Polissacáridos

Polyguluronic acid is produced from alginates by partial hydrolysis and chromatography of brown algae such as Laminaria digitata, Ascophyllum nodosum and Fucus spp.
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%

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.
The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.

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.

Propylene glycol alginate is a reaction product of propylene oxide and alginic acid. At the 49th JECFA meeting (1997) it was resolved that the total dietary propylene glycol intake from all sources should be allocated an ADI of 0-25 mg/kg.  Applications include as a stabiliser in beer foam due to electrostatic interaction between carboxyl groups on the glycol alginate molecules and amino groups on the peptides in the bubble wall and in ice cream by emulsifying the fat.Esterification is greater then 80%Viscosity (1% aq solution): 200-300 mpa.s

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.

Glycogen is a highly branched polysaccharide of glucose that serves as a form of energy storage in animals and fungi. It is the main storage form of glucose in the body.  In humans, glycogen is made and stored primarily in liver and muscle cells and functions as the second most important energy storage molecule to fat which is held in adipose tissue. Glycogen is analogous to starch and has a structure similar to amylopectin, but is more extensively branched and compact than starch. It occurs as granules in the cytosol/cytoplasm in many cell types, and plays an important role in the glucose cycle.

Applications Isomaltopentaose, is an isomalto-oligosaccharides (IMO) compound, used as functional food ingredients.
References Hu, Y., et al.: Lett. App. Microbio., 57, 108 (2013);

Applications Isomaltotetraose, can be used for immunizication of hybridoma antibodies. the use of synthetic glycolipids as antigens enables one to study the gene control of antibody responses to glycolipids and to investigate the combining-site specificities of antibodies to a single antigenic determinant.
References Lai, E., et al.: Mol. Immunology, 22(9), 1021 (1985); Chen, H. T., et al.: Mol. Immunology, 24(4), 333 (1987);

Applications 2-Amino-2-deoxygalacturonic acid was a component of the lipopolysaccharide from P. aeruginosa NCTC 8505 and probably occurs in the region of polysaccharide responsible for O-antigenic specificity.
References Wilkinson, S.G., et al.: Biochem. J., 149, 783 (1975),

Viscoelastic polymer; excipient; food additive

Fluorescein isothiocyanate dextran is a fluorescent derivative of a dextran fraction with an average molecular weight of approximately 4000. It is supplied as a yellow powder which is readily soluble in water.

Pectin is a highly complex polysaccharide matrix that is found in the primary walls of dicotyledenous and monocotyledenous plants and gymnosperms, including potato. A key fragment of this complex is rhamnogalacturonan I, containing a backbone of the repeating disaccharide  [-4)-α-D-GalpA-(1,2)-α-L-Rhap-(1,]. Several applications for RG1 have been described including drug targeting to the colon via the oral administration route for local treatment of e.g. inflammatory bowel disease and colon cancer.  This has several advantages such as needle-free administration and low infection risk. In the gastro-intestinal tract RG-I is only degraded by the action of the colonic microflora. High purity rhamnogalacturonan I is also used in research, biochemical enzyme assays and in vitro diagnostic analysis.

Ulvans are structural polysaccharides present in the cell walls of green algae such as Ulva armoricana, Ulva rotondata, Ulva rigida, Ulva lacterca and Ulva pertusa. They are highly sulphated and contain rhamnose 3-sulphate, xylose, xylose 2-sulphate, glucuronic acid and iduronic acid residues. Ulvan has several potentially valuable functionalities such as gel formation for agricultural and food applications and possible anticoagulant, antioxidant, antihyperlipidemic and antitumoral activities for pharmaceutical applications.
The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.

The extracellular polysaccharide produced by Arthrobacter stabilis NRRL B-3225 contains D-glucose, D-galactose, pyruvic acid, O-succinyl, and O-acetyl in the approximate molar ratio of 6:3:1:1:1.5. Succinyl is linked as its half-ester, making it readily removable. The viscosity of aqueous, salt-free solutions of both native and deacylated polymer is relatively low, but atypical of anionic polysaccharides, increases rapidly in the presence of salts, acids, or alkali.

DEAE-Dextran hydrochloride (DEAE-D) is a positively-charged dextran derivative that can be used for vaccine production, gene therapy, protein stabilisation, dyslipidemia prevention, as flocculating agent, and many other applications. DEAE-D is also used for transfecting animal cells with foreign DNA.  DEAE-Sepharose, DEAE-650 and DEAE-Sephadex are commonly used in chromatography for the separation of biological molecules such as proteins and carbohydrates.

Kappa-Carrageenan is a gelling sulphated galactan extracted from red seaweed (typically Mastocarpus stellata and Chondrus crispus). The structure of all carrageenans consists of a strictly alternating masked repeating unit of 1,3-linked α-D-galactose and 1,4-linked β-D-galactose. The α-linked galactose occurs as α-3-6-anhydro unit and the β-linked sugar occurs as the 4-sulphate.
The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.

Please enquire for more information about (Hydroxypropyl)methyl cellulose, viscosity 5 cP 80%-120%, 2% aqueous solution including the price, delivery time and more detailed product information at the technical inquiry form on this page

Complex glucan (a 1-6) from Leuconostoc spp.; extender in blood transfusions

Applications Verbascose (CAS# 546-62-3) is an α-galactooligosaccharide with immunomodulatory activity in mouse macrophage RAW264.7 cells.
References Dai, Z.; et al.: J. Agric. Food. Chem., 66, 9070 (2018);

Xylan is the most abundant noncellulosic polysaccharide present in both hardwoods and annual plants. Xylan is found mainly in the secondary cell wall as part of the hemicellulose fraction and is considered to form an interface between lignin and other polysaccharides. In their simplest forms, xylans are linear homopolymers of β-1,4-xylose residues but can also form complex heterogenous and polydispersed glycans.

A fucan sulphate found in brown marine algae (Phaeophyta-typically Fucus serratus, Ascophyllum nodosum (illustrated), Laminaria japonica and Macrocystis pyrifyra) 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.
The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.

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. 
MW is in the range of 40,000Da

Chitin forms the tough fibrous exoskeletons of insects, crustaceans and other arthropods, and, in addition to its presence in some fungi, it occurs in at least one alga. The structure of chitin is similar to that of cellulose but with glucose replaced with N-acetyl-D-glucosaminyl units linked β-D-(1,4) in a linear chain. Chitin is normally produced from the shells of lobster, crab or shrimp.

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.

A fucan sulphate found in brown marine algae (Phaeophyta-typically Fucus serratus, Ascophyllum nodosum, Laminaria digitata (illustrated) and Macrocystis pyrifyra) 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.
The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.

Lichenin, the poly β-D-Glucan of Cetraria islandica (Iceland moss), is found by enzymic degradation to differ in fine structure from the poly β-D-glucans of cereal grains. Thus, the basic structure of lichenin is a tetrameric unit in which two adjacent 1,4 linkages alternate with an isolated 1,3 linkage; occasionally four consecutive monomers are linked by 1,4 bonds. The immunomodulatory activity of isolichenan was tested in in vitro phagocytosis and anti-complementary assays, and proved to be active in both cases.
The image was kindly provided by Prof Mike Guiry from Cork who runs ‘The Seaweed Site’.

Glycogen is a highly branched polysaccharide of glucose that serves as a form of energy storage in animals and fungi. It is the main storage form of glucose in the body.  In humans, glycogen is made and stored primarily in liver and muscle cells and functions as the second most important energy storage molecule to fat which is held in adipose tissue. Glycogen is analogous to starch and has a structure similar to amylopectin, but is more extensively branched and compact than starch. It occurs as granules in the cytosol/cytoplasm in many cell types, and plays an important role in the glucose cycle.

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.

Gum karaya is exuded from Sterculia urens, a bushy tree found in dry regions of North India. Due to its extensive swelling capacity in water it is used as a laxative and as a denture adhesive. The structure consists of D-galactose, D-glucuronic acid and L-rhamnose but the detailed molecular structure is still incompletely known.

Dextran is α-(1,6)-linked α-D-glucan produced by fermentation of Leuconostoc mesenteroides via the action of the enzyme dextransucrase on sucrose. The main use for native dextran is as a blood plasma extender in blood transfusions. A complex of iron with dextran, known as iron dextran, is used as a source of iron to baby piglets which are often anaemic at birth.

Water thickener; rheological control additive; has industrial appplications

Larch arabinogalactan is extracted from the heartwood of the western larch Larix occidentalis. This compound has a backbone of 1,3-linked β-D-galactopyranosyl units each of which contains a side chain at position C-6. Arabinogalactans are used as emulsifiers, stabilizers and binders in the food, pharmaceutical and cosmetic industries, as low viscosity dietary fibres and as a prebiotic fibres.

Oat β-glucans are water-soluble β-glucans derived from the endosperm of oat kernels, which contain β-1,3 and β-1,4 linkages. They are known for cholesterol lowering and hypoglycemic properties, as well as their use in various cosmetic applications. Recent research has shown their potential application in immunomodulation and wound healing.

Dermatan sulphate is a glycosaminoglycan found in skin, blood vessels, heart valves, tendons, aorta, spleen and brain and is usually isolated from pig skin or beef lung tissue. The disaccharide repeat unit is composed of L-iduronic acid and N-acetyl-galactosamine-4-sulphate linked β-(1,3) and β-(1,4). There are also small amounts of D-glucuronic acid.

Methyl cellulose is a water-soluble polymer that is used as a binder or thickener in pharmaceutical, food, and ceramic processing applications. Methylcellulose has an unusual lower critical solution temperature (LCST) between 40 °C and 50 °C. At temperatures below the LCST it is readily soluble in water; above the LCST it is not soluble, which has a paradoxical effect that heating a saturated solution of methylcellulose will turn it solid, because methylcellulose will precipitate out. The temperature at which this occurs depends on DS-value, with higher DS-values giving lower solubility and lower precipitation temperatures because the polar hydroxyl groups are masked.

Dextran is α-(1,6)-linked α-D-glucan with α-(1,3)-linked glucose branch points produced by fermentation of Leuconostoc mesenteroides via the action of the enzyme dextransucrase on sucrose.  The main use for native dextran is as an extender in blood transfusions and products having a range of sharp cut-off molecular weights are produced commercially for this and other applications. A complex of iron with dextran, known as iron dextran, is used as a source of iron for baby piglets which are often anaemic at birth.

Carboxymethyl curdlan is widely used in the preparation of nanoparticles for biomedical applications. Following the synthesis of superparamagnetic iron oxide nanoparticles (SPIN) capped with carboxymethyl curdlan for use in cellular and in vivo imaging applications, the stability and dispersibility of SPIN in water were greatly improved with the introduction of the carboxymethyl curdlan moiety. Recently, a green and simple route was proposed to synthesize Ag nanoparticles using carboxymethylcurdlan under UV irradiation.

Konjac glucomannan is an acetylated (1,4)-β-D-glucomannan obtained from the tubers of Amorphophallus konjac or Konnyaku root. It is widely used in foods, pharmaceuticals paints and explosives. 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.

The main cell-wall components of baker’s yeast (Saccharomyces cerevisiae) as well as β-glucan are mannans with an α-1,6 mannose backbone and α-1,2 and α-1,3 mannose branches.
The image was kindly provided by Dr. Chris Lawson.