D-Mannuronic acid sodium salt

D-Mannuronic acid (ManA) is a hexuronic acid having the CH2OH at C5 of mannose replaced by a carboxyl group (Collins, 2006). The major source of D-mannuronic acid is the polysaccharide, alginic acid, found in brown seaweeds (Phaeophyceae). The polysaccharide is a linear glycuronan consisting of (1+4)-linked residues of D-mannuronic acid and L-guluronic acid arranged in a block fashion in the polymer chain, with blocks containing one type of residue being separated by segments in which the two residues aIternate (Percival, 1967). In addition to algal sources, two genera of bacteria have been shown to secrete alginate-like polysaccharides, Pseudomonas and Azotobacter. Most of the research into bacterial alginate biosynthesis has been conducted on the opportunistic human pathogen Pseudomonas aeruginosa or the soil dwelling Azotobacter vinelandii. In both cases, bacterial alginate is partially acetylated (Hay, 2013).