Purification of inositol from plant materials
Phytate and/or phytin and/or phytic acid in an aqueous slurry of plant material is partially hydrolyzed by incubating the slurry with an enzyme product enriched in phytase. The soluble fraction of the slurry is separated into anionic and neutral fractions. The anionic fraction is then hydrolyzed further, and the hydrolyzate is separated into second ionic and neutral fractions. The second neutral fraction thus obtained is rich in inositol, and does not contain significant quantities of other sugars which would be hard to separate from it.
1. A process for producing inositol from plant materials comprising the steps of:
a) providing a plant material comprising a neutral soluble sugar and at least one of a phytate or a phytin;
b) providing an aqueous slurry of said plant material from step a),
wherein said aqueous slurry of said plant material comprises said neutral soluble sugar of said plant material and said at least one of a phytate or a phytin of said plant material;
c) conducting a partial hydrolysis by treating said aqueous slurry of said plant material resulting from step b) with an enzyme product enriched in phytase enzyme to partially hydrolyze said at least one of a phytate or a phytin to produce a partially hydrolyzed slurry comprising a mixture of inositol phosphates which are negatively charged, and wherein said plant material is a main source of the phytate or phytin which is partially hydrolyzed during said step of a partial hydrolysis;
d) separating said partially hydrolyzed slurry of said plant material resulting from step c) to produce a water soluble fraction and a water-insoluble fraction, wherein said water soluble fraction comprises inositol phosphates which are negatively charged, as well as said neutral soluble sugar of said plant material;
e) separating said water soluble fraction resulting from step d) into a first ionic fraction comprising inositol phosphates which are negatively charged and a first neutral fraction comprising said neutral soluble sugar of said plant material;
f) conducting a hydrolysis of said inositol phosphates of said first ionic fraction resulting from step e) to produce inositol and an anionic fraction; and
g) separating said inositol from said anionic fraction resulting from step f.
2. The process of claim 1 , wherein said enzyme product in step c) does not include an acid phosphatase.
3. The process of claim 1 wherein said step of treating the aqueous slurry in step c) is carried out at a pH between about 3.0 and about 7.0.
4. The process of claim 3 , wherein said enzyme product in step c) comprises an acid phosphatase.
5. The process of claim 1 , wherein said step of separating the partially hydrolyzed slurry into a water-soluble fraction and a water-insoluble fraction in step d) is carried out by centrifugation.
6. The process of claim 1 , wherein said step of separating the partially hydrolyzed slurry into a water-soluble fraction and a water-insoluble fraction in step d) is carried out by filtration.
7. The process of claim 1 , in which the step of conducting a hydrolysis of said inositol phosphates of said first ionic fraction in step f) comprises treating said first ionic fraction with a phytase.
8. The process of claim 1 , in which the step of conducting a hydrolysis of said inositol phosphates of said first ionic fraction in step f) comprises treating said first ionic fraction with an acid phosphatase.
9. The process of claim 8 , wherein said step of conducting a hydrolysis in step f) is carried out at a pH of less than 4.
10. The process of claim 3 , in which the step of conducting a hydrolysis of said inositol phosphates in said first ionic fraction in step f) comprises treating said first ionic fraction with a phytase.
11. The process of claim 3 , in which the step of conducting a hydrolysis of said inositol phosphates in said first ionic fraction in step f) comprises treating said first ionic fraction with acid phosphatase.
12. The process of claim 11 , wherein said step of conducting a hydrolysis in step f) is carried out at a pH of less than 4.
13. The process of claim 4 , in which the step of conducting a hydrolysis of said inositol phosphates in said first ionic fraction in step f) comprises treating said first ionic fraction with acid phosphatase, and wherein said hydrolysis is carried out at a pH of less than 4.
14. The process of claim 1 , wherein the step of conducting a hydrolysis of inositol phosphates of said first ionic fraction in step f) is achieved free of enzyme based catalysis.
15. The process of claim 1 , further comprising the step of producing a product comprising said inositol resulting from step g).