Polysaccharides, liquid crystalline phases

Other polysaccharides whose solutions yield liquid crystalline phases include the bacterial polysaccharide xylan and the extracellular fungal polysaccharide produced by schizophyllum commune... 

The interaction between polysaccharides and water was discussed. From NMR results, it was shown that water in the liquid crystalline phase is in a state ranging from a non-rigid solid to viscous liquid and that the motion of counter-ions is profoundly influenced by the molecular motion of water. 

NMR spectra of chiral molecules aligned in a chiral liquid crystalline solvent. A method for the visualization of enantiomers using natural abundant filtered single and double quantum selective refocusing experiments has been proposed and its application to small chiral molecules demonstrated. A lyotropic liquid crystalline phase of an aqueous solution of polysaccharide xanthan gum has been reported as a scalable weak alignment medium for enantiodiscrimination of water soluble chiral molecules. ... 

Since Robinson [1] discovered cholesteric liquid-crystal phases in concentrated a-helical polypeptide solutions, lyotropic liquid crystallinity has been reported for such polymers as aromatic polyamides, heterocyclic polymers, DNA, cellulose and its derivatives, and some helical polysaccharides. These polymers have a structural feature in common, which is elongated (or asymmetric) shape or chain stiffness characterized by a relatively large persistence length. The minimum persistence length required for lyotropic liquid crystallinity is several nanometers1. 

More than half a century ago, Bawden and Pirie [77] found that aqueous solutions of tobacco mosaic virus (TMV), a charged rodlike virus, formed a liquid crystal phase at as very low a concentration as 2%. To explain such remarkable liquid crystallinity was one of the central themes in the famous 1949 paper of Onsager [2], However, systematic experimental studies on the phase behavior in stiff polyelectrolyte solutions have begun only recently. At present, phase equilibrium data on aqueous solutions qualified for quantitative discussion are available for four stiff polyelectrolytes, TMV, DNA, xanthan (a double helical polysaccharide), and fd-virus. 

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