Biological activity of algal sulphated and non-sulphated polysaccharides

Abstract

Seaweeds are the main source of sulfated polysaccharides within vegetables. Sulfated heteropolysaccharides such as ulvans can be found in green seaweeds (Chlorophyta), while other sulfated polysaccharides such as fucans are present in brown seaweeds (Heterokontophyta, Pheophyceae) and sulfated galactans such as agar and carrageenan appear in red seaweeds (Rhodophyta). Research interest in several nonsulfated polysaccharides from brown seaweeds, such as alginate and laminaran, is increasing. Sulfated and nonsulfated polysaccharides play structural and storage roles in seaweeds and may exhibit many useful biological properties. Relevant pharmacological and medical properties of algal sulfated polysaccharides, such as anticoagulant, antioxidant, antiviral, antitumoral, and immunomodulary activities, have been reported both in vitro and in animal models. Other, less well known biological properties have also been described for algal polysaccharides, including an effect on lipid metabolism and glucose concentration and antiinflammatory, antiproliferative, antimicrobial, liver-protecting, and prebiotic effects. The addition of edible seaweeds or seaweed-derived ingredients to traditional foods can be considered a good strategy for increasing the value of the functional foods market.