Paper details

Title:

The Use Of Dehydrogenases for Regenerating ß-Nicotinamide Adenine Coenzymes through Discontinuous and Continuous Processes

Author(s):

Andreotti, D.Z., Tomotani, E.J., Vitolo, M.

Document(s):

Abstract:

Efficiency is limited when any conversion is carried out with NAD or NADP-dependent dehydrogenase because both the oxidized and reduced forms of the coenzyme are interchanged inside the reactor. Such interchanging was evaluated through batch (conducted for 90min at 50 rpm and 30oC) and continuous (conducted for 30h at 100rpm and 30oC) processes, using a mixture of soluble glucose-6-phosphate dehydrogenase (G6PDH) and glutamate dehydrogenase (GLUDH). The batch and continuous approaches were, respectively, conducted in a 20 mL-vessel and in a 10 mL-cell-type membrane reactor (coupled with 500Da or 50kDa membrane). The reaction medium was constituted by 0.05 M TRIS-HCl buffer (pH 7.3), 5 mM MgCl2, 50 mM glucose-6­phosphate (G6P), G6PDH (2U), 0.2M 2-oxoglutarate (2-OXO), GLUDH (4U), 3.2 M (NH4)2SO4 and 500 µM NAD(P) (soluble or immobilized form). The membrane reactor was fed alternately every 2h with G6P or (2-OXO + (NH4)2SO4) solution. The NAD(P) was absorbed on DOWEX-1X4-100 in phosphate buffer (1x10-3 M; pH 8.0). Through the batch process, using soluble or insoluble NAD(P), about 90% and 80% of the initial amount of ammonium and G6P were consumed, respectively. Through the continuous process the highest G6P and ammonium consumption occurred with immobilized NAD, being around 53% and 36%, respectively.

Keywords:

batch reactor, biotechnology, enzymatic process

Topic:

Biological conversion - Fermentation, enzymatic processes

Subtopic:

Sources for biological conversion

Event:

18th European Biomass Conference and Exhibition

Session:

OA3.1

Pages:

1367 - 1370

ISBN-13:

978-88-89407-56-1

ISBN-10:

88-89407-56-5

Paper DOI:

10.5071/18thEUBCE2010-OA3.1

Price:

FREE