@article{SHEN2025, 
author = {Jidong SHEN and Baoping XU and Lianggang HUANG and Zhiqiang LIU and Yuguo ZHENG},
title = {Study on Immobilization of Hyperthermophilic D-Allulose 3-Epimerase and Properties of Immobilized Enzyme},
year = {2025},
journal = {Journal of Food Science and Technology},
volume = {43},
number = {2},
pages = {42-50},
keywords = {enzyme immobilization, rare sugar, D-allulose 3-epimerase, D-allulose, high temperature catalysis},
url = {https://www.sciopen.com/article/10.12301/spxb202400021},
doi = {10.12301/spxb202400021},
abstract = {D-allulose, a promising low-calorie natural sweetener and a key member of the rare sugar family, exhibits physiological benefits in mitigating multiple diseases. As the C-3 epimer of D-fructose, D-allulose was synthesized through the catalytic action of D-allulose 3-epimerase (DAE). However, industrial-scale sugar epimerization required high-temperature conditions (greater than 65 ℃), and existed DAEs could not meet this requirement. To address this bottleneck, a hyperthermophilic DAE (TI-DAE) was immobilized using diatomite as a solid core, polyethyleneimine (PEI) as a protective shell, and glutaraldehyde (GA) as a cross-linking agent, resulting in the formation of a core-shell-structured immobilized enzyme (TI-DAE@Diatomite-PEI-GA), and its structure and performance were characterized. The result revealed that immobilized enzyme TI-DAE@Diatomite-PEI-GA exhibited better pH and thermal stability than the free enzyme TI-DAE. The half-life of TI-DAE@Diatomite-PEI-GA was greater than 24 h, 11 times higher than free enzyme under 90 ℃. Furthermore, TI-DAE@Diatomite-PEI-GA retained over 70% relative activity after 20 batches of converting 500 g/L D-fructose into D-allulose. The results proved that the enzyme immobilization technology based on diatomite covalent cross-linking could greatly improve the thermostability of DAE, reduce the cost of industrial production of D-allulose, break through a technical bottleneck of current industrial production, and lay a foundation for promoting the industrialization of enzymatic synthesis of D-allulose.}
}