Size-dependent pharmacological activities of differently degraded fucoidan fractions from Fucus vesiculosus.

Fucose-containing sulfated glycans (syn. fucoidans) from brown algae exhibit a wide range of bioactivities and are therefore considered promising candidates for health-supporting and medical applications. In this study, we investigated the pharmacological activities of fucoidan from Fucus vesiculosus and 18 gradually depolymerized fractions, which were obtained by hydrothermal and H2O2 treatment, respectively. All the activities decreased with decreasing molecular mass (Mw) but to a different extent resulting in some modified pharmacological profiles in dependence on the Mw as well as on the degradation method. H2O2 treatment was not only more efficient, simpler and cheaper than hydrothermal degradation, but also led to superior activity profiles and additionally eliminated co-extracted contaminants. Compared to heparin, the prime example of biologically active sulfated glycans, evenly sized H2O2 fractions exhibited considerable effects being relevant for anti-inflammatory activity, however only negligible anticoagulant activity and FXII activating potency. Due to their improved biopharmaceutical characteristics and favorable activities, degraded fucoidan fractions are worth to be further investigated as anti-inflammatory and anticomplementary agents.