What actually is polysulphate ester found in the cell wall of Rhodophyceae? is it the same as hydrocolloids found in them?

Polysulphate ester in Red algae are the characteristic pigment that are found in the cell wall. No, they are not the same as hydrocolloids . Hydro colloids are the suspension of particles in the water that binds to the water molecules and to one another and they retard the flow of liquid or solidify them. They are basically polysaccharides having high molecular weight.