Galactomannan from Ambiguous Crazyweed (Oxytropis ambigua(Pall.) DC)

A galactomannan with a molecular weight of 735 kDa was first isolated and purified from seeds of ambiguous crazyweed Oxytropis ambigua(Pall) DC (family Leguminosae) with a yield of 3.6%. Its aqueous solutions displayed an optical activity ([] _D = 73.32°) and high viscosity ([] = 644 ml/g). Chemical analysis and ¹³C-NMR spectroscopy revealed the presence of D-mannopyranose and D-glucopyranose in the heteropolysaccharide at a molar ratio of 1.39 : 1. The linear backbone of its macromolecule consists of 1,4--D-mannopyranose residues. Single -D-galactose residues substitute 72% of the mannoses to form branches.     

Study of galactoglucomannans from the seed of Cercis canadensis L

Galactoglucomannans were isolated by selective precipitation from aqueous and alkaline extracts of endosperm and hulls of Cercis canadensis, a member of the family Fabaceae. Their monosaccharide composition (Man: Gal: Glu) was as follows: 10.4: 0.9: 1 (polysaccharide from the endosperm) and 4.5: 0.9: 1 (polysaccharide from the hulls). The identity of IR spectra was indicative of the commonness of their structure. Analysis of the structure of the galactoglucomannan from endosperm by 13C NMR spectroscopy showed that its main chain consisted of 1,4-beta-D-manno- and 1,4-beta-D-glucopyranose. Part of mannose residues in the chain were substituted at C6 with single residues of alpha-D-galactopyranose. Galactoglucomannans are located in different part of the seed and implement different functions.     

Study of galactoglucomannans from the seed of <Emphasis Type="Italic">Cercis canadensis</Emphasis> L.

Galactoglucomannans were isolated by selective precipitation from aqueous and alkaline extracts of endosperm and hulls of Cercis canadensis, a member of the family Fabaceae. Their monosaccharide composition (Man : Gal : Glu) was as follows: 10.4 : 0.9 : 1 (polysaccharide from the endosperm) and 4.5 : 0.9 : 1 (polysaccharide from the hulls). The identity of IR spectra was indicative of the similarity of their structure. Analysis of the structure of the galactoglucomannan from endosperm by ¹³C NMR spectroscopy showed that its main chain consisted of 1,4--D-manno- and 1,4--D-glucopyranose. Part of the mannose residues in the chain were substituted at C6 with single residues of -D-galactopyranose. Galactoglucomannans are located in different parts of the seed and implement different functions.__________Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 3, 2005, pp. 324–329.Original Russian Text Copyright © 2005 by Mestechkina, Egorov, Anulov, Shcherbukhin.     

Anticoagulant activity of low-molecular-weight sulfated derivatives of galactomannan from Cyamopsis tetragonoloba (L.) seeds

Galactomannan from seeds of Cyamopsis tetragonoloba (L.) Taub. (guar) was depolymerized using immobilized enzymatic preparation celloviridin. A set of fragments whose molecular weights varied from 12.6 to 245.6 kDa was obtained. Sulfated derivatives of components of all fractions were synthesized, in which the content of HSO3(-) groups was 48.05% +/- 2.31. All preparations exhibited anticoagulant activity, which was recorded in vitro in two tests--aIIa and aXa. The antithrombin activity (aIIa) was high (up to 65-87 U/mg) and did not depend on the molecular weight of a sulfated derivative; in the second test (aXa), the effect of molecular weight was observed. Biospecific electrophoresis allowed us to detect the ability of galactomannan sulfates to form complexes with protamine sulfate, a classic antidote to heparin.     

Determination of the Primary and Fine Structures of a Galactomannan from the Seed of Gleditsia triacanthos f. inermis L.

Galactomannan, a polysaccharide with a molecular weight of 660 kDa, was isolated for the first time from the seed of Gleditsia triacanthos f. inermis (yield, 15.4%). Its aqueous solutions were optically active ([] _D = +31.0°) and highly viscous ([] = 578 ml/g). Analysis of this heteropolysaccharide using chemical, enzymatic, and chromatographic procedures, as well as IR and ¹³C NMR spectroscopy, showed that it consists of D-mannopyranose and D-galactopyranose residues (molar ratio, 2.42 : 1). The main chain of this galactomannan comprises 1,4--D-mannopyranose residues, 41% of which are substituted at C6 with single residues of -D-galactopyranose. The probability of occurrence in the chain of mannobiose units substituted otherwise, determined experimentally, was 0.16 for the Man–Man unit, 0.50 for the Gal(Man–Man) and (Man–Man)Gal units, and 0.34 for the disubstituted Gal(Man–Man)Gal unit.     

Aspartate and alanine aminotransferase activity in the tissues of adrenalectomized rabbits following administration of hydrocortisone and corticotropin

Aspartate and alanine aminotransferase (AsT, AlT) activities were studied in tissues of adrenalectomized rabbits which were treated with a single and multiple administrations of hydrocortisone (5 mg/kg) or a single administration of corticotropine (ACTH, 10 units/kg). It is shown that adrenalectomy decreases the AsT activity in homogenate of femoral muscle tissue and decreases the AlT activity in homogenate and supernatant of the liver, spleen and muscle tissue and in blood plasma. A single administration of hydrocortisone increases the AsT activity in supernatant of femoral muscle tissue and in blood plasma and increases AIT activity in the brain, liver, muscle and blood plasma. Parallel with that AsT and AlT activities are decreased in the spleen tissue. Multiple administration of hydrocortisone induces analogous changes in the AsT activity in the muscle and in the AlT activity in the liver, muscle and blood plasma. A single administration of ACTH induces an increase of the AsT activity in the muscle supernatant and in blood plasma. It also causes a rise of the AlT activity in the liver, muscle supernatant and blood plasma. The AlT activity is decreased in the brain supernatant. A question about stability of free amino acids metabolism (especially of alanine and aspartic acid) in the rabbit brain with changes in corticosteroid levels of organism is under discussion.     

Composition and structure of a galactomannan macromolecules from seeds of Astragalus lehmannianus Bunge

The composition and structure of a galactomannan from seeds of Astragalus lehmannianus, an endemic legume species, is reported for the first time. The purified galactomannan (yield, 4.8%) contained 55% D-mannose and 45% D-galactose and had a molecular weight of 997.03 kDa. Its aqueous solutions were optically active and highly viscous (the specific rotation, [alpha]D, equaled +81.3 degrees; the characteristic viscosity, [eta], 868.4 ml/g). Chemical, chromatographic, and spectral (IR and 13C-NMR spectroscopy) methods were used to demonstrate that the main chain of the molecule is formed by residues of 1,4-beta-D-mannopyranose, 78% of which are substituted at position 6 with single alpha-D-galactopyranose. The distribution of galactose along the chain was calculated from NMR spectra: frequencies of occurrence, per pair of neighboring mannose units, of (1) two substituents, (2) one substituent, and (3) no substituents were 65.3, 31.5, and 3.2%, respectively. The specific rotation of galactomannans was shown to correlate with their content of galactose.     

The Structure and Characteristics of Glucomannans from Eremurus iaeand E. zangezuricus: Assignment of Acetyl Group Localization in Macromolecules

Water-soluble glucomannans from roots of Eremurus iaeand E. zangezuricuswere studied. These polysaccharides were shown to contain 28.8, 69.0, and 2.2% (E. iae) and 22.6, 74.8, and 2.6% (E. zangezuricus) D-glucose, D-mannose and acetyl groups, respectively. Their IR spectra were identical and revealed the presence of 1,4--glycosidic bonds and ester carbonyl groups. ¹³C-NMR spectroscopy revealed both polysaccharides to be linear partially acetylated 1,4--D-glucomannans. Acetyl groups substituted C2- and C3-hydroxyls of mannopyranose residues. A comparison of ¹³C-NMR data and the results of correlation analysis suggested that acetyl groups can substitute no more than one OH-group in the mannopyranosyl residue. The estimated values of [] _D , [], and molecular weights (MW) were –34.0°, 6.05 dl/g, and 265.5 kDa, respectively, for E. iaepolysaccharide, and –38.2°, 5.4 dl/g, and 233.5 kDa, respectively, for E. zangezuricuspolysaccharide. A correlation between the intrinsic viscosities of polysaccharides and their molecular weight determined by HPLC was revealed.     

Anticoagulant activity of low-molecular-weight sulfated derivatives of galactomannan from <Emphasis Type="Italic">Cyamopsis tetragonoloba</Emphasis> (L.) seeds

Galactomannan from seeds of Cyamopsis tetragonoloba (L.) Taub. (guar) was depolymerized using immobilized enzymatic preparation celloviridin. A set of fragments whose molecular weights varied from 12.6 to 245.6 kDa was obtained. Sulfated derivatives of components of all fractions were synthesized, in which the content of HSO ₃ ^? groups was 48.05 ± 2.31%. All preparations exhibited anticoagulant activity, which was recorded in vitro in two tests—alla and aXa. The antithrombin activity (aIIa) was high (up to 65–87 U/mg) and did not depend on the molecular weight of a sulfated derivative; in the second test (aXa), the effect of molecular weight was observed. Biospecific electrophoresis allowed us to detect the ability of galactomannan sulfates to form complexes with protamine sulfate, a classic antidote to heparin.     

Composition and structure of galactomannan from the seed of Gleditsia ferox Desf

Galactomannan, a heteropolysaccharide with a molecular weight of 1660 kDa, was isolated form the seed of Gleditsia ferox Desf., introduced in Russia, with a yield of 18.9%. Its aqueous solutions were optically active ([alpha]D = +30.5 degrees) and highly viscous ([eta] = 1430 ml/g). Analysis of the heteropolysaccharide using chemical, enzymatic, and chromatographic procedures showed that it consists of D-mannopyranose and D-galactopyranose residues (molar ratio, 2.54:1). The main chain of this galactomannan consists of 1,4-beta-D-mannopyranose residues, 39.2% of which are substituted at C6 with single residues of alpha-D-galactopyranose. The probability of occurrence of mannobiose units differentially substituted with galactose was determined by 13C-NMR data and equaled, respectively, 0.37, 0.47, and 0.16 for non-substituted Man-Man units, monosubstituted Gal(Man-Man) and (Man-Man)Gal units taken together, and for the disubstituted Gal(Man-Man)Gal units.