HEMICELLULOSES OF WHEAT STRAW

1951 ◽  
Vol 29 (2) ◽  
pp. 109-122 ◽  
Author(s):  
G. A. Adams ◽  
A. E. Castagne
Keyword(s):  
Wheat Straw ◽  
Potassium Hydroxide ◽  
Uronic Acid ◽  
Degree Of Polymerization ◽  
Water Soluble ◽  
Hot Water ◽  
Acid Complex ◽  
Main Fraction ◽  
Hydrolysis Of ◽  
Soluble Fractions

Various hemicellulose fractions were extracted from wheat straw holocellulose (extractive and pectin free) by successive treatments with cold and hot water, 0.5%, 1.0%, and 2.0% potassium hydroxide and were recovered by precipitation with alcohol. Approximately 25% of the holocellulose material was removed, one half being in the hot water soluble fraction. The original holocellulose, the extracted residue, and the recovered fractions were analyzed for pentosan, uronic acid anhydride, acetyl, methoxyl, and ash content. In general, the more soluble fractions had a higher uronic acid and methoxyl content; the less soluble had a higher pentosan content and a more negative rotation [Formula: see text]. Intrinsic viscosity measurements indicated that all fractions had a degree of polymerization of 25–30. Hydrolysis of the main fraction yielded D-xylose, L-arabinose, D-glucose; in addition D-galactose was found in the water soluble fractions. Quantitative determinations of the sugars in the hydrolyzates showed that D-xylose predominated, with L-arabinose, D-glucose, and D-galactose (when present) in progressively smaller amounts. On hydrolysis all fractions yielded an acid-resistant uronic acid complex that contained D-xylose and a uronic acid tentatively identified as monomethoxyl galacturonic acid.

USE OF LIQUID AMMONIA IN THE FRACTIONATION OF WHEAT STRAW HOLOCELLULOSE

1950 ◽  
Vol 28b (12) ◽  
pp. 753-761 ◽  
Author(s):  
C. T. Bishop ◽  
G. A. Adams
Keyword(s):  
Wheat Straw ◽  
Potassium Hydroxide ◽  
Galacturonic Acid ◽  
Uronic Acid ◽  
Room Temperature ◽  
Liquid Ammonia ◽  
Cold Water ◽  
Acid Anhydride ◽  
Acid Complex ◽  
Molar Ratios

Wheat straw holocellulose, after soaking in liquid ammonia for 36 hr. at room temperature, was fractionated by successive extractions with cold water, 0.5% sodium carbonate, 0.5% potassium hydroxide, and 2.2% potassium hydroxide. Pretreatment with liquid ammonia increased the material soluble in cold water from 3% to 20.2%. Hemicellulose fractions were precipitated from the extracts by ethanol. A complete analytical balance was obtained by estimating ash, pentosan, uronic acid anhydride, acetyl, and methoxyl contents of the original holocellulose, of each of the fractions and of the residue. Analyses of the isolated fractions showed some systematic differences, with pentosan contents increasing and uronic acid anhydride decreasing progressively in the alkali soluble fractions. D-xylose, L-arabinose, D-glucose, D-galactose, and hexuronic acid in approximate molar ratios of 40:7:2:1:4 were found in the hemicellulose fractions. The presence of the sugars was confirmed by isolation of crystalline derivatives. A uronic acid complex, resistant to hydrolysis, was isolated and the components shown to be D-xylose and a monomethoxyl galacturonic acid.

ISOLATION OF THE ALDOBIURONIC ACID, 3-(XYLOPYRANOSYL) -α-D-GLUCURONOPYRANOSIDE, FROM WHEAT STRAW HOLOCELLULOSE AND SYNTHESIS OF ITS β-ISOMER

1953 ◽  
Vol 31 (2) ◽  
pp. 134-144 ◽  
Author(s):  
C. T. Bishop
Keyword(s):  
Wheat Straw ◽  
Potassium Hydroxide ◽  
Uronic Acid ◽  
Acid Anhydride ◽  
Dilute Acid ◽  
Polysaccharide Fraction ◽  
Hydrolysis Of

Extraction of wheat straw holocellulose with 4% potassium hydroxide removed a polysaccharide fraction containing D-xylose (77.2%), L-arabinose (6.9%), and uronic acid anhydride (7.9%). Hydrolysis of this polysaccharide with dilute acid produced a degraded polysaccharide which was precipitated by ethanol after removing free D-xylose from the hydrolyzate by fermentation with Hansenulasuaveolans. Prolonged hydrolysis of the degraded polysaccharide yielded an aldobiuronic acid which was shown to be 3-(xylopyranosyl)-α-D-glucuronopyranoside. The β-isomer of this compound was synthesized from D-glucurone and D-xylose and its structure was confirmed by degradative studies after methylation. The enzyme β-glucuronidase did not hydrolyze the α- or β-isomers of this aldobiuronic acid.

PURIFICATION AND COMPOSITION OF A POLYURONIDE HEMICELLULOSE ISOLATED FROM WHEAT STRAW

1952 ◽  
Vol 30 (7) ◽  
pp. 515-521 ◽  
Author(s):  
G. A. Adams ◽  
A. E. Castagne
Keyword(s):  
Petroleum Ether ◽  
Wheat Straw ◽  
Intrinsic Viscosity ◽  
Uronic Acid ◽  
Chloroform Solution ◽  
Degree Of Polymerization ◽  
Hot Water ◽  
Molar Ratio ◽  
Fractional Precipitation ◽  
Homogeneous Fraction

A homogeneous polyuronide hemicellulose has been prepared from a crude hemicellulose isolated from wheat straw holocellulose by hot water. The method of preparation consisted of fractional precipitation of the acetylated hemicellulose from chloroform solution by petroleum ether. Approximately 50% of the recovered fractions consisted of a polysaccharide made up of 28 moles of D-xylose, 5 moles of L-arabinose, and 3 moles of uronic acid and having an [Formula: see text] and a molar ratio, methoxyl: uronic anhydride, of approximately 1.0. Intrinsic viscosity measurements indicated a degree of polymerization of approximately 30. Separation of hexosans present in the original hemicellulose showed that they were not chemically combined with the main pentosan fraction. They were recovered admixed with short chain pentosan material containing a higher proportion of arabinose to xylose than the main homogeneous fraction.

scholarly journals Characteristics of the Water- and Alkali-Soluble Hemicelluloses Fractionated by Sequential Acidification and Graded-Ethanol from Sweet Maize Stems

Molecules ◽  
2019 ◽  
Vol 24 (1) ◽  
pp. 212 ◽  
Author(s):  
Xiaopeng Peng ◽  
Shuangxi Nie ◽  
Xiaoping Li ◽  
Xiong Huang ◽  
Quanzi Li
Keyword(s):  
Potassium Hydroxide ◽  
Ethanol Solution ◽  
Water Soluble ◽  
Hot Water ◽  
Fundamental Information ◽  
Composition And Structure ◽  
Structural Characterizations

Sweet maize stems were treated with hot water and potassium hydroxide to fractionate hemicellulosic polymers. The results showed that the water-soluble hemicelluloses were mainly composed of glucose (27.83%), xylose (27.32%), and galactose (16.81%). In comparison, alkali-soluble hemicelluloses fractionated by acidification and a graded ethanol solution (10%, 20%, 35%, 50%, 65%, and 80%) were mainly composed of xylose (69.73 to 88.62%) and arabinose (5.41 to 16.20%). More highly branched hemicelluloses tended to be precipitated in a higher concentration of ethanol solution, as revealed by the decreasing xylose to arabinose ratio from 16.43 to 4.21. Structural characterizations indicated that alkali-soluble hemicelluloses fractionated from sweet maize stems were mainly arabinoxylans. The results provided fundamental information on hemicelluloses composition and structure and their potential utilization in the fields of biofuels, biochemicals, and biomaterials.

THE EXTRACELLULAR POLYSACCHARIDE OF GELATINOUS STRAINS OF CHROMOBACTERIUM VIOLACEUM

1960 ◽  
Vol 6 (2) ◽  
pp. 153-163 ◽  
Author(s):  
William A. Corpe
Keyword(s):  
Uronic Acid ◽  
Extracellular Polysaccharide ◽  
Amino Sugar ◽  
Water Soluble ◽  
Chromobacterium Violaceum ◽  
Isolation And Identification ◽  
Isolation And Purification ◽  
Viscous Solution ◽  
Hydrolysis Of

A method for the isolation and purification of the voluminous extracellular polysaccharide of Chromobacterium violaceum is presented. The purified product was fibrous when wet but dried into a tough, pliable film which was completely water soluble, forming a highly viscous solution. Hydrolysis of the polysaccharide, isolation and identification of the components established the presence of glucose as the principal sugar. A uronic acid and an amino sugar not conclusively identified were also present. Glucose, uronic acid, and the amino sugar were found in an approximate 5:1:1 ratio.

THE WATER-SOLUBLE POLYSACCHARIDES OF DERMATOPHYTES: II. A GLUCAN FROM MICROSPORUM QUINCKEANUM

1963 ◽  
Vol 41 (10) ◽  
pp. 2621-2627 ◽  
Author(s):  
H. Alfes ◽  
C. T. Bishop ◽  
F. Blank
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Candida Albicans ◽  
Minimum Degree ◽  
Relative Number ◽  
Degree Of Polymerization ◽  
Water Soluble ◽  
Molar Ratio ◽  
Branch Points ◽  
Degree Of Branching ◽  
Hydrolysis Of

A levorotatory glucan with a minimum degree of polymerization of 36 has been isolated from the water-soluble polysaccharides of the dermatophyte Microsporum quinckeanum. Hydrolysis of the methylated glucan yielded the following O-methyl-D-glucoses: 2,3,4,6-tetra-(10.2 mole%); 2,3,4-tri- (57.7 mole%); 2,4,6-tri- (22.2 mole%); 2,4-di- (8.2 mole%); and 2-mono- (1.6 mole%). The glucan consumed 1.53 moles of periodate with production of 0.70 mole of formic acid per mole anhydroglucose. Reduction and hydrolysis of the periodate-oxidized glucan yielded glycerol, erythritol, and D-glucose in a molar ratio of 72.3:0.6:27.1. The results showed that the glucan consisted of β-D-glucopyranose units joined in straight chains by 1 → 6 (57%) and 1 → 3 (24%) linkages. Approximately 3 in every 37 glucose residues constitute branch points in the glucan with branches occurring at the C6 and C3 positions of the same glucose unit. The glucan bears some resemblance to the yeast glucans of Saccharomyces cerevisiae and Candida albicans but differs from them in the relative number of 1 → 6 and 1 → 3 linkages and in the degree of branching.

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.

CONSTITUTION OF AN ARABOGALACTAN FROM JACK PINE (PINUS BANKSIANA LAMB)

1957 ◽  
Vol 35 (9) ◽  
pp. 1010-1019 ◽  
Author(s):  
C. T. Bishop
Keyword(s):  
Methyl Ether ◽  
Pinus Banksiana ◽  
Jack Pine ◽  
Degree Of Polymerization ◽  
Average Degree ◽  
Water Soluble ◽  
Molar Ratio ◽  
Hydrolysis Of ◽  
Homogeneous Hydrolysis

A water soluble arabogalactan isolated from jack pine was shown to have a molar ratio of arabinose to galactose of 1:13, and a number average degree of polymerization of 53 ± 3. Fractionation data and electrophoresis indicated that the arabogalactan was homogeneous. Hydrolysis of the methyl ether of the polysaccharide yielded 2,3,5-tri-O-methyl-L-arabinose (4 moles); 2,3,4,6-tetra-O-methyl-D-galactose (12–13 moles); 2,3,4-tri-O-methyl-D-galactose (19 moles); 2,6-di-O-methyl-D-galactose (1 mole); and 2,4-di-O-methyl-D-galactose (14 moles). Some features of the structure of the arabogalactan are discussed on the basis of these results.

scholarly journals Enzymatic Hydrolysis of Water Extractable Polysaccharides from Leaves of Plantago major L.

Folia Medica ◽  
2017 ◽  
Vol 59 (2) ◽  
pp. 210-216 ◽  
Author(s):  
Paolina K. Lukova ◽  
Diana P. Karcheva-Bahchevanska ◽  
Veselin P. Bivolarski ◽  
Rumen D. Mladenov ◽  
Ilia N. Iliev ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Degree Of Polymerization ◽  
Hot Water ◽  
Cell Mediated Immunity ◽  
Plantago Major ◽  
Beneficial Effects ◽  
Hydrolysis Yield ◽  
Antiviral Activities ◽  
Hydrolysis Of ◽  
Water Extractable

AbstractBackground:Plantago majorL. leaves have been used for centuries by the traditional medicine in the treatment of infectious disorders of the respiratory, urinary and digestive tracts. Researchers have reported that hot water extracts ofPlantago majorpossess a broad-spectrum of anticancer, antioxidant and antiviral activities, as well as activities which modulate cell-mediated immunity. Their beneficial properties may be due to the significant content of polysaccharides. The polysaccharides that have been isolated from the leaves ofPlantago majorL. have different structures – pectic substances, galactans, arabinogalactans, glucomannans.Aim:The aim of this paper was to study the correlation between the structure of the water extractable polysaccharides isolated fromPlantago majorL. leaves and their enzymatic hydrolysis with different carbohydrate hydrolases.Materials and methods:The hydrolysis reactions were performed with the enzymes hemicellulase and mannanase. Spectrophotometric total reducing sugars assay was used to examine the hydrolysis yield. The monosaccharide and oligosaccharide compositions were determined using HPLC analysis.Results:The highest hydrolysis yield of the water extractable polysaccharides fromPlantago majorleaves was obtained by treatment with hemicellulase. The hydrolysis yield increased with the augmentation of the ratio of enzyme to polysaccharide. Galactose was the prevalent monosaccharide identified in the composition of the isolated polysaccharides. Oligosaccharides with different degree of polymerization were also detected.Conclusion:The enzymatic hydrolysis of water extractable polysaccharides fromPlantago majorleaves allows us to obtain different types of oligosaccharides with beneficial effects on both human health and industry.

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