Diverse patterns of cell wall mannan/galactomannan occurrence in seeds of the Leguminosae.

Endosperms from seeds of different subfamilies of Leguminosae were submitted to sequential aqueous and alkaline aqueous extractions. The extractions from species belonging to the Mimosoideae and Faboideae subfamilies yielded galactomannans with constant Man:Gal ratios, whereas the extractions from Caesalpinioideae seeds gave rise to galactomannans with increasing values of the Man:Gal ratio. The presence of a family of galactomannans within the same species may be a trait found only in Caesalpinioideae subfamily.

Isolation of a lectin and a galactoxyloglucan from Mucuna sloanei seeds.

A lectin and a galactoxyloglucan were characterized from Mucuna sloanei seed cotyledons. The galactoxyloglucan, isolated by water extraction and ethanol precipitation, had Glc:Xyl:Gal proportions in a molar ratio of 1.8:1.

Two galactomannan preparations from seeds from Mimosa scabrella (bracatinga): Complexation with oxovanadium(IV/V) and cytotoxicity on HeLa cells.

Two galactomannans, GALMAN-A and GALMAN-B, were isolated from seeds of Mimosa scabrella (bracatinga), with deactivation and exposure to native enzymes, respectively. They were treated with oxovanadium(IV) and oxovanadium(V), designated (VO(2+)/VO(3+)) to form GALMAN-A:VO(2+)/VO(3+) and GALMAN-B:VO(2+)/VO(3+) complexes, respectively. The potentiometric studies provided the binding constants for the complexes and the resulting complexed species were a function of pH.

Changes in cell wall composition associated with maturation in the gymnosperm Araucaria angustifolia.

A general structural characterization and an investigation on the dynamics of formation of cell wall polysaccharides was performed, using plantlets stem samples from a typical gymnosperm from southern Brazil, Araucaria angustifolia, as experimental model. Microscopic examination and monosaccharide composition of plantlet segments at different heights were carried out to show the representative portions of stem cell wall development. The plantlets were divided in portions (tip, middle and base) which were submitted to sequential extractions.

Complexation of vanadium(V) oxyanions with hexopyranose- and mannopyranoseuronic acid-containing polysaccharides: stereochemical considerations.

Carbohydrates containing galactopyranosyl and mannopyranosyl units with vicinal cis-diols were treated with NaVO(3) in D(2)O, and complexation was determined by (51)V NMR spectroscopy. Me alpha-Galp, Me beta-Galp (3,4-cis-diols), and Me alpha-Manp (2,3-cis-diol) complexed, but Me beta-Manp barely did so. This low degree of complexation also occurred with a beta-mannan containing alternate (1-->3)- and (1-->4)-linkages and an alginate having beta-ManpA blocks.

Structural and biological features of a hydrogel from seed coats of Chorisia speciosa.

Seed coats from Chorisia speciosa form a hydrogel on contact with water. When the hydrogel was solubilized and the solution centrifuged, subsequent ethanol precipitation gave a polysaccharide (F-I) composed of rhamnose, galactose and uronic acid in a molar ratio of 25:44:31. Analysis of F-I by HPSEC-MALLS showed a homogenous polymer with high molecular weight.