An NMR spectroscopic characterisation of the enzyme-resistant residue from alpha-amylolysis of an amylose gel

The mobility and conformation of amylose in a gel form and its alpha-amylase resistant residue were probed through NMR relaxation experiments and high resolution C-13-CP/MAS NMR. The gel contained a double helical, rigid fraction and a more mobile amorphous fraction. Treatment of the gel with alpha-amylase resulted in the hydrolysis of part of the amorphous fraction, with further ordering of the remainder, to form a product, the amylose chains of which were essentially fully ordered and rigid as assessed by NMR.