complex-forming substances (guanidine HCl), nitroaminoguanidin and guanidine carbonate and bovine blood. As a result the strain of Aspergillus niger 185 III was chosen which activity level could be increased more than 3 times (activity--0.6 un./ml as compared to initial one).

Animals↗
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[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.

Food Microbiology↗
PubMedDate not supplied

[Distribution of Rhodosporidium diobovatum yeasts in soil and on plants].

As was found by the hybridization technique, 43 strains among 92 studied strains of the yeast Rhodotorula glutinis belong to Rhodosporidium diobovatum Newell et Hunter (Ustilaginaceae, Basidiomycetes). The strains of Rhodosporidium diobovatum were found in oil-bearing soils, rhizosphere, and phyllosphere of cultivated and wild plants.

Basidiomycota↗
PubMedDate not supplied

[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.

Culture Media↗
PubMedDate not supplied

[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.

Candida↗
PubMedDate not supplied

[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.

Hemagglutination Tests↗
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[Yeast flora of plant rhizosphere and phyllosphere].

The species belonging to the genera Cryptococcus and Hansenula with saturnian spores predominate in the rhizosphere of agricultural plants. The sporiferous strains of Debaryomyces, Hanseniaspora apiculata, Metschnikowia pulcherrima, and asporogenic Candida krusei and Trichosporon cutaneum prevail in the rhizosphere of wild plants. Candida krusei and Trichosporon cutaneum prevail in the rhizosphere of wild plants. The cultures of Rhodotorula, Candida krusei and Metschnikowia pulcherrima are typical of the phyllosphere of both cultural and wild plants. The phyllosphere of cultural plants contains also the asporogenic strains of Cryptococcus, Candida tropicalis, Trichosporon pullulans, Tr. cutaneum, and Hansenula, while Hanseniaspora apiculata and Saccharomyces cerevisiae predominate in the phyllosphere of wild plants. The yeast flora of the majority of studied plants is diverse and comprises 10--20 species (in cabbage, potato, linden, aspen, and pear trees). The rhizophere and phyllosphere of some plants contain only 2 to 4 yeast species (onion, hop, wild apple).

Plants↗
PubMedDate not supplied

[The intestinal microflora of persons subjected to a radiation lesion].

The content of large intestine has been studied in persons exposed to radiation injury in consequence of the accident at the Chernobyl Atomic Power Plant. It is stated that bifidobacteria (10(7)-10(10) cells in 1 g of feces) prevailed (as in healthy people), Bifidobacterium indicum being a dominating species. Amount of lactic-acid bacteria in 1 g of defecations of examined patients was within the range of 10(6)-10(9) cells and in certain persons it reached 10(10) cells (primarily fecal Enterococci). A considerable amount of patients with acute radiation sickness of the 3d degree had in their intestine 10(9)/g of lactic-acid bacteria, Lactobacillus casei and L. plantarum prevailing there. The frequency of yeast isolation from defecations of patients constituted 83%, while the number of cells in 1 g of feces--from 10 to 10(4). Yeast of the Candida genus, mainly Candida parapsilosis, prevailed. The species composition of isolated microorganisms has no substantial differences from microcenosis of healthy people. The content of intestine of persons suffered from radiation is characterized only by greater amount of lactic-acid bacteria and enterococci as compared with healthy adults.

Accidents↗
PubMedDate not supplied

[The antibiotic properties of macrocyclic trichothecene mycotoxins].

Some trichotecenic mycotoxins (verrucarine A, roridines A and H, T-2-toxin) have been studied for their antibiotic effect on a wide spectrum of the yeast cultures (761 strains). The studied substances differ both in their activity and the action character. The yeast strains promising for development of microbiological methods of indication and detoxification of mycotoxins have been revealed.

Antifungal Agents↗
PubMedDate not supplied

[The effect of Pichia guilliermondii yeasts on the body of laboratory animals].

Conditionally pathogenic species Pichia guilliermondii which, being parenterally introduced to white mice, induced pathological changes in viscera and rarely death, has been revealed among species of genus Pichia previously considered as a nonpathogenic genus. The strains differ considerably between themselves in virulence. The latter does not depend on the yeast sex and the source of strain isolation.

Animals↗
PubMedDate not supplied

[Yeast antagonists in the normal microflora of the intestinal tract in the long-lived inhabitants of Abkhazia].

Yeast of different taxonomic groups isolated from the organism of long-livers of Abkhazia have been studied for their antagonistic activity relative to the conditionally pathogenic and pathogenic bacteria and for the presence of the killer factor. It is shown that representatives of ten species of fungi are antagonists of the studied bacteria, the strains of Saccharomyces cerevisiae being the most active antagonists. The presence of the killer factor is found in representatives of five species o the yeast. It is supposed that the antagonistic activity relative to the bacteria and the killer activity in the yeast are due to substances of different chemical nature.

Aged↗