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The optimal methods for the extraction of exopolymeric complex (EPS) of Stenotrophomonas maltophilia 22M was determined. That EPS was synthesized in plankton and biofilm growth mode on the mild steel surface. It is desirable to use different physical and chemical methods for studying the EPS composition (carbohydrates and proteins) depending on the bacteria growth mode. In this way the interaction with ion exchange resin was the most effective for plankton growth mode to determine the maximum amount of carbohydrates (9.5 microg/ml), and the impact of heating to determine protein (3.9 microg/ml). For EPS biofilm in order to obtain maximum amount of carbohydrate it is desirable to use heating (30 microg/ml) and centrifugation (35 microg/ml). It is recommended to determine protein in the biofilm EPS after treatment with heating (3.75 microg/ml) and centrifugation (3.75 microg/ml).

The antioxidant properties of exine polymer matrix which forms the outer layer of pollen grain wall were studied. The main component of this matrix is sporopollenin - a unique biopolymer resistant to mechanical and chemical damage. The samples of isolated exine, purified from soluble compounds, were studied with EPR using stable nitroxyl radical TEMPO and DMPO spin trap. At the same time, we analyzed changes in fluorescence of DCFH which detected ROS in the solution. It has been established that exine effectively reduces TEMPO radical and eliminates hydroxyl radical. Also, the fluorometric analysis demonstrated that the exine eliminated H2O2, and this ability significantly decreased after treatment of exine with feruloyl esterase or mild alkaline hydrolysis (1M NaOH), i.e. after hydrolysis of hydroxycinnamic acid esters. After harsh hydrolysis (4M NaOH, 170 degrees C) of ethers bonds a large amount of hydroxycinnamic acids has been released, and exines have lost their antioxidant capacity almost completely. The obtained results point to the ability of extracellular polymer matrix of the exine to eliminate free radicals and H2O2 during crucial periods of male gametophyte development. The participation of ferulic acid and, possibly, of other hydroxycinnamic acids of sporopollenin in these processes has been demonstrated.

X-ray structure analysis, IR spectrometry, differential thermal analysis, and viscosimetry have been used to investigate the properties of novel five-component polyhydroxyalkanoates formed by short- and medium-chain-length monomers synthesized by the bacterium Wautersia eutropha B5786. As the molar fraction of hydroxyhexanoate contained in polyhydroxyalkanoates samples increased from 2.5 to 18.0 mol%, their degree of crystallinity decreased from 72 to 57%. The melting temperature of multicomponent polyhydroxyalkanoates (Tm) and their temperature for the onset of decomposition (Td) are lower than those of polyhydroxybutyrate, whose Tm is 168-170 degrees C and Td 260-265 degrees C. In multicomponent polymers (PHA(SC+MC)), both parameters decrease as the molar fraction of hydroxyhexanoate grows to 156 and 252 degrees C, respectively, in the range of hydroxyhexanoate content studied. Hydroxyhexanoate influences the physicochemical properties of polyhydroxyalkanoates similarly to hydroxyvalerate; as the fraction of either of these medium-chain-length monomers in polyhydroxyalkanoates increases, the crystallinity of the polymer decreases, but its thermostability remains unchanged.

Composite fluoropolymer-containing sorbents based on porous silicas were synthesized for the isolation and purification of biopolymers under nondenaturing conditions. Examples of the application of these sorbents in the separation of various mixtures of peptides and proteins and purification of nucleic acids from various sources (plasmid DNA and DNA from nucleated human blood cells) using the cartridge, column, and batch (sorption in a stirred volume) methods are presented. It was shown that the sorbents can be used in laboratory practice because they are selective to nucleic acids (DNA and RNA) and proteins. These materials combine the mechanical properties of the inorganic matrix with the specific sorption properties of the polymer phase and exhibit enhanced stability to alkaline hydrolysis. Alternative methods of preparing sorbents containing polytetrafluoroethylene, polytrifluorostyrene, and polyfluorobutadiene are described. By the example of polyfluorobutadiene-containing sorbents, a completely new method for obtaining fluorinated polymer phases was developed: the polymer phase was preliminarily formed on the surface of porous disperse carriers and was fluorinated with xenon difluoride.

Teichoic acids from the cell walls of marine bacilli Bacillus subtilis CMM (Collection of Marine Microorganisms) 234 (R-1) and B. licheniformis CMM 454 (1-1G-2) were isolated and characterized. These teichoic acids were found to have identical structures and are composed of the glucose, ribitol, and phosphoric acid residues. On the basis of 13C NMR and 31P NMR spectra of the teichoic acids and the products of their dephosphorylation, we established the following structure for the biopolymer: poly[-->5)-4-O-beta-D-glucopyranosylribitol-(1-phospho].

Pseudomonas species S-27 was grown on various substrates. It was established that the Pseudomonas species S-27 strain can produce biosurfactants of ramnolipid nature decreasing the surface and interfacial tension to 29.2 and 0.05 mN/m. respectively, as well as a biopolymer stabilizing the emulsions with hydrocarbons and oils. The biosurfactant and bioemulsifier synthesis is shown to depend of the substrate nature.

The work is devoted to the modern theory of gel electrophoresis in stationary and alternating electric fields, and it brings together results of numerous theoretical and experimental studies hitherto conducted. Main attention is drawn to the approximation definitions used in theory and to cases of divergences between theory and experimentation. Basic methods of gel electrophoresis and electrotransfer are principally analysed that appeared not long ago and showed to be greatly perspective. The resolution ability, advantages and disadvantages of pulsed methods are analysed, methods and instrumentation used in laboratory practice are described. Quantitative assessment of most important dependencies of applied significance are shown.