title: Purification of alginate oligosaccharides with root growth-promoting activity toward lettuce.
abstract: Sodium alginate was degraded by alginate lyase from Corynebacterium sp., and the product was purified by an ultrafiltration (UF) membrane module. The UF treatment was carried out at a transmembrane pressure of 0.15 MPa and a flow velocity of 0.6 m/s in the cross-flow mode, and non-degraded alginate was almost completely removed. The alginate oligosaccharide obtained was a mixture of di- to octasaccharides and had promoting activity toward lettuce root elongation (about 2-fold compared with the control) in the concentration range of 200-3000 microg/ml. The effect of the degree of polymerization on this activity was examined by using each oligosaccharide fractionated by gel chromatography. The tri-, tetra-, penta- and hexasaccharides were each found to have root growth-promoting activity in a lettuce bioassay.
authors.affiliation: Food Research Institute, Kagawa Prefectural Government, Takamatsu, Japan. hakkou@mb.kagawa-net.or.jp
authors.forename: K
authors.initials: K
authors.lastname: Iwasaki
authors.forename: Y
authors.initials: Y
authors.lastname: Matsubara
mesh_terms: D000464:Alginates / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D001681:Biological Assay; D002850:Chromatography, Gel; D003352:Corynebacterium / Q000201:enzymology; D018545:Lactuca / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development*; D011133:Polysaccharide-Lyases / Q000378:metabolism*; D014462:Ultrafiltration
chemical_list: D000464:Alginates; D011133:Polysaccharide-Lyases