Selenium Nanocomposites Having Polysaccharid Matrices Stimulate Growth of Potato Plants in Vitro Infected with Ring Rot Pathogen.

The influence of nanocomposites (NC) of selenium in matrices of arabinogalactan (Se/AG) and starch (Se/St) on in vitro vegetation of potato plants, peroxidase activity, and reactive oxygen species has been thoroughly studied. It has been shown that these nanocomposites of selenium have antimicrobial effect to the phytopathogenic bacterium Clavibacter michiganensis ssp. sepedonicus (Cms). In the present investigation, it has been shown that Se/AG NC (6.4% of Se) and Se/St NC (12.0% of Se) have no negative impact on the potato plants healthy and Cms infected, while stimulating their growth, number of leaves and weight of the vegetative part. Se/AG NC has shown a positive effect on potato plants by increasing its immune status by increasing the ROS content and increasing the peroxidase activity. With the use of the element analysis technique, it has been shown that scrutinized nanocomposites are not accumulated in potato plants after the bactericidal processing with the nanocomposites. Se/AG NC and Se/St NC as potential agents used for treatment of potato plants against pathogenic bacteria.

Silver-Containing Humic Substance-Based Nanocomposites-Agents for Healing of Potatoes from the Ring Rot.

The influence of silver-containing humic substance (HS)-based nanocomposites (NCs) obtained from mud, shale, and coals of three kinds of deposits in Mongolia on the viability and ability to biofilm formation of a phytopathogenic gram-positive bacterium Clavibacter michiganensis subsp. sepedonicus (Cms), as well as peroxidase activity and potato plant growth in vitro, has been investigated. The maximum reduction of the viability of bacterial cells was found in the case of incubation with HS-mu/Ag NC and HS-coal/Ag NC. It was found that HSs, including HS-mu and HS-sl, and NCs synthesized on the base of these HSs, HS-mud/Ag NC and HS-sl/Ag NC reduce more than twofold the activity of peroxidase in potato tissues. It was also found that HS-co and HS-coal/Ag NC stimulate the potato peroxidase activity, as well as biofilm formation of Cms bacterium. No negative effect of the studied NCs on the growth of potato has been revealed. Moreover, NC HS-mud/Ag based on mud had a stimulating effect on leaf formation in plants.

Effect of Metal-Containing Nanocomposites on Functional Status of the Thymus in Experimental Animals.

The effects of nanostructurized composites argentogalactomannan and argento-poly-1-vinyl-1,2,4-triasole on the kinetics of T cell maturation in the thymus of albino mice were studied. These nanocomposites stimulated the formation of CD3+CD4+CD8- and CD3+CD4-CD8+ cells from CD3-CD4-CD8- cells, the effect of argentogalactomannan was more potent. The efficiency of these compounds as agents improving the defense potential deserves special studies.

[Comparative study of immunomodulating effects of natural experimental preparations on phagocytosis of Yersinia pseudotuberculosis]. / Sravnitel'noe izuchenie immunokorregiruiushchikh svoistv éksperimental'nykh preparatov prirodnogo proiskhozhdeniia pri fagotsitoze Yersinia pseudotuberculosis.

To correct defects of the body's phagocytic system, the authors used experimental agents, such as vital activity products of plant cells, which were obtained by biotechnology. These included arabinogalactan, syringin, K-212, and DFEGP. The study agents activate the oxidative metabolism of macrophages, the production of active forms of oxygen, and thus enhance its bactericidal effect against Yersinia pseudotuberculosis. Syringin and arabinogalactan produce a more pronounced stimulating macrophageal effect in Yersinia pseudotuberculosis phagocytosis than do K-212 and DFEGP. The findings indicate that further studies of the effects of these tested and other agents on humoral and cellular immunity are required.

[Change in composition of structural components of leaf cellulose sulfate during fermentation bleaching by xylanases]. / Izmenenie sostava strukturnykh komponentov listvennoi sul'fatnoi tselliulozy v protsesse fermentativnogo otvelivaniia ksilanazami.

The possibility of the use of xylanase preparations for hydrolysing hemicelluloses in a non-bleached kraft pulp in order to facilitate its bleaching was studied. The effects of enzymatic preparations of the fungal and bacterial origins were examined, and the optimal conditions for xylanase activity were determined. UV spectroscopy demonstrated that the treatment of kraft pulp with the enzymatic preparations containing xylanase facilitated the subsequent removal of lignin and increased the brightness by 5%. The effect of enzymatic treatment was retained in the case of peroxide bleaching. The enzymatic preparations studied are promising for the development of chlorine-free pulp bleaching technologies.

[Change in composition of hydrolyzed lignin during composting]. / Izmenenie sostava gidroliznogo lignina v protsesse kompostirovaniia.

Microbial assemblages were composed for composting hydrolysed lignin. Data on bioconversion of aromatic compounds with various types of substitution in the ring were used for this purpose. Composting of hydrolysed lignin reduced the contents of lignin, low-hydrolyzable polysaccharides, resins, and low-molecular-weight phenols and resulted in accumulation of humic acids. The resulting compost showed no phytotoxicity.