PERIODATE OXIDATION OF MESQUITE GUM

1963 ◽  
Vol 41 (6) ◽  
pp. 1417-1423 ◽  
Author(s):  
G. G. S. Dutton ◽  
A. M. Unrau
Keyword(s):  
Periodate Oxidation ◽  
Oxidation Reduction ◽  
Acidic Fraction ◽  
Mild Hydrolysis ◽  
Mesquite Gum ◽  
Glycerol Residue

Mesquite gum was subjected to the Smith procedure involving periodate oxidation, reduction, and mild hydrolysis. The main D-galactose chain was fragmented to a greater extent than expected. The quantity of glycerol formed indicated the presence of a considerable number of 1 → 6 linkages while the formation of threitol showed the presence of 1 → 4 linkages. Several small oligosaccharides terminated by a glycerol residue were isolated together with an oligosaccharide of D.P. 30. Further periodate oxidation of the latter gave a product with D.P. 24 which was in turn oxidized to a compound consisting largely of D-galactose and glycerol. Reduction of the acidic fraction gave mainly 2-O-methyl-D-erythritol.

Studies of a Quinyl-p-coumarate in the Pineapple Plant (Ananas comosus var. cayenne)

1959 ◽  
Vol 12 (2) ◽  
pp. 240 ◽  
Author(s):  
GK Sutherland ◽  
WA Gortner
Keyword(s):  
Indoleacetic Acid ◽  
Spectral Characteristics ◽  
Periodate Oxidation ◽  
Quinic Acid ◽  
Ananas Comosus ◽  
Acid Oxidase ◽  
Coumaric Acid ◽  
Indoleacetic Acid Oxidase ◽  
Acid Lactone ◽  
Mild Hydrolysis

An ester is found in small concentrations in vegetative pineapple plants, with spectral characteristics in the ultraviolet of an ester of p-coumaric acid. p-Coumaric acid is obtained after hydrolysis, and the remaining aqueous hydrolysate indicates the presence of quinic acid lactone on chromatograms. On the basis of neutral equivalent determinations, boric acid conductivity and periodate oxidation experiments, and analyses following mild hydrolysis, the structure of the ester is suggested to be a quinyl-di-p-coumarate. It serves in the plant as a cofactor for pineapple indoleacetic acid oxidase.

THE STRUCTURE OF LINSEED MUCILAGE: PART II

1962 ◽  
Vol 40 (7) ◽  
pp. 1266-1279 ◽  
Author(s):  
K. Hunt ◽  
J. K. N. Jones
Keyword(s):  
Galacturonic Acid ◽  
Main Chain ◽  
Periodate Oxidation ◽  
Neutral Fraction ◽  
Acetate Solution ◽  
Partial Acid Hydrolysis ◽  
Cupric Acetate ◽  
Acidic Fraction ◽  
Degraded Material ◽  
Hydrolysis Of

Linseed mucilage has been separated into an acidic and a neutral fraction. The acidic fraction was further separated, by the use of cupric acetate solution, into two fractions, CuI and CuII. Fraction CuI contained L-rhamnose, L-galactose, and D-galacturonic acid. The methylated reduced polysaccharide gave on hydrolysis 2,3,4-tri-O-methyl-L-rhamnose, 3,4-di-O-methyl-L-rhamnose, 4-O-methyl-L-rhamnose, 2,3,4,6-tetra-O-methyl-D-galactose, 2,3,6-tri-O-methyl-D-galactose, and 2,3-di-O-methyl-D-galactose (?); L-galactose was lost during the methylation process. Periodate oxidation studies on the material indicated that the polymer was composed of a main chain of L-rhamnose units with most of the L-galactose units attached as non-reducing end groups. Fraction CuII contained L-rhamnose, L-fucose, L-galactose, and D-galacturonic acid. The methylated reduced polysaccharide gave on hydrolysis 2,3,4-tri-O-methyl-L-fucose, 2,3,4,6-tetra-O-methyl-L-galactose, 2,3,6-tri-O-methyl-D-galactose, 4-O-methyl-L-rhamnose, L-rhamnose, and possibly 2,3-di-O-methyl-D-galactose and 3-O-methyl-D-galactose. Periodate oxidation studies and a degradation by the Smith procedure indicated the presence of a L-rhamnose backbone with L-fucose and L-galactose units attached as non-reducing end groups.The neutral fraction yielded a periodate-oxidizable material after one Smith-type degradation. Periodate oxidation studies indicated that the degraded material was branched. Methylation of the degraded polysaccharide followed by hydrolysis yielded 2,3,4-tri-O-methyl-D-xylose, 2,3-di-O-methyl-D-xylose, 2,4-di-O-methyl-D-xylose, 4-O-methyl-D-xylose, D-xylose, and traces of 2,3,4-trt-O-methyl- or 2,5-di-O-methyl-L-arabinose, 2,4-di-O-methyl-D-xylose, and 3-O-methyl-D-xylose. The main backbone of the degraded polysaccharide appeared to consist of (1 → 4)-linked D-xylose units. Linkages of the (1 → 3) type were also present. The smaller fragments from the Smith-type degradation, L-arabinose, 2-O-α-L-arabinosyl glycerol, and glycerol were characterized. A partial acid hydrolysis of the neutral fraction yielded a number of oligosaccharides.

GUM JEOL: THE STRUCTURE OF THE DEGRADED GUM DERIVED FROM IT

1964 ◽  
Vol 42 (1) ◽  
pp. 107-112 ◽  
Author(s):  
A. K. Bhattacharyya ◽  
C. V. N. Rao
Keyword(s):  
Acid Hydrolysis ◽  
Galacturonic Acid ◽  
Uronic Acid ◽  
Periodate Oxidation ◽  
Neutral Fraction ◽  
Partial Structure ◽  
Mild Acid Hydrolysis ◽  
Acidic Fraction ◽  
Hydrolysis Of ◽  
Mild Acid

Gum Jeol has been shown to be composed of residues of D-galactose, L-arabinose, and D-galacturonic acid. On mild acid hydrolysis the gum gave an aldobiouronic acid, viz. 3-O-(D-galactopyranosyl uronic acid)-D-galactopyranose. Hydrolysis of the fully methylated degraded gum yielded 2,3,4,6-terra-(3 moles); 2,3,4-tri-(2 moles); 2,4-di-(1 mole); and 2-O-methyl-D-galactose (1 mole) in the neutral fraction of the hydrolyzate. The reduced acidic fraction yielded 2,3,4-tri-(2 moles) and 2,4-di-O-methyl-D-galactose (2 moles). Based on these results a partial structure of the degraded gum has been proposed, the additional evidence of which was deduced from periodate oxidation studies of the degraded gum.

Cytochemical Studies of Cell Wall Biosynthesis in Staphylococcus Aureus

1972 ◽  
Vol 30 ◽  
pp. 328-329
Author(s):  
Masaatsu Koike ◽  
Koichi Nakashima ◽  
Kyoko Iida
Keyword(s):  
Staphylococcus Aureus ◽  
Periodate Oxidation ◽  
Early Time ◽  
The Other ◽  
Penicillin G ◽  
Cell Wall Biosynthesis ◽  
Septal Wall ◽  
Peptidoglycan Biosynthesis ◽  
Gram Positive Bacteria ◽  
Cross Linkage

Penicillin exerts the activity to inhibit the peptide cross linkage between each polysaccharide backbone at the final stage of wall-peptidoglycan biosynthesis of bacteria. Morphologically, alterations of the septal wall and mesosome in gram-positive bacteria, which were occurred in early time after treatment with penicillin, have been observed. In this experiment, these alterations were cytochemically investigated by means of silver-methenamine staining after periodate oxidation, which is applied for detection of localization of wall mucopolysaccharide.Staphylococcus aureus strain 209P treated with 100 u/ml of penicillin G was divided into two aliquotes. One was fixed by Kellenberger-Ryter's OSO4 fixative at 30, 60 and 120 min after addition of the antibiotic, dehydrated through alcohol series, and embedded in Epon 812 (Specimen A). The other was fixed by 21 glutaraldehyde, dehydrated through glycolmethacrylate series and embedded in glycolmethacrylate mixture, according to Bernhard's method (Specimen B).

Solvation and redox properties of [Co(en)3]3+-[Co(en)3]2+ system

1980 ◽  
Vol 45 (2) ◽  
pp. 335-338 ◽  
Author(s):  
Adéla Kotočová ◽  
Ulrich Mayer
Keyword(s):  
Hydrogen Bond ◽  
Lewis Acid ◽  
Specific Interaction ◽  
Redox Properties ◽  
Solvation Effect ◽  
Interacting Particles ◽  
Acid Base ◽  
Polar Solvents ◽  
Oxidation Reduction ◽  
Solvent Molecules

The solvation effect of a number of nonaqueous polar solvents was studied on the oxidation-reduction properties of the [Co(en)3]3+-[Co(en)3]2+ system. Interactions of these ions with the solvent molecules are discussed in terms of their coordination, which is accompanied by a specific interaction of the Lewis acid-base type, namely formation of a hydrogen bond between the interacting particles. This is the main controlling factor of the redox properties of the studied system.

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