β-carrageenan, processes for its preparation, and uses therefor

Abstract

Purified and substantially pure beta-carrageenan and processes for their preparation. Purified beta-carrageenan can be obtained from a marine macroalga containing beta-carrageenan and/or a precursor thereof by the steps of:A. where the macroalga contains a precursor of beta-carrageenan, reacting the macroalga with an alkaline compound to convert the precursor to beta-carrageenan,B. extracting carrageenan from the macroalga,C. treating the extracted carrageenan with an aqueous quaternary ammonium salt to form a precipitate and an aqueous solution,D. separating the solution from the precipitate, andE. isolating purified beta-carrageenan from the solution.Substantially pure beta-carrageenan can be obtained from purified beta-carrageenan by the further steps of:F. forming a solution of purified beta-carrageenan in water,G. contacting the solution with an ion exchange agent that removes carrageenan which contains sulfate ester from the solution,H. removing the resulting solution from contact with the ion exchange agent, andI. isolating substantially pure beta-carrageenan from the solution.

What is claimed is:  
     
       1. β-carrageenan in purified form containing less than 2% by weight of sulfate ester. 
     
     
       2. β-carrageenan of  claim 1  which contains less than about 1.75% by weight of sulfate ester. 
     
     
       3. β-carrageenan in substantially pure form containing less than 1 % by weight of sulfate ester. 
     
     
       4. β-carrageenan of  claim 3  which contains less than about 1% by weight of sulfate ester. 
     
     
       5. β-carrageenan according to  claim 1  wherein said purified form is derived from the marine macroalgae  Eucheuma gelatinae  or  Eucheuma speciosa.    
     
     
       6. β-carrageenan according to  claim 2  wherein said purified form is derived from the marine macroalgae  Eucheuma gelatinae  or  Eucheuma speciosa.    
     
     
       7. β-carrageenan according to  claim 3  wherein said purified form is derived from the marine macroalga e  Eucheuma gelatinae  or  Eucheuma speciosa.    
     
     
       8. β-carrageenan according to  claim 4  wherein said purified form is derived from the marine macroalgae  Eucheuma gelatinae  or  Eucheuma speciosa.    
     
     
       9. β-carrageenan according to  claim 1  wherein said purified form is derived from the marine macroalgae  Eucheuma gelatinae.    
     
     
       10. β-carrageenan according to  claim 2  wherein said purified form is derived from the marine macroalga  Eucheuma gelatinae.    
     
     
       11. β-carrageenan according to  claim 3  wherein said purified form is derived from the marine macroalga  Eucheuma gelatinage.    
     
     
       12. β-carrageenan according to  claim 4  wherein said purified form is derived from the marine macroalga  Eucheuma gelatinae.    
     
     
       13. β-carrageenan according to  claim 1  wherein said purified form is derived from the marine macroalga  Eucheuma speciosa.    
     
     
       14. β-carrageenan according to  claim 2  wherein said purified form is derived from the marine macroalga  Eucheuma speciosa.    
     
     
       15. β-carrageenan according to  claim 3  wherein said purified form is derived from the marine macroalga  Eucheuma speciosa.    
     
     
       16. β-carrageenan according to  claim 4  wherein said purified form is derived from the marine macroalga  Eucheuma speciosa.