[Study on molecular chain morphology and chain parameters of konjac glucomannan].
OBJECTIVE
To study the molecular chain morphology and chain parameters of konjac glucomannan (KGM).


METHODS
Solution behavior was studied by using light scattering(LS), gel permeation chromatograph (GPC) and method of viscosity. The molecular morphology was observed directly by atom force microscope (AFM) and transmission electron microscope (TEM).


RESULTS
The average molecular weight (Mw), root-mean-square ratio of gyration(<S2>1/2), second Viral coefficients (A2) and multi-disperse coefficients (Mw/Mn) are 1.04 x 10(6), 105.0 +/- 0.9 nm, (-1.59 +/- 0.28) x 10(-3) mol.mL.g-2 and (1.020 +/- 0.003) respectively; Mark-Houwink equation was established as [eta] = 5.96 x 10(-2) Mw0.73, the molecular chain parameters were as follows: ML = 982.82 nm-1, q = 27.93 nm, d = 0.74 nm, h = 0.26 nm, L = 1,054.11 nm.


CONCLUSIONS
Both the result showed by direct observation and the deduction drawn by solution behavior confirmed that the KGM molecular is stentering semi-flexible linear chain without branch.
Natural Product Chemistry Research Laboratory, Food Science Department of Huazhong Agricultural University, Wuhan 430070, China.
Bin
B
Li
Bi-jun
BJ
Xie
D031056:Amorphophallus / Q000737:chemistry; D002850:Chromatography, Gel / Q000379:methods; D008027:Light; D008351:Mannans / Q000737:chemistry* / Q000302:isolation & purification; D018625:Microscopy, Atomic Force; D008970:Molecular Weight; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D012542:Scattering, Radiation; D014783:Viscosity
D008351:Mannans; D011134:Polysaccharides; C022901:(1-6)-alpha-glucomannan