Glucomannans isolation

OE097 Tejero Mateo, M. P., A. Gil Serrano, and ]. PemandeZ Blanos. Polysaccharides in olives. VII. Study a galacto-glucomannan isolated from olive pulp of the variety Gordal. Ann Quim Ser C 1986 82(2) 158-161. OEllO... 

Constit. of the glucomannan isol. from the cells of the fungus Ceratocystis brutmea. [a]g> +72 (H2O). 

K. Bauerovd, D. Mihalova, K. Drabikovd, V. Jancinova, J. Kucharska, E. Paulovicova, R. Nosal, S. Ponist, Effects of glucomannan isolated from Candida utilis on adjuvant arthritis in Lewis rats, Curr. Topics Nutraceutical Res., 10 (1), 13-30,2012. 

V. Hdjkovd, A. Svobodovd, D. Krejcovd, M. Ciz, V. Velebny, A. Lojek, J. El-Benna, L. Kubala, Soluble glucomannan isolated from Candida utilis primes blood phagocytes, Carbohydr. Res., 344, 2036-2041, 2009. 

The fact that glucomannan is obtained from GDP-D-mannose as substrate suggests that the particulate enzyme contains an epimerase which converts GDP-D-mannose to GDP-D-glucose. However, such an epimerase has not been observed. In this connection cellulose isolated from wood contains a considerable amount of D-mannose. 

Similarly-constituted glucomannans have been isolated from various species of iris seeds107 and lily bulbs,108 the polysaccharides containing D-glucose and D-mannose residues in the proportions 1 1.1 and 1 1.9, respectively. The iris-seed glucomannans also contain a small proportion of D-galactopyranose end-groups.107... 

It was formerly believed that coniferous woods contain a mannan. However, before the polysaccharide containing the mannose residues was isolated in a state of purity, Leech d and Anthis> were able to show that it was a glucomannan, by the isolation of disaccharides containing both glucose and mannose from a hydrolysate of polysaccharide material enriched in the mannose-containing material. This observation was later confirmed by the isolation of pure glucomannans from these woods. - ... 

Smith and Srivastava showed that lies mannan, from the tubers of a species of Amorphophalhis, is a true glucomannan (of the same type as wood glucomannans) by isolating 4-0-/3-D-mannopyranosyl-D-glucose and 4-0-/3-D-glucopyranosyl-D-mannose from a partial hydrolyzate. 

Polysaccharides have been isolated which contain both D-glucose and D-mannose, for example, the glucomannan of Amorphophallus konjacJ From this Konjac mannan ([a] o —42.8°) has been isolated a disaccharide composed of D-glucose and D-mannose units. The polysaccharide from the corms of Amorphophallus oncophyllus is a fibrous substance which contains 49 % of anhydroglucose, 41 % of anhydromannose, and 4 % of uronic anhydride, and yields 2 % of pentosans. This substance is an excellent beater additive when used in paper manufacture. 

Jones and coworkers, in studies on mannose-containing polysaccharides, have isolated, from seeds of Iris ochroleuca and Iris sibirica, heterogeneous polysaccharides yielding on hydrolysis D-glucose and D-mannose in approximately equal amounts, as well as D-galactose (m. 3 %). These workers consider the possibility that the polysaccharides are mixtures of glucomannan with galactomannan, but, because of the similarity (in composition) between the two iris polysaccharides, tend to the view that they are... 

Structures of Several Glucomanno-oligosaccharides Isolated from Enzymic Hydrolyzates of Glucomannans... 

Unlike their softwood relatives, hardwood glucomannans do not contain any galactose residues and are thus true glucomannans. Their diheteropolymer character is indicated (but not proved) by the fact that they give only one peak on free-boundary (Tiselius) electrophoresis - and retain a constant composition on repeated fractionation. More-direct evidence is furnished by the isolation and identification of 4-0- 8-D-glucopyranosyl-D-mannopyranose and 4-0- 3-D-mannopyranosyl-D-glucopyranose on partial hydrolysis. ... 

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