Potential anti-angiogenic, antiproliferative, antioxidant, and anticoagulant activity of anionic polysaccharides, fucans, extracted from brown algae Lobophora variegata

This study analyzed the action of sulfated polysaccharides, fucans, from the brown alga Lobophora variegata on angiogenesis (CAM assays), antioxidant activity, and homeostasis in vitro. Groups of fucans, obtained after acetone fractionation in several (0.3-1.5 v) concentrations, were obtained. This sulfated heterofucan was eluted with 0.8 v of acetone named fraction rich in fucans (FRF). The presence of polysaccharides had its homogeneity confirmed by electrophoresis in agarose with buffer 1,3-diaminopropane and sulfate groups by chemical analyses. We observed that FRF showed antioxidant activity with strong inhibition of hydroxyl and strong inhibition of peroxide. FRF at 25 mu g mL(-1) decreased the cellular viability (54.2 +/- 0.2 %) using the MTT assay in tumor cell line HepG2 (hepatocellular liver carcinoma cell line). This polysaccharide exhibited anti-angiogenic effect and anticoagulant activity on intrinsic pathway (activated partial thromboplastin time (aPTT). The results showed that FRF from L. variegata has significant pharmacological activity in models of anticoagulation, angiogenesis, and inhibition of free radicals.