A low-molecular derivative of the polysaccharide (5 kDa) was obtained and its cytokine-inducing and anti-inflammatory activity was studied by free radical depolymerization of chitosan (110 kDa). It was shown that high-molecular chitosan in vitro inhibited the synthesis of anti-inflammatory cytokine, the tumor necrosis factor alpha induced by endotoxin. In the case of peroral introduction to experimental animals, high- and low-molecular chitosans stimulated synthesis of the anti-inflammatory cytokine IL-10 in the blood serum of mice; in this case, the activity of the high-molecular derivative was two times higher as compared with the initial polysaccharide. With peroral introduction, the initial polysaccharide (50 mg/kg) and its derivative inhibited the development of chemically induced inflammation of experimental animals' large intestines, which was manifested as a decrease in the affected area and the degree of damage to the large intestine wall, as well as a two-fold reduction of myeloperoxidase activity. According to morphological and biochemical characteristics, the effect of chitosans was similar to that of a hormone anti-inflammatory drug, prednisolone.

A method for preparing multilayer film composites based on chitosan has been developed by the example of polymer pairs: chitosan–hyaluronic acid, chitosan–alginic acid, and chitosan–carrageenan. The structure of the composite films is characterized by X-ray diffractometry and scanning electron microscopy. It is shown that the deposition of a solution of hyaluronic acid, alginic acid, or carrageenan on a chitosan gel film leads to the formation of a polyelectrolyte complex layer at the interface, which is accompanied by the ordering of chitosan chains in the surface region; the microstructure of this layer depends on the nature of contacting polymer pairs.

Organomodified aluminosilicates for purification of biological solutions were prepared from a natural zeolite. The synthesis was performed by chemical deposition of chitosan on the zeolite surface followed by successive treatment with a solution of copper sulfate and a solution of potassium ferricyanide. The composition of sorbents was determined by elemental analysis. The physicochemical properties of the starting and modified zeolites were studied by the positron annihilation spectroscopy, IR spectroscopy, powder X-ray diffraction, and scanning electron microscopy, while the adsorption properties were examined by sorption of brilliant green. The adsorption behavior of the zeolites toward endotoxins was assessed. The sorbent containing the ferricyanide-chitosan complex was found to have the highest sorption capacity for lipopolyssacharides (endotoxins).

The physicochemical properties and morphology of κ, κ/β, κ/ι, and λ-carrageenans from red algae of the families Gigartinaceae and Tichocarpaceae were analyzed and compared. The highest molecular weights (527 kDa) and negative electrokinetic potentials (–36.4 mV) were obtained for x -carrageenan, which had the conformation of a disordered coil whereas fine threads of κ and κ/β-carrageenans formed long fibrils of width up to 16 nm that were more heterogeneous in the latter instance whereas κ/ι-carrageenan formed a fibrous network structure.

Successive extraction of phycobiliproteins (PBP) by two methods (0.1 M phosphate buffer and 1.5% NaNO 3 solution) and polysaccharides from reproductive (cystocarps) and sterile red alga A. flabelliformis was performed. The yield of phycoerythrin (PE) was twice as great for extraction by NaNO 3 than by phosphate buffer. The yield of polysaccharides was 1.6 times greater for successive extraction than without preliminary extraction of PBP from the alga. The polysaccharide content in sterile plants was 1.5 times less than in alga with cystocarps regardless of the PBP extraction method. According to IR spectral data, the polysaccharide from sterile plants was κ-carrageenan; from alga with cystocarps, κ,ι-carrageenan.

The paper provides results of examination of 32 patients aged from 44 to 64 years diag-nosed with ischemic heart disease (stable angina of functional class II-III). The studies have been tar-geted to identify effects from bioactive food additive ‘Carrageenan-DV’ on the lipid exchange indices and chronic inflammation markers. The drug was prescribed in 250 mg capsules during 20 days. Up-on completion of the bioactive additive intake, the total cholesterol and low-density lipoprotein cho-lesterol and atherogenic index have decreased in blood serum to normal ranges. There were decreased levels of C-reactive protein, total leukocytes and fibrinogen. The authors believe the bioactive additive ‘Carrageenan-DV’ may be used as additional source of dietary fibers in the integrated treatment of patients with cardiovascular diseases.

The formation process of soluble chitosan (C)/κ-carrageenan (K) complexes was studied. It was shown that soluble complexes were obtained preferentially by mixing the starting components at given ratios whereas soluble complexes were formed only over a narrow range of starting-component ratios by titration of K with C. The formation of C/K polyelectrolyte complexes was confirmed by gel-permeation chromatography and centrifugation in a Percoll gradient. The formation process of C/K complexes depended on the C molecular weight and the concentrations and ratios of starting polysaccharides. It was shown that unbound components in addition to the complex remained in the mixture upon mixing carrageenan with high-molecular-weight C (C-HM) in 1:1.5 and 1:30 ratios (mol/mol) whereas low-molecular-weight C (C-LM) was bonded completely to the polyanion.

Effect of chitosan on the mesophyll cell ultrastucture and activity of hydrolases in leaves of tobacco cv. Samsun was studied. It was shown that, in many cells, chitosan treatment stimulated the protein-synthesizing apparatus (nucleolus dimension and amount of both mitochondria and rough endoplasmic reticulum membranes increased) and, at the same time, caused some activation of lytic compartment expressed in the stimulation of the formation of dictyosomes, smooth ER elements and cytoplasmic vacuoles, which are all prominent constituents of this compartment. In biochemical experiments, it was established that chitosan substantially enhanced activity of hydrolases (acid phosphatase, RNase, proteases) in the leaves as compared to untreated leaves. In some cells chitosan treatment caused considerable destructive changes (condensation of nuclear chromatin, collapse of cytoplasm and so on) that can be classified as a result of programmed cell death development.

Проведен ферментативный (действие лизоцима) и химический (пероксид водорода) гидролиз хитозанов с различной степенью ацетилирования (СА): 25, 17, 1.5%. Очистку и фракционирование продуктов гидролизов проводили методами диализа, ультрафильтрации и гельпроникающей хроматографии. Получены низкомолекулярные (НМ) производные полисахарида с молекулярными массами от 17 до 2 кДа. Изучена их антивирусная активность в отношении вируса табачной мозаики (ВТМ) и показано, что данные образцы ингибируют образование локальных некрозов, индуцированных вирусом, на 50–90%. Антивирусная активность НМ-хитозанов существенно возрастает с уменьшением степени их полимеризации. При этом продукты ферментативного гидролиза обладают меньшей активностью, чем образцы хитозанов, полученные в результате химического гидролиза. Установлено, что проявление антивирусной активности слабо зависит от степени ацетилирования образцов.