A water-insoluble polysaccharide (PCS3-II) extracted from sclerotium of Poria cocos was identified as a linear (1→3)-β-D-glucan by 13C NMR and gas chromatography. Aqueous 0.5 M NaOH/0.2 M urea was a good solvent for PCS3-II and the dependence of intrinsic viscosity ([η]) on weight-average molecular weight (Mw) was established in the Mw range from 76800 to 514000 to be [η] = 0.0339 at 25 °C by using laser light scattering and viscometry. The chain conformation parameters of PCS3-II in the 0.5 M NaOH/0.2 M urea solution was 2.3 (±0.3) nm for persistence length (q), 580 g/mol/nm for molar mass per unit contour length (ML), 0.8 (±0.2) nm for the diameter of the chain (d) and 3.63 for limited characteristic ratio (C∞). The results revealed, for the first time, that PCS3-II existed as a flexible chain in 0.5 M NaOH/0.2 M urea aqueous solution.

conformation, Poria cocos, flexible chain, NaOH/urea aqueous solution

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
	bDGlcp	103.7	73.5	86.9	69.1	77.0	61.6


1H NMR data:
missing...

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

*O[C@@H]1[C@@H](O)[C@H](*)O[C@H](CO)[C@H]1O

162.141 g/mol (C₆H₁₀R₂O₅, R = next and previous repeats, not counted in mol weight)