Block alginate

Alginates are polysaccharides wih gel-forming properties composed of 1,4-linked P-D-mannuronic acid, a-L-guluronic acid and alternating P-D-mannuronic acid-a-L-guluronic acid blocks. Alginates stimulated human monocytes to produce high levels of tumour necrosis factor-a, interleukin-6 and interleukin-1 (Otterlei et al. 1991). 

Fig. 5.5 (A) Alginate block copolymer structure with random sequences (B) divalent cations induced gelation of alginate (formation of egg-box structure).

Alginic Acid + Aluminum Hydroxide Magnesium Tnsilicate (Gaviscon) [Antacid] [OTC] Uses Heartburn hiatal hernia pain Action Protective layer blocks gastric acid Dose 2—4- tabs or 15-30 mL PO qid followed by H2O Caution [B, -] Avoid in renal impair or Na -restricted diet Disp Tabs, susp SE D, constipation Interactions T Absorption OF tetracyclines EMS None OD May cause constipation, loss of appetite, muscle weakness, and peripheral edema symptomatic and supportive... 

Formation of L-guluronic acid, a component of the alginic acid-like polysaccharide produced by P. aeruginosa and Azotobacter vinelandii, requires special comment. In this case, a polymer built from /3-(l- 4)-linked D-mannosyluronic acid residues serves as an intermediate in the biosynthesis.204,205 Part of the D-mannosyluronic acid residues in the polymer is subjected to an epimerization at C-5 catalyzed by an exocellular enzyme of the micro-organism,205-207 producing a polysaccharide composed of structural blocks that contain only D-mannosyluronic acid or only l-gulosyluronic acid residues, as well %s some having both. The mechanism of the epimerization remains unclear. 

Metabolites may be incorporated into agar, alginate, or carrageenan blocks or strips that contain additives for nutritional and palatability requirements. The artificial food must have a similar nutritional value and color to the natural food higher quality foods may be preferred even if an antifeedant is present, while some consumers, particularly fish, may use visual cues to determine food choices.21... 

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