Molecular characterization and immunomodulatory activity of sulfated fucans

Abstract

The sulfated-fucans, called fucoidans, are complex, heterogeneous and bioactive macromolecules consisting mainly of &#61537 -L-fucopyranosyl residues with a covalently linked sulfate, and are commonly found in the cell walls of brown algae. Thestructural backbones of fucoidans have been largely classified into two groups, including (1→3)-linked α-L-fucopyranose residues from Laminaria saccharina, Cladosiphon okamuranus and Chorda filum, and (1→3)- and (1→4)-linked α-Lfucopyranoseresidues from Ascophyllum nodosum and Fucus spp.. However, species-specific fucoidans have been found with variation in their glycosidic patterns, monosaccharide units, sulfate content and site of sulfation. In addition, differencesin uronic acid content and in branching levels impose a further complexity in the study of fucoidans. Fucoidans have garnered attention mainly because of their diverse biological activities, including antioxidant, anticoagulant, antiviral, anticancerand immunomodulatory activities. A considerable reduction in the viability of Lewis lung carcinoma cells and in proliferation rate of human melanoma cells were observed by the treatment of fucoidans isolated from Sargassum spp., Fucusvesiculosus and F. evanescens. Fucoidan from F. vesiculosus was also reported to be a potent immunomodulator, improving the development and growth of dendritic cells through the induction and release of interleukin (IL)-12 an Thestructural backbones of fucoidans have been largely classified into two groups, including (1→3)-linked α-L-fucopyranose residues from Laminaria saccharina, Cladosiphon okamuranus and Chorda filum, and (1→3)- and (1→4)-linked α-Lfucopyranoseresidues from Ascophyllum nodosum and Fucus spp.. However, species-specific fucoidans have been found with variation in their glycosidic patterns, monosaccharide units, sulfate content and site of sulfation. In addition, differencesin uronic acid content and in branching levels impose a further complexity in the study of fucoidans. Fucoidans have garnered attention mainly because of their diverse biological activities, including antioxidant, anticoagulant, antiviral, anticancerand immunomodulatory activities. A considerable reduction in the viability of Lewis lung carcinoma cells and in proliferation rate of human melanoma cells were observed by the treatment of fucoidans isolated from Sargassum spp., Fucusvesiculosus and F. evanescens. Fucoidan from F. vesiculosus was also reported to be a potent immunomodulator, improving the development and growth of dendritic cells through the induction and release of interleukin (IL)-12 an