Applied Biochemistry and Biotechnology

, Volume 166, Issue 4, pp 961–973

Production of d-tagatose, a Functional Sweetener, Utilizing Alginate Immobilized Lactobacillus fermentum CGMCC2921 Cells

Authors

  • Zheng Xu
    • State Key Laboratory of Materials-Oriented Chemical Engineering
    • College of Food Science and Light IndustryNanjing University of Technology
  • Sha Li
    • State Key Laboratory of Materials-Oriented Chemical Engineering
    • College of Food Science and Light IndustryNanjing University of Technology
  • Fenggen Fu
    • State Key Laboratory of Materials-Oriented Chemical Engineering
    • College of Food Science and Light IndustryNanjing University of Technology
  • Guixiang Li
    • State Key Laboratory of Materials-Oriented Chemical Engineering
    • College of Food Science and Light IndustryNanjing University of Technology
  • Xiaohai Feng
    • State Key Laboratory of Materials-Oriented Chemical Engineering
    • College of Food Science and Light IndustryNanjing University of Technology
    • State Key Laboratory of Materials-Oriented Chemical Engineering
    • College of Food Science and Light IndustryNanjing University of Technology
  • Pingkai Ouyang
    • College of Biotechnology and Pharmaceutical EngineeringNanjing University of Technology
Article

DOI: 10.1007/s12010-011-9484-8

Cite this article as:
Xu, Z., Li, S., Fu, F. et al. Appl Biochem Biotechnol (2012) 166: 961. doi:10.1007/s12010-011-9484-8

Abstract

d-tagatose is a ketohexose that can be used as a novel functional sweetener in foods, beverages, and dietary supplements. This study was aimed at developing a high-yielding d-tagatose production process using alginate immobilized Lactobacillus fermentum CGMCC2921 cells. For the isomerization from d-galactose into d-tagatose, the immobilized cells showed optimum temperature and pH at 65 °C and 6.5, respectively. The alginate beads exhibited a good stability after glutaraldehyde treatment and retained 90% of the enzyme activity after eight cycles (192 h at 65 °C) of batch conversion. The addition of borate with a molar ratio of 1.0 to d-galactose led to a significant enhancement in the d-tagatose yield. Using commercial β-galactosidase and immobilized L. fermentum cells, d-tagatose was successfully obtained from lactose after a two-step biotransformation. The relatively high conversion rate and productivity from d-galactose to d-tagatose of 60% and 11.1 g l−1 h−1 were achieved in a packed-bed bioreactor. Moreover, lactobacilli have been approved as generally recognized as safe organisms, which makes this L. fermentum strain an attracting substitute for recombinant Escherichia coli cells among d-tagatose production progresses.

Keywords

d-Tagatose Lactobacillus fermentum Immobilized cells Packed-bed bioreactor l-arabinose isomerase

Copyright information

© Springer Science+Business Media, LLC 2011