A METHOD FOR THE IDENTIFICATION OF THE MONO-O-METHYLGLUCOSES

1953 ◽  
Vol 31 (9) ◽  
pp. 814-820 ◽  
Author(s):  
R. U. Lemieux ◽  
H. F. Bauer
Keyword(s):  
Paper Chromatography ◽  
Sodium Borohydride ◽  
Alkaline Hydrolysis ◽  
Periodate Oxidation ◽  
Methyl Cellulose ◽  
Water Soluble ◽  
The Other ◽  
Potential Value ◽  
Hydrolysis Of

Periodate oxidation of any one mono-O-methylglucopyranose and alkaline hydrolysis of the product yields a substance which can be positively distinguished by paper chromatography from the products formed under the same conditions from the other mono-O-methylglucopyranoses. Thus, the components of a mixture of the mono-O-methylglucopyranoses can be readily identified. The method appears useful for the identification of di-O-methylglucoses. Reduction with sodium borohydride prior to periodate oxidation renders the method useful for the identification of tri-O-methylglucoses. The potential value of the method, which can be used on a microscale, is illustrated by an application to the characterization of the O-methylglucoses derived from a water-soluble O-methyl-cellulose

CHARACTERIZATION OF THREE HEMICELLULOSES FROM THE WOOD OF AMABILIS FIR (ABIES AMABILIS)

1963 ◽  
Vol 41 (6) ◽  
pp. 1381-1388 ◽  
Author(s):  
E. C. A. Schwarz ◽  
T. E. Timell
Keyword(s):  
Periodate Oxidation ◽  
Specific Rotation ◽  
Water Soluble ◽  
Partial Hydrolysis ◽  
Abies Amabilis ◽  
A Value ◽  
Linear Framework ◽  
Molecular Rotations ◽  
Hydrolysis Of

An arabino-4-O-methylglucuronoxylan (10:14:76), a water-soluble galactoglucomannan (1:1:3), and an alkali-soluble galactoglucomannan (0.1:1:3) have been isolated in yields of 7, 4, and 8% from the wood of amabilis fir (Abies amabilis). The structure of the polysaccharides was established by methylation and periodate oxidation techniques. The xylan ([Formula: see text]) contained side chains of (1 → 2)-linked 4-O-methyl-α-D-glucuronic acid and (1 → 3)-linked α-L-arabinofuranose residues, both attached directly to a linear framework of (1 → 4)-linked β-D-xylose residues. The galactoglucomannans ([Formula: see text] 76 and 95) contained (1 → 6)-linked α-D-galactopyranosyl residues attached directly to a backbone of (1 → 4)-linked β-D-mannose and β-D-glucose residues. Partial hydrolysis of the two hexosans yielded 10 and 13 oligosaccharides, respectively, containing (1 → 4)-β-D-mannose, (1 → 4)-β-D-glucose, and (1 → 6)-α-D-galactopyranose residues. The molecular rotations of a series of mannooligosaccharides corresponded to a value of −54° for the specific rotation of an infinitely long mannan. It is concluded that the main hemicelluloses in amabilis fir wood are the same as those occurring in the wood of gymnosperms from other genera. The same three hemicelluloses are also present in the bark of this species.

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.

REACTIONS OF OXODELCOSINE AND INTERRELATION OF DELCOSINE AND DELSOLINE

1960 ◽  
Vol 38 (12) ◽  
pp. 2433-2440 ◽  
Author(s):  
Vinko Skarić ◽  
Léo Marion
Keyword(s):  
Sodium Borohydride ◽  
Membered Ring ◽  
Lead Tetraacetate ◽  
The Other ◽  
Supporting Evidence ◽  
Close Relationship ◽  
Suggested Structure ◽  
Hydrolysis Of

The oxidation of diacetyldelcosine produces a lactam which, after hydrolysis of the acetyl groups, can be oxidized further to a diketo-lactam in which one of the keto groups is in a five- and the other in a six-membered ring. This result leads to an alteration of the previously suggested structure of delcosine. The new structure suggests a close relationship between delcosine and delsoline which is confirmed by the methylation of the former. The reaction is selective and gives rise to a monomethyldelcosine identical in every way with delsoline. Reduction of the diketo-lactam (didehydro-oxodelcosine) with sodium borohydride gives oxodelcosine. Dehydro-oxodelcosine is also described, and its oxidation with lead tetraacetate as well as that of oxodelcosine lead to the formation of keto-products which lend supporting evidence for the structure assigned to delcosine.

CONSTITUTION OF A WATER SOLUBLE HEMICELLULOSE FROM AMERICAN BEECHWOOD (FAGUS GRANDIFOLIA)

1957 ◽  
Vol 35 (6) ◽  
pp. 556-564 ◽  
Author(s):  
G. A. Adams
Keyword(s):  
Average Molecular Weight ◽  
Periodate Oxidation ◽  
Reducing Power ◽  
Fagus Grandifolia ◽  
Water Soluble ◽  
Hot Water ◽  
Molar Ratio ◽  
Weight Average Molecular Weight ◽  
Homogeneous Fraction ◽  
Hydrolysis Of

Extraction of beechwood chlorite holocellulose with hot water yielded a hemicellulose in 13.4% yield (based on original extractive-free wood) containing D-xylose 72%, D-galactose 11.0%, and uronic acid 13.2%. Purification of the crude hemicellulose by complexing with Fehling's solution yielded a chemically homogeneous fraction containing D-xylose 83% and 4-O-methyl-D-glucuronic acid 15.5%. Hydrolysis of the fully methylated hemicellulose yielded 2,3,4-tri-O-methyl-D-xylose, 2,3-di-O-methyl-D-xylose, 3-O-methyl-D-xylose, and 3-O-methyl-2-O-(2,3,4-tri-O-methyl-D-glucopyranosyluronic acid)-D-xylose in a molar ratio of 2:35:3:5. On the basis of the methylation data, periodate oxidation, reducing power determinations, and weight average molecular weight values a possible structure for the hemicellulose is proposed.

scholarly journals Metabolic studies on retinoic acid in the rat

1971 ◽  
Vol 122 (1) ◽  
pp. 1-4 ◽  
Author(s):  
P. R. Sundaresan ◽  
H. N. Bhagavan
Keyword(s):  
Retinoic Acid ◽  
Alkaline Hydrolysis ◽  
Water Soluble ◽  
Major Metabolite ◽  
Metabolic Studies ◽  
Hydrolysis Of ◽  
Soluble Fractions

The nature of metabolites in the urine arising from differentially labelled retinoic acid was investigated after injection of physiological doses into retinol-deficient rats. Distribution of radioactivity after partition of urine into ether-soluble, acidic and water-soluble fractions revealed that there were at least six metabolites in urine. Of these, the major metabolite(s) was one lacking both C-14 and C-15 of retinoic acid. Enzymic or alkaline hydrolysis of acidic and water-soluble fractions did not release any retinoic acid, thus indicating that retinoyl β-glucuronide was not present in urine in significant amounts.

Identification and structural characterization of four novel degradation products and a process impurity of isavuconazonium sulfate for injection formulation bulk by LC-ESI-QTOF-MS/MS

2019 ◽  
Vol 26 (2) ◽  
pp. 144-152
Author(s):  
Venkata Rama Prabhakara Sastry Regella ◽  
Venkatesan Chidambaram Subramanian ◽  
Sarveswara Sastry Bhetanabhotla
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Structural Characterization ◽  
Alkaline Hydrolysis ◽  
Degradation Products ◽  
Water Soluble ◽  
Tandem Mass ◽  
Light Conditions

Isavuconazonium sulfate is a highly water-soluble pro-drug of active triazole isavuconazole. The degradation profile of isavuconazonium sulfate for injection formulation bulk under acid hydrolysis, alkaline hydrolysis, oxidation, heat, and light conditions was studied using LC-PDA/MS technique. Four degradation products (DP1 to DP4) and one process impurity (PI1) were identified in isavuconazonium sulfate formulation bulk and characterized the identified impurities by liquid chromatography-electron spray ionization-quadruple-time of flight tandem mass spectrometry. Isavuconazole (DP1) was found to be one of the major degradation products of isavuconazonium sulfate.

scholarly journals Production and Characterization of Highly Thermostableβ-Glucosidase during the Biodegradation of Methyl Cellulose byFusarium oxysporum

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Folasade M. Olajuyigbe ◽  
Chidinma M. Nlekerem ◽  
Olusola A. Ogunyewo
Keyword(s):  
Residual Activity ◽  
Methyl Cellulose ◽  
Industrial Applications ◽  
Biofuel Production ◽  
Fermentable Sugars ◽  
Original Activity ◽  
Fermentation Period ◽  
Ph Range ◽  
Hydrolysis Of

Production ofβ-glucosidase fromFusarium oxysporumwas investigated during degradation of some cellulosic substrates (Avicel,α-cellulose, carboxymethyl cellulose (CMC), and methylcellulose). Optimized production ofβ-glucosidase using the cellulosic substrate that supported highest yield of enzyme was examined over 192 h fermentation period and varied pH of 3.0–11.0. Theβ-glucosidase produced was characterized for its suitability for industrial application. Methyl cellulose supported the highest yield ofβ-glucosidase (177.5 U/mg) at pH 6.0 and 30°C at 96 h of fermentation with liberation of 2.121 μmol/mL glucose. The crude enzyme had optimum activity at pH 5.0 and 70°C. The enzyme was stable over broad pH range of 4.0–7.0 with relative residual activity above 60% after 180 min of incubation.β-glucosidase demonstrated high thermostability with 83% of its original activity retained at 70°C after 180 min of incubation. The activity ofβ-glucosidase was enhanced by Mn2+and Fe2+with relative activities of 167.67% and 205.56%, respectively, at 5 mM and 360% and 315%, respectively, at 10 mM. The properties shown byβ-glucosidase suggest suitability of the enzyme for industrial applications in the improvement of hydrolysis of cellulosic compounds into fermentable sugars that can be used in energy generation and biofuel production.

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.

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