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L P Koval'chuk

Publications and source records attributed to L P Koval'chuk.

9 recordsLinked to original sources
PubMedDate not supplied

[Biological effect of lipid fractions of Actinomycetes].

Biological activity of lipid fractions of actinomycetes was examined on microorganisms and laboratory animals. The anabolic effect of the acetone fraction of Actinomyces aurigineus 2377 (on Wistar female rats), anabolic effect of sterols of Actinomyces griseus 15 (on chicks), and the high growth stimulating effect (up to 40-60%) of sterols of Actinomyces canosus 89 (on rats) were noted. The estrogenic effect of sterols of Act. griseus 15, Act. griseus 20 and Act. albodenitrificans 13a on the sex system was shown. The antimicrobial properties of lipid fractions differed in their selectivity with respect to the test organisms and depended also on the actinomycete species and cultivation conditions.

Actinomyces↗
PubMedDate not supplied

[Fatty acids of actinomycete phospholipids].

The fatty acid composition of phospholipids was studied in different actinomycetes growing in two media in order to detect their biological activity. The total phospholipids of the actinomycetes did not differ qualitatively and their composition was represented by the same series of fatty acids (C13--C19). The qualitative composition and the quantitative content of fatty acids in phospholipids depended on the composition of the growth medium. When the actinomycetes were cultivated in a complex medium, the proportion between fatty acids (C14:0, C14:1, C16:0, C17:0, C17:1, C18:1, C18:2) changed. The qualitative composition of fatty acids in phospholipids varied among the cultures. However, the content of palmitoleic, palmitic and oleic acids was elevated in all of the cultures. Under the given experimental conditions, the actinomycetes were found to synthesize phospholipids containing fatty acids with a high degree of unsaturation (mainly at the account of C16:1 and C18:1 acids).

Chemical Phenomena↗
PubMedDate not supplied

[Influence of the nutrient medium on the total lipid fatty acid composition of Actinomyces canosus].

GLC was used to study the composition of endocellular fatty acids of Actinomyces canosus 89 grown on a chemically defined medium and on a complex medium to which various components were added. Total lipids of the culture contain saturated and unsaturated fatty acids, from C13 to C18, with one or two double bonds. Addition of components to the medium stimulated the biosynthesis of myristic, stearic, oleic, and linoleic fatty acids. Changes in the composition of the growth medium modify the ratio between saturated and unsaturated fatty acids of total lipids, increasing the content of unsaturated fatty acids due to a higher rate of synthesis of linoleic and oleic fatty acids. An increase in the content of unsaturated fatty acids is a positive factor because these acids are involved in important physiological functions of both this organism and other living organisms.

Chemical Phenomena↗
PubMedDate not supplied

[Amino acid composition of Actinomyces mycelium].

The mycelium of actinomycetes cultivated on different media contained 15-16 amino acids of an identical qualitative composition. The percentage of amino acids depended on the composition of a growth medium. Under conditions of our experiments, a chemically defined medium was most favourable for the synthesis of the following amino acids: alanine, hystidine, glutamic acid, leucine, and valine.

Actinomyces↗
PubMedDate not supplied

[The fatty acid composition of total lipids and triglycerides in several actinomycetes].

Saturated and unsaturated fatty acids (C13-C18) have been found in the composition of lipids and triglycerides of actinomycetes by GLC. Qualitative composition of fatty acids was identical on chemically defined and organic media. Synthesis of unsaturated fatty acids by the actinomycetes was intensive (total yield over 50% and even 84.2% in Act. canosus) on the organic medium I which may be recommended for production of lipid fractions with elevated content of unsaturated fatty acids.

Actinomycetales↗