Conformation of (2-->1)-beta-D-fructan in aqueous solution.
The conformation and dilute solution properties of (2-->1)-beta-D-fructan in aqueous solution were studied by gel permeation chromatography, low-angle laser light-scattering photometry, viscometry, small-angle X-ray scattering and electron microscopy. Fractions covering a broad range of weight-average molecular weights (Mw) from 1.49 x 10(4) to 5.29 x 10(6) were obtained from a native sample by ultrasonic degradation and fractional precipitation. For Mw < 4 x 10(4), the intrinsic viscosity [eta] varies with Mw0.71, indicating that the fructan chain behaves as a random coil expanded by an excluded-volume effect in this molecular weight region. For Mw > 10(5), [eta] exhibits an unusually weak dependence on Mw and finally becomes almost independent of molecular weight. This behaviour is interpreted in terms of a globular conformation of the high-molecular-weight fructan molecules. Small-angle X-ray-scattering measurements and electron microscopic observations support this interpretation of the values of [eta] observed.
Kitamura
S
S
Department of Agricultural Chemistry, Kyoto Prefectural University, Japan.
Hirano
T
T
Takeo
K
K
Mimura
M
M
Kajiwara
K
K
Stokke
B T
BT
Harada
T
T
D001230:Aspergillus / Q000378:metabolism; D002236:Carbohydrate Conformation; D002850:Chromatography, Gel; D005630:Fructans / Q000737:chemistry*; D008854:Microscopy, Electron; D008970:Molecular Weight; D012542:Scattering, Radiation; D012996:Solutions; D014783:Viscosity; D014867:Water; D014961:X-Ray Diffraction
C093302:(2-1)-fructan; D005630:Fructans; D012996:Solutions; D014867:Water