Polysaccharides

<p>Polyguluronic acid is produced from alginates by partial hydrolysis and chromatography of brown algae such as Laminaria digitata, Ascophyllum nodosum and Fucus spp.<br>The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.MW is ca 6000 - 8000Da.poly-M levels are ca 3%</p>

<p>In addition to the β-glucans from cereals, another group of β-glucans are found in the cell walls of yeast (Saccharomyces cerevisiae), bacteria and fungi, with significantly differing physicochemical properties dependent on source. Typically these β-glucans form a linear backbone with 1,3 β-glycosidic bonds but vary with respect to molecular mass, solubility, viscosity, branching structure, and gelation properties, causing diverse physiological effects in animals.  They are structural components in the cell walls of Saccharomyces cerevisiae and to provide stability, they have a few b-1,6 branch points that lock into other cell wall components (1 in 5 glucose residues). So in any extraction you get a few 1,6 linked glucose residues ~5%.<br>The yeast and fungal β-glucans have been investigated for their ability to modulate the immune system. They are also used in various nutraceutical and cosmetic products, as texturing agents, and as fibre supplements. Their detailed molecular structures are key to the physical properties that they exhibit, such as water solubility, viscosity, gelation properties and physiological functions.<br>The image was kindly provided by Dr. Chris Lawson.</p>

<p>Laminaran is a polysaccharide that co-occurs with fucoidan and alginate in brown seaweeds such as Laminaria digitata, Laminaria cloustoni, Eisenia bicyclis and Thallus laminariae. It is a β-1,3-linked glucan which it is claimed stimulates the immune system in mammals and fish.<br>The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.</p>

<p>Gycosaminoglycan in many organs; joint lubricant and shock absorber</p>

<p>The sodium salt of hyaluronic acid is a glycosaminoglycan found in many organs, where it functions as a joint lubricant and shock absorber. It is obtained principally from synovial fluid, vitreous humor of the eye, umbilical tissue and cocks comb. The chemical structure of hyaluronic is a disaccharide repeat of β-(1,3) glucuronic acid and β-(1,4) N-acetyl glucosamine.</p>

<p>Gycosaminoglycan in many organs; joint lubricant and shock absorber.  Made by a bacterial, Streptococcus fermentation.</p>

<p>A fucan sulphate found in brown marine algae (Phaeophyta-typically Fucus vesiculotus, Ascophyllum nodosum (illustrated), Alaria and Cladosiphon) and has been shown to have anticoagulant activity. The main constituents are α-1,4 and α-1,2 linked L-fucose sulphates although galactose also occurs and there are many variations of the basic structure found in different species of Phaeophyta.Molecular weight cut off at 300kDa.The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.</p>

<p>Gycosaminoglycan in many organs; joint lubricant and shock absorber</p>

<p>Dextran sulphate is a dextran derivative whose ulcer (colitis) -causing properties were first reported in hamsters and extrapolated a few years later to mice and rats. The exact mechanisms through which dextran sulphate induces intestinal inflammation are unclear but may be the result of direct damage of the monolayer of epithelial cells in the colon, leading to the crossing of intestinal contents (for e.g. commensal bacteria and their products) into underlying tissue and therefore induction of inflammation.  The dextran sulphate sodium induced ulceration model in laboratory animals has some advantages, when compared to other animal models of colitis, due to its simplicity and similarities to human inflammatory bowel disease.</p>

<p>Please enquire for more information about Fucoidan - Ascophyllum nodosum including the price, delivery time and more detailed product information at the technical inquiry form on this page</p>

<p>Arabinoxylans consist of α-L-arabinofuranose residues attached as branch-points to β-(1,4)-linked D-xylopyranose main chains. These may be 2- or 3-substituted or 2- and 3- di-substituted. The arabinose residues may also be linked to other groups attached such as glucuronic acid residues, ferulic acid cross links and acetyl groups. Arabinoxylans generally consist of between 1500 - 5000 residues.</p>

<p>Guar gum is obtained from the seed of the legume Cyamopsis tetragonolobus, an annual plant that grows mainly in semi-arid regions of India. The structure of the polysaccharide consists of a main chain of (1,4)-linked β-D-mannopyranosyl units with single α-D-galactopyranosyl units linked (1,6) on average to every second main chain unit. Guar has a high viscosity in aqueous solution, shows marked pseudoplastic behaviour and forms synergistic gels in the presence of other gums such as carrageenan and xanthan gum.</p>

<p>Sodium salt of a polysaccharide obtained from the brown seaweeds (e.g. Laminaria hyperborea, Fucus vesiculosus, Ascophyllum nodosum). The chemical structure consists of blocks of (1,4) linked-β-D-polymannuronic acid (poly M), (1,4) linked-α-L-polyguluronic acid (poly G) and alternating blocks of the two uronic acids (poly MG). Alginates form strong gels with divalent metal cations and the egg box model has been used to describe this form of gelation. The main use for alginate is in textile printing as a thickener in the printing of cottons with reactive dyes. In the food industry it is used as a thickener and gelling agent.  Recently, it has been shown that ternary mixtures of Konjac glucomannan, Xanthan gum and Sodium alginate can form a non-covalently linked complex which exhibits enhanced rheological properties of value in, for example, functional foods.<br>The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.</p>

<p>Cellulose with a particle size of 20μm is an industrial biomass material that has various applications. It is commonly used in the production of paper, textiles, and biofuels. Cellulose is a complex carbohydrate that provides structural support to plant cell walls. It can also be used as an excipient in pharmaceutical formulations, such as in the production of tablets.</p>

<p>Cellulose is a linear polysaccharide of β 1-4 linked glucose residues. The polysaccharide chains are bundled as microfibrils in cell walls and provide the essential structural components within growing plants. Each microfibril exhibits a high degree of three-dimensional internal bonding resulting in a crystalline structure that is insoluble in water, resistant to reagents and very strong.</p>

<p>Starch is an energy storing polysaccharide produced by higher plants and some algae. Pure starch is a white, tasteless and odorless powder that is insoluble in cold water or alcohol. It consists of two types of polysaccharide: the linear and helical amylose (α-1,4-linked glucose) and the branched amylopectin (α-1,4 and α-1,6-linked glucose). Depending on the plant, starch generally contains 20 to 25% amylose and 75 to 80% amylopectin by weight.</p>

<p>In water, hydroxypropyl cellulose forms liquid crystals with many mesophases depending on concentration. These mesophases include isotropic, anisotropic, nematic and cholesteric, the latter resulting in many colors such as violet, green and red. Pharmaceutical applications include treatments for medical conditions such as dry eye syndrome (keratoconjunctivitis sicca), recurrent corneal erosions, decreased corneal sensitivity, exposure and neuroparalytic keratitis. It is also used as a binder in tablets. Hydroxypropylcellulose is also used as a thickener, a binder and emulsion stabiliser in foods with E number E463.  HPC is used as a support matrix for DNA separations by capillary and microchip electrophoresis.</p>

<p>Pectins are regarded as linear chains of α-1,4-linked D-galacturonic acid, a homogalacturonan (pectic acid). In the products of commerce, the degree of methylation has a vital influence on the properties of pectin, especially the solubility and gel forming characteristics.</p>

<p>Sugar beet arabinan consists of a 1,5 α-linked arabinose backbone to which 1,3 α-linked (and possibly some 1,2 α-linked) L-arabinofuranosyl residues are attached. Approximately 60% of the main-chain arabinofuranosyl residues are substituted by single 1,3-linked arabinofuranosyl groups. The reducing terminal arabinosyl residue is attached through rhamnose to fragments of the rhamnogalacturonan backbone of the native pectin molecule.</p>

<p>Dextran sulphate is a dextran derivative whose ulcer (colitis) -causing properties were first reported in hamsters and extrapolated a few years later to mice and rats. The exact mechanisms through which dextran sulphate induces intestinal inflammation are unclear but may be the result of direct damage of the monolayer of epithelial cells in the colon, leading to the crossing of intestinal contents (for e.g. commensal bacteria and their products) into underlying tissue and therefore induction of inflammation.  The dextran sulphate sodium induced ulceration model in laboratory animals has some advantages, when compared to other animal models of colitis, due to its simplicity and similarities to human inflammatory bowel disease.</p>