title: Characterization, refining and antioxidant activity of saccharides derived from hemicelluloses of wood and rice husks.
abstract: Samples of rice husks, Eucalyptus globulus wood and Pinus pinaster wood (containing arabinoxylan, acetylated glucuronoxylan and acetylated glucomannan as major hemicellulose components, respectively) were subjected to autohydrolysis. The resulting liquid phases, containing mainly hemicellulose-derived saccharides, were refined by physicochemical methods to reduce their contents of monosaccharides and non-saccharide compounds. Raw autohydrolysis liquors and refined concentrates coming from aqueous treatments were assayed for antioxidant activity using the following assays: reducing power (FRAP), DPPH and ABTS radical scavenging activity and protection of β-carotene-linoleic emulsions from oxidation. The reducing power and radical scavenging capacity of the non refined fractions were comparable to the ones determined for the reference compound butylhydroxytoluene. Hemicellulose concentrated from the different feedstocks and refining protocols showed a dose dependent antioxidant activity in the range of concentrations evaluated. The in vitro antioxidant activity of concentrates correlated with their phenolic content.
authors.affiliation: Chemical Engineering Department, Polytechnical Building, University of Vigo (Campus Ourense), As Lagoas, 32004 Ourense, Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Rivas
authors.forename: Enma
authors.initials: E
authors.lastname: Conde
authors.forename: Andrés
authors.initials: A
authors.lastname: Moure
authors.forename: Herminia
authors.initials: H
authors.lastname: Domínguez
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Parajó
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D005052:Eucalyptus / Q000737:chemistry*; D006868:Hydrolysis; D012275:Oryza / Q000737:chemistry*; D010084:Oxidation-Reduction; D028223:Pinus / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D014934:Wood / Q000737:chemistry
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D011134:Polysaccharides; C007916:hemicellulose