Alginate linear polysaccharide

The same group investigated the separation of fluorescently labled sugars by different CDs as well as linear polysaccharides (dextrin 10, dextran, laminarin, and alginic acid) and oligosaccharides in the presence of borate... 

Ficoll is a synthetic polymer of sucrose. Alginate is a linear polysaccharide from marine organisms consisting of D-mannuronic and L-guluronic acid residues. Alginate has the important property that it forms a gel in the presence of bivalent cations, like Ca ". ... 

Alginate is also a naturally occurring linear polysaccharide extracted from seaweed, algae, and bacteria. The fundamental chemical structure of alginate is composed of (l )-b-o-mannuronic acid... 

Chitosan is a linear polysaccharide, which is typically used to form coating layers on preformed systems. For example, probiotics encapsulated in an alginate matrix, and further coated with a layer of chitosan, are characterized by an improved protection in the gastrointestinal tract, which enable them to reach with high viability the colon. The main disadvantage of chitosan is an observed inhibitory effect on LAB. 

On structural basis, polysaccharides are classified as linear, short branched, and branch on branch. Amylose, cellulose, pectin, alginates are some linear polysaccharides. Short-branched polysaccharides are guar gum, locust bean gum, and xanthan gum. Polysaccharides with branch-on-branch structure are amylopectin, gum arabic, and arabinoxylan. 

Alginates, which are also called alginic acids, are anionic linear polysaccharides secreted by brown seaweed and marine algae, including Laminaria hyperborea, Ascophyllum nodosum and Macrocystis pyrifera [3]. 

Alginates are polysaccharides that are linear copolymers of (3-D-mannuronic acid and a-L-guluronic acid residues with (1 4) linkages, as shown in Figure 14.13 [24]. The molecular chain is formed by homopolymeric blocks or heteropolymeric blocks of the two monomers, (3-D-mannuronic acid or a-L-guluronic acid. Alginates exhibit molecular weights between 20 and 600 kDa [3]. 

Galactomannans, xanthan and chitosans are thickening linear polysaccharides the first one is neutral, xanthan is an anionic polysaccharide and chitosan is a cationic polymer in acidic conditions. The main physical properties of these different polysaccharides in dependence with the experimental conditions (temperature, ionic concentrations, nature of counterions...) are described. Considering alginates and gellan, a specific behaviour is observed physical gelation for which the mechanisms of gelation are discussed in relation with thermodynamic conditions. 

Polysaccharides from plants, too, can form gels in water. Pectin is used to help gel jams and fruit preserves. Some polysaccharides are used to thicken foods. Alginic acid, extracted from brown algae, is a linear polymer containing many carboxylic acid groups. The sodium salt is soluble in water and is used as a thickener in the preparation of ice cream and other foods. If a sodium alginate solution is mixed with calcium ion, the polysaccharide pre-... 

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