Appeal No. 2003-1010
Application 09/357,393
acid produced has a degree of polymerization of less than 20 and
is substantially free of mannuronic acid contamination.1 Claim 1
is illustrative:
1. A process for producing polyguluronic acids, having
degrees of polymerization less than 20 and substantially free of
mannuronic acid contamination, comprising the steps of:
(a) providing a solution containing 5 wt.% or more of
alginic acid prepared by dissolving alginic acid by
neutralization with an organic base;
(b) hydrolyzing the alginic acid to low molecular weight
components including polyguluronic acids while maintaining the pH
of the solution on the acid side of neutrality;
(c) acidifying the solution to selectivity precipitate
acids; and
(d) separating the polyguluronic acids from the acidified
solution.
THE REFERENCES
Yamada 5,558,973 Sep. 24, 1996
Arne Haug et al. (Haug), “Studies on the Sequence of Uronic Acid
Residues in Alginic Acid”, 21 Acta Chem. Scand. 691-704 (1967).
Doublier and Cuvelier (Doublier), “II. Behavior of
Polysaccharides in Aqueous Solutions - A. Solubilization: A
Critical Step”, in Carbohydrates in Food 287-89 (Ann-Charlotte
Eliasson ed., Marcel Dekker 1996).
1 The appellant states that “[t]he expression ‘substantially
free of mannuronic acid contamination’ as used herein means that
the mannuronic acid content is less than about 8 wt.%, and
preferably less than about 5 wt.%” (specification, page 5,
lines 33-36).
2
Page: Previous 1 2 3 4 5 6 7 Next
Last modified: November 3, 2007