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Updated: Jul 26, 2026

Molecular Entanglement and Electrospinnability of Biopolymers
Published on: September 3, 2014
Effect of substitution at C-6 on the susceptibility of pullulan to pullulanases. Enzymatic degradation of modified
D H Ball1, B J Wiley, E T Reese
1U.S. Army Natick Research, Development and Engineering Center, MA 01760-5020.
Abstract:
Pullulan, with all of the primary hydroxyl groups modified, is an excellent substrate for defining the effect of degree of substitution on biodegradability because of the uniform distribution of substituents on the polysaccharide. 6-Chloro-6-deoxypullulan and 3,6-anhydropullulan are highly resistant to hydrolysis by the four different types of pullulanase. 6-Azido-6-deoxypullulan is resistant to three types but susceptible to hydrolysis by the fourth, isopullulanase. Neopullulanase is strongly inhibited by 6-chloro-6-deoxypullulan and 6-azido-6-deoxypullulan, the other pullulanases much less so.
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