Polysaccharides from the Flowers of Malva Mauritiana L.: Structure of an Arabinogalactan

1995 ◽  
Vol 60 (12) ◽  
pp. 2112-2118 ◽  
Author(s):  
Peter Capek ◽  
Alžbeta Kardašová

A water-soluble arabinogalactan composed of D-galactose and L-arabinose in the mole ratio 1 : 1.4 has been isolated from the flowers of Malva mauritiana L. Partial acid hydrolysis, methylation analysis, periodate oxidation, and 13C NMR spectroscopy were employed in structure elucidation. The arabinogalactan was shown to have a highly branched structure. The core consisted of 1,6-linked β-D-galactopyranose units, about 65% of which were substituted in position C-3 by side-chains of mainly 1,5-linked α-L-arabinofuranosyl residues.

1983 ◽  
Vol 48 (7) ◽  
pp. 2082-2087 ◽  
Author(s):  
Alžbeta Kardošová ◽  
Jozef Rosík ◽  
Rudolf Toman ◽  
Peter Capek

A water-soluble low-molecular D-glucan was isolated from leaves of the medicinal plant marsh-mallow (Althaea officinalis L.). The results of methylation analysis, partial hydrolysis, periodate oxidation, and 13C NMR data indicated a virtually linear structure with α-(1→6) glycosidic bonds.


1971 ◽  
Vol 125 (2) ◽  
pp. 473-480 ◽  
Author(s):  
M. A. Obaidah ◽  
K. W. Buck

1. The nature of two polysaccharides (s020 values 6S and 2S respectively in 1m-sodium hydroxide), comprising a fragment (fraction BB, [α]D +236° in 1m-sodium hydroxide), previously isolated from cell walls of Fusicoccum amygdali, has been investigated. 2. Both the major (2S) and minor (6S) components were affected by incubation with α-amylase. The 6S polysaccharide was also attacked by exo-β-(1→3)-glucanase, which is evidence that it contained both α-(1→4)- and β-(1→3)-glucopyranose linkages. By fractionation of the products of α-amylase-treated fraction BB it was possible to obtain a water-insoluble polysaccharide, fraction P ([α]D +290° in 1m-sodium hydroxide, 67% of fraction BB) and a water-soluble polysaccharide, fraction Q ([α]D +16° in 1m-sodium hydroxide, 11% of fraction BB), both of which sedimented as single boundaries with s020 values (in 1m-sodium hydroxide) of 1.7S and 4.6S respectively. 3. Evidence from periodate oxidation, methylation analysis, i.r. spectroscopy and partial acid hydrolysis showed that fraction P consisted of linear chains of α-(1→3)-glucopyranose units with blocks of one or two α-(1→4)-glucopyranose units interspersed at intervals along the main chain. The 2S polysaccharide, from which fraction P is derived, evidently also contains longer blocks of α-(1→4)-glucopyranose units, that are susceptible to α-amylase action. 4. Fraction Q consisted of glucose (88%) with small amounts of galactose, mannose and rhamnose. Evidence from digestion with exo- and endo-β-(1→3)-glucanases, periodate oxidation and methylation analysis suggests that fraction Q consists of a branched galactomannorhamnan core, to which is attached a β-(1→3)-, β-(1→6)-glucan. In the cell wall, chains of α-(1→4)-linked glucopyranose units are linked to fraction Q to form the 6S component of fraction BB.


1980 ◽  
Vol 58 (2) ◽  
pp. 147-153 ◽  
Author(s):  
Carey B. Bottom ◽  
Donald J. Siehr

The alkali-insoluble (R-) fraction from the cell walls of Coprinus macrorhizus var. microsporus is a highly branched glucan, containing α-(1 → 4), β-(1 → 3), and β-(1 → 6) linkages as shown by methylation, partial acid hydrolysis, and enzymic hydrolysis. The α-(1 → 4)-linked segments are joined by occasional β-(1 → 3) links as suggested by the identification of 2-O-α-glucopyranosyl erythritol in the hydrolysate of the reduced, periodate-oxidized glucan. Hydrolysis of the permethylated glucan gave nearly equimolar amounts of 2,4-di- and 2,3-di-O-methyl-D-glucose. Methylation analysis of the residue from enzymic hydrolysis, the "CORE-fraction," indicated the presence of glucose residues in this fraction linked through positions O1, O3, O4, and O6. Hydrolysates of the R-fraction contained mannose, glucosamine, and amino acids in addition to glucose.


1992 ◽  
Vol 47 (10) ◽  
pp. 1444-1458 ◽  
Author(s):  
Roland Ferth ◽  
Andreas Baumann ◽  
Wolfgang Robien ◽  
Brigitte Kopp

From leaves and bulbs of Ornithogalum nutans L. (2 n = 28), seventeen cardenolides were isolated by column chromatography, DCCC and TLC. The structure elucidation was performed by means of 1H NMR, 13C NMR, HH-Cosy, HC-Cosy and FAB-MS studies and identification of the sugar moieties by GLC after acid hydrolysis of the cardenolides. Sugar compounds were identified as digitoxose, 3-acetyl-digitoxose, 2-deoxy-allose, 6-deoxy-allose, rhamnose, xylose and apiose. Glycosides of 7β,15β, 16 α-trihydroxy-uzarigenin, 8β,16 α-dihy-droxy, 15-oxo-uzarigenin, 3 β, 11β-dihydroxy, 12-oxo, 18-nor-5 α-card-13-enolid, 11 α-hydroxygitoxigenin, 12-oxo,8, 14β-epoxy-uzarigenin, 8β-hydroxy, 15-oxo-uzarigenin and 12β-hydroxy-oleandrigenin are described for the first time, the presence of oleandrigenin-glycosides in the genus Ornithogalum was not known until now. Ornithogalum nutans L. shows a different cardenolide pattern from the second European species of the section Myogalum (LINK) PETERM. - Ornithogalum boucheanum (KUNTH) ASCHERS.


1989 ◽  
Vol 67 (6) ◽  
pp. 1038-1050 ◽  
Author(s):  
James C. Richards ◽  
Malcolm B. Perry ◽  
Peter J. Kniskern

The structure of the specific capsular polysaccharide produced by Streptococcuspneumoniae type 22F (American type 22) was investigated by high-field 1H and 13C nuclear magnetic resonance spectroscopy, composition, methylation analysis, and periodate oxidation studies. The polysaccharide was found to be a high molecular weight acidic polymer composed of D-glucose, D-galactose, D-glucuronic acid, and L-rhamnose residues to form a regular repeating hexasaccharide unit having the structure[Formula: see text]in which the β-L-rhamnopyranosyl residues were substituted by O-acetyl groups in 80% of the repeating units. The 1H and 13C nmr resonances of the O-deacetylated type 22F polysaccharide were completely assigned by application of two-dimensional homo- and heteronuclear chemical shift correlation techniques. Keywords: Streptococcuspneumoniae polysaccharide, NMR analysis.


1994 ◽  
Vol 59 (12) ◽  
pp. 2714-2720 ◽  
Author(s):  
Alžbeta Kardošová ◽  
Peter Capek

A rhamnoarabinogalactan isolated from the leaves of Plantago lanceolata L. var. libor has been investigated by methylation analysis, partial hydrolysis, and 13C NMR spectroscopy. The structural conclusions obtained by 13C NMR measurements were consistent with the data from methylation analysis. The polysaccharide has a β-(1→6)-D-galactan core branched on O-3 by side chains of (1→5)-linked α-L-arabinofuranosyl units, some of which bear in position O-5 terminal β-D-galactopyranosyl residues. L-Rhamnose occurs as nonreducing ends.


2013 ◽  
Vol 8 (9) ◽  
pp. 1934578X1300800
Author(s):  
Tsukasa Iwashina ◽  
Minoru N. Tamura ◽  
Yoshinori Murai ◽  
Junichi Kitajima

Two new flavonol glycosides were isolated from the leaves of Triantha japonica, together with eight known flavonols, kaempferol 3- O-sophoroside, kaempferol 3- O-sambubioside, kaempferol 3- O-glucosyl-(1→2)-[glucosyl-(1→6)-glucoside], quercetin 3- O-sophoroside, quercetin 3- O-sambubioside, isorhamnetin 3- O-glucoside, isorhamnetin 3- O-sophoroside and isorhamnetin 3- O-sambubioside. The new compounds were identified as kaempferol 3- O-β-xylopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-glucopyranoside] (1) and isorhamnetin 3- O-β-xylopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-glucopyranoside] (3) by UV, LC-MS, acid hydrolysis, and 1H and 13C NMR spectroscopy. Another two new flavonol glycosides were isolated from the leaves of Tofieldia nuda, and identified as kaempferol 3- O-β-glucopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-galactopyranoside] (4) and quercetin 3- O-β-glucopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-galactopyranoside] (5). Though the genera Triantha and Tofieldia were treated as Tofieldia sensu lato, they were recently divided into two genera. It was shown by this survey that their flavonoid composition were also different to each other.


1964 ◽  
Vol 42 (12) ◽  
pp. 2862-2871 ◽  
Author(s):  
F. Blank ◽  
M. B. Perry

The water-soluble polysaccharide preparation from Trichophytoninterdigitale was fractionated to give two distinct galactomannans and a glucan. A galactomannan isolated via its insoluble copper complex had [α]D +75° (water) and was composed of D-galactose (12%) and D-mannose (88%). On periodate oxidation, the galactomannan consumed 1.73 mole periodate and released 0.67 mole formic acid and 0.12 mole formaldehyde per anhydrohexose unit. Hydrolysis of the methylated galactomannan gave 2,3,5,6-tetra-O-methyl-D-galactose (1 part), 2,3,4,6-tetra-O-methyl-D-mannose (1 part), 2,3,4-tri-O-methyl-D-mannose (4 parts), and3,4-di-O-methyl-D-mannose (2 parts). Mild acid hydrolysis of the galactomannan removed all the galactose residues, leaving a mannan having [α]D +84° (water) whose structure was analyzed by periodate oxidation and methylation techniques.


1990 ◽  
Vol 68 (2) ◽  
pp. 323-328 ◽  
Author(s):  
Salah M. Abdel-Kader ◽  
Mohamady A. Issa ◽  
Mohamed A. El-Shafei

An extracellular acidic polysaccharide, elaborated by Bacilluspolymyxa, was composed of D-glucose, D-mannose, D-galactose, and D-glucuronic acid (approximate molar ratio of 4:3:1:1). Methylation and fragmentation analysis by partial acid hydrolysis indicated that the polysaccharide had a complicated, highly branched structure, consisting mainly of β(1 → 3) and (1 → 4) D-glycosidic linkages. The backbone chain containing D-glucose, D-mannose, and D-glucuronic acid residues is attached at the C-4, C-3, and C-4 positions, respectively, one out of every three glucose residues being substituted at the C-2 position to form two kinds of branches at the C-2 and C-4 positions, with side chains of single or a few carbohydrate units that are terminated by D-glucose and (or) D-mannose residues. Keywords: acidic polysaccharide, Bacilluspolymyxa.


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