The Hemicelluloses of Western Red Cedar: The Constitution of a Glucomannan<sup>1</sup>

Hamilton, J. K.; Partlow, E. V.

doi:10.1021/ja01551a029

Cited by 12 publications

(9 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…I he mannose-to-glucose ratios of 2.7 and 3.8 found here are similar to those reported for other soft\\~oocl glucomannans, such as (2.5) red cedar (22), (3) \vestern hemlock (1, a), ("7) loblolly pine (13), (3.1 -3.7) Scots pine (8, 31), (3.3-4) Noi-\\ray spruce (27,32), (2.3) Sitlca spruce (12), ancl (3) white spruce (24, 3).…”

Section: Rsupporting

confidence: 89%

“…Glucoruannans from recl cedar (22), ~vestei-11 11emlock (21), ancl S i t l a spruce (12) are stated t o be essentially linear, 1111iereas similar glucomar~-nans from Scots pine (8) and Nor~vaj-spruce (27) are rcportecl to be branched. The number-average degree of polj-merization founcl here (93) is ~vithin the same range as the values observed for glucomannans from (130) western hcmlocl; (21), (70-113) Scots pine (32), (68-100) Nor\\ra)r spruce (27), and (107) white spruce (24).…”

Section: Rmentioning

confidence: 99%

“…The mannotriose has been obtai~iecl crj-stalline from loblolly pine (15) and \\rliite spruce \voocl (24) and was PI-obabll. also present in glucomannaii liydrolyzates from \\-ester11 l l e l~l l~~l i ('LI), I-ecl cedar (22), a~~d spruce sulphite pulp (23). The mannotetraose has been isolated previousl\-on1~-from vegetable ivorl- (25) and from white spi-ice 11-oocl (24).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Constitution of a Glucomannan From the Wood of Eastern White Pine (Pinus Strobus L.)

Gyaw¹,

Timell²

1960

Can. J. Chem.

View full text Add to dashboard Cite

Glucomannans have been isolated from the wood of eastern \\lliite pine ( P i n u s ~t i . 0 6~1~ L.) by two different methods, the ratios of Inannose to glucose being 3.S:l and 2.7:l,respectively. In recent years it has beco~ne evident t h a t the mannose residues in the mood of gymnosperms largely originate from glucomannan (1) or galactoglucomani~a~~ (2) heteropol!-mers. Glucomannans are the rnai~l hemicelluloses of soft\voocls and have lately been isolatecl from several species. . I previous investigation (3) dealt xvith a n arabino-4-0-m e t l~y l g l~~c~~r o n o x y l a n from the wood of white pine (Pi?zus strobzts L.). T h e present p.'per is concerned with the isolation ancl properties of a glucomannan from the same species.RESULTS A S D DISCCSSIOX \Yliite pine \vood (11.7% mannose resiclues) was delignified u i t h acid chlorite (4) to gil-e a holocellulose \vhich still contained a t least 3% lignin. Estraction with aqueous sodium hydroxide containing borate ( 5 ) gave a mixture of hemicelluloses ~vhich was not ainenable to resolution by complesing with copper (G). Better results were obtai~led bl.7 the barium hydroside method ( 7 ) , but the precipitated glucomannan still contained 6.4' ;; galactose residues n-hich could not be removed by further treatments.X glucolnannan from Scots pine (Pinrls syluestris L.) mas recentl>-also found to retain galactose residues which could be removecl only after complete elirniilation of residual lignin (8). T h e present crude glucomannan had a n ultraviolet spectrurll indicative of the occurrence of lignin, and the latter was accordingly eliminated by treatment with chlorine and ethanola~nine (9). T h e hemicellulose obtained on copper complesi~lg of the delignified material contained less than 2y0 galactose residues. Evidently, the lignin left in the crude hemicellulose acted as a binding agent between the main glucomannan component and other polysaccharides containing galactose residues. \TThether the association mas of a chemical or physical nature could not be decided on the basis of the present evidence.T h e purified gluco~nannan, [aID -32', contained glucose and mannose residues in a ratio of 1:3.8 and amounted to 10.G% by n-eight of the ~vood. Osmotic pressure measure-1-tIanz~script received M a y 20, 1.960.

show abstract

Section: Rsupporting

confidence: 89%

Section: Rmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Constitution of a Glucomannan From the Wood of Eastern White Pine (Pinus Strobus L.)

Gyaw¹,

Timell²

1960

Can. J. Chem.

View full text Add to dashboard Cite

show abstract

“…Other western redcedar wood constit uen t s i nc I ud e p-d o I a b r i n (Gard ner and Barton 1958a, Gardner 1963, nezukone (Hirose and Nakatsuka 1967), cumic acid (Barton and MacDonald 1971), unnamed soluble and insoluble phenols Gardner 1954, Krueger 1968), and various hemicelluloses (Lewis 1950, Hamilton andPartlow 1958). Western redcedar hemicel I u loses are si mi lar to those of other conifers, except that the xylan contains a lower percentage of L-arabinose (Dutton and Funnel1 1973).…”

Section: Forest Products Laboratory 1955)mentioning

confidence: 99%

Western redcedara literature review.

Minore¹

1983

View full text Add to dashboard Cite

show abstract

“…The polysaccharide (2g) was kept with 72% sulphuric acid (13,14), (25') overnight and made up to a normal solution with respect to sulphuric acid by cautious dilution (to avoid reprecipitation) with water. The solution was heated for 10 hours in boiling water bath, when the hydrolysis, which was followed iodometrically (15), was found to be complete.…”

Section: Hydrolysis and Identification Of D-galactose And D-il!fannosementioning

confidence: 99%

A Water-Soluble Galactomannan From Coconut (Cocos Nucifera): Part I. Methylation Studies

Rao¹,

Choudhury²,

Bagchi³

1961

Can. J. Chem.

View full text Add to dashboard Cite

A water-soluble polysaccharide isolated from the kernel of coconut (Cocos nucifera) had [ a ]~ -85O and contained D-galactoSe (1 mole) and D-mannoSe ( 2 moles). Methylation and hydrolysis yielded 2,3,4,6-tetra-0-methyl-D-mannose (0.51 mole); 2,3,4,6-tetra-0-methyl-Dgalactose (0.5 mole) ; 2,3,6-tri-0-methyl-D-mannose (5.52 moles) ; 2,3,6-tri-0-methyl-D-galactose (1.51 moles) ; and a di-0-methyl-D-galactose (1 mole). These data agree with those of periodate oxidation. T h e structural significance of these results is discussed.T h e kernel of coconut (Cocos nz~cifera), a tree which is generally found in coastal regions of India and south-east Asia is a popular food. T h e kernel is soft when the fruit is young and becomes hard when old. Although much work has been done on the oil (1) extracted from the kernel, copra (2), the liquid (3) within the shell, and other parts of the fruit such as the coir (4) etc., the polysaccharide in the kernel does not appear t o have been investigated. This paper deals with the studies on the polysaccharide precipitated from the aqueous extract of the kernel with ethanol. Hydrolysis of the polysaccharide [~r ]~~~ -85' (in 4% sodium hydroxide solution) gave D-galactose and D-mannose in the proportion 1 : 2 as revealed by chromatographic analysis (5). Traces of arabinose were also formed. Purification of the polysaccharide via the copper con~plex (6) removed the arabinose-containing impurities a s well as traces of uronides, and hydrolysis showed t h a t the galactose: mannose ratio was the same as before.The galactomanilail was methylated first by methyl sulphate and sodium hydroxide and then by Purdie's method. The resulting methylated galactomannan, which showed no hydroxyl band a t 3500-3600 cm-I in I.R. spectrum, was light yellow in color and had [aID25 +25' in chloroform. After methanolysis of the methylated polysaccharide and hydrolysis of the mkthyl glycosides the mixture of methylated sugars was resolved on a cellulose colun~n (7) using butanone-water azeotrope (8) a s eluant.From the results of the column chroinatography the mixture was found to consist of 2,3,4,6-tetra-0-methyl-D-mannose (0.51 mole), 2,3,4,6-tetra-0-methyl-D-galactose (0.5 mole), 2,3,6-tri-0-methyl-D-mannose (5.52 moles), 2,3,6-tri-0-methyl-D-galactose (1.51 moles), and a di-0-methyl-galactose (1 mole). The proportions of the above sugars were determined in a separate experilllent using alltaline hypoiodite method (9). I t will be evident froin the above results that the proportion of tetra-:tri-:di-0-methyl sugars is as 1:7:1 indicating that the polysaccharide possesses a highly branched structure and t h a t the average repeating unit consists of about 9 hexose residues.The two tetra-0-methyl sugars mere separated on filter papers. The 2,3,4,6-tetra-0-methyl-D-mannose obtained a s sirup after elution and evaporation, having [aID3O +3' in water, was characterized a s N-phenyl-2,3,4,6-tetra-O-n1ethyl-~-mannosylamiie, m.p. and mixed 1n.

show abstract

The Hemicelluloses of Western Red Cedar: The Constitution of a Glucomannan¹

Cited by 12 publications

References 14 publications

Constitution of a Glucomannan From the Wood of Eastern White Pine (Pinus Strobus L.)

Constitution of a Glucomannan From the Wood of Eastern White Pine (Pinus Strobus L.)

Western redcedara literature review.

A Water-Soluble Galactomannan From Coconut (Cocos Nucifera): Part I. Methylation Studies

Contact Info

Product

Resources

About

The Hemicelluloses of Western Red Cedar: The Constitution of a Glucomannan1

Cited by 12 publications

References 14 publications

Constitution of a Glucomannan From the Wood of Eastern White Pine (Pinus Strobus L.)

Constitution of a Glucomannan From the Wood of Eastern White Pine (Pinus Strobus L.)

Western redcedar&#151;a literature review.

A Water-Soluble Galactomannan From Coconut (Cocos Nucifera): Part I. Methylation Studies

Contact Info

Product

Resources

About

The Hemicelluloses of Western Red Cedar: The Constitution of a Glucomannan¹

Western redcedara literature review.