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A N Shkidchenko

Publications and source records attributed to A N Shkidchenko.

44 records · Page 3Linked to original sources
PubMedDate not supplied

[Simultaneous action of environmental factors on Candida utilis growth in a chemostat culture].

The effect of carbon dioxide and carbon-containing metabolites on the growth of Candida utilis was studied under the conditions of phosphate limitation. The limiting factor and the hydrocarbonate form of CO2 were shown to act simultaneously on the yeast growth, decreasing its rate. The threshold concentration of the limiting factor remained unchanged. Carbon-containing metabolites produced a similar action on the chemostat yeast culture. The factors limiting the rate of the yeast growth did not switch over.

Candida↗
PubMedDate not supplied

[Continuous cultivation of mono- and mixed cultures of yeasts growing in birch vernal sap flows].

All of the studied yeast organisms were characterized by a similar range of temperatures optimal for growth and by the ability to grow well at a relatively low content of a nitrogen source in the medium; however, their growth rates were different. The lowest growth rate was typical of the primary, further displace, yeast flora of spring sap flows. Both positive and negative types of interrelationship between yeast species were established during combined cultivation of yeasts. There is a principal correlation between the data obtained upon continuous cultivation of mixed cultures in the laboratory and the results of studies of the natural microbial cenosis; therefore, it is possible to reproduce the growth of the latter in experiments with a sufficiently high degree of approximation.

Cryptococcus↗
PubMedDate not supplied

[Chitinolytic activity of Actinomyces kurssanovii under periodic and flow cultivation].

Chitinolytic activity of Actinomyces kurssanovii cultivated on the medium containing highly purified crab chitine as carbon source was studied. Under periodic cultivation the first to be accumulated were the (CHI)--enzyme that degraded ground chitine and beta-N-acetylglucosaminidase (EC 3.2.1.30). Then by the 15--16th hour of the producer growth chitinase-poly-(1,4-beta-(2-acetamido-2-deoxy-D-glucoside)-glucanohydrolase (EC 3.2.1.14) and beta-N-acetylglucosaminidase splitting N-N-diacetyl chitobiase were intensively accumulated. It was demonstrated that a highly active chitinolytic preparation of Act. kurssanovii can be obtained under flow cultivation at a dilution coefficient of D = 0.03--0.12 hr-1. A correlation between the respiratory activity of the culture and components of the chitinase system was established.

Acetylglucosaminidase↗
PubMedDate not supplied

[Autoselection of Pichia pinus yeasts by 3-stage multiflow cultivation].

Three-stage multiflow cultivation of the yeast Pichia pinus, with the flow rates of 0.27, 0.6 and 1.2 hr-1, respectively, in the first, second and third fermenters, resulted in autoselection and the parent strain was substituted by a selective one in the third fermenter. The selective strain differed from the parent one by the size of cells, had a higher specific growth rate, and contained more protein. These properties of the selective strain were preserved in the course of one-stage cultivation.

Ascomycota↗
PubMedDate not supplied

[The effect of carbon dioxide gas on the growth of Candida utilis yeasts during continuous cultivation in a chemostat].

The cells of Candida utilis were cultivated in the conditions of chemostat, and the growth was limited by a nitrogen source. Accumulation in the medium of carbon dioxide inhibited the growth of the microbial population. The growth was now limited not by a source of nitrogen but by an excess of one of the forms of carbon dioxide--hydrocarbonate. This inhibition was reversible and could be eliminated either by intensifying ventilation of the apparatus or by varying pH of the medium within the range optimal for the growth, which changed the ratio between free and hydrocarbonate forms of carbon dioxide in the growth medium.

Bicarbonates↗