Semi-Continuous Flow Biocatalysis with Affinity Co-Immobilized Ketoreductase and Glucose Dehydrogenase

The co-immobilization of ketoreductase (KRED) and glucose dehydrogenase (GDH) on highly cross-linked agarose (sepharose) was studied. Immobilization of these two enzymes was performed via affinity interaction between His-tagged enzymes (six histidine residues on the N-terminus of the protein) and agarose matrix charged with nickel (Ni2+ ions). Immobilized enzymes were applied in a semicontinuous flow reactor to convert the model substrate; α-hydroxy ketone. A series of biotransformation reactions with a substrate conversion of >95% were performed. Immobilization reduced the requirement for cofactor (NADP+) and allowed the use of higher substrate concentration in comparison with free enzymes. The immobilized system was also tested on bulky ketones and a significant enhancement in comparison with free enzymes was achieved.

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Modeling Trienzyme Biosensor at Internal Diffusion Limitation

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2004.9.2.15162 ◽

2004 ◽

Vol 9 (2) ◽

pp. 139-144 ◽

Cited By ~ 1

Author(s):

J. Kulys

Keyword(s):

Immobilized Enzymes ◽

Internal Diffusion ◽

Significant Response ◽

Diffusion Limitation ◽

Enzyme Reactions ◽

Substrate Conversion ◽

Apparent Stability ◽

Biosensor Response

A model of biosensor containing three immobilized enzymes utilizing consecutive substrate conversion in the chain was developed. The modeling was performed at an internal diffusion limitation and a steadystate condition. The calculations showed that significant response of biosensors was produced if diffusion modules were larger than 1 for all enzyme reactions. Due to diffusion limitation the apparent stability of biosensor response increased many times in comparison to stability of the most labile enzyme of the chain.

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Renewable Energy from Agricultural Waste

Revista de Chimie ◽

10.37358/rc.18.6.6325 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1363-1366 ◽

Cited By ~ 1

Author(s):

Stefania Daniela Bran ◽

Petre Chipurici ◽

Mariana Bran ◽

Alexandru Vlaicu

Keyword(s):

Saccharomyces Cerevisiae ◽

Gas Chromatography ◽

Continuous Flow ◽

Laboratory Experiments ◽

Fermentation Process ◽

Flow Reactor ◽

Agricultural Waste ◽

Continuous Flow Reactor ◽

Natural Support ◽

Co2 Flow

This paper has aimed at evaluating the concentration of bioethanol obtained using sunflower stem as natural support, molasses as carbon source and Saccharomyces cerevisiae yeast in a continuous flow reactor. The natural support was tested to investigate the immobilization/growth of S. cerevisiae yeast. The concentration of bioethanol produced by fermentation was analyzed by gas chromatography using two methods: aqueous solutions and extraction in organic phase. The CO2 flow obtained during the fermentation process was considered to estimate when the yeast was deactivated. The laboratory experiments have highlighted that the use of plant-based wastes to bioconversion in ethanol could be a non-pollutant and sustainable alternative.

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