| US 7,556,946 B2 | ||
| Cell wall derivatives from biomass and preparation thereof | ||
| Marie-France Versali, Tilff (Belgium); Fabienne Clerisse, Braives (Belgium); Jean-Michel Bruyere, Liège (Belgium); and Sandrine Gautier, Liège (Belgium) | ||
| Assigned to Kitozyme S.A., Herstal (Belgium) | ||
| Appl. No. 10/504,046 PCT Filed Feb. 12, 2003, PCT No. PCT/EP03/01375 § 371(c)(1), (2), (4) Date Jan. 28, 2005, PCT Pub. No. WO03/068824, PCT Pub. Date Aug. 21, 2003. |
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| Claims priority of application No. 2002/0093 (BE), filed on Feb. 12, 2002. | ||
| Prior Publication US 2005/0130273 A1, Jun. 16, 2005 | ||
| Int. Cl. C12P 19/04 (2006.01); C12P 1/02 (2006.01); C08B 37/08 (2006.01); C07H 1/06 (2006.01); C07H 1/08 (2006.01) | ||
| U.S. Cl. 435—101 [435/171; 536/20; 536/127] | 4 Claims |
| 1. A method for preparing chitosan from fungal or yeast chitin comprising the subsequent steps of:
a) isolating chitin polymers or chitin-rich chitin-glucan copolymers from fungal or yeast biomass,
b) contacting said isolated chitin polymers or chitin-rich chitin-glucan copolymers with an alkaline solution at a temperature
of 100 to 120° C. for 30 to 300 minutes at a weight ratio of alkali to the amount of dry chitin contained in the chitin polymers
or chitin rich chitin-glucan co-polymers of step a) which is between 1 and 20 (w/w), whereby an alkali-soluble fraction and
an alkali-insoluble fraction is obtained and whereby said alkali-soluble fraction is discarded and said alkali-insoluble fraction
is retained,
c) contacting said alkali-insoluble fraction with an acidic solution, by suspending said alkali-insoluble fraction and bringing
said suspended fraction into contact with said acidic solution whereby an acid-insoluble fraction and an acid-soluble fraction
is obtained and whereby said acid-insoluble fraction is discarded and said acid-soluble fraction comprising chitosan is retained.
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