Production of d-tagatose at high temperatures using immobilized Escherichia coli cells expressing l-arabinose isomerase from Thermotoga neapolitana
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Escherichia coli cells expressing l-arabinose isomerase from Thermotoga neapolitana (TNAI) were immobilized in calcium alginate beads. The resulting cell reactor (2.4 U, t 1/2 = 43 days at 70°C) in a continuous recycling mode at 70°C produced 49 and 38 g d-tagatose/l from 180 and 90 g d-galactose/l, respectively, within 12 h.
Keywordsl-Arabinose isomerase Esherichia coli Immobilization d-Tagatose Thermotoga neapolitana
This work was supported by grant 2001-2-0109 from the Korea Science and Engineering Foundation and grant AIC-08-02 from the Ministry of Commerce, Industry and Energy, Korea.
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