title: Structural features of two heteroxylan polysaccharide fractions from wheat bran with anti-complementary and antioxidant activities.
abstract: Wheat bran is a rich source of bioactive substances ascribed to its arabinoxylan component. Two water-soluble arabinoxylans were sequentially extracted from wheat bran. WB1, released during enzymatic digestion of starch and protein, contained medium-branched arabinoxylan (A/X=0.88) consisting of 3-O-substituted (22%), di-substituted (19.8%) and 58% unsubstituted Xylp residues. It was slightly contaminated with (1→3,1→4)-β-glucan and arabinogalactan, and free of protein. WB2 extracted with 0.5% NaOH contained ∼95% arabinoxylan (A/X=1.09). WB2 and two 5% NaOH-extracted arabinoxylans were rich in protein and phenolic compounds. All radical-scavenging assays indicated a relation with the protein and total phenolics contents. The protein-free WB1 displayed the highest hydroxyl radical scavenging effect indicating the distinct role of phenolic acids. The immunomodulatory activity of WB1 was somewhat lower, whereas, that of WB2 higher in comparison to the immunogenic polysaccharide PMII. The arabinoxylans have the potential as immuno-enhancing and antioxidant additives in functional foods.
authors: Slovak Academy of Science, Institute of Chemistry, Center for Glycomics, Dúbravská cesta 9, SK-845 38 Bratislava, Slovakia. hromadkova.z@gmail.com
authors: Zdenka
authors: Z
authors: Hromádková
authors: Berit Smestad
authors: BS
authors: Paulsen
authors: Martin
authors: M
authors: Polovka
authors: Zuzana
authors: Z
authors: Košťálová
authors: Anna
authors: A
authors: Ebringerová
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification* / Q000378:metabolism; D004043:Dietary Fiber / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000302:isolation & purification / Q000378:metabolism; D005685:Galactans / Q000302:isolation & purification / Q000378:metabolism; D007155:Immunologic Factors / Q000302:isolation & purification* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D010636:Phenols / Q000378:metabolism; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D014908:Triticum / Q000378:metabolism*; D014990:Xylans / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D004043:Dietary Fiber; D016166:Free Radical Scavengers; D005685:Galactans; D007155:Immunologic Factors; D010636:Phenols; D014990:Xylans; C085118:arabinoxylan; C005653:arabinogalactan