Production of β-Fructofuranosidase by Arthrobacter sp. and Its Application in the Modification of Stevioside and Rebaudioside A 

Zhong-Wei Xu¹, Yu-Qiang Li¹, Yong-Hua Wang¹*, Bo Yang² and Zheng-Xiang Ning<sup>1

1</sup>College of Light Industry and Food Sciences, South China University of Technology, CN-510640, Guangzhou, PR China
²School of Bioscience and Bioengineering, South China University of Technology, CN-510006, Guangzhou, PR China

Article history:
Received April 4, 2008
Accepted November 28, 2008

Key words:
β-fructofuranosidase, purification, stevioside and rebaudioside A, structure modification

Summary:
Arthrobacter sp. 10137 has been used to produce β-fructofuranosidase (FFase). Sucrose and corn steep powder in an optimized ratio of 10:1 were the best carbon and nitrogen sources for enzyme production in a shake flask. The maximum FFase activity was 26.69 U/mL after 22.5 h in batch culture, and the crude FFase, obtained by ultrafiltration and (NH₄)₂SO₄ fractionation, was purified about 7-fold as measured by specific activity from the crude culture filtrate. The FFase was specific for introduction of a fructose molecule at the C₁₉ position on both the stevioside and rebaudioside A, with high transfructosylating activity of 65 % after 15 h of incubation.

*Corresponding author:           yonghw@scut.edu.cn
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