A molecular description of the gelation mechanism of curdlan.
The gelation of aqueous suspensions of the polysaccharide curdlan has been studied by dynamic rheological measurements, differential scanning calorimetry, and low-resolution time-domain 1H-NMR. Gel formation from several samples, each originating from a curdlan fraction of differing molecular weight, has been observed in order to further clarify the nature of observed phenomena by monitoring their dependence on degree of polymerisation. The results from the complementary techniques described here, in addition to those in existing literature, both for curdlan and for other ss-(1,3) glucans, have been used to build up a consistent framework for the interpretation of results. Broadly, this involves the plasticisation and dissolution of dried material on heating, the time-dependent annealing of native (as biosynthesised) structures, and the trapping of imperfectly formed pseudo-equilibrium states on re-cooling, in concert with the creation of microfibrils and network formation.
Zhang
Hongbin
H
College of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Nishinari
Katsuyoshi
K
Williams
Martin A K
MA
Foster
Tim J
TJ
Norton
Ian T
IT
D002152:Calorimetry, Differential Scanning; D004548:Elasticity; D005782:Gels; D005936:Glucans / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008970:Molecular Weight; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D012212:Rheology; D014783:Viscosity; D014867:Water; D047071:beta-Glucans
D005782:Gels; D005936:Glucans; D011135:Polysaccharides, Bacterial; D047071:beta-Glucans; D014867:Water; C038459:curdlan; C033363:beta-1,3-glucan