[Activity of endopolygalacturonase in culture fluid of experimentally prepared polyploid cultures of Saccharomyces vini]. / Aktivnost' éndopoligalakturonazy v kul'tural'noi zhidkosti éksperimental'no poluchennykh poliploidnykh kul'tur Saccharomyces vini.

The action of colchicine solutions on a diploid Saccharomyces vini culture used in viniculture yielded three polyploid strains. The strains differ from the parent culture in their cell morphology and a higher endopolygalacturonase activity.

[Mutagenic action of acenaphthene on haploid and diploid cultures of Candida scottii]. / Mutagennoe deistvie atsenaftena na gaploidnuiu i diploidnuiu kul'tury Candida scotii.

Acenaphthene used as vapour increases the frequency of morphological mutations as well as mutations yielding strains with a reduced activity of respiration in Candida scottii. The diploid culture has more mutants than the haploid culture. The frequency of mutants depends on the duration of acenaphthene action. Cells more resistant to the action of acenaphthene vapour are selected in the haploid culture when C. scottii cells are transferred many times into new wort drops. As a result, the frequency of mutations decreases. When the diploid culture is exposed to the action of acenaphthene vapour for a longer time, the frequency of mutations rises. Apparently, the diploid culture has a lower activity of reparation of premutational damages than the haploid culture and therefore the number of mutant cells increases.

[Effect of petroleum hydrocarbons on the viability of cyanobacteria in association with oil-oxidizing bacteria]. / Vliianie neftianykh uglevodorodov na zhiznesposobnost' tsianobakterii v assotsiatsii s nefteokisliaiushchimi bakteriiami.

An important aspect in the problem of interactions between microorganisms in the conditions of oil pollution is how to preserve the viability of phototrophic organisms if active oil-oxidizing microflora is present in the environment. As was illustrated using a closed model ecosystem, the association 'cyanobacteria--oil-oxidizing bacteria' is capable of withstanding the negative effect of oil pollution, but within the range of hydrocarbon concentrations which can be oxidized by oil-oxidizing bacteria during a very short time. The biological equilibrium in the ecosystem was maintained and the number of viable cells of the phototrophic component in the ecosystem increased if the oil-oxidizing bacteria started to function at the same time as toxic compounds commenced to produce their effect on the microorganisms.

[Effect of cyanobacteria excretions and cell biomass on hydrocarbon-oxidizing mycobacteria]. / Vliianie vydelenii i kletochnoi biomassy tsianobakterii na uglevodorodokisliaiushchie mikobakterii.

The presence of cyanobacterial cells and their exocellular excretions in an aqueous ecosystem stimulated biodegradation of diesel fuel. As was established using the technique of complete factor analysis, nitrogen addition to the medium and the presence of cyanobacterial cells in it are important for the growth of oil-oxidizing bacteria, while exocellular excretions of the cells are not sufficient for such a growth. The mycobacterial growth depended, to a certain extent, on the age of cyanobacterial cultures.