Tamarind polysaccharide structure

The rheological behavior of storage XGs was characterized by steady and dynamic shear rheometry [104,266]. Tamarind seed XG [266] showed a marked dependence of zero-shear viscosity on concentration in the semi-dilute region, which was similar to that of other stiff neutral polysaccharides, and ascribed to hyper-entanglements. In a later paper [292], the flow properties of XGs from different plant species, namely, suspension-cultured tobacco cells, apple pomace, and tamarind seed, were compared. The three XGs differed in composition and structural features (as mentioned in the former section) and... 

The analysis of monosaccharide mixtures as the permethylated derivatives was proposed early in the application of gas-liquid chromatography to carbohydrates, but the method has now been superseded by more convenient procedures.230,231 There are, however, situations in which this method is useful, such as during a structural study of a polysaccharide by the methylation technique. The mixture of partially methylated monosaccharides obtained by methanolysis may then be fully methylated, and the proportions of the various monosaccharides determined. This approach has been used, for example, in studies on a galactomannan392 and on tamarind-kernel polysaccharide.393 Such an analysis also constitutes a useful check to ensure that no significant change in the composition of the polysaccharide occurred during methylation. 

Gidley, M.J., Lillford, P.J., Rowlands, D.W., Lang, P., Dentini, M. and Crescenzi, V. (1991) Structure and solution properties of tamarind-seed polysaccharide. Carbohydrate Research 214, 299-314. 

Srivastava, H.C. and Singh, P.P. (1967) Structure of the polysaccharide from tamarind kernel. Carbohydrate Research 4(4), 326-342. 

An examination of another sample of the tamarind-kernel polysaccharide has given markedly different results, and it must be concluded that this preparation represents a distinct polysaccharide.151 The structural features outlined in the partial formula 87 are clearly present, as shown in a similar series of experiments. The composition of this polysaccharide is, however, clearly different from that reported... 

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