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Optimal conditions were chosen for obtaining microcrystalline cellulose (MCC) by means of birch wood delignification by hydrogen peroxide in the presence of sulphuric catalyst for the purpose of obtaining MCC with low lignin and hemicellulose content. The evolution of MCC into porous carbon materials (PCM) during pyrolysis within temperature range 200-800 °C was studied by means of IR spectroscopy, XPA, DTA-DSC, XPES, SEM and elemental analysis. It was established that depending on the final pyrolysis temperature and heating rate, the yield and specific surface of solid pyrolysis products vary within the range 97.3-18.3 mass % and 1-473 m²/g, respectively. The most substantial loss of MCC mass is observed within pyrolysis temperature range 300-400 °С. An increase in heating rate during MCC pyrolysis causes a decrease in PCM yield and promotes the development of its porous structure. With pyrolysis temperature range of 400-500 °С, MCC undergoes only paprtial carbonization, while solid products are present in the form of carbon fibres and cellulose clews.

The use of natural oligosaccharides and polysaccharides as complexing agents for the delivery of pharmaceutical substances causes a substantial increase in their therapeutic activity and storage stability, and reduces side effects. The use of modern physical methods to study molecular processes allows obtaining unique information on the structure, dynamics and physicochemical properties of supramolecular inclusion complexes of pharmaceutical compounds. The review illustrates the possibilities of physical methods in studying the means of drug delivery in the solid state and in solutions, and in establishing the mechanisms of increasing bioavailability of pharmaceutical compounds within inclusion complexes.

Modified technology of obtaining arabinogalactan from wood of Larix sibirica and Larix gmelinii on the basis of aqueous extraction of arabinogalactan in the ultrasonic set-up, filtration of the extract, its separation into fractions by means of ultrasonic spraying and concentrating in a rotary vacuum evaporator is considered. The concentrate is precipitated in the organic solvent, washed, dried and ground. It is notable that arabinogalactan extraction is carried out without preliminary extraction of dihydroquercetin.

Intermolecular complexes of the guest-host type possessing increased water solubility were obtained by means of solid-phase mechanochemical treatment of a number of benzimidazole antihelminthic pharmaceutical substances with water-soluble polymers - polyvinylpyrrolidone, hydroxyethyl starch, arabinogalactan polysaccharide (from wood of Larix sibirica and Larix gmelinii ). Physicochemical studies of the complexes were carried out. An increase in antihelminthic activity of the preparations with respect to different laboratory models of helminthes was discovered and confirmed in experiments with sheep spontaneously infested by nematodes of gastrointestinal tract, with a decrease in substance dosage by a factor of 9-10.

Opisthorchosis is a widespread helminthiasis at the territory of Europe and Asia, accompanied by such complications as gallbladder dysfunction, cholecystitis, cholangitis, hepatic abscess, and cholelithiasis. Prasiquantel, a preparation used at present to treat opisthorchosis, is insufficiently effective. Mechanochemical preparation of the intermolecular complexes of antihelminthic agent albendazol with polysaccharide arabinogalactan is described. The activity of these complexes against opisthorchosis was studied in vivo in laboratory animals. The possibility of the development of new medical products based on albendazol exceeding prasiquantel is demonstrated.

Phytocompositions based on Gynostemma pentaphyllum (GP) and arabinogalactan (AG) were obtained by means of mechanochemical activation. The addition of AG into the mixture under treatment promotes the formation of water-soluble intermolecular complexes with increased biological assimilability of biologically active substances, and increases the solubility of the phytocomposition in water. In all activated samples, the extractability of saponins from GP increases by a factor of 3.4-4.7. The hypolipidemic action of GP-based samples was demonstrated for the hyperlipidemia model in mice after single intra-abdominal introduction of poloxamer-407. The introduction of GP/AG composition at a ratio of 1 : 2 (by mass) caused a decrease in the level of cholesterol and triglycerides by 56 and 63 %, respectively. For the model of high-lipid diet for rats, the hypolipidemic action of the phytocomposition under investigation was confirmed: the level of triglycerides and cholesterol decreased by 46 and 29 %, respectively, in comparison with reference animals kept to a fatty diet.

Promising multicomponent compositions of preparations for integrated protection of plants were obtained using the methods of mechanochemistry. Due to the use of polysaccharides, in particular arabinogalactan (from wood of Larix sibirica and Larix gmelinii), the obtained seed disinfectants based on tebuconazol are characterized by improved physicochemical, technological and biological parameters. Tests of the preparations under laboratory conditions provide evidence of the synergism of biological properties, which is exhibited as acceleration of the growth of crop plants, stability of the root system to diseases, and an increase in the crop capacity of spring wheat with a decrease in the consumption of the active substances in the preparations. It is shown that intermolecular complexes of tebuconazol based on arabinogalactan possess high biological activity with decreased consumption of the preparation.

Complexation of the derivative of 1,2,4-thiadiazole, exhibiting biological activity in therapy of Alzheimer's disease, with β-and hydroxypropyl-β-cyclodextrin was studied using the methods of isothermal saturation and UV spectroscopy in phosphate buffer solution (рН 7.4). It was shown that the formation of the complexes with stoichiometric composition 1 : 1 involves the inclusion of the benzene ring of guest molecule, which is held in the macrocyclic cavity of the host mainly by hydrophobic interactions. Hydroxypropyl-β-cyclodextrin exhibits higher complex-forming and solubilizing capacity in comparison with β-cyclodextrin with respect to the biologically active compound.

Composite materials based on chitosan with molecular mass 190 000 a.m.u. and hydroxyapatite with acerage particle size 20-30 nm with different filling degree were obtained. The optimal amount of hydroxyapatite (0.03 and 1 mass %) for modification providing an increase in film strength by 20 % was determined. Periodic change of the size of polymer grains during modification was revealed. The effect of such parameters as components ratio, compacting pressure and mold humidity on highly filled composite materials obtained by pressing was studied. The density, rupture and tensile strength, compression strength and apparent density of the obtained samples were determined.

Expediency of the application of results achieved in medicine, in the development of nanopharmaceutical materials with sharply increased antimicrobial activity, for plant cultivation was observed. It was established that these preparations provide plant protection against pathogens and unfavourable effects of abiotic nature. The stimulating action of bismuth and silver nanopreparations on the length of germs and roots of spring wheat exceeds the reference level by a factor of 1.2-1.3. The fungicide action of nanopreparations decreasing the development of the disease (root rot) by a factor of 2-4 was discovered. Optimal concentrations and standards of bismuth nanopreparation concumption for industrial tests in cereal production were proposed. Biologically active nanopreparation exceeds important seed disinfectants in efficiency, which opens the outlooks for import substitution in this area.