Properties of cell wall polysaccharides of raw nectarine fruits after treatment under conditions that modulate gastric digestion.

The results of the study of the physicochemical properties of the high-molecular-weight soluble and insoluble components of nectarine cell walls obtained by fruit treatment under conditions that modulate of gastric digestion are presented. Homogenized nectarine fruits were sequentially treated by natural saliva and simulated gastric fluid (SGF) at pH 1.8 and 3.0. The isolated polysaccharides were compared with polysaccharides obtained by sequential extraction of nectarine fruit with cold, hot, and acidified water, solutions of ammonium oxalate and sodium carbonate. As a result, high-molecular-weight water-soluble pectic polysaccharides, weakly bound in the cell wall, were dissolved in the simulated gastric fluid, regardless of pH. Homogalacturonan (HG) and rhamnogalacturonan-I (RG-I) were identified in all pectins. It was shown that their quantity and ability to form highly viscous solutions determine high values of the rheological characteristics of the nectarine mixture formed under simulated gastric conditions. The modifications occurring with the insoluble components under the influence of acidity of SGF were importance. They determined difference in the physicochemical properties of both the insoluble fibres and the nectarine mixtures.

[Senile atopic dermatitis - current vision and unresolved issues.]

Atopic dermatitis (AD) is one of the most common dermatoses with a complex multifactorial pathogenesis including genetic predisposition, epidermal dysfunction, immune dysregulation, and disruption of the skin microbial landscape. The clinical picture of AD is characterized by age-related dynamics with changes in the morphology and localization of the skin rash; there are infantile, childhood, and adult stages of dermatosis. In recent years, the term «senile AD¼ has also been discussed for patients aged 60 and older. This form of the disease is supposed to have a number of features of pathogenesis and clinical manifestations due to age-related skin involution and aging of the body as a whole, which requires correction of traditional approaches to diagnosis and therapy of the disease. The presented review systematizes the data on epidemiology, pathogenesis, clinical manifestations and treatment of AD in elderly and senile patients. The analysis of the literature revealed that the epidemiological data on the incidence of AD in elderly and senile patients are solitary and contradictory. The peculiarities of the pathogenesis of this form of dermatosis are synergistic changes in the skin barrier and immune function, which leads to a more severe course of dermatosis. The contribution to the pathogenesis and character of the course of AD of somatic diseases characteristic of the aged over 60 and the therapy patients receive for these comorbidities, as well as the peculiarities of the lifestyle of the elderly and irrational skin care are discussed. There are few data on the specifics of treatment of elderly and senile patients with AD; in severe forms of dermatosis, low-dose dupilumab and methotrexate are suggested as the systemic therapy of choice.

Application of Pectin from Aloe arborescens Mill. to the Cryopreservation of Human Leukocyte Cell Suspensions.

BACKGROUND: The molecular weight (MW) of pectic polysaccharide АА3 equal to 150 kDa and its structure suggest that it has a non-permeating protector action. OBJECTIVE: To study the ability of low methylesterified galacturonan АА3, extracted from Aloe arborescens Mill., to influence the cryoprotective properties of the refrigerant in the cryopreservation of leukocytes (-20°Ð¡, -80°Ð¡). METHODS: Pectic polysaccharide АА3 was extracted from fresh leaves using a 0.7% (w/w) solution of ammonium oxalate. The cryoscopic method was used to study its ability in different concentrations (0.1-1% w/v) in a mixture with glycerol to change the osmolarity and freezing temperature of the venous blood. Venous blood was protected with a comprehensive cryopreservative solution (3.5 % glycerol + 0.1 % pectic polysaccharide АА3) and stored at -20°C and -80°C for 1 and 7 days. RESULT: The cryoprotective properties of glycerol solution (3.5%) containing AA3 at 0.1 to 1.0% led to a decrease in the osmolarity of venous blood and accelerated the process of water freezing. So, these solutions act as nucleators. A solution of AA3 (0.1%) and glycerol (3.5%) improves the morphological preservation of granulocytes, resistance of cell membranes to eosin and phagocytic activity of neutrophils after -20°C storage for 7 days. CONCLUSIONS: The addition to glycerol solution (3.5%) of pectic polysaccharide АА3 (0.1%) may facilitate the formation of a three-dimensional network of intermolecular hydrogen bonds between the functional groups of pectin (mainly carboxyl) and hydroxyl groups of polyhydric alcohol. Better linkage of cellular water molecules in the biological specimen may improve cryoprotection.

Structural, rheological and antioxidant properties of pectins from Equisetum arvense L. and Equisetum sylvaticum L.

The pectins were isolated from sterile stems of E. arvense (EA, yield 5.9%) and E. sylvaticum (ES, yield 4.8%) (Equisetaceae) using ammonium oxalate extraction after preliminary treatment with dilute HCl (рH 4.0). The pectins possessed high molecular weight (Mw, 340-360 kDa), high GalA content (ca. 85%), low degrees of methyl-esterification (14-16%) and acetylation (3-8%). NMR analysis indicated extensive regions of partially methyl-etherified and 3-O-acetylated HG and minor regions of low branched RG in the fragment isolated after hydrolysis of pectin EA by pectinase. Pectin EA produced a higher viscosity solution, formed a stronger and more rigid ionotropic hydrogel than pectin ES. The pectins scavenged DPPH and hydroxyl radicals, but not the superoxide radical and hydrogen peroxide. Phenolic compounds (0.11 and 0.23%) associated with polysaccharide moieties were apparently responsible for the differences in the anti-DPPH scavenging activity of pectins EA and ES (63 and 49%). The findings suggested that pectin from E. arvense should be more perspective than pectin from E. sylvaticum on their use as components of wound healing remedies.

Review of hypothesized mechanism of action of beta-glucan’s on cancer cells / Монголын Анагаах Ухаан

@#The human immune system has a remarkable ability to distinguish between the body’s own cells, recognized as “self” and foreign cells, as “nonself”, to mediate the immune responses. Mushroom β-glucans are a large group of macromolecules that are not naturally synthesized inside the human body, so these compounds are recognized as non-self-molecules, which activate the immunity. Mushroom polysaccharides or β-glucans are thought to provide their anti-tumor action primarily through the activation of the immune response of the host organism. In most cases mushroom polysaccharides do not directly affect tumor cells. </br> Certain β-glucans from medicinal mushrooms appear to activate cell-mediated and humoral immunity via activation of different immune cells, leading to elimination of tumor cells or pathogens. The activated macrophages (containing β-glucans) preferentially attack dead cells and intracellular pathogens. These macrophages also produce cytokines that prime natural killer cells and T lymphocytes, both of which are cytotoxic to tumor cells, via different mechanisms. Natural killer cells secrete chemical substances that destroy tumor cells by bursting cell membranes. Neutrophils effectively destroy targeted cells by cell mediated phagocytosis. In this review were described the hypothesized mechanism of action for fungal β-glucans against cancer cells.

Application of Pectin From Rauvolfia serpentina (L.) Benth to the Cryopreservation of Human Leucocyte Cell Suspensions.

　　BACKGROUND: Due to their valuable medicinal properties and high physiological activity, plant polysaccharides are currently being extensively studied. OBJECTIVE: The present study aims to investigate rauwolfian (pectin for Rauvolfia serpentina) supplementation on human leukocytes cryopreservation. We determined the сharacteristics of leukocytes undergoing freezing with pectin at different temperatures. METHODS: Donor leukocytes were frozen under the protection of comprehensive cryoprotectant solution and stored in electrical freezers (-20C, -40C, -80C). RESULT: A regular decrease of all values starting from a higher temperature (-20С) through to the lower temperature (-80С) was identified. The study showed that pectin rauwolfian stimulated both the oxygen-independent and the oxygen-dependent killer response. We also found that the oxygen-dependent neutrophil killer effect was reduced as the storage temperature was lowered. It was determined that the LPO levels in the cells with added pectin-containing solutions remained the same before freezing, while their antioxidant activity positively increased, which is beneficial for neutrophils for their further freezing to -20C, -40C and -80C. CONCLUSIONS: The results of the study make it possible to assume that rauwolfian, a pectin extracted from Rauvolfia serpentina, has an exocellular protectant effect as part of cryopreservative solution on human white blood cells stored at different low temperatures. The versatility of the substance is probably due to the degree of the macromolecule branching, in particular, the structure of carbohydrate side chains, which contain a large number of hydroxyl groups.

[Comparative Analysis of Spectrophotometric Methods of the Protein Measurement in the Pectic Polysaccharide Samples].

For the assay to reliability of determination of the protein content in the pectic polysaccharide samples by absorbance in the ultraviolet and visible regions of the spectrum a comparison of the eleven techniques called Flores, Lovry, Bradford, Sedmak, Rueman (ninhydrin reaction) methods, the method of ultraviolet spectrophotometry, the method Benedict's reagent, the method Nessler's reagent, the method with amide black, the bicinchoninic reagent and the biuret method was carried out. The data obtained show that insufficient sensitivity of the seven methods from the listed techniques doesn't allow their usage for determination of protein content in pectic polysaccharide samples. But the Lowry, Bradford, Sedmak methods, and the method Nessler's reagent may be used for determination of protein content in pectic polysaccharide samples, and the Bradford method is advisable for protein contaminants content determination in pectic polysaccharide samples in case protein content is less than 15%, and the Lowry method--for samples is more than 15%.

[Binding of human serum low-density lipoprotein cholesterol in vitro by sulfated pectin derivatives].

The ability to bind human serum LDL-C in vitro by the native pectins is lower than that of their sulfation derivatives. The number of sulfate groups and molecular weight of the sulfated derivatives are assumed to be crucial factors. The sulfated derivatives of pectin with molecular weight above 200 kDa containing 45 wt % sulfate groups possess the highest ability to bind atherogenic lipids, the lowest activity was estimated for the derivatives with molecular weight below 50 kDa containing 5 wt % of sulfate groups.

Synthesis of sulfated pectins and their anticoagulant activity.

The following pectins were sulfated: bergenan BC (the pectin of Bergenia crassifolia L), lemnan LM (the pectin of Lemna minor L), and galacturonan as a backbone of pectins. Pyridine monomethyl sulfate, pyridine sulfotrioxide, and chlorosulfonic acid were used as reagents for sulfation. Chlorosulfonic acid proved to be the optimal reagent for sulfation of galacturonan and other pectins. Galacturonan and pectin derivatives with different degrees of sulfation were synthesized and their anticoagulant activities were shown to depend on the quantity of sulfate groups in the pectin macromolecules.

[Structural study of bergenan, a pectin from Bergenia crassifolia].

A pectin polysaccharide named bergenan was isolated from the freshly collected leaves of the leather bergenia Bergenia crassifolia by extraction with an aqueous solution of ammonium oxalate. The main component of its carbohydrate chain was shown to be the residues of D-galacturonic acid (about 80%). In addition, the polysaccharide contains residues of galactose, arabinose, and rhamnose; their total content is less than 15%. It was shown that the bergenan samples from bergenia leaves collected at different vegetation periods (from July to September) do not substantially differ either in monosaccharide composition or in the viscosity of aqueous solutions they form. The results of enzymatic hydrolysis by alpha-1,4-galacturonase (pectinase), partial acidic hydrolysis, NMR spectroscopy, and methylation with subsequent analysis of the results by GC-MS indicate that the bergenan macromolecule contains the regions of a linear alpha--1,4-D-galactopyranosyluronan and rhamnogalacturonan-I (RG-1). Galacturonan responds for a greater part of the macromolecule. A considerable amount of its constituent galacturonic acid residues are present as methyl esters. The side chains in RG-I are attached to the rhamnopyranose residues of the main carbohydrate chain by 1,4-link and are composed of the residues of terminal arabinofuranose and galactopyranose, 1,5-linked (-arabinofuranose, and 1,4-and 1,6-linked beta-galactopyranose. The branching points of the side chains of the RG-I molecule are 3,4- and 3,6-di-O-substituted galactose residues.

Branching of the galacturonan backbone of comaruman, a pectin from the marsh cinquefoil Comarum palustre L.

Galacturonan, the main constituent of the backbone (core) of the comaruman macromolecule, a pectin from the marsh cinquefoil Comarum palustre L., was obtained on partial acid hydrolysis of the pectin. Using atomic force microscopy and methylation analysis of the galacturonan, the backbone of the comaruman macromolecule was shown to contain branches as side chains consisting of alpha-1,4-linked residues of D-galactopyranosyl uronic acid attached to the 2- and 3-positions of the galacturonic acid residues of the core, in addition to linear regions of alpha-1,4-D-galacturonan. A few side chains appear to attach to 2,3-positions of the D-galacturonic acid residues.

Immunostimulating activity of pectic polysaccharide from Bergenia crassifolia (L.) Fritsch.

The pectic polysaccharide named bergenan BC was obtained using extraction of the green leaves of Siberian tea Bergenia crassifolia (L.) Fritsch. by an aqueous ammonium oxalate. The polysaccharide obtained was proved to comprise mainly d-galacturonic acid, galactose, rhamnose, arabinose and glucose residues and appeared to be pectin. Delayed type hypersensitivity (DTH) reaction to aggregated ovalbumin (agOVA) was found to increase in mice that received bergenan solution (2 mg/mL) for 3 weeks. Bergenan BC was observed to enhance the uptake capacity of human neutrophils at a concentration 100 microg/mL and to stimulate the generation of oxygen radicals by mouse peritoneal macrophages in vitro. Bergenan BC was found to increase the spontaneous adhesion of peritoneal leukocytes and failed to influence adhesion stimulated by PMA or adhesion of peritoneal leukocytes incubated in the presence of 5 mm EDTA. Bergenan failed to show cytotoxic action. The viability of peritoneal leukocytes was estimated to be equal to 91% +/- 8% and 90% +/- 7%% in the control and in the pectin solution at a concentration of 1 mg/mL.Thus, bergenan was shown to possess immunostimulating activity in relation to DTH response in vivo and phagocytic activity in vitro.

[The isolation, preliminary study of structure and physiological activity of water-soluble polysaccharides from squeezed berries of Snowball tree Viburnum opulus]. / Vydelenie i predvaritel'noe issledovanie stroeniia i fiziologicheskoi aktivnosti vodorastvorimykh polisakharidov iz shrota iagod Kaliny obyknovennoi Viburnum opulus.

Water-soluble polysaccharide fractions VO1-VO4 were isolated from the squeezed berries of snowball tree (Viburnum opulus) by successive extraction with water at various temperatures and pH and with aqueous solutions of ammonium oxalate. These fractions were purified by ion-exchange chromatography on DEAE cellulose, and the homogeneity of the purified polysaccharides was determined by gel filtration on Sephacryl S-500. Acidic polysaccharides close to pectins in their sugar composition were found in all the extracts (fractions VO1-1, VO2-1, VO3-2, and VO4-2). Residues of galacturonic acid, galactose, arabinose, and (to a lesser extent) rhamnose are their main constituents. Neutral polysaccharides composed mainly of galactose and mannose residues were additionally found in fractions extracted with acidified water (pH 4.0) and with aqueous ammonium oxalate solutions. Partial acidic hydrolysis and digestion with pectinase of acidic polysaccharides indicated that their carbohydrate backbone consists of alpha-1,4-linked residues of D-galacturonic acid. NMR spectra of acidic polysaccharides (fractions VO3-2 and VO3-3) confirmed this and demonstrated that their side oligosaccharide chains are composed of beta-1,4-linked galactopyranose residues and of terminal and 2,5- and 3,5-substituted residues of alpha-arabinofuranose at a Gal: Ara ratio of 3:1. Some polysaccharides from V. opulus were found to possess an immunostimulating activity: they enhance phagocytosis, in particular, the phagocytic index and the secretion of lysosomal enzymes with peritoneal macrophages. Calcium ions were found to be necessary for the appearance of the stimulating effect of acidic polysaccharides from V. opulus.

[Structure and physiological activity of lemnan, Lemna minor L. pectin]. / Strukturnoe issledovanie i fiziologicheskaia aktivnost' lemnana, pektina iz Lemna minor L..

A pectic polysaccharide, lemnan, was isolated from freshly collected duckweed Lemna minor L. Its sugar chain was shown to be mainly composed of the residues of D-galacturonic acid (64%), galactose, arabinose, xylose, and D-apiose, a branched chain sugar. The high content of D-apiose (25%) indicated that lemnan is an apiogalacturonan type pectin similar to zosteran, a pectic polysaccharide from a sea phanerogam of the Zosteraceae family. The results of partial acidic hydrolysis, pectinase digestion, and NMR studies of lemnan demonstrated that its macromolecule contains regions of the linear alpha-1,4-D-galacturonan and branched apiogalacturonan. The side chains of apiogalacturonan were found to be formed of single and 1,5-linked residues of D-apiofuranose attached to 2- and 3-positions of the D-galacturonic acid residues of the apiogalacturonan backbone. Lemnan was shown to exhibit an immunomodulatory effect by activating the system of phagocytosis.