title: Potential antioxidant capacity of sulfated polysaccharides from the edible marine brown seaweed Fucus vesiculosus.
abstract: Fucus vesiculosus was sequentially extracted with water at 22 degrees C (fraction 1 (F1)) and 60 degrees C (F2), and with 0.1 M HCl (F3) and 2 M KOH (F4) at 37 degrees C. Soluble fractions (42.3% yield) were composed of neutral sugars (18.9-48 g/100 g), uronic acids (8.8-52.8 g/100 g), sulfate (2.4-11.5 g/100 g), small amounts of protein (< 1-6.1 g/100 g), and nondialyzable polyphenols (0.1-2.7 g/100 g). The main neutral sugars were fucose, glucose, galactose, and xylose. Infrared (IR) spectra of the fractions showed absorption bands at 820-850 and 1225-1250 cm(-1) for sulfate. F1, F2, and F4 also exhibited an absorption band at 1425 cm(-1), due to uronic acids, and their IR spectra resembled that of alginate. F3 had an IR spectrum similar to that of fucoidan with an average molecular weight of 1.6 x 10(6) Da, calculated by molecular exclusion high-performance liquid chromatography. The presence of fucose in this polysaccharide was confirmed by (1)H NMR spectroscopy. This fraction showed the highest potential to be antioxidant by the ferric reducing antioxidant power (FRAP) assay, followed by the alkali- and water-soluble fractions. Sulfated polysaccharides from edible seaweeds potentially could be used as natural antioxidants by the food industry.
authors.affiliation: Departamento de Metabolismo y Nutrición, Instituto del Frío, Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Universitaria s/n, E 28040 Madrid, Spain. pruperez@if.csic.es
authors.forename: Pilar
authors.initials: P
authors.lastname: Rupérez
authors.forename: Oussama
authors.initials: O
authors.lastname: Ahrazem
authors.forename: J Antonio
authors.initials: JA
authors.lastname: Leal
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D005290:Ferric Compounds / Q000737:chemistry; D005643:Fucose / Q000032:analysis; D005690:Galactose / Q000032:analysis; D005947:Glucose / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D000459:Phaeophyceae / Q000737:chemistry*; D011134:Polysaccharides / Q000032:analysis* / Q000494:pharmacology; D012624:Seaweed / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013431:Sulfates / Q000032:analysis* / Q000494:pharmacology; D014574:Uronic Acids / Q000032:analysis; D014994:Xylose / Q000032:analysis
chemical_list: D000975:Antioxidants; D005290:Ferric Compounds; D011134:Polysaccharides; D013431:Sulfates; D014574:Uronic Acids; D005643:Fucose; C007789:fucoidan; D014994:Xylose; D005947:Glucose; D005690:Galactose