A WATER-SOLUBLE GALACTOMANNAN FROM COCONUT (COCOS NUCIFERA): PART I. METHYLATION STUDIES

1961 ◽  
Vol 39 (2) ◽  
pp. 375-381 ◽  
Author(s):  
C. V. N. Rao ◽  
D. Choudhury ◽  
P. Bagchi
Keyword(s):  
Cocos Nucifera ◽  
Periodate Oxidation ◽  
Water Soluble ◽  
Soluble Polysaccharide ◽  
Structural Significance

A water-soluble polysaccharide isolated from the kernel of coconut (Cocos nucifera) had [α]D −85° and contained D-galactose (1 mole) and D-mannose (2 moles). Methylation and hydrolysis yielded 2,3,4,6-tetra-O-methyl-D-mannose (0.51 mole); 2,3,4,6-tetra-O-methyl-D-galactose (0.5 mole); 2,3,6-tri-O-methyl-D-mannose (5.52 moles); 2,3,6-tri-O-methyl-D-galactose (1.51 moles); and a di-O-methyl-D-galactose (1 mole). These data agree with those of periodate oxidation. The structural significance of these results is discussed.

scholarly journals Characterization of two cell-wall polysaccharides from Fusicoccum amygdali

1971 ◽  
Vol 125 (2) ◽  
pp. 473-480 ◽  
Author(s):  
M. A. Obaidah ◽  
K. W. Buck
Keyword(s):  
Cell Wall ◽  
Sodium Hydroxide ◽  
Periodate Oxidation ◽  
Water Soluble ◽  
Methylation Analysis ◽  
Cell Wall Polysaccharides ◽  
Partial Acid Hydrolysis ◽  
Polysaccharide Fraction ◽  
Linear Chains ◽  
Soluble Polysaccharide

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.

THE WATER-SOLUBLE POLYSACCHARIDES OF DERMATOPHYTES: III. A GALACTOMANNAN FROM TRICHOPHYTON INTERDIGITALE

1964 ◽  
Vol 42 (12) ◽  
pp. 2862-2871 ◽  
Author(s):  
F. Blank ◽  
M. B. Perry
Keyword(s):  
Formic Acid ◽  
Acid Hydrolysis ◽  
Copper Complex ◽  
Periodate Oxidation ◽  
Water Soluble ◽  
Mild Acid Hydrolysis ◽  
Trichophyton Interdigitale ◽  
Soluble Polysaccharide ◽  
Hydrolysis Of ◽  
Mild Acid

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.

STRUCTURE OF AN ARABOGALACTAN FROM WHITE SPRUCE (PICEA GLAUCA (MOENCH) VOSS)

1958 ◽  
Vol 36 (5) ◽  
pp. 755-762 ◽  
Author(s):  
G. A. Adams
Keyword(s):  
Picea Glauca ◽  
Periodate Oxidation ◽  
White Spruce ◽  
Water Soluble ◽  
Molar Ratio ◽  
Glycosidic Bonds ◽  
Spruce Wood ◽  
Soluble Polysaccharide ◽  
Branched Structure ◽  
Hydrolysis Of

A water-soluble polysaccharide isolated from white spruce wood contained D-galactose, L-arabinose, and D-xylose in a molar ratio of 21:3:1. Hydrolysis of the fully methylated polysaccharide yielded 2,3,5-tri-O-methyl-L-arabinose (12 moles); 2,3,4,6-tetra-O-methyl-D-galactose (29 moles); 2,3,4-tri-O-methyl-D-galactose (34 moles); 2,6-di-O-methyl-D-galactose (0.5 moles); 2,4-di-O-methyl-D-galactose (45 moles); 2,3-di-O-methyl-D-xylose (5 moles); and monomethyl xylose (1 mole). When oxidized by periodate the polysaccharide consumed 1.18 moles of oxidant, and yielded 0.56 moles of formic acid per mole of anhydro-D-galactose. The D-xylose was attributed to the presence of a xylan mixed with the arabogalactan in the original polysaccharide preparation. The methylation and periodate oxidation data showed that the arabogalactan possessed a highly branched structure with the anhydro-D-galactose units being joined by 1 → 3 and 1 → 6 glycosidic bonds. All of the L-arabinose was present in the furanoside form as non-reducing terminal units.

CONSTITUTION OF THE GALACTOMANNAN FROM THE KERNEL OF GREEN PALMYRA PALM NUT (BORASSUS FLABELLIFER LINN.)

1961 ◽  
Vol 39 (7) ◽  
pp. 1408-1418 ◽  
Author(s):  
A. K. Mukherjee ◽  
D. Choudhury ◽  
P. Bagchi
Keyword(s):  
Periodate Oxidation ◽  
Structural Formula ◽  
Water Soluble ◽  
Molar Ratio ◽  
Partial Hydrolysis ◽  
Soluble Polysaccharide ◽  
Hydrolysis Of

The water-soluble polysaccharide extracted from the kernel of green palmyra palm nut (Borassusflabellifer Linn.) was shown to be composed of D-galactose and D-mannose in the proportion of 1:2.4. Hydrolysis of the fully methylated galactomannan yielded 2,3,4,6-tetra-O-methyl-D-galactose, 2,3,6-tri-O-methyl-D-mannose, and 2,3-di-O-methyl-D-mannose in the molar ratio of 1:1.4:0.95. Partial hydrolysis of the galactomannan afforded 4-O-β-D-mannopyranosyl-D-mannose, 6-O-α-D-galactopyranosyl-D-mannose, and two trisaccharides. Based on these results a structural formula for the galactomannan has been proposed, additional evidence for which was adduced from periodate-oxidation studies.

Characterization and Suppressive Effect of Astragalus Polysaccharide in Glomerulonephritis Rats

2012 ◽  
Vol 554-556 ◽  
pp. 1713-1716 ◽  
Author(s):  
Shi Gang Li ◽  
Yong Qi Zhang
Keyword(s):  
Structural Characteristics ◽  
Average Molecular Weight ◽  
Periodate Oxidation ◽  
Gel Permeation Chromatography ◽  
Suppressive Effect ◽  
Protein Quantification ◽  
Water Soluble ◽  
Hot Water ◽  
Morphological Observation ◽  
Soluble Polysaccharide

A water-soluble polysaccharide named as APS was isolated from the roots of Astragalus membranaceus by hot water extraction, anion-exchange and gel-permeation chromatography and tested for its renal protective effect. Its structural characteristics were investigated by FTIR, AMLC, NMR spectroscopy, GLC–MS, methylation analysis, periodate oxidation and Smith degradation. Based on the data obtained, APS was found to be a α - (1-4)-D -glucan, with a single α- D-glucose at the C-6 position every nine residue, on average, along the main chain. The glucan has a weight-average molecular weight of about 3.6×104 Da. 24h Urine protein quantification and morphological observation, NF-κB protein expression and IL-2, IL-6 and TNF- α concentrations were significantly decreased by APS treatment, clearly suggesting that APS is effective in protecting against glomerulonephritis induced by C-BSA through the inhibition of NF- κB mediated-cytokine pathway.

Molecular, rheological and physicochemical characterisation of puka gum, an arabinogalactan-protein extracted from the Meryta sinclairii tree

2020 ◽  
Author(s):  
MSM Wee ◽  
Ian Sims ◽  
KKT Goh ◽  
L Matia-Merino
Keyword(s):  
Hydrodynamic Radius ◽  
Average Molecular Weight ◽  
Gum Arabic ◽  
Water Soluble ◽  
Arabinogalactan Protein ◽  
Type Ii ◽  
Weight Average Molecular Weight ◽  
Soluble Polysaccharide ◽  
Physicochemical Characterisation ◽  
Increasing Temperature

© 2019 Elsevier Ltd A water-soluble polysaccharide (type II arabinogalactan-protein) extracted from the gum exudate of the native New Zealand puka tree (Meryta sinclairii), was characterised for its molecular, rheological and physicochemical properties. In 0.1 M NaCl, the weight average molecular weight (Mw) of puka gum is 5.9 × 106 Da with an RMS radius of 56 nm and z-average hydrodynamic radius of 79 nm. The intrinsic viscosity of the polysaccharide is 57 ml/g with a coil overlap concentration 15% w/w. Together, the shape factor, p, of 0.70 (exponent of RMS radius vs. hydrodynamic radius), Smidsrød-Haug's stiffness parameter B of 0.031 and Mark-Houwink exponent α of 0.375 indicate that the polysaccharide adopts a spherical conformation in solution, similar to gum arabic. The pKa is 1.8. The polysaccharide exhibits a Newtonian to shear-thinning behaviour from 0.2 to 25% w/w. Viscosity of the polysaccharide (1 s−1) decreases with decreasing concentration, increasing temperature, ionic strength, and at acidic pH.

Glucan isolated from leaves of Althaea officinalis L.

1983 ◽  
Vol 48 (7) ◽  
pp. 2082-2087 ◽  
Author(s):  
Alžbeta Kardošová ◽  
Jozef Rosík ◽  
Rudolf Toman ◽  
Peter Capek
Keyword(s):  
Medicinal Plant ◽  
Periodate Oxidation ◽  
Linear Structure ◽  
Water Soluble ◽  
Partial Hydrolysis ◽  
Methylation Analysis ◽  
Glycosidic Bonds ◽  
Nmr Data ◽  
Althaea Officinalis ◽  
C Nmr

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.

THE WATER-SOLUBLE POLYSACCHARIDES OF DERMATOPHYTES: IV. GALACTOMANNANS I FROM TRICHOPHYTON GRANULOSUM, TRICHOPHYTON INTERDIGITALE, MICROSPORUM QUINCKEANUM, TRICHOPHYTON RUBRUM, AND TRICHOPHYTON SCHÖNLEINII

1965 ◽  
Vol 43 (1) ◽  
pp. 30-39 ◽  
Author(s):  
C. T. Bishop ◽  
M. B. Perry ◽  
F. Blank ◽  
F. P. Cooper
Keyword(s):  
Aqueous Solutions ◽  
Copper Complexes ◽  
Trichophyton Rubrum ◽  
Periodate Oxidation ◽  
Structural Features ◽  
Water Soluble ◽  
Major Constituent ◽  
Branch Points ◽  
Terminal Units ◽  
Hydrolysis Of

A group of polysaccharides, called galactomannans I, were precipitated as their insoluble copper complexes from aqueous solutions of the crude polysaccharides obtained from each of the organisms designated in the title. The five galactomannans I were homogeneous under conditions of electrophoresis and ultracentrifugation and had high positive specific rotations. The major constituent monosaccharide was D-mannose; amounts of D-galactose ranged from nil for the polysaccharide from T. rubrum to 13% for that from T. schönleinii. Methylation and hydrolysis of the five galactomannans I yielded varying amounts of the following: 2,3,5,6-tetra-O-methyl-D-galactose (not present in the products from T. rubrum), 2,3,4,6-tetra-O-methyl-D-mannose, 2,3,4-tri-O-methyl-D-mannose, 2,4,6-tri-O-methyl-D-mannose, 3,4-di-O-methyl-D-mannose, and 3,5-di-O-methyl-D-mannose. Periodate oxidation results agreed with the methylation studies. The gross structural features of each galactomannan I appear to be the same, namely, a basic chain of 1 → 6 linked α-D-mannopyranose units for approximately every 22 of which there is a 1 → 3 linked α-D-mannopyranose residue. Branch points occur along the 1 → 6 linked chain at the C2 positions of the D-mannopyranose units and once in every 45 units at the C2 position of a 1 → 6 linked D-mannofuranose residue. The D-galactose in the polysaccharides is present exclusively as non-reducing terminal furanose units; non-reducing terminal units of D-mannopyranose are also present. The variations in the identities and relative amounts of the non-reducing terminal units were the only apparent differences in the gross structural features within this group of polysaccharides.

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