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New water-soluble SeS2 containing nanocomposites are obtained via ion-exchange interaction between selenous acid and ammonium sulfide in water using natural arabinogalactan and starch polysaccharides as nanoparticle stabilizers. The transmission electron microscopy, X-ray diffraction analysis, and dynamic light scattering data show that nanocomposites are formed as spherical crystalline SeS2 nanoparticles 5–140 nm in size, dispersed in polysaccharide matrices. The type of stabilization matrix and ratio of reactants have a decisive influence on the nanomorphological properties of the materials obtained.

It has been previously shown that the chemically synthesized nanocomposite of selenium with arabinogalactan (NC Se/AG) is characterized by antibacterial effect upon the agent of ring rot – gram-positive bacterium Clavibacter sepedonicus (Cms), with the NC Se/AG having no negative effect on potato plants. In the present paper, it has been found that, 1 hour after the treatment of the NC Se/AG, a substantial elevation of lipid peroxidation products was observed in potato root tissues. This supports earlier results on the increase in reactive oxygen species (ROS) production in potato root tissues under the influence of NC Se/AG. It is proposed that the increased ROS content in potato may inhibit pathogen colonization of plants. This has been tested by seeding homogenised plant tissues of various potato zones (roots, stems, shoot apex zone) onto the nutrient medium. In plants infected with Cms and untreated with the NC, the number of colony forming units (CFUs) of Cms has been shown to be numerous both in potato culture medium and in root and stem tissues. In shoot apex zone of such plants, it has been revealed, bacteria also present, but in smaller quantities. Similar data have been obtained by seeding homogenised tissues from roots and stems of potato plants treated with the NC followed by infection with Cms. However, seeding from shoot apex zones of the plants has been given 4 times less CFUs than from potato plants not treated with the NC. The effect of the NC Se/AG upon the pathogen colonization of plants appears to depend on the titre of the microorganism. In shoot apex zone of plants, characterized with small number of CFUs of Cms, the pathogen growth has been decreased. For the first time, Cms bacteria in potato plant tissues in vitro have been visualized with the aid of scanning microscopy.

The growth-stimulating activity of three selenium nanocomposites (NCs) in various matrices based on arabinogalactan (NC Se/AG, 6.4% Se), starch (NC Se/St, 2% Se), and carrageenan (NC Se/Car, 12% Se) with respect to plants of radish, soybean, and potato was investigated. It was shown that the treatment of plant seeds with NCs stimulated root growth during germination. It was found that the studied NCs affected both the level of lipid peroxidation and the activity of the antioxidant enzyme glutathione peroxidase (GPX). The treatment of radish seeds with NCs stimulated root growth during their germination and reduced the content of diene conjugates (DC) in root tissues. It was shown that soaking seeds in NC Se/AG solution increased the GPX activity in the tissues of the radish root by 40%. Stimulation of soybean root growth under the influence of NC Se/Car may also be associated with the activation of GPX. Furthermore, in potato plants, this NC led to the stimulation of germination; however, this was probably due to the activation of other antioxidant enzymes. The results obtained allow us to consider Se NCs as potential plant growth stimulants.

Experiments on rat model of toxic liver damage (CCl4, subcutaneously) have demonstrated that selenium nanopreparation on arabinogalactan matrix and partially arabinogalactan alone prevented the development of oxidative stress assessed by the balance of LPO and antioxidant defense processes.

Carbonaceous (black) shales containing increased metallogenic potential [1, 2] are generated in definite geodynamic and paleogeographic conditions: predominantly in stagnant riftogenic sea basins where the sedimentary process is accompanied by a supply of products of volcanic and underwater hydrothermal activity [3]. The carbonaceous sedimentary and volcanogenic‐ sedimentary formations generated in such conditions possess all the necessary ore-genetic potentials (fluid‐ metallogenic and barrier‐geochemical). Metals are therewith often dispersed in the carbonaceous‐mineral rock groundmass and do not form separate mineral macroscopic phases. At definite stages of the postsedimentation transformation of carbon-containing sediments (diagenesis, katagenesis), biopolymers and geopolymers are generated in it. Under the increasing PT-conditions in the interior, these substances become a source of liquid and gaseous (and able to migrate) components of oils, and all at once to a significant degree inherit the metallogenic potential of the oil source carbonaceous rocks. This is confirmed by the discovery of deposits of oils and bitumoids enriched in metals in different regions of the world [4, 5]. Now there is significant evidence that the processes of oil and ore formation in black shale strata are closely connected [3, 4]. However, questions such as the types of bonds of metals with carbonaceous matter, ways of metals migration in carbonaceous media, and conditions of their concentration at different physico-chemical barriers with formation of ore deposits remain practically unsolved.

Effect of mechanochemical activation of mono-and mid-fraction of phosphorites from the Burenkhan deposit was studied by IR and ESR spectroscopies in vibration and planetary mills.

The immunomodulatory properties of perspective prebiotics--beta-galactose-containing--polysaccharides arabinogalactan, arabinogalactan with flavonoids, carrageenan, galaktomannan have been studied. It was established that oral administration of the studied beta-polysaccharides to experimental animals leads to a significant activation of immune cells and the synthesis of humoral factors in their organism which significantly increases the cytotoxic activity of blood serum. The most pronounced immunomodulatory effect exhibits arabinogalactan with flavonoids and carrageenan.

The formation and catalytic properties of hydrogenation catalysts based on palladium(II) complexes with primary phosphines were studied. With the use of IR and UV spectroscopy, XRD analysis and GLC, it was found that the interaction of bis(acetylacetonato)palladium(II) or palladium(II) acetate with primary phosphines in an inert atmosphere resulted in the formation of polynuclear palladium complex associates mainly containing μ3-PR and a coordinated phosphine. Polynuclear palladium complexes and the palladium phosphide Pd6P, which is formed from these complexes in an atmosphere of hydrogen, serve as supports for Pd(0) clusters. The effects of the ratio between initial components and the nature of the acido ligand at the palladium atom on the optimum conditions of catalyst formation were considered.