PHYCOCYANIN PURIFICATION PROCESS

Abstract

The present invention relates to a process for purifying phycocyanins from a solution comprising phycocyanins and glycogen, said phycocyanins being produced by microorganisms belonging to the order Cyanidiales, characterized in that it comprises (i) an enzymatic degradation step of glycogen with an enzyme suitable for degrading glycogen at a pH below 6 and a reaction temperature below 40°C, said enzyme being selected from a pectinase, a glucoamylase, or a mixture of a pectinase and a pullulanase, and (ii) a step of separating phycocyanins from the glycogen degradation products.

Claims

1. A process for purifying phycocyanins from a solution comprising phycocyanins and glycogen, characterized in that it comprises (i) an enzymatic degradation step of glycogen with an enzyme suitable for degrading glycogen at a pH below 6 and a reaction temperature below 40 °C and (ii) a step of separating phycocyanins from the glycogen degradation products.

2. The process according to claim 1, characterized in that the temperature is less than 30°C and / or the pH is less than or equal to 5.

3. The process according to any of claims 1 or 2, characterized in that the enzyme has α1-4 glucosidase or polygalacturonase activity.

4. The process according to claim 3, characterized in that the enzyme is a pectinase.

5. The process according to any of claims 1 to 4, characterized in that the enzyme is a mixture of enzymes comprising an enzyme with α1-6 glucosidase activity in addition to the enzyme with α1-4 glucosidase or polygalacturonase activity.

6. The process according to claim 5, characterized in that the enzyme with cd-6 glucosidase activity is a pullulanase.

7. The process according to claim 6, characterized in that the enzyme mixture comprises a pectinase and a pullulanase.

8. The process according to any of claims 1 to 3, characterized in that the enzyme has α1-4 glucosidase or polygalacturonase activity and α1-6 glucosidase activity.

9. The process according to claim 8, characterized in that the enzyme is a glucoamylase.

10. The process according to any of claims 1 to 9, characterized in that the solution comprising the phycocyanin(s) and glycogen is an unpurified suspension obtained after cell lysis of a biomass of phycocyanin-producing microorganisms.

11. The process according to any of claims 1 to 10, characterized in that the solution comprising the phycocyanin(s) and glycogen is an unpurified solution obtained after filtration of an unpurified suspension itself obtained after cell lysis of a biomass of phycocyanin-producing microorganisms.

12. A process for producing a phycocyanin of microbial origin comprising the steps of (a) culturing phycocyanin-producing microorganisms as described above under culture conditions to produce a fermentation wort comprising more than 30 g / L dry matter and at least 4% phycocyanin on a dry matter basis, (b) cell lysis to release the produced phycocyanin and glycogen to obtain an unpurified suspension as defined above, (c) separation of the unpurified suspension to recover an unpurified solution comprising phycocyanin and glycogen, and then optionally (d) isolating phycocyanin from the unpurified solution, then optionally (e) purifying the isolated phycocyanin, characterized in that an enzymatic lysis step of glycogen is carried out with an enzyme suitable for degrading glycogen at a pH below 6 and a temperature reaction temperature below 40 °C,This enzymatic lysis is carried out in the unpurified suspension obtained in (b) and / or in the unpurified solution obtained in (c).

13. The process according to claim 12, characterized in that the temperature is less than 30°C and / or the pH is less than or equal to 5.

14. The process according to any of claims 12 or 13, characterized in that the enzyme has either α1-4 glucosidase or polygalacturonase activity.

15. The process according to claim 14, characterized in that the enzyme is a pectinase.

16. The process according to any of claims 12 to 15, characterized in that the enzyme is a mixture of enzymes comprising an enzyme with α1-6 glucosidase activity in addition to the enzyme with α1-4 glucosidase or polygalacturonase activity.

17. The process according to claim 16, characterized in that the enzyme with α1-6 glucosidase activity is a pullulanase.

18. The process according to claim 17, characterized in that the enzyme mixture comprises a pectinase and a pullulanase.

19. The process according to any of claims 12 to 14, characterized in that the enzyme has α1-4 glucosidase or polygalacturonase activity and α1-6 glucosidase activity.

20. The process according to claim 19, characterized in that the enzyme is a glucoamylase.

21. The process according to any of claims 12 to 20, characterized in that the solution comprising the phycocyanin(s) and glycogen is an unpurified suspension obtained in (b).

22. The process according to any of claims 12 to 20, characterized in that the enzymatic lysis is carried out in the unpurified solution obtained in (c).

23. The process according to any of claims 12 to 22, characterized in that the phycocyanin is a phycocyanin of microbial origin, produced by a microorganism selected from the species of the genera Arthrospira, Spirulina, Synechococcus, Cyanidioschyzon, Cyanidium and Galdieria, more particularly Galdieria sulfuraria.

24. An isolated phycocyanin obtained by the process according to any of claims 1 to 23.

25. The phycocyanin isolated according to claim 24, characterized in that it comprises traces of enzymes with alpha 1-4 and / or 1-6 glucosidase activity. Qb / RCn / l 7P7 / Σ1 / YILI 26. Phycocyanin isolated according to any of claims 24 or 25, characterized in that it contains glucose oligomers, products of the enzymatic lysis of glycogen.

27. A phycocyanin extract comprising phycocyanin and glycogen, characterized in that the dry weight ratio of glycogen to phycocyanin is less than 6, and characterized in that it comprises traces of enzymes with alpha 1-4 and / or 1-6 glucosidase activity and / or glucose oligomers, products of the enzymatic lysis of glycogen.

28. The extract according to claim 27, characterized in that the ratio by dry weight of glycogen and phycocyanin is less than 4.

29. The extract according to claim 27, characterized in that the ratio by dry weight of glycogen and phycocyanin is less than 3.

30. The extract according to claim 27, characterized in that the ratio by dry weight of glycogen to phycocyanin is less than 2.

5.

31. The extract according to claim 27, characterized in that the ratio by dry weight of glycogen and phycocyanin is less than 1.

32. The use of an isolated phycocyanin according to any of claims 24 to 26 or an extract according to any of claims 27 to 31 as a food coloring.

33. A food, characterized in that it comprises an isolated phycocyanin according to any of claims 24 to 26 or an extract according to any of claims 27 to 31.