Soluble β-1,3/1,6-glucan in seaweed from the southern hemisphere and its immunomodulatory effect

► Soluble β-1,3/1,6-glucan was detected in seaweed from the southern hemisphere. ► YBGL-enzymatic kit was used for the confirmation of β-1,3/1,6-glucan polymers. ► A process was presented for production thereof with good recovery percentages. ► Composition and structure provided comprising a β-1,3-glucan with β-1,6 side links. ► Immunomodulatory activity of the soluble β-1,3/1,6-glucan extract was established.