[Hepatoprotective effects of extracts and polysaccharides from seaweed].

Antioxidants of natural origin are considered as possible agents for prevention and treatment of liver diseases. Marine algae and in particular their extracts and obtained from them sulfated polysaccharides are significant sources of natural antioxidants. The recent data on the effect of the extracts and sulfated polysaccharides of seaweed on the functional activity of the liver with injuries induced by CCl4, some drugs (paracetamol, diclofenac), N-nitrosocompounds, aflatoxin are presented in the review. Particular attention is paid to the effect of sulfated polysaccharides and in particular fucoidans on the functional activity of the liver in patients with chronic viral hepatitis C. Fucoidan is highly safe and active not only as an antioxidant but also as an inhibitor of HCV replication, has antiinflammatory and immunomodulating effects. The data of the review allow to conclude that seaweed extracts and sulfated polysaccharides may be a basis for development of new generation drugs in the future for the treatment and prevention of liver diseases.

[Efficiency of a new synbiotic drink in treatment of chronic diseases of gastrointestinal tract and concomitant dysbacteriosis].

The efficacy of a novel synbiotic drink in the complex therapy of patients withchronic diseases of the gastrointestinal tract and concominant intestinal dysbacteriosis was investigated in a randomized trial. The synbiotic drink contains a probiotic strain of bifidobacteria and Fucus evanescens polysaccharides with prebiotic activity and broad spectrum of the biological action on the patients. The use of the synbiotic drink provided more evident reduction of the clinical symptomes, more efficient recovery of the intestinal microflora and higher percentage of the patients cure vs. the routine therapy and the therapy with inclusion of sour milk bifidobacterin.

[Extracellular beta-D-glucosidase of the Penicillium canescens marine fungus].

Extracellular beta-D-glucosidase was isolated in a homogeneous state from the Penicillium canescens marine fungus. According to SDS-electrophoresis, the molecular weight of the enzyme was 64 kDa and the maximal activity was observed at pH 5.2 and 70 degrees C. Glucosidase catalyzed the hydrolysis of beta-glycosidic bonds both in glycosides and in glucose disaccharides and had transglycosylation activity. The enzyme can be used for the deglycosylation of natural glycosides and in enzymatic synthesis of new carbon-containing compounds.

[Influence of intravenous injection of fucoidan from brown seaweed Fucus evanescens by plasma rabbits anticoagulant activity and neutralisation by sulphate protamin of fucoidans antithrombin activity in vitro].

With fucoidan from Fucus evanescens dose increase from 1 to 5 mg/kg plasma coagulation time in test A(see symbol)TB increases. Sulphate protamin in final concentration 0.67-1.35 mkg/ml will neutralise antithrombin activity of fucoidans from brown seaweed Fucus evanescens and Laminaria cichorioides. The gravimetrichesky relation for the investigated samples makes an antidot/anticoagulant 1.

[Effect of sulfated polysaccharides from brown algae on proliferative and cytotoxic activity of mice splenocytes].

AIM: Study effect of fucoidans from brown algae on proliferative and cytotoxic activity of mice splenocytes. MATERIALS AND METHODS: Proliferative and cytotoxic activity of mice splenocytes in vitro and ex vivo were studied in lymphocyte blast transformation reaction and in cytotoxic MTT-test on K562 human erythroblast leucosis cell line. Microphotography and microscopy were performed by using Axiocam HS photosystem and computer program AxioVision 4 (Germany). RESULTS: Fucoidans from brown algae Fucus evanescens, Laminaria cichorioides and Laminaria japonica in vitro and ex vivo systems were established to increase proliferative activity of mice splenocytes which is evidenced by an increase of stimulation index. Results of in vitro and ex vivo cytotoxic activity studies demonstrate that fucoidans which are various by chemical structure stimulate activity of NK-cells and facilitate an increase of splenocyte cytotoxic potential level against NK sensitive K562 cell line. CONCLUSION: The data obtained from the study demonstrate an ability of fucoidans to stimulate splenocyte proliferation and NK-cell killer activity, and studies of relation between structure and functions of sulfated polysaccharides facilitate a more detailed understanding of aspects of their mechanism of action on innate immunity system, thus providing the basis for development of new immunobiologic preparations - modifiers/agonists of innate immunity.

[Antithrombotic and hemorrhagic activities of fucoidan isolated from Fucus evanescens brown algae].

The antithrombotic and hemorrhagic activities of fucoidan with molecular weight within 20 - 40 kD isolation from Fucus evanescens seaweed have been investigated. The antithrombin activity of fucoidan is 41 +/- 9 aIIa IU/mg and the anti-factor Oà activity is 38 +/- 8 aOà IU/mg. The antithrombin and anti-factor Oà activities of plasma, antithrombotic activity (100% prevention of formation of a blood clot observed at a dose of 10 mg/kg), and hemorrhagic activity (to a lesser degree, than that of unfractionated heparin in comparable antithrombotic activity doses) increase as the doses of fucoidan increases from 2.5 to 10 mg/kg at intravenous injection in rats.

[Production of cytokines by murine bone marrow dendritic cells in vitro mediated by sulfated polysaccharides obtained from sea brown algae].

AIM: To assess in vitro cytokine production by murine bone marrow dendritic cells (DC) matured under the effect of sulfated polysaccharides--fucoidanes from sea brown algae Laminaria cichorioides and Laminaria japonica. MATERIALS AND METHODS: CBA line mice were used to obtain bone marrow origin precursors of DC. Isolation and study of chemical composition and structure of fucoidanes were performed using modern research methods. Expression of surface markers was determined by flow cytometry (FACS-analysis) using monoclonal antibodies to respective antigens. Levels of cytokine production were measured by t-ELISA using kits manufactured by Biosource (Belgium). RESULTS: I was determined that fucoidans induce maturation of DC that was evident by expression of terminal differentiation marker CD83, activation marker CD38, enhanced expression of costimulating CD86, antigen-presenting MHC II and adhesive CD11c molecules. Fucoidanes stimulate DC to produce proinflammatory (TNF-alpha, IL-6, IL-1beta) and regulatory (IL-12) cytokines. Fucoidanes enhance expression of TLR-2 and TLR-4 but do not influence on expression of TLR-9. CONCLUSION: It was shown that fucoidanes from sea brown algae L. cichorioides and L. japonica activate innate immunity system that is evident by enhanced expression of surface molecules associated with DC maturation and increased production of proinflammatory and regulatory cytokines by DC. Enhanced expression of TLR-2 and TLR-4 allows to suppose that studied fucoidanes could have anti-infective effect in vivo.

[Inhibition of adherence of Corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases from marine hydrobiontes].

A possibility of adhesion inhibition of Corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases of marine hydrobiontes was investigated using alpha-galactosidase from marine bacterium Pseudoalteromonas sp. KMM 701, total enzyme preparation and beta-1,3-glucanase from marine fungi Chaetomium, total enzyme preparation and beta-1,3-glucanase from marine mollusk Littorina kurila, and total enzyme preparation from crystalline style of marine mollusk Spisula sachalinensis were used. The enzymes were added to test-tubes containing buccal epithelial cells and/or the toxigenic bacterial strain C. diphtheriae No 1129, v. gravis. All the investigated enzymes were able to abort C. diphtheriae adherence, to human buccal epithelocytes. Inhibition of adhesion was more pronounced in the case of treatment of epithelocytes with highly purified enzymes of marine hydrobiontes in comparison with total enzyme preparations. The significant inhibition of C. diphtheriae adhesion was observed when the enzymes were added to the epithelocytes with the attached microorganisms. The results obtained show that glycoside hydrolases of marine hydrobiontes degrade any carbohydrates expressed on cell surface of bacterium or human buccal epithelocytes, impair unique lectin-carbohydrate interaction and prevent the adhesion.

[Antiviral activity of sulfated polysaccharide from the brown algae Laminaria japonica against avian influenza A (H5N1) virus infection in the cultured cells].

The antiviral activity of the sulfated polysaccharide fucoidan from the brown sea algae Laminaria japonica against infection caused by highly virulent avian influenza virus (Alduck/Novosibirsk/02/05, H5N1) in the sensitive pig embryo kidney cell cultures was studied. Fucoidan was ascertained to have no cytotoxic activity and to show virucidal activity against influenza A/H5N1 virus. When given at concentrations of 50 to 500 microg/ml, fucoidan protected the cell cultures from the cytopathogenic activity of influenza virus in a dose of 0.01 TCID50/1.0 ml and was able to suppress influenza A/H5N1 virus production within 24 hours of infection when prophylactic and therapeutic-and-prophylactic treatment regimens were used.

[Distribution of O-glycosylases in marine fungi of the Sea of Japan and the Sea of Okhotsk: characterization of exocellular N-acetyl-beta-D-glucosaminidase of the marine fungus Penicillium canescens].

The capacity to produce exocellular enmzymes was studied for 92 samples of fungi from various marine habitats in the Sea of Okhotsk (78 strains) and the Sea of Japan (14 strains). Strains producing highly active glycanases and glycosidases were found. Synthesis of O-glycosylhydrolases was stimulated by addition of laminaran to the nutrient medium. Highly purified N-acetyl-beta-D-glucosaminidase was isolated from the marine fungus Penicillium canescens. The molecular weight of the enzyme determined by SDS-Na-electrophoresis was 68 kDa. The enzyme displayed maximum activity at pH 4.5 and temperature 45 degrees C. Inactivation half-time of the enzyme at 50 degrees C was 25 min. N-acetyl-beta-D-glucosaminidase hydrolyzed both beta-glucosaminide and beta-galactosaminide bonds and possessed a high transglycosylazing activity.

[Effect of fucoidan on the ultrastructure of mesophyll cells of Datura stramonium L. and accumulation of potato virus X in them].

Influence of fucoidan from brown alga Fucus evanescens C. Ag. on the development of infection induced by potato virus X (PVX) in Datura stramonium leaves was studied. It as been shown that 24 h after the treatment of the leaves with fucoidan and following infection of them with PVX the accumulation of virus particles in infected cells during early infection period was substantially less than that in untreated control. Using ultrastructure-morphometric analysis, it has been established that fucoidan treatment increases at protein-synthesizing capability of cells (nucleolus dimension, amount of mitochondria and rough endoplasmic reticulum membranes become increased). At the same time, the fucoidan treatment causes some activation of lytic compartment which leads to destruction of virus particles and, therefore, might be considered as one of fucoidan-dependent protective mechanisms limiting virus accumulation in cells. Fucoidan stimulation of the formation of PVX-specific laminated structures capable of virus particles binding is possibly another induced antiviral cell mechanism, preventing from virus reproduction and transposition.

[Catalytic properties of endo-1,3-beta-D-glucanase from the Vietnamese edible mussel Perna viridis].

A beta-1,3-glucanase with a molecular mass of 33 kDa was isolated in the homogeneous state from a crystalline stalk of the commercially available Vietnamese edible mussel Perna viridis. It hydrolyzes beta-1,3-bonds in glucans and is capable of catalyzing the transglycosylation reaction. The beta-1,3-glucanase has a K(m) value of 0.3 mg/ml for the hydrolysis of laminaran and shows a maximum activity in the pH range from 4 to 6.5 and at 45 degrees C. Its half-inactivation time is 180 min at 45 degrees C and 20 min at 50 degrees C. The enzyme was ascribed to glucan-endo-(1-3)-beta-D-glucosidases (EC 3.2.1.39). The enzyme could be used in the structure determination of beta-1,3-glucans and enzymatic synthesis of new carbohydrate-containing compounds.

[O-glycosylhydrolases of embryos of the sea urchin Strongylocentrotus intermedius and effect of some natural substances on their biosynthesis].

Embryos of sea urchin Strongylocentrotus intermedius have been revealed to contain o-glycosylhydrolases: highly active 1,3-beta-D-glucanase and alpha-D-mannosidase as well as a lower activity of beta-D-glucosidase and beta-D-galactosidase. Dynamics of changes of the enzyme activities has been studied at various stages of the sea urchin embryo development. There also have been studied effects of some substances (natural fucoidans, beta-1,3; 1,6-glucans formed by enzymatic synthesis as well as a protein inhibitor of marine mollusc endo-1,3-beta-D-glucanases) on development of the embryos and biosynthesis of 1,3-beta-D-glucanase and alpha-D-mannosidase.

[Fermentative production of 1,3;1,6-beta-D-glucan (translam), a labeled immunostimulant and investigation of its pharmacokinetics and pharmacodynamics].

Production of labeled translam from a marine mollusk was provided by the use 1,3-beta-D-glucanase. The pharmacokinetics of the 14C-translam metabolism in the experimental rats by the accumulation level and the retention time in the organs and tissue and the excretion rate with the feces and urine was of the same character as that of carbohydrates and in particular that of glucose, whereas the excretion of translam mainly with the urine was likely evident of its incomplete hydrolysis after the intramuscular administration.

[Inhibiting effects of fucoidans on Hantaan virus adsorption on a model of peritoneal macrophages in vitro].

A model of peritoneal macrophages was used to study the effect of fucoidans from brown seaweeds on the adsorption of Hantaan virus. Fucoidans were found to have antiviral activity, but to differ in the inhibition of hantavirus adsorption, which was associated with their structural features. The mechanism of their action is assumed to be shown via ligand-receptor interaction with certain cell membrane receptors and via blockage of hantavirus glycoproteins (G1 and G2), resulting in adsorption inhibition and preventing viral penetration into the macrophages.

[The action of Laminaria japonica extracts on 1,3-beta-D-glucanase, a digestive enzyme of the Strongylocentrotus intermedius sea urchin].

Nutritional attractiveness of the brown alga Laminaria japonica for the sea urchin Strongylocentrotus intermedius was studied. The composition of L. japonica was analyzed after one and two years of its life under natural conditions, in its seedlings, and in the alga partially degraded by natural factors. Substances extracted with various solvents were tested for the presence of inhibitors and activators of 1,3-beta-D-glucanase, a digestive enzyme of the sea urchin. Ethanolic extract of freshly harvested L. japonica was found to suppress the enzyme activity. Substances present in ethanolic extracts of the alga after one or two years of its life cycle and in the alga, partly degraded by natural factors, activated the sea urchin enzyme. This fact is in agreement with earlier natural observations concerning the nutritional attractiveness of such L. japonica samples for Strongylocentrotus intermedius.