Of laminarin

Laminarin is the reserve carbohydrate of the sublitoral brown algae, especially Laminaria. There are two types of laminarin as regards solubility, the normal or water-insoluble laminarin (from L. cloustoni) and a soluble type (from L. digitata). These two kinds of laminarin differ only in solubility and are otherwise indistinguishable in composition and structure. They will not be further differentiated in this description. 

On acetylation of laminarin followed by simultaneous deacetylation and methylation, Barry112 obtained methylated laminarin, among the hydrolytic products of which he identified 2,4,6-trimethyl-D-glucose... 

Barry114 isolated a disaccharide, laminaribiose, on the partial hydrolysis of laminarin by enzymes (digestive juice of the snail Helix pomatia or H. aspersa) or by acid (seven hours with N oxalic acid on the water-bath). He showed that this disaccharide consisted solely of D-glucose and considered it to be 3-j3-D-glucopyranosyl-D-glucopyranose (XXIX). 

Acknowledgements We thank M.J.E.C. van der Maarel and H. Helmers for the analysis of the viscosity of laminarin. L. Seuront is acknowledged for stimulating comments on an earlier version of the manuscript. 

Elykova, L.A. Reunov, A.V. Mozhaeva, K.A. Protection of Tobacco Plants Against Tobacco Mosaic Virus by b-l,3 l,6-Glucan Antivir Obtained by Enzymatic Transformation of Laminarin. Dokl. Akad. NauL 1994, 336, 710-711. CAN 122 5729. 

Laminarin, a less viscous phycolloid amply foimd in Laminaria and Saccharina, has shown its capability to promote higher production of butyric acid through bacterial fermentation (Deville et al., 2004). Butyrates are important energy-yielding metabolites for the colonial epithelial cells and account for about 70% of the energy requirement of the colon (Reilly et al., 2008). Prebiotic effects of laminarin studied in animal models reported that 1% dietary supplementation resulted in an increase in... 

Isol. from partial acid hydrolysate of Laminarin, L-20 and Pachyman. [ajo -5.9 (H2O). 

Some a-anomer present in the crystalline state. Acid hydrolysis product of Laminarin, L-20, pachyman and yeast P-glucan. Isol. from the partial hydrolysate of sclerotia of Sclerotiorum sclerotinia. Dihydrate (MeOH). 

Polysilicic acid reacts with proteins and mucopolysaccharides but not cellulose acetate, according to Holt and Went (180). At about pH 6 it reacts with a monolayer film of laminarin, a linear polysaccharide of 20 units of beta-D-glucopyranase linked through C and C, atoms. Probably hydrogen bonding with ether oxygens is involved. 

The combination of polysilicic acid at pH 6 with a film of laminarin (poly-1,3 glucopyranose) making it rigid was reported by Holt and Went (247). One might suppose that this polyhydroxy polyether would form hydrogen bonds with silicic acid below pH 6, but since the combination occurred at pH 6, it is possible that some spontaneous chelation dr estenflcation had occurred. 

The following study of laminarin polysaccharides illustrates the potential of MALDI-MS for rapidly and sensitively defining the degree of polymerization (d.p.) of carbohydrate polymers and for revealing structural modifications which result in altered molecular weight. 

In the field of reducing trimers P-l,3-linked oligomers of D-glucose, which are constituent parts of laminarin, have been prepared by use of 2-0-benzoyl-4,6-O-benzylidene-3-O-chloroacetyl-P-D-glucopyranosyl chloride. The trimer and oligomers up to octamer were described. ... 

Alban, S., Kraus, J., and Franz, G. (1992) Synthesis of laminarin sulfates with anticoagulant activity. Arzneim.-Forsch. Drwg Res., 42 (11), 1005-1008. 

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