THE STRUCTURE OF THE "GUM ASAFOETIDA" POLYSACCHARIDE

1961 ◽  
Vol 39 (1) ◽  
pp. 192-202 ◽  
Author(s):  
J. K. N. Jones ◽  
G. H. S. Thomas
Keyword(s):  
Methyl Ether ◽  
Glucuronic Acid ◽  
Side Chains ◽  
Branched Polymer

The polysaccharide from gum asafoetida contains D-galactose, L-arabinose, L-rhamnose, 4-O-methyl-D-glucuronic acid, and D-glucuronic acid. It is a highly branched polymer which contains a backbone of D-galactopyranose residues which are very probably mainly 1,3-β-linked.The side chains consist of residues of L-arabinofuranose, D-galactopyranose, D-glucuronic acid, and its 4-O-methyl ether.

Mechanical properties of temperature-responsive gels containing ethylene glycol in their side chains

Soft Matter ◽  
2020 ◽  
Vol 16 (48) ◽  
pp. 10946-10953
Author(s):  
Takuma Kureha ◽  
Kyohei Hayashi ◽  
Xiang Li ◽  
Mitsuhiro Shibayama
Keyword(s):  
Mechanical Properties ◽  
Ethylene Glycol ◽  
Methyl Ether ◽  
Biomedical Engineering ◽  
Side Chains ◽  
Dynamic Viscoelasticity ◽  
Temperature Responsive ◽  
Responsive Gels ◽  
Glycol Methyl Ether

The mechanical properties of temperature-responsive poly(oligo-ethylene glycol methyl ether methacrylate)-based gels were investigated using dynamic viscoelasticity measurements to find applications in tissue and biomedical engineering.

Structural Analysis of an Acidic Polysaccharide from Tremella mesenterica NRRL Y-6158

1973 ◽  
Vol 51 (3) ◽  
pp. 219-224 ◽  
Author(s):  
C. G. Fraser ◽  
H. J. Jennings ◽  
P. Moyna
Keyword(s):  
Structural Analysis ◽  
Culture Medium ◽  
Glucuronic Acid ◽  
Side Chains ◽  
Methylation Analysis ◽  
Acidic Polysaccharide ◽  
Molar Ratios ◽  
Limited Variation ◽  
Branched Structure ◽  
End Group

An acidic polysaccharide has been isolated from the culture medium of T. mesenterica NRRL Y-6158. The heteropolymer contained D-xylose, D-mannose, D-glucuronic acid, and O-acetyl in the molar ratios of 7:5:1:0.7, respectively. Methylation analysis of the heteropolymer indicated that it was essentially a 1 → 3-α-linked mannopyranose backbone having approximately 80% of the backbone units substituted, thus forming a very highly branched structure. The substituents on the backbone were found to be D-glucopyranosyluronic acid end-group, β-linked to the O-2 positions of the mannopyranose units, and 2-O-β-D-linked xylopyranose side-chains, linked both to the O-2 and O-4 positions of the mannopyranose backbone. The methylation analysis suggests that these side-chains are probably two or three xylopyranose units long, although a limited variation in the length of the side-chains is a possibility.

scholarly journals Isolation and characterization of dermatan sulphate proteoglycans from bovine sclera

1981 ◽  
Vol 193 (1) ◽  
pp. 143-153 ◽  
Author(s):  
L Cöster ◽  
L A Fransson
Keyword(s):  
Sodium Acetate ◽  
Glucuronic Acid ◽  
Guanidine Hydrochloride ◽  
Sodium Dodecyl ◽  
Gel Chromatography ◽  
Side Chains ◽  
Dermatan Sulphate ◽  
Specific Chemical ◽  
Protein Core ◽  
Isolation And Characterization

1. Proteoglycans were extracted from sclera with 4 M-guanidine hydrochloride in the presence of proteinase inhibitors and purified by ion-exchange chromatography and density-gradient centrifugation. 2. The entire proteoglycan pool was characterized by compositional analyses and by specific chemical (periodate oxidation) and enzymic (chondroitinases) degradations. The glycan moieties of the molecules were exclusively galactosaminoglycans (dermatan sulphate-chondroitin sulphate co-polymers). In addition, the preparations contained small amounts of oligosaccharides. 3. The scleral proteodermatan sulphates were fractionated into one larger (I) and one smaller (II) component by gel chromatography. Proteoglycan I was eluted in a more excluded position on gel chromatography in 0.5 M-sodium acetate than in 4.0 M-guanidine hydrochloride. Reduced and alkylated proteoglycan I was eluted in the same position (in 0.5 M-sodium acetate) as was the starting material (in 4.0 M-guanidine hydrochloride). The elution position of proteoglycan II was the same in both solvents. Proteoglycans I and II had s0 20,w values of 2.8 × 10(-13) and 2.2 × 10(-13) s respectively in 6.0 M-guanidine hydrochloride. 4. The two proteoglycans differed with respect to the nature of the protein core and the co-polymeric structure of their side chains. Also proteoglycan I contained more side chains than did proteoglycan II. The dermatan sulphate side chains of proteoglycan I were D-glucuronic acid-rich (80%), whereas those of proteoglycan II contained equal amounts of D-glucuronic acid and L-iduronic acid. Furthermore, the co-polymeric features of the side chains of proteoglycans I and II were different. The protein core of proteoglycan I was of larger size than that of proteoglycan II. The latter had an apparent molecular weight of 46 000 (estimated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis), whereas the former was greater than 100 000. In addition, the amino-acid composition of the two core preparations was different. 5. As proteoglycan I altered its elution position on gel chromatography in 4 M-guanidine hydrochloride compared with 0.5 M-sodium acetate it is proposed that a change in conformation or a disaggregation took place. If the latter hypothesis is favoured, aggregation may be due to self-association or mediated by an extrinsic molecule, e.g. hyaluronic acid.

scholarly journals Crystal structure of Dehydrodieugenol B methyl ether, a neolignan from Nectandra leucantha Nees and Mart (Lauraceae)

2018 ◽  
Vol 74 (4) ◽  
pp. 518-521
Author(s):  
Simone S. Grecco ◽  
Gerold Jerz ◽  
Joao Henrique G. Lago ◽  
Peter G. Jones
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Dihedral Angle ◽  
Methyl Ether ◽  
Title Compound ◽  
Side Chains ◽  
Stacking Interactions ◽  
Aromatic Rings ◽  
Torsion Angles ◽  
Compound C

In the title compound, C21H24O4 (systematic name: 4,5′-diallyl-2,2′,3′-trimethoxydiphenyl ether), the aromatic rings lie almost perpendicular to each other [dihedral angle = 85.96 (2)°]. The allyl side chains show similar configurations, with Car—C—C=C (ar = aromatic) torsion angles of −123.62 (12) and −115.54 (12)°. A possible weak intramolecular C—H...O interaction is observed. In the crystal, molecules are connected by two C—H...O hydrogen bonds, forming undulating layers lying parallel to the bc plane. Weak C—H...π and π–π stacking interactions also occur.

Structure of an acidic polysaccharide elaborated by Bacilluspolymyxa-1231-ATCC 842

1990 ◽  
Vol 68 (2) ◽  
pp. 323-328 ◽  
Author(s):  
Salah M. Abdel-Kader ◽  
Mohamady A. Issa ◽  
Mohamed A. El-Shafei
Keyword(s):  
Acid Hydrolysis ◽  
Glucuronic Acid ◽  
Molar Ratio ◽  
Side Chains ◽  
Partial Acid Hydrolysis ◽  
Acidic Polysaccharide ◽  
Backbone Chain ◽  
Branched Structure

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.

STRUCTURAL RELATIONSHIPS OF EXTRACELLULAR POLYSACCHARIDES FROM PHYTOPATHOGENIC XANTHOMONAS SPP.: PART II. X. HYACINTHI, X. TRANSLUCENS, AND X. MACULOFOLIIGARDENIAE

1963 ◽  
Vol 41 (9) ◽  
pp. 2357-2361 ◽  
Author(s):  
P. A. J. Gorin ◽  
J. F. T. Spencer
Keyword(s):  
Glucuronic Acid ◽  
Extracellular Polysaccharide ◽  
Extracellular Polysaccharides ◽  
Considerable Proportion ◽  
Enzymic Hydrolysis ◽  
Branched Polymer ◽  
Structural Relationships ◽  
Xanthomonas Translucens

The extracellular polysaccharide formed from Xanthomonas hyacinthi is shown to be a branched polymer containing glucuronic acid, mannose, and glucose. Acid and enzymic hydrolysis show the presence of β-D-Glp 1 → 4 D-Man and the 4-unit sequence β-D-GlpA1 → 2 D-Manp 1 → 3 β-D-Glp 1 → 4 D-Gl. Examination by the methylation technique showed the presence of a considerable proportion of 2-linked mannopyranose units. The spectrum of methyl glycosides formed from this polysaccharide and those from Xanthomonas maculofoliigardeniae and Xanthomonas translucens are similar, and in terms of sugar linkages differentiate them from that of Xanthomonas stewartii, which contains glucuronic acid, glucose, and galactose.

CONSTITUTION OF THREE HEMICELLULOSES FROM THE WOOD OF ENGELMANN SPRUCE (PICEA ENGELMANNI)

1963 ◽  
Vol 41 (6) ◽  
pp. 1389-1395 ◽  
Author(s):  
A. R. Mills ◽  
T. E. Timell
Keyword(s):  
Glucuronic Acid ◽  
Water Soluble ◽  
Partial Hydrolysis ◽  
Side Chains ◽  
Engelmann Spruce ◽  
Linear Framework ◽  
Single Side ◽  
Hydrolysis Of ◽  
Picea Engelmanni

An arabino-4-O-methylglucuronoxylan (10:70:12), a water-soluble galactoglucomannan (1:1:3), and an alkali-soluble galactoglucomannan (0.2:1:3) have been isolated in yields of 8.0, 1.0, and 8.1% from the wood of Engelmann spruce (Picea engelmanni). The xylan consisted of a linear framework of (1 → 4)-linked β-D-xylose residues to which were directly attached single side chains of (1 → 2)-linked 4-O-methyl-α-D-glucuronic acid and (1 → 3)-linked α-L-arabinofuranose residues. The galactoglucomannans were both composed of a backbone of (1 → 4)-linked β-D-mannose and β-D-glucose residues, some of which carried directly attached side chains of (1 → 6)-linked α-D-galactopyranose residues. Partial hydrolysis of the water-soluble galactoglucomannan yielded, among other oligosaccharides, a trisaccharide composed of galactose, glucose, and mannose residues. It is concluded that the main polysaccharides in the wood of Engelmann spruce are the same as those in most other gymnosperms. In the bark of this tree, the water-soluble galactoglucomannan is replaced by one or several polysaccharides of an entirely different composition.

scholarly journals Characterization of a Family GH5 Xylanase with Activity on Neutral Oligosaccharides and Evaluation as a Pulp Bleaching Aid

2010 ◽  
Vol 76 (18) ◽  
pp. 6290-6294 ◽  
Author(s):  
Óscar Gallardo ◽  
María Fernández-Fernández ◽  
Cristina Valls ◽  
Susana Valeria Valenzuela ◽  
M. Blanca Roncero ◽  
...  
Keyword(s):  
Kraft Pulp ◽  
Glucuronic Acid ◽  
Side Chains ◽  
Glycosyl Hydrolases ◽  
Pulp Bleaching

ABSTRACT A new bacterial xylanase belonging to family 5 of glycosyl hydrolases was identified and characterized. The xylanase, Xyn5B from Bacillus sp. strain BP-7, was active on neutral, nonsubstituted xylooligosaccharides, showing a clear difference from other GH5 xylanases characterized to date that show a requirement for methyl-glucuronic acid side chains for catalysis. The enzyme was evaluated on Eucalyptus kraft pulp, showing its effectiveness as a bleaching aid.

Surface segregation of a branched polymer with hydrophilic poly[2-(2-ethoxy)ethoxyethyl vinyl ether] side chains

2017 ◽  
Vol 8 (3) ◽  
pp. 505-510 ◽  
Author(s):  
Shin Sugimoto ◽  
Yukari Oda ◽  
Toyoaki Hirata ◽  
Ruriko Matsuyama ◽  
Hisao Matsuno ◽  
...  
Keyword(s):  
Vinyl Ether ◽  
Surface Segregation ◽  
Side Chains ◽  
Branched Polymer ◽  
Preferential Segregation ◽  
Surface Construction

A branched polymer with hydrophilic side chains was designed and prepared for anti-biofouling surface construction through its preferential segregation.

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