K. G. Bogolitsyn

Amino-Acid Composition of Arctic Brown Algae

The amino-acid composition and total nitrogen content in 25 samples of four commercial Arctic brown algae Saccharina latissima (L.) C. E. Lane, C. Mayes, Druehl & G. W. Saunders; Laminaria digitata (Hudson) J. V. Lamouroux; Fucus vesiculosus (L.); and Ascophyllum nodosum (L.) Le Jolis were studied. The use of brown algae not only as raw material for producing mono- and polysaccharides but also as a source for obtaining amino acids for the production of drugs and functional foods was recommended. Factors for calculating total nitrogen in protein that differed from the commonly accepted ones were proposed.

Supercritical fluid technologies in the chemistry of wood and its components

The advantages of application of supercritical fluid technologies at the stages of complex wood and plant processing are analyzed based on the modern concept of lignin-carbohydrate matrix formation.

Relationship of the structure and ion-exchange properties of polyelectrolyte complexes based on biopolymers

Ion-exchange properties of polyelectrolyte complexes based on lignosulfonates and chitosan were studied. Optimum conditions were found for preparing polymeric sorbents with the maximal sorption capacity for cationic and anionic pollutants.

Determination of natural aromatic acids using supercritical fluid chromatography

Derivatives of benzoic and cinnamic acids are secondary metabolites of plants, widely distributed in nature and possessing biological activity. Supercritical fluid chromatography (SFC) is shown to provide a high performance separation of nine most important representatives of this class of compounds with selectivity, dramatically different from the reversed-phase high-performance liquid chromatography. The retention and chromatographic separation parameters of analytes for four stationary phases of different nature are compared and the effect of supercritical fluid parameters and the composition of the mobile phase onto the chromatographic separation are analyzed. The optimal separation is found to be achieved when using a silica-based sorbent with 2-ethylpyridinium linked groups. The proposed approach for determination of the above-mentioned compounds is based on the combination of chromatographic separation with multiwavelength spectrophotometric detection and provides the detection limits in the range of 13.0–51.3 μg/L and the analysis duration about 2.5 min. The approach is successfully tested on real objects, such as different kinds of wine.

Influence of the conformation of biopolyelectrolytes on the morphological structure of their interpolymer complexes

Conformational transitions in complicated biopolyelectrolyte systems containing multiple interactions (ionic, dispersion, covalent and hydrogen) were investigated. The interrelations between the morphological structure of inter-polymer complexes of sodium lignosulfonate (alginate) with chitosan and the structure of the initial biopolyelectrolytes was established.

Fatty Acid Composition and Biological Activity of Supercritical Extracts from Arctic Brown Algae Fucus vesiculosus

The fatty acid composition of arctic brown algae was studied using supercritical (SC) fluid extraction. A method for fractionating the SC extract based on the differences in the solubility of its components (fatty acids, polyphenols) was proposed. The composition and biological activity of the fractions were studied.

Isolation and Structural Characterization of Cellulose from Arctic Brown Algae

A scheme for producing cellulose from the artic brown algae Fucus vesiculosus and Laminaria digitata was proposed. The physicochemical and structural features of the cellulose samples were studied and compared with those of celluloses from higher plants. Cellulose from Fucus vesiculosus was found primarily in the Iα-form; from Laminaria digitata, the Iα- and Iβ-forms. The studied samples were assumed to contain slightly crystalline cellulose with a structure similar to that of cellulose II. Its content was typically greatest in F. vesiculosus (58%).

Supercritical fluid technologies for the advanced processing of plant raw materials

Publications dedicated to the application of supercritical fluids in the advanced processing of plant raw materials for the production of a wide range of products such as ethanol, liquid and gaseous fuels, sugars, organic acids, and oils are reviewed and analyzed. The specific features of the supercritical fluid technologies and their advantages over the existing traditional methods for the processing of plant raw materials are demonstrated.

Physicochemical Properties of Conifer Lignins Using Juniperus communis as an Example

The physicochemical properties of slightly altered dioxane lignins isolated from Juniperus communis wood of different ages were studied. It was shown that the functional nature and reactivity of the lignins changed during lignification of the wood.

Ultramicroscopic composition and supramolecular structure of wood matrix

The ultramicroscopic composition and supramolecular structure of wood matrix were investigated by methods of electron and atomic force microscopy (AFM). New data on specific features of the composition and cell wall structure of Juniper wood (Juniperus communis L.) were obtained. Native lignin was found to be water soluble. It was also shown that lignin does not constitute a continuous matrix between cellulose fibrils, but is deposited as spherical particles.