Food Materials Research (Jan 2024)

Biocatalytic β-glucosylation/β-galactosylation of Rebaudioside C by glycosynthases

  • Ye-Yang Yu,
  • Si-Yu Zhang,
  • Jia-Hui Sun,
  • Yu-Yang Li,
  • Yao-Yao Zhang,
  • Ai-Min Lu,
  • Li Liu,
  • Josef Voglmeir

DOI
https://doi.org/10.48130/fmr-0023-0043
Journal volume & issue
Vol. 4, no. 1
pp. 1 – 6

Abstract

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Extracts of Stevia rebaudiana Bertoni plant leaves contain a mixture of diterpene glycosides which possess high sweetness and are used as non-caloric sweeteners in foods and beverages. One of the most abundant of these steviol glycosides is Rebaudioside C (Reb C), which bears one esterified β-D-glucose and one glycosidically linked α-L-rhamnosyl-(1→2)-[β-D-glucosyl-(1→4)]-D-glucose trisaccharide. In this work, we isolated Reb C from commercial Stevia extracts using an orthogonal normal-phase × reversed-phase purification strategy. We then demonstrated that Reb C could be used as a donor substrate for enzymatic trans glycosylation reactions using chemically synthesized 1-deoxy-1-fluoro-D-glucose and 1-deoxy-1-fluoro-D-galactose donors and two engineered glycosynthases derived from Agrobacterium and Streptomyces β-glycosidases. This chemoenzymatic glucosylation/galactosylation strategy may be of use to extend the current repertoire of steviol glycosides analogues for analysis or the sensory evaluation of these novel steviol glycosides.

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