Access the full text.
Sign up today, get DeepDyve free for 14 days.
R. Wichmann, C. Wandrey, A. Bückmann, M. Kula (1981)
Continuous enzymatic transformation in an enzyme membrane reactor with simultaneous NAD(H) regenerationBiotechnology and Bioengineering, 23
Masahisa Ikemi, N. Koizumi, Y. Ishimatsu (1990)
Sorbitol production in charged membrane bioreactor with coenzyme regeneration system: I. Selective retainment of NADP(H) in a continuous reactionBiotechnology and Bioengineering, 36
E. King, C. Altman (1956)
A Schematic Method of Deriving the Rate Laws for Enzyme-Catalyzed ReactionsThe Journal of Physical Chemistry, 60
(1982)
Coenzyme Regeneration (Springer-Verlag, Berlin
Y. Yamazaki, H. Maeda (1982)
The Co-immobilization of NAD and Dehydrogenases and Its Application to Bioreactors for Synthesis and AnalysisAgricultural and biological chemistry, 46
K. Hayakawa, I. Urabe, H. Okada (1985)
Operational stability of a continuous enzyme reactor containing poly(ethylene glycol)-bound NAD and thermostable dehydrogenasesJournal of Fermentation Technology, 63
10.1002/bit.260360208.abs A theoretical model was constructed in order to study charged membrane bioreactors (CMBRs). In this model, it was postulated that a native nicotinamide coenzyme NADP(H) can be partially retained by a charged membrane in continuous operation. A multienzyme system composed of NADPH‐dependent aldose reductase (AR) and glucose dehydrogenase (GDH) was used for the production of sorbitol and gluconic acid from glucose and for the conjugated enzymatic regeneration of NADP(H). Both enzymes were studied with respect to their reaction kinetics. AR was determined to obey the Theorell–Chance mechanism. GDH reaction was approximated by the initial velocity equation of the sequential Bi–Bi mechanism since the reverse reaction could be neglected. Significant inhibitions of both enzymes by sorbitol, gluconic acid, and glucose were observed, and the mode of inhibition was estimated to modify the velocity equations. The differential equation system for each component was derived and numerically analyzed according to the model. The theoretical model elucidated several features of the CMBR. (1) When compared at the same productivity, higher retainment was found to bring about a higher coenzyme turnover number, indicating that the feed coenzyme concentration can be reduced. (2) Under constant conversion, a contradictory relationship between turnover number and residence time arises if the feed concentration of a coenzyme varies. The theoretical model predicts that there is a practically optimal concentration for using NADP(H) efficiently. This concentration was consistent with that yielding the estimated minimum total cost. (3) In this system, excess‐GDH‐to‐AR activity was required because of differences in their kinetic constants. The amount of regeneration enzyme required can be reduced by the accumulation of excels NADPH due to coenzyme retainment. (4) Comparison with an ideal repeated batch reaction revealed that the continuously operated CMBR was vastly superior with respect to productivity as well as operation ability.
Biotechnology and Bioengineering – Wiley
Published: Jun 20, 1990
Read and print from thousands of top scholarly journals.
Already have an account? Log in
Bookmark this article. You can see your Bookmarks on your DeepDyve Library.
To save an article, log in first, or sign up for a DeepDyve account if you don’t already have one.
Copy and paste the desired citation format or use the link below to download a file formatted for EndNote
Access the full text.
Sign up today, get DeepDyve free for 14 days.
All DeepDyve websites use cookies to improve your online experience. They were placed on your computer when you launched this website. You can change your cookie settings through your browser.