Partial characterization and anticoagulant activity of a heterofucan from the brown seaweed Padina gymnospora

Abstract

The brown algae Padina gymnospora contain different fucans. Powdered algae were submitted to proteolysis with the proteolytic enzyme maxataze. The first extract of the algae was constituted of polysaccharides contaminated with lipids, phenols, etc. Fractionation of the fucans with increasing concentrations of acetone produced fractions with different proportions of fucose, xylose, uronic acid, galactose, and sulfate. One of the fractions, precipitated with 50% acetone (v/v), contained an 18-kDa heterofucan (PF1), which was further purified by gel-permeation chromatography on Sephadex G-75 using 0.2 M acetic acid as eluent and characterized by agarose gel electrophoresis in 0.05 M 1,3 diaminopropane/acetate buffer at pH 9.0, methylation and nuclear magnetic resonance spectroscopy. Structural analysis indicates that this fucan has a central core consisting mainly of 3-ß-Dglucuronic acid 1→ or 4-ß-D-glucuronic acid 1 →, substituted at C-2 with α-L-fucose or ß-D-xylose. Sulfate groups were only detected at C-3 of 4-α-L-fucose 1→ units. The anticoagulant activity of the PF1 (only 2.5-fold lesser than low molecular weight heparin) estimated by activated partial thromboplastin time was completely abolished upon desulfation by solvolysis in dimethyl sulfoxide, indicating that 3-Osulfation at C-3 of 4-α-L-fucose 1→ units is responsible for the anticoagulant activity of the polymer. Correspondence

Cytotoxicity of Fucoidan from Three Tropical Brown Algae Against Breast and Colon Cancer Cell Lines

“…13,30 The band at 1614 cm -1 indicated the stretching of asymmetric carboxylate O-C-O vibration. 28,29 The band at 1424 cm -1 suggested C-OH deformation vibration with contribution of O-C-O symmetric stretching vibration of carboxylate group. 29 The presence of O=S=O stretching vibration of sulphate esters was indicated by a band at 1258 cm-113, 28,29 The band at 1040 cm -1 corresponded to stretching vibration of C-O-C/C-OH.…”

“…The broad band centered at 3435 cm -1 assigned to hydrogen bonded O-H stretching vibration. [28][29][30] The band at 2939 cm -1 was attributed the C-H stretching pyranoid ring and C6 of fucose and/or galactose units. 13,30 The band at 1614 cm -1 indicated the stretching of asymmetric carboxylate O-C-O vibration.…”

“…30 The band at 820 cm -1 assigned the C-O-S bending vibration of sulfate group. [28][29][30][31] The band at 580 cm -1 indicated the asymmetric and symmetric O=S=O deformation of sulfate. 31 These FT-IR spectra analysis proved that the extraction and purification processes used and purification process used in this study were effective to obtain fucoidan from the three tropical brown algae.…”

Anticoagulant activity of sulfated polysaccharides fractions from an aqueous extract obtained from the red seaweed Halymenia floresia (Clemente) C. Agardh

“…This fact further justifies the occurrence of distinct SP into tissue of the studied species. Therefore, such disproportions in chemical composition also justify the complexity and heterogeneity of these polymers (FARIAS et al, 2000;GHOSH et al, 2004;SILVA et al, 2005;RODRIGUES et al, 2010aRODRIGUES et al, , 2011b. From these data (Table 1), we chose the Hf-SP 3 (80°C) which was submitted to ion-exchange chromatography on a DEAE-cellulose column, an important technique for separation of these compounds.…”

“…Furthermore, HEP is extracted in low concentrations in pig intestine or bovine lungs (THOMAS, 1997). Although seaweed SP have been described as anticoagulants for some time, difficulty of the isolation in pure form is still reported (ASSREUY et al, 2008;FARIAS et al, 2000FARIAS et al, , 2001LEITE et al, 1998;PUSHPAMALI et al, 2008;RODRIGUES et al, 2009;SILVA et al, 2005). Their heterogeneity and polydispersity limit their structural study (AZEVEDO et al, 2009;FARIAS et al, 2000;PEREIRA et al, 2005;RODRIGUES et al, 2009;YOON et al, 2007;ZHANG et al, 2008).…”