Alginic acid repeating units

Figure 8.5 D-Mannuronic and L-guluronic repeat units of alginic acid...

Figure 4. Enthalpy changes (9) (left scale) in calories per mole of the polymer repeating unit, and volume changes (O) (right scale) in milliliters per mole of the polymer repeating unit, on the addition of Cu(ClO ) to the sodium salt form (a = 1.0) of alginic acid S-35 in 0.05M NaClO, at 25°C. [Cu ]/[P] stands for the molar ratio of the total copper(II) to the polymer repeating unit.

The exopolysaccharides produced by Pseudomonas aeruginosa and Azoto-bacter vinelandii, differ from those produced by other Gram-negative bacteria, in that the heterosaccharide appears to lack a repeating unit. These polymers consist of mannuronic acid and guluronic acid and closely resemble the alginates produced by marine algae. 

FIGURE 5.1 Structure of alginic acid. The symbol indicates the repeating units of the polymer chain. 

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