Comparative study of HIV-1 inhibition efficiency by carrageenans from red seaweeds family gigartinaceae, Tichocarpaceae and Phyllophoraceae.

The efficiency of human immunodeficiency virus-1 (HIV-1) inhibition by sulfated polysaccharides isolated from the various families of red algae of the Far East Pacific coast were studied. The anti-HIV-1 activity of kappa and lambda-carrageenans from Chondrus armatus, original highly sulfated X-carrageenan with low content of 3,6-anhydrogalactose from Tichocarpus crinitus and i/κ-carrageenan with hybrid structure isolated from Ahnfeltiopsis flabelliformis was found. The antiviral action of these polysaccharides and its low-weight oligosaccharide was compared with commercial κ-carrageenan. Here we used the HIV-1-based lentiviral particles and evaluated that these carrageenans in non-toxic concentrations significantly suppress the transduction potential of lentiviral particles pseudotyped with different envelope proteins, targeting cells of neuronal or T-cell origin. The antiviral action of these carrageenans was confirmed using the chimeric replication competent Mo-MuLV (Moloney murine leukemia retrovirus) encoding marker eGFP protein. We found that X-carrageenans from T. crinitus and its low weight derivative and λ-carrageenan from C. armatus effectively suppress the infection caused by retrovirus. The obtained data suggest that the differences in the suppressive effect of carrageenans on the transduction efficiency of HIV-1 based lentiviral particles may be related to the structural features of the studied polysaccharides.

The limitations of automatically generated curricula for continual learning.

In many applications, artificial neural networks are best trained for a task by following a curriculum, in which simpler concepts are learned before more complex ones. This curriculum can be hand-crafted by the engineer or optimised like other hyperparameters, by evaluating many curricula. However, this is computationally intensive and the hyperparameters are unlikely to generalise to new datasets. An attractive alternative, demonstrated in influential prior works, is that the network could choose its own curriculum by monitoring its learning. This would be particularly beneficial for continual learning, in which the network must learn from an environment that is changing over time, relevant both to practical applications and in the modelling of human development. In this paper we test the generality of this approach using a proof-of-principle model, training a network on two sequential tasks under static and continual conditions, and investigating both the benefits of a curriculum and the handicap induced by continuous learning. Additionally, we test a variety of prior task-switching metrics, and find that in some cases even in this simple scenario the a network is often unable to choose the optimal curriculum, as the benefits are sometimes only apparent with hindsight, at the end of training. We discuss the implications of the results for network engineering and models of human development.

HIPPO: HIstogram-based Pseudo-POtential for scoring protein-ssRNA fragment-based docking poses.

BACKGROUND: The RNA-Recognition motif (RRM) is a protein domain that binds single-stranded RNA (ssRNA) and is present in as much as 2% of the human genome. Despite this important role in biology, RRM-ssRNA interactions are very challenging to study on the structural level because of the remarkable flexibility of ssRNA. In the absence of atomic-level experimental data, the only method able to predict the 3D structure of protein-ssRNA complexes with any degree of accuracy is ssRNA'TTRACT, an ssRNA fragment-based docking approach using ATTRACT. However, since ATTRACT parameters are not ssRNA-specific and were determined in 2010, there is substantial opportunity for enhancement. RESULTS: Here we present HIPPO, a composite RRM-ssRNA scoring potential derived analytically from contact frequencies in near-native versus non-native docking models. HIPPO consists of a consensus of four distinct potentials, each extracted from a distinct reference pool of protein-trinucleotide docking decoys. To score a docking pose with one potential, for each pair of RNA-protein coarse-grained bead types, each contact is awarded or penalised according to the relative frequencies of this contact distance range among the correct and incorrect poses of the reference pool. Validated on a fragment-based docking benchmark of 57 experimentally solved RRM-ssRNA complexes, HIPPO achieved a threefold or higher enrichment for half of the fragments, versus only a quarter with the ATTRACT scoring function. In particular, HIPPO drastically improved the chance of very high enrichment (12-fold or higher), a scenario where the incremental modelling of entire ssRNA chains from fragments becomes viable. However, for the latter result, more research is needed to make it directly practically applicable. Regardless, our approach already improves upon the state of the art in RRM-ssRNA modelling and is in principle extendable to other types of protein-nucleic acid interactions.

Experiences with a training DSW knowledge model for early-stage researchers.

Background: Data management is fast becoming an essential part of scientific practice, driven by open science and FAIR (findable, accessible, interoperable, and reusable) data sharing requirements. Whilst data management plans (DMPs) are clear to data management experts and data stewards, understandings of their purpose and creation are often obscure to the producers of the data, which in academic environments are often PhD students. Methods: Within the RNAct EU Horizon 2020 ITN project, we engaged the 10 RNAct early-stage researchers (ESRs) in a training project aimed at formulating a DMP. To do so, we used the Data Stewardship Wizard (DSW) framework and modified the existing Life Sciences Knowledge Model into a simplified version aimed at training young scientists, with computational or experimental backgrounds, in core data management principles. We collected feedback from the ESRs during this exercise. Results: Here, we introduce our new life-sciences training DMP template for young scientists. We report and discuss our experiences as principal investigators (PIs) and ESRs during this project and address the typical difficulties that are encountered in developing and understanding a DMP. Conclusions: We found that the DS-wizard can also be an appropriate tool for DMP training, to get terminology and concepts across to researchers. A full training in addition requires an upstream step to present basic DMP concepts and a downstream step to publish a dataset in a (public) repository. Overall, the DS-Wizard tool was essential for our DMP training and we hope our efforts can be used in other projects.

Carrageenans and Their Oligosaccharides from Red Seaweeds Ahnfeltiopsis flabelliformis and Mastocarpus pacificus (Phyllophoraceae) and Their Antiproliferative Activity.

Comparative structural analysis of gelling polysaccharides from A. flabelliformis and M. pacificus belonging to Phyllophoraceae and the effect of their structural features and molecular weight on human colon cancer cell lines (HT-29, DLD-1, HCT-116) was carried out. According to chemical analysis, IR and NMR spectroscopies, M. pacificus produces kappa/iota-carrageenan with a predominance of kappa units and minor amounts of mu and/or nu units, while the polysaccharide from A. flabelliformis is iota/kappa-carrageenan (predominance of iota units) and contains negligible amounts of beta- and nu-carrageenans. Iota/kappa- (Afg-OS) and kappa/iota-oligosaccharides (Mp-OS) were obtained from the original polysaccharides through mild acid hydrolysis. The content of more sulfated iota units in Afg-OS (iota/kappa 7:1) was higher than in Mp-OS (1.0:1.8). The poly- and oligosaccharides up to 1 mg/mL did not show a cytotoxic effect on all tested cell lines. Polysaccharides showed an antiproliferative effect only at 1 mg/mL. Oligosaccharides had a more pronounced effect on HT-29 and HCT-116 cells than the original polymers, while HCT-116 cells were slightly more sensitive to their action. Kappa/iota-oligosaccharides exhibit a greater antiproliferative effect and more strongly decrease the number of colonies forming in HCT-116 cells. At the same time, iota/kappa-oligosaccharides inhibit cell migration more strongly. Kappa/iota-oligosaccharides induce apoptosis in the SubG0 and G2/M phases, while iota/kappa-oligosaccharides in the SubG0 phase.

Structural peculiarities of carrageenans from Far Eastern red seaweed Mazzaella parksii (Gigartinaceae).

The sulfated polysaccharides from cystocarpic plants of Mazzaella parksii were studied. Fractionation at a given KCl concentration allowed us to assume, and stepwise fractionation to prove, that these polysaccharides consisted of several carrageenans that differed in structure and molecular weight. As a result of stepwise fractionation with KCl, nine gelling (1-9) and one non-gelling (10) fractions were obtained. Using IR spectroscopy, it was shown that fractions 3, 4 and 5 were kappa/iota-, kappa- and kappa/beta-carrageenans, respectively. The structures of the main fractions 1, 2, 9 and 10 were investigated in more detail by methylation, NMR spectroscopy and mass spectrometry. Fractions 1 and 2 were hybrid kappa/iota-carrageenans with kappa:iota ratio 79:21 and 63:37, respectively. At the same time, fraction 9 contained kappa-, iota- and small amounts of nu-carrageenans. The fraction 10 had complex structure and was built from kappa-, iota-, beta-, mu- and nu-carrageenans and included agar-like structure, which explained the inability of this fraction to gel at 15 % KCl. It was shown that isolated polysaccharides activated the classical pathway of complement system, increasing the concentration of C1 inhibitor of serine protease by 50 % compared with the negative control.

Antiherpetic Activity of Carrageenan Complex with Echinochrome A and Its Liposomal Form.

Herpes simplex virus (HSV) infections, the incidence of which is still widespread throughout the world, are actualizing the search and development of new, more effective antiherpetic drugs. The development of multifunctional drug delivery systems, including liposome-based ones, has become a relevant and attractive concept in nanotechnology. The ability of complexes of κ- and Σ-carrageenans (CRGs)-sulfated polysaccharides of red algae, with echinochrome A (Ech), as well as the liposomal form of the Σ-CRG/Ech complex-to inhibit different stages of HSV-1 infection in Vero cells was studied. By quantum chemical calculations, it was shown that CRG forms stable complexes with Ech. We have shown that complexes of κ-CRG/Ech and Σ-CRG/Ech exhibit highest virucidal activity with a selectivity index (SI) of 270 and 350, respectively, and inhibition of virus-cell interaction (SI of 83 and 32, respectively). The liposomal form of the Σ-CRG/Ech complex after virus adsorption and penetration to cells effectively reduced the HSV-1 plaque formation. The virus-inhibiting activity of the liposomal form of the Σ-CRG/Ech complex was three times higher than that of the Σ-CRG/Ech complex itself. Obtaining CRGs/Ech complexes and their liposomal forms can become the basis of a successful strategy for the development of promising antiherpetic drugs.

The Anti-Inflammatory Effect of Carrageenan/Echinochrom Complex at Experimental Endotoxemia.

The anti-inflammatory effects of the CRG/Ech complex in LPS-induced endotoxemia were investigated in vivo in mice and in vitro in LPS-stimulated RAW 264.7 cells and peritoneal macrophages. The results indicated that the CRG/Ech complex suppressed the LPS-induced inflammatory response by reducing the production of ROS and NO in the macrophages. Furthermore, the in vivo experiment indicated that the CRG/Ech complex minimized disorders of the physiological and metabolic processes in mice subjected to LPS intoxication and reduced the levels of proinflammatory cytokines in the mouse serum. The preventive administration of the CRG/Ech complex to mice prevented endotoxin-induced damage in the mouse model of endotoxemia, increased the mice's resistance to LPS, and prevented increases in the levels of proinflammatory cytokines (TNFα). In this work, we showed by the molecular docking that Ech interacted with carrageenan, and that H-donor and H-acceptor bonds are involved in the formation of the complex.

Influence of the Structural Features of Carrageenans from Red Algae of the Far Eastern Seas on Their Antiviral Properties.

The structural diversity and unique physicochemical properties of sulphated polysaccharides of red algae carrageenans (CRGs), to a great extent, determine the wide range of their antiviral properties. This work aimed to compare the antiviral activities of different structural types of CRGs: against herpes simplex virus type 1 (HSV-1) and enterovirus (ECHO-1). We found that CRGs significantly increased the resistance of Vero cells to virus infection (preventive effect), directly affected virus particles (virucidal effect), inhibited the attachment and penetration of virus to cells, and were more effective against HSV-1. CRG1 showed the highest virucidal effect on HSV-1 particles with a selective index (SI) of 100. CRG2 exhibited the highest antiviral activity by inhibiting HSV-1 and ECHO-1 plaque formation, with a SI of 110 and 59, respectively, when it was added before virus infection. CRG2 also significantly reduced the attachment of HSV-1 and ECHO-1 to cells compared to other CRGs. It was shown by molecular docking that tetrasaccharides-CRGs are able to bind with the HSV-1 surface glycoprotein, gD, to prevent virus-cell interactions. The revealed differences in the effect of CRGs on different stages of the lifecycle of the viruses are apparently related to the structural features of the investigated compounds.

New Insights into the Structure of Kappa/Beta-Carrageenan: A Novel Potential Inhibitor of HIV-1.

New insights into the structure of the hybrid κ/ß-carrageenan (κ/ß-CRG) of the red alga Tichocarpus crinitus have been obtained. Carrageenan oligosaccharides were prepared through the chemical and enzymatic depolymerization of κ/ß-CRG with κ-carrageenase and its the enzyme-resistant fraction. The composition and distribution of the repetition units of κ/ß- CRG were investigated by using the negative ion tandem MALDI-TOFMS and ESIMS method, which made it possible to prove and characterize the hybrid structure of this polysaccharide. An analysis revealed the blockwise distribution of the long ß-blocks along the polysaccharide chain, with the inclusion of κ/ß, µ/ν-blocks and some ι-blocks. Furthermore, the desulfated κ/ß-CRG was shown to contain of -G-D- repeating units up to 3.5 kDa. Previous studies have demonstrated that CRGs suppress the replication of several viruses. Here, we established that κ/ß-CRG and its oligosaccharides significantly inhibit the transduction efficiency of replication-defective lentiviral particles pseudotyped with the envelope proteins of three different viruses. We found that the polysaccharide and its oligosaccharides strongly reduced the transduction efficiency of lentiviral particles pseudotyped with GP160-the envelope protein of the human immunodeficiency virus HIV-1-when added to T-lymphocyte Jurkat cells. The CRG oligosaccharides displayed significantly higher antiviral activity.

Inhibitory Effects of Carrageenans on Endotoxin-Induced Inflammation.

The inhibitory effects of carrageenans (CRGs) on lipopolysaccharide (LPS) induced inflammation in a mouse model of endotoxemia and in complex therapy of patients with enteric infections of Salmonella etiology were studied. The atomic force microscopy (AFM) examination of LPS and its mixture with CRGs showed that the LPS morphology is significantly changed under the action of κ- and κ/ß-CRGs. CRGs were able to increase the synthesis of anti-inflammatory interleukin 10 (IL-10) in vitro, and, at low concentrations, their activity in the mixture with LPS was higher. The protective effect of CRGs against Escherichia coli LPS was studied in vivo by monitoring the biochemical and pathomorphological parameters. The κ- and κ/ß-CRGs and food supplement "Carrageenan-FE" increased the nonspecific resistance of mice to E. coli LPS at the expense of the inhibition of processes of thymus involution, adrenals hypertrophy, thyroid atrophy, hypercorticoidism, glycogenolysis, and lactate acidosis. The estimation of the therapeutic action of food supplement Carrageenan-FE in complex therapy of patients with enteric infections of Salmonella etiology is given. Carrageenan-FE restores the system of hemostasis and corrects some biochemical indicators and parameters in the immune systems of patients. These results allow us to hope for the practical application of CRGs for lowering the endotoxemia level in patients under the development of the infectious process caused by Gram-negative bacteria.

Efficacy assessment of the scheme for prevention of herpesvirus infection manifestations in the oral cavity of patients with herpes-associated generalized moderate severity periodontitis.

OBJECTIVE: The aim: Efficacy assessment of herpesvirus infection drug prophylaxis (HVI) manifestations in the mouth of patients with chronic herpes-associated generalized periodontitis (CHGP) of moderate severity during and shortly after closed curettage. PATIENTS AND METHODS: Materials and methods: The total of 87 patients with CHGP of moderate severity aged 35-60 years were examined and divided into groups according to the presence of HVI: Group I (main) included 48 patients who had herpesvirus infection; group II (comparison) - 39 patients who were not found herpesvirus infection. Group III was formed based on the data of out-patient medical reports retrospective analysis and was used to compare the number of complication cases. The control group included 20 patients with intact periodontium. Prior to treatment, patients in group I, was additionally assigned multicomponent phytocomplex. The treatment efficacy was assessed by the concentration dynamics of A, G, M immunoglobulins, circulating immune complexes (CIC) and sIgA, hygienic and periodontal indices, as well as by the dynamics of gum fluid and the recovery terms. RESULTS: Results: The study on the dynamics of clinical indices and some humoral immunity indices confirmed the main group patients after closed curettage had positive shifts in sIgA, IgA, IgG, IgM and CIC levels. Their indices did not have a statistically significant difference with similar indicators of the comparison group. In group I, complications in the form of HVI manifestations in the buccal mucous membrane (BMM) were found in 8.33% of patients, which had a statistically significant difference (p <0.001) from the percentage of patients with HVI, with complications in group III (35.71% ). The recovery terms for patients in group I were by 16.7% shorter than the similar terms in group III. CONCLUSION: Conclusions: The results obtained indicate that the phytocomplex used by us can be applied as an immunomodulatory agent for the prevention of herpes virus infection manifestations in the oral cavity of patients with interventions in BMM and periodontal tissues.

Immunomodulating Properties of Carrageenan from Tichocarpus crinitus.

Several in vivo immunotropic effects of κ/ß-carrageenan isolated from the red algae Tichocarpus crinitus were studied, by orally administering it at 100 mg/kg/day to mice for 7 days. Serum levels of IFN-γ, IL-12, IL-1ß, and IL-4 were measured. Carrageenan's ability to influence development of LPS-induced inflammation was also assessed. Oral administration of κ/ß-carrageenan increased serum levels of all the studied cytokines at least twice in comparison to the intact mice, while intraperitoneal LPS injection at 1 mg/kg increased concentration of only the pro-inflammatory cytokines: IFN-γ, IL-12, and IL-1ß. Furthermore, κ/ß-carrageenan demonstrated a higher efficacy at inducing IFN-γ production than LPS. Previous 7-day-long oral carrageenan administration impaired development of LPS-induced inflammation: level of IL-1ß dropped below that found in intact mice, while IFN-γ and IL-12 concentrations were at least 40% lower than in mice with LPS-induced inflammation. Murine peritoneal macrophages were also affected by the oral administration of the κ/ß-carrageenan: their motility was increased, and morphology altered. In sum, we have demonstrated that κ/ß-carrageenan, when administered orally, is not only not immunologically inert, but at the dose of 100 mg/kg possesses pharmacologically exploitable effects.

Structural characteristics of carrageenans of red alga Mastocarpus pacificus from sea of Japan.

The sulfated polysaccharide from sterile alga Mastocarpus pacificus was investigated. Partial reductive hydrolysis and NMR spectroscopy showed that the extracted polysaccharides were only carrageenans. According to FT-IR- and NMR spectroscopy this polysaccharide was a hybrid kappa/iota-carrageenan with a predominance of kappa-type units. According to MALDI-TOFMS, oligosaccharide fragments obtained by mild acid hydrolysis had a polymerization degree of 1-9, while chains built up of galactose residues were up to 3. Tandem ESI mass spectrometry together with innovative 18O-labelling method showed that the polymer chain of the carrageenan included kappa-carrabiose, kappa-carratetraose, iota-carrabiose, hybrid kappa/iota oligosaccharide units and contained minor insertions of mu-carrageenan (the precursor of kappa-carrageenan). Parallel artificial membrane permeability assay shown that the studied carrageenan inhibited bile salts permeation through an artificial membrane imitating the gastrointestinal barrier by 50 % on average compared to negative control independent of incubation time. However, its action was less pronounced than the hindering ability of cholestyramine.

Mucoadhesive properties of sulphated polysaccharides carrageenans from red seaweed families Gigartinaceae and Tichocarpaceae.

The mucoadhesive properties of different types of carrageenan (kappa-, kappa/beta-, iota/kappa- and lambda-CRGs) isolated from red seaweed families Gigartinaceae and Tichocarpaceae collected on the Pacific coast were studied. We examined the interaction between CRGs and pig stomach mucin in dilute aqueous solutions using a set of methods. Measurements of the dynamic light scattering of mucin in the presence of CRG showed that the polysaccharides cause aggregation of mucin particles, as confirmed by microscopy data. The addition of CRGs to solutions of mucin resulted in the formation of a mixture that changed the charge of mucin, especially in the case of kappa- and kappa/beta-CRGs. The interaction between CRG and porcine gastric mucin in the presence of various additives confirmed that hydrogen bonds and electrostatic interactions are complemented when CRG and mucin are mixed in an aqueous medium, which is also confirmed by in vitro methods based on measurements of work of adhesion and shear stress. Kappa- and kappa/beta-CRGs that contain 3,6-anhydro-α-d-galactopyranose chains (DA) have high molecular weight and exhibit a high density of available hydrogen bonding groups able to interact more strongly with mucin glycoproteins.

Effects of Carrageenans on Biological Properties of Echinochrome.

Sea urchin pigment echinochrome A (Ech), a water-insoluble compound, is the active substance in the cardioprotective and antioxidant drug Histochrome® (PIBOC FEB RAS, Moscow, Russia). It has been established that Ech dissolves in aqueous solutions of carrageenans (CRGs). Herein, we describe the effects of different types of CRGs on some properties of Ech. Our results showed that CRGs significantly decreased the spermotoxicity of Ech, against the sea urchin S. intermedius sperm. Ech, as well as its complex with CRG, did not affect the division and development of early embryos of the sea urchin. Ech reduced reactive oxygen species production (ROS) in neutrophils, caused by CRG. The obtained complexes of these substances with pro- and anti-activating ROS formation properties illustrate the possibility of modulating the ROS induction, using these compounds. The CRGs stimulate the induction of anti-inflammatory IL-10 synthesis, whereas Ech inhibits this synthesis and increases the production of the pro-inflammatory cytokines IL-6 and TNFα. The inclusion of Ech, in the complex with the CRGs, decreases Ech's ability to induce the expression of pro-inflammatory cytokines, especially TNFα, and increases the induction of anti-inflammatory cytokine IL-10. Thus, CRGs modify the action of Ech, by decreasing its pro-inflammatory effect. Whereas, the Ech's protective action towards human epithelial HT-29 cells remains to be unaltered in the complex, with κ/ß-CRG, under stress conditions.

Liposomal Form of the Echinochrome-Carrageenan Complex.

Inclusion of drugs in liposomes offers the potential for localized and sustained delivery to mucosal surfaces. The inclusion of the carrageenan matrix with echinochrome A ((Ech)-the active substance of the drug Histochrome) in liposomes was studied. According to the spectral characteristics, Ech was not oxidized and retained stability after encapsulation in the liposomes and the lyophilization process. Loading the liposomes with negatively charged polysaccharide results in the increase in the zeta potential to more negative values (from -14.6 to -24.4 mV), that together with an increasing in the sizes of liposomes (from 125.6 ± 2.5 nm to 159.3 ± 5.8 nm) propose of the formation of the polymer coating on liposomes. The interactions of liposomes with porcine stomach mucin was determined by the DLS and SEM methods. The changes in the zeta-potential and size of the mucin particles were observed as the result of the interaction of liposomes with mucin. To evaluate the mucoadhesive properties of liposomes and the penetration of Ech in the mucosa, a fresh-frozen inner surface of the small intestine of a pig as a model of mucous tissue was used. Polysaccharide-coated liposomes exhibit very good mucoadhesive properties -50% of Ech remains on the mucosa.

Carrageenans-Sulfated Polysaccharides from Red Seaweeds as Matrices for the Inclusion of Echinochrome.

The possibility of using different types of carrageenans (CRG) as matrixes for incorporating of echinochrome A (Ech) was investigated. Ech interacts with carrageenans and is incorporated into the macromolecular structure of the polysaccharide. The inclusion of Ech in carrageenan matrices decreased its oxidative degradation and improved its solubility. The changing in the charge and morphology of CRGs during binding with Ech was observed. The rate of Ech release from CRG matrices depended on the structure of the used polysaccharide and the presence of specific ions. The gastroprotective effect of CRG/Ech complexes was investigated on the model of stomach ulcers induced by indomethacin in rats. Complexes of CRG/Ech exhibited significant gastroprotective activity that exceeded the activity of the reference drug Phosphalugel. The gastroprotective effect of the complexes can be associated with their protective layer on the surface of the mucous membrane of a stomach.

Structural analysis and cytokine-induced activity of gelling sulfated polysaccharide from the cystocarpic plants of Ahnfeltiopsis flabelliformis.

Gelling sulfated polysaccharide from the cystocarpic plants of Ahnfeltiopsis flabelliformis was studied. According to FT-IR and NMR spectroscopy data, the polysaccharide was found to be iota/kappa-carrageenan with iota- and kappa-type units in a 2:1 ratio containing beta-carrageenan units and minor amounts of nu- and mu-carrageenans. The HPLC and ESI MS/MS data of enzymatic hydrolysis products revealed that the main components of the polymer chain are iota-carrabiose, iota-carratetraose and hybrid tetra- and hexasaccharides consisting of kappa- and iota-units. Xylose was a substituent of a hydroxyl group at C-6 of 1,3-linked ß-d-galactose in the total polysaccharides. It was shown that the ability of carrageenans to increase the synthesis of cytokines depended on their molecular weight. The polysaccharide induced the synthesis of the anti-inflammatory cytokine IL-10, whereas oligosaccharides increased the synthesis of both pro- and anti-inflammatory cytokines at high concentrations.

Structural peculiarities of polysaccharide from sterile form of Far Eastern red alga Ahnfeltiopsis flabelliformis.

KCl-insoluble sulfated polysaccharide from sterile alga Ahnfeltiopsis flabelliformis was investigated. Partial reductive hydrolysis and NMR spectroscopy showed that the polysaccharide comprises disaccharide units of carrabiose only. According to FT-IR-, 1D, 2D NMR spectroscopies and mass-spectrometry this polysaccharide is kappa/beta-carrageenan with ratio of kappa- and beta-types units 3:1 and contains minor amounts of iota- and gamma-carrageenans (precursor of beta-carrageenan). In addition, ESIMS/MS data suggested that xylose (minor amount) is present in the polysaccharide as a substituent one of hydroxyl group of galactose. According to aPTT and PT assays the studied carrageenan affected mostly intrinsic pathway of coagulation, while it effect on the extrinsic pathway is absent.