Algal extract comprising sulphated and non-sulphated polyanionic polysaccharides and uses thereof

1. A method for treating depression, the method comprising the administration, to a subject in need thereof, of an effective amount of an algal extract from the order of Ulvales comprising sulphated and non-sulphated polyanionic polysaccharides, the size of which is less than or equal to 50 kDa, wherein the algal extract is prepared by a process comprising the following steps:

a) washing the algae and freeing the algae of sand;

b) crushing the washed and freed algae to create a crushed product comprising a solid phase and a liquid phase;

c) separating the solid phase of the crushed product from the liquid phase of the crushed product;

d) clarifying the separated liquid phase to form a juice;

e) filtering the juice with a membrane of less than 50 kDa; and

f) concentrating the filtered juice; and

g) drying the concentrated juice.

2. The method according to claim 1 , wherein the extract is an extract of green algae of the type Ulva.

3. The method according to claim 1 , wherein said polysaccharides comprise mannose and/or arabinose.

4. The method according to claim 3 , wherein said polysaccharides comprise at least 0.005% of mannose and/or at least 0.005% of arabinose, by weight based on the weight of the total dry material of the algal extract.

5. The method according to claim 4 , wherein said polysaccharides comprise mannose at an amount in a range from 0.01 to 0.20% and arabinose at an amount in the range of 0.01 to 0.5%, by weight based on the weight of the total dry material of the algal extract.

6. The method according to claim 1 , wherein said polysaccharides further comprise

galactose, glucose, rhamnose, xylose, and glucuronic acid.

7. The method according to claim 6 , wherein:

the galactose is at an amount in the range of 0.05 to 0.5%;

the glucose is at an amount in the range of 0.005 to 0.05%;

the rhamnose is at an amount in the range of 2 to 15%;

the xylose is at an amount in the range of 0.1 to 1%; and

the glucuronic acid is at an amount in the range of 1 to 7%;

by weight based on the weight of the total dry material of the algal extract.

8. The method according to claim 1 , wherein said polysaccharides have a size of less than or equal to 15 kDa.

9. The method according to claim 1 , wherein the algal extract comprises:

carbon at an amount in the range of 10 to 50%;

hydrogen at an amount in the range of 1 to 10%;

nitrogen at an amount in the range of 1 to 5%;

oxygen at an amount in the range of 20 to 50%; and

sulphur at an amount in the range of 1 to 15%;

in weight percentage of the total dry material of the algal extract.

10. The method according to claim 1 , wherein the algal extract comprises:

carbon at an amount in the range of 15 to 30%;

hydrogen at an amount in the range of 3 to 6%;

nitrogen at an amount in the range of 1 to 3%;

oxygen at an amount in the range of 25 to 40%; and

sulphur at an amount in the range of 2.5 to 10%;

in weight percentage of the total dry material of the algal extract.

11. The method according to claim 1 , wherein membrane is a 15 kDa membrane.

12. The method according to claim 1 , wherein solid phase is separate from the liquid phase by pressing the crushed product.

13. The method according to claim 1 , wherein:

the algae is washed in freshwater;

the algae are crushed with a refiner;

the solid phase of the crushed product is separated from the liquid phase of the crushed product by pressing the crushed product with a belt press;

the separated liquid phase is clarified with a clarifier with disc stacks;

the membrane is a 15 kDa ceramic membrane;

the filtered juice is concentrated by evaporation; and/or

the concentrated juice is dried by freeze-drying or atomization.

14. The method according to claim 1 , wherein the composition further comprises for at least one pharmaceutically acceptable excipient.