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Updated: Feb 2, 2026

Determination of Glucan Chain Length Distribution of Glycogen Using the Fluorophore-Assisted Carbohydrate Electrophoresis FACE Method
Published on: March 31, 2022
Sucrose-based biosynthetic process for chain-length-defined α-glucan and functional sweetener by Bifidobacterium
Seong-Won Choi1, Jung-A Lee1, Sang-Ho Yoo1
1Department of Food Science & Biotechnology, and Carbohydrate Bioproduct Research Center, Sejong University, Seoul 05006, Republic of Korea.
Abstract:
A unique thermostable amylosucrase from Bifidobacterium thermophilum was produced as a recombinant protein with the half-life of 577 h at 50 °C. By adding 1.0 M fructose, turanose yield was improved from 22.7% to 43.3% with 1.0 M sucrose, and from 23.7% to 39.4% with 1.5 M sucrose. Sucrose consumption rate was greatest at 55 °C, but the lowest amount of turanose was produced. Thus, turanose yield from sucrose biomass was inversely proportional to reaction temperature and was highly dependent on [fructose]. Meanwhile, insoluble α-glucan yield was clearly reduced as [fructose] increased. With 1.0 M fructose + 1.0 M sucrose, glucan byproduct yield significantly decreased from 29.4% to 1.1%. Molecular weights of linear glucans were almost identical among various [sucrose]s and were homogenous with very low polydispersity. This unique dual reaction patterns of amylosucrase enzyme would be very useful for massive productions of two different biomaterials simply by changing sucrose biomass concentration.
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