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.

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.

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.

Dilute Acid Hydrolysis of Wheat Straw Oligosaccharides

2008 ◽  
Vol 153 (1-3) ◽  
pp. 116-126 ◽  
Author(s):  
Luís C. Duarte ◽  
Talita Silva-Fernandes ◽  
Florbela Carvalheiro ◽  
Francisco M. Gírio
Keyword(s):  
Acid Hydrolysis ◽  
Wheat Straw ◽  
Dilute Acid ◽  
Dilute Acid Hydrolysis ◽  
Hydrolysis Of

Effect of Dilute-Acid-Hydrolysis Treatments on the Utilization of Wheat Straw by Rumen Bacteria and Free Enzymes

1992 ◽  
Vol 1992 ◽  
pp. 212-212
Author(s):  
F.B. de Castro ◽  
P.M. Hotten ◽  
E.R. Ørskov
Keyword(s):  
Cell Wall ◽  
Acid Hydrolysis ◽  
Wheat Straw ◽  
Effect Of Temperature ◽  
Rumen Bacteria ◽  
Dilute Acid ◽  
Cell Wall Polysaccharides ◽  
Dilute Acid Hydrolysis ◽  
Physical Treatment ◽  
Hydrolysis Of

Extensive hydrolysis of cell wall polysaccharides by rumen bacteria or free enzymes has been reported when lignocellulosic materials had been treated with steam and pressure (Dekker & Wallis, 1983; Castro & Machado, 1989). This has mainly been explained by complete hydrolysis of hemicellulose, lignin depolymerization and redistribution within the cell wall and increasing accessible pore volume by swelling of the cell walls. Physical treatment based on use of steam and pressure alone (auto-hydrolysis) is always associated with the release of toxic levels of furfural and phenolic monomers. These chemicals are able to inhibit the activity of rumen microorganisms, yeasts and free enzymes. To overcome this effect, dilute-acid-hydrolysis at low temperatures and pressures has been proposed (Grohmann et al., 1985). The aim of this study was to evaluate the effect of temperature, sulphuric acid concentration and reaction time on the utilization of treated wheat straw by dilute-acid-hydrolysis, either by rumen bacteria and free enzymes.

Improved enzymatic hydrolysis of wheat straw by combined use of gamma ray and dilute acid for bioethanol production

2014 ◽  
Vol 94 ◽  
pp. 231-235 ◽  
Author(s):  
Sung Hyun Hong ◽  
Jae Taek Lee ◽  
Sungbeom Lee ◽  
Seung Gon Wi ◽  
Eun Ju Cho ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wheat Straw ◽  
Gamma Ray ◽  
Bioethanol Production ◽  
Dilute Acid ◽  
Combined Use ◽  
Hydrolysis Of
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