Can I read Enzymatic Production and Complete Nuclear Magnetic Resonance Assignment of the Sugar Lactulose on EtoBox?

Enzymatic Production and Complete Nuclear Magnetic Resonance Assignment of the Sugar Lactulose by Jürgen Mayer; Jürgen Conrad; Iris Klaiber; Sabine Lutz-Wahl; Uwe Beifuss; Lutz Fischer is a Agricultural and Biological Sciences article available to read on EtoBox.

What is Enzymatic Production and Complete Nuclear Magnetic Resonance Assignment of the Sugar Lactulose about?

The enzymatic transgalactosylation from lactose to fructose leading to the prebiotic disaccharide lactulose was investigated using the β-galactosidase from Aspergillus oryzae and the hyperthermostable β-glycosidase from Pyrococcus furiosus (CelB). The conditions for highest lactulose yields relative to the initial lactose concentration were established on a 1 mL scale. Dependent on the initial molar ratio of lactose to fructose, more or fewer oligosaccharides other than lactulose were generated. Bioconversions on a 30 mL scale in a stirred glass reactor were performed, and lactulose yields of 46 mmol/L (44% relative to lactose) for CelB and 30 mmol/L (30% relative to lactose) for A. oryzae β-galactosidase were achieved. Only <5% of other oligosaccharides were detectable. The corresponding productivities were 24 and 16 mmol/L/h, respectively. The molecular structure of lactulose was investigated in detail and confirmed after purification of the reaction solution by LC-MS and 1D and 2D NMR. Lactulose (4-O-β-D-galactopyranosyl-D-fructose) was unambiguously proved to be the major transglycosylation disaccharide.

Who reads Enzymatic Production and Complete Nuclear Magnetic Resonance Assignment of the Sugar Lactulose?

Author

Jürgen Mayer; Jürgen Conrad; Iris Klaiber; Sabine Lutz-Wahl; Uwe Beifuss; Lutz Fischer

Publisher

American Chemical Society (ACS)

Published

2004

Language

EN

Field

Agricultural and Biological Sciences (Life Sciences)