P. Gullapalli et al. / Tetrahedron: Asymmetry 18 (2007) 1995–2000
1999
37 °C in Erlenmeyer flasks (120 rpm) for 36 h. Batch
fermentations (10 L medium for biomass growth) were
performed in a 15 L bioreactor at 37 °C, with agitation rate
of 180 rpm and an airflow rate of 1.0/min.
kept in a desiccator for crystallization to give 1-deoxy-L-
fructose 4, (37 g, 74% overall yield) mp 72.2 °C,
20
½aꢁD ¼ þ85:5 (c 1.4, H2O) {lit.20 for the enantiomer
21
1-deoxy-D-fructose ½aꢁD ¼ ꢀ80:5 (c 1.0, H2O)}.
The effect of pH on 1-deoxy-L-fructose production was
studied using different buffers (50 mM sodium–phosphate
pH 6.0–8.0, 50 mM Tris–HCl pH 7.0–9.0 and 50 mM
glycine–NaOH pH 9.0–11.0). Transformation reactions
were carried out at 37 °C with shaking at 120 rpm in
30 mL L-shaped tubes, which contains the following reac-
tion mixture: 50 mg (1%) of substrate and 5.0 mL of a cell
suspension prepared in 50 mM of different buffers, which
had cell density of 20 (A600). Samples were taken at differ-
ent intervals and relative activity was determined by analy-
tical methods.
Acknowledgement
This work was supported in part by the Program for
Promotion of Basic Research Activities for Innovative Bio-
sciences (PROBRAIN).
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