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1.
Cryobiology ; 29(3): 385-90, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1499323

RESUMO

Eighteen yeast strains were tested for their ability to survive the freeze-thaw process while being cryoprotected. Cryoprotection was accomplished by combining penetrating and nonpenetrating cryoagents. Four nonpenetrating (two extracellular polysaccharides of yeast and two extracellular glycoproteins of yeast) and two penetrating agents were used together with the nutritive-rich medium. Eight different mixtures were tested. The highest survival rate was obtained with glycoproteins of Rhodosporidium toruloides together with DMSO and nutritive-rich medium.


Assuntos
Crioprotetores/farmacologia , Glicoproteínas/farmacologia , Polissacarídeos/farmacologia , Aminoácidos/análise , Carboidratos/análise , Criopreservação/métodos , Crioprotetores/química , Dimetil Sulfóxido , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacologia , Glicoproteínas/química , Polissacarídeos/química , Leveduras
2.
Mycoses ; 34(7-8): 349-52, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1803241

RESUMO

Five strains of Malassezia pachydermatis isolated from small animals in Bratislava were subcultured, maintained under sterile paraffin oil and preserved in liquid nitrogen. Morphological and physiological characteristics as well as the analysis of long chain fatty acids of the cell mass were determined. The results showed that the maintenance in liquid nitrogen is the most satisfactory method of preservation of pure cultures of Malassezia pachydermatis.


Assuntos
Doenças do Gato/microbiologia , Doenças do Cão/microbiologia , Malassezia/crescimento & desenvolvimento , Pitiríase/veterinária , Preservação Biológica , Animais , Gatos , Cães , Malassezia/isolamento & purificação , Pitiríase/microbiologia
6.
Folia Microbiol (Praha) ; 32(5): 426-30, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3319843

RESUMO

Storage in liquid nitrogen of a collection of C. albicans, C. tropicalis and related species checked by numerical and classical taxonomy is described. Strains stored for 3 years in liquid nitrogen were thawed and their survival was tested. After adaptation and regeneration, their fermentation and assimilation spectra, production of chlamydospores and pseudomycelia, appearance and radial growth rate of giant colonies were investigated and compared with the properties of cultures stored under paraffin oil. It follows from the results obtained that two different media--with an increased content of a nitrogen source and with an increased carbon source content--should be used for the post-heating adaptation and regeneration of yeast cells. In some strains it is useful to store them at 4 degrees C for additional time intervals in order to increase survival of the cells. The above strains can be successfully stored in liquid nitrogen.


Assuntos
Candida albicans/citologia , Candida/citologia , Candida/isolamento & purificação , Candida albicans/isolamento & purificação , Congelamento , Humanos , Nitrogênio
7.
Folia Microbiol (Praha) ; 31(5): 367-74, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3792963

RESUMO

Different ways of the evaluation of viability of cultures stored in liquid nitrogen are compared. The streaking technique is recommended for a rapid evaluation. It is sufficient to determine the suitability of the medium, of cryopreservatives and of the whole procedure. On storage of melted cultures for 1-7 d at 4 degrees C it was found that the cultures could be transported directly in a suitable package maintaining the low temperature on the condition that the transportation would not last longer than 5 d.


Assuntos
Leveduras/crescimento & desenvolvimento , Congelamento , Nitrogênio , Fatores de Tempo
8.
Antonie Van Leeuwenhoek ; 49(6): 571-8, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6370131

RESUMO

Nineteen strains of yeasts possessing different characteristics were stored in liquid nitrogen and after 5 years phenotypic characters were evaluated and compared with equivalent strains preserved under paraffin oil. All qualitative characters tested remained stable, and quantitative characters varied only within the range of natural variability.


Assuntos
Congelamento , Técnicas Microbiológicas , Preservação Biológica , Leveduras/fisiologia , Nitrogênio , Óleos , Parafina
9.
Folia Microbiol (Praha) ; 27(4): 242-4, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7141326

RESUMO

Nineteen strains of taxonomically diverse yeast species tested survived freezing and subsequent five-year storage in liquid nitrogen at - 196 degrees C, using a medium M 2 composed of malt extract, yeast extract, peptone, calf serum and dimethyl sulfoxide. Viability of the yeast cultures after long-term storage ranged from 5 to 97% (average 62%) compared with the viability of the cultures prior to freezing. The use of liquid nitrogen refrigeration for preserving yeast cultures is strongly advocated.


Assuntos
Refrigeração , Leveduras/fisiologia , Nitrogênio
12.
Z Allg Mikrobiol ; 21(10): 739-42, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7199787

RESUMO

A new yeast, Torulopsis ethanolitolerans and its variety minor, both isolated from industrial sulphite fodder yeast cultivated on synthetic ethanol as the only source of carbon, originally designated R 5, R 6 and the variety R 7, are described. This species differs from all recently accepted Torulopsis species (resp., Candida species), which do not assimilate nitrate, not ferment any sugars, not produce urease, by the assimilation of maltose, but not of sucrose, lactose and D-xylose.


Assuntos
Candida/classificação , Candida/citologia , Candida/fisiologia , Metabolismo dos Carboidratos , Meios de Cultura , Esculina/metabolismo , Etanol/metabolismo , Lactatos/farmacologia , Ácido Láctico , Terminologia como Assunto
14.
Folia Microbiol (Praha) ; 25(4): 301-5, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6998838

RESUMO

The ability to degrade mannan in the yeast Saccharomyces cerevisiae, i.e. the ability to produce an enzyme of the alpha-mannosidase type was tested in 57 representatives of various genera and species of yeasts and yeast-like organisms. Their growth was simultaneously monitored on soluble mannan and on 4-nitrophenyl-alpha-D-mannopyradnoside. The majority of strains produced alpha-mannosidase (EC 3.2.1.24).


Assuntos
Mananas/metabolismo , Polissacarídeos/metabolismo , Leveduras/enzimologia , Manosidases/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Leveduras/metabolismo
15.
Z Allg Mikrobiol ; 20(9): 579-81, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7210708

RESUMO

A new yeast, Candida ethanolica, isolated from industrial fodder yeast cultivated on synthetic ethanol as the only source of carbon, originally designated III-5 and III-6, is described. This species differs from all recently accepted Candida species in not assimilating nitrate, not producing urease and not fermenting sugars.


Assuntos
Candida/classificação , Candida/citologia , Candida/fisiologia , Metabolismo dos Carboidratos
16.
Folia Microbiol (Praha) ; 25(1): 56-67, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7353807

RESUMO

Aureobasidium pullulans (de Bary) Arnaud was isolated from different natural materials plant blossoms in particular. Elements of vegetative multiplication, structure of colonies and cultures in liquid media were analyzed in detail, leading to construction of the life cycle of this organism. Morphological polymorphism was found to be combined with the production of melanin and the polysaccharide pullulan. Morphological analysis served for a directed selection for studies of physiological properties of this organism and its practical application.


Assuntos
Fungos Mitospóricos/citologia , Meios de Cultura , Melaninas/biossíntese , Fungos Mitospóricos/crescimento & desenvolvimento , Fungos Mitospóricos/metabolismo , Polissacarídeos/biossíntese , Esporos Fúngicos/citologia
17.
Folia Microbiol (Praha) ; 25(1): 68-73, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7353808

RESUMO

Seventy-seven properties of Aureobasidium pullulans including utilization of various carbon sources, decomposition of the lignin-cellulose complex and the respective enzymes were checked in the present communication. According to these properties the group of 43 strains was separated in three parts, out of which two groups were found to belong to varieties A. pullulans var. pullulans and A. pullulans var. melanigenum. The third group formed a marginal part. The two varieties differed in numerous biochemical markers, particularly in the absence of monophenol monooxygenase in the variety A. pullulans var. pullulans.


Assuntos
Fungos Mitospóricos/metabolismo , Metabolismo dos Carboidratos , Celulose/metabolismo , Lignina/metabolismo , Fungos Mitospóricos/classificação , Fungos Mitospóricos/enzimologia , Nitrogênio/metabolismo , Oxigenases/metabolismo , Especificidade da Espécie
18.
Folia Microbiol (Praha) ; 23(5): 353-61, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-308919

RESUMO

Of a total of 177 strains of yeasts and yeast-like organisms only 8 were capable of producing alpha-amylase; most strains were able to utilize 1,4-alpha-glucans by means of enzymes acting on the non-reducing ends of the outer glucan chains.


Assuntos
Amilases/biossíntese , Fungos/enzimologia , alfa-Amilases/biossíntese , Amilose/metabolismo , Fermentação , Fungos/metabolismo , Glucanos/metabolismo , Maltose/metabolismo , Especificidade da Espécie , Amido/metabolismo , Leveduras/enzimologia , Leveduras/metabolismo
19.
Antonie Van Leeuwenhoek ; 44(2): 229-41, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-582097

RESUMO

All 20 yeast strains of 17 species tested survived 75 days (the length of the experimental period) in liquid nitrogen at -196 C. The components of the more protective of the two freezing media used were (w/v) malt extract 2.5%, yeast extract 0.25%, peptone 0.5%, calf serum 15% (v/v) and dimethyl sulfoxide 10% (v/v). Viability of the cells in this medium after rapid uncontrolled freezing and thawing in selaed plastic ampoules ranged from 2% to 98% (average 67%) compared with the viability of the cultures before freezing. In only 4 strains was survival lower than 50%. (90 references).


Assuntos
Congelamento , Preservação Biológica , Leveduras/fisiologia , Meios de Cultura , Dimetil Sulfóxido/farmacologia , Especificidade da Espécie , Leveduras/efeitos dos fármacos , Leveduras/crescimento & desenvolvimento
20.
Folia Microbiol (Praha) ; 23(5): 366-71, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-700524

RESUMO

The ability to grow in liquid media with D-xylose, xylan from decidous trees, and hemicelluloses from conifers was tested in 95 strains of 35 genera of yeasts and yeast-like organisms. Of 54 strains thriving on xylose, only 13 (genera Aureobasidium, Cryptococcus and Trichosporon) utilized xylan and hemicelluloses as growth substrates. The árowth media of these strains were found to contain xylan-degrading enzymes splitting the substrate to xylose and a mixture of xylose oligosaccharides. The ability of these yeasts to utilize the wood components (hitherto unknown in the genus Crytococcus) makes them potential producers of microbial proteins from industrial wood wastes containing xylose oligosaccharides, xylan, and hemicelluloses as the major saccharide components without previous saccharification.


Assuntos
Celulose/metabolismo , Polissacarídeos/metabolismo , Xilanos/metabolismo , Xilose/metabolismo , Leveduras/metabolismo , Sistema Livre de Células , Solubilidade , Especificidade da Espécie , Xilosidases/metabolismo , Leveduras/crescimento & desenvolvimento
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