Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


The Influence of Culture Conditions on Production of Exopolysaccharide of Streptococcus Thermophilus

Isolated exopolysaccharide Streptococcus thermophilus. The conditions for the cultivation of bacteria for the maximum yield of the exopolysaccharide were selected. The bacterial culture of S. thermophilus was incubated for 48 hours in a liquid nutrient medium A. Welman at 38 °C, 180 rpm. on a thermostated shaker-incubator. As a source of carbon were used: sucrose, lactose and glucose. For the production of exopolysaccharide, the best source of carbon was sucrose. Isolation of the exopolysaccharide was carried out according to the J. Cerning method in our modification.

Characterization Surface Glycopolymers from Halophilic Gram-Negative Bacteria Chromohalobacter salexigens 1QL3 and Halomonas ventosae S5(2)

Extracellular and membrane polysaccharides of halophilic bacteria arouse the interest of researchers as promising biopolymers involved in adaptation and maintenance of normal physiology of microorganisms in saline environments that accompany many biotechnological processes. This work aimed at structural characteristic of surface glycopolymers of halophilic Gram-negative bacteria isolated from the salt samples of the lakes Qarun (Egypt) and Elton (Russia) – strains Chromohalobacter salexigens EG1QL3 and Halomonas ventosae RU5S2EL, respectively.

Preparation and Identification of the Molecular Properties of Alginate Synthesized by the Cultivation of Azotobacter vinelandii D-05

It is known that bacterial alginates are widely used in biomedicine as carriers in the immobilization of cells, enzymes and drugs. Their functional properties depend on their monomeric composition and molecular weight and vary depending on the source and the cultivation conditions. It was established that molasses (waste of sugar beet production) can be used as an effective and cheap source of nutrition for the growth of the bacterium Azotobacter vinelandii strain D-05 and the production of alginate.