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High-yield continuous production of nicotinic acid via nitrile hydratase–amidase cascade reactions using cascade CSMRs

Paper ID Volume ID Publish Year Pages File Format Full-Text
17498 42673 2011 6 PDF Available
Title
High-yield continuous production of nicotinic acid via nitrile hydratase–amidase cascade reactions using cascade CSMRs
Abstract

High yields of nicotinic acid from 3-cyanopyridine bioconversion were obtained by exploiting the in situ nitrile hydratase–amidase enzymatic cascade system of Microbacterium imperiale CBS 498-74.Experiments were carried out in continuously stirred tank UF-membrane bioreactors (CSMRs) arranged in series. This reactor configuration enables both enzymes, involved in the cascade reaction, to work with optimized kinetics, without any purification, exploiting their differing temperature dependences. To this end, the first CSMR, optimized for the properties of the NHase, was operated (i) at low temperature (5 °C), limiting inactivation of the more fragile enzyme, nitrile hydratase, (ii) with a high residence time (24 h) to overcome reaction rate limitation. The second CSMR, optimized for the properties of the AMase, was operated (i) at a higher temperature (50 °C), (ii) with a lower residence time (6 h), and (iii) with a lower substrate (3-cyanopyridine) concentration to control excess substrate inhibition. The appropriate choice of operational conditions enabled total conversion of 3-cyanpyridine (up to 200 mM) into nicotinic acid to be achieved at steady-state and for long periods. Higher substrate concentrations required two CSMRs optimized for the properties of the NHase arranged in series to drive the first reaction to completion.

Keywords
Nitrile hydratase–amidase cascade system; 3-Cyanopyridine bioconversion; Nicotinic acid; Series arranged continuous stirred membrane reactor
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High-yield continuous production of nicotinic acid via nitrile hydratase–amidase cascade reactions using cascade CSMRs
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Publisher
Database: Elsevier - ScienceDirect
Journal: Enzyme and Microbial Technology - Volume 48, Issues 4–5, 7 April 2011, Pages 345–350
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us