Glucose Isomerisation via Sorbitol Intermediate and Cofactor Regeneration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for isomerizing glucose to fructose face limitations such as low substrate concentration, low overall yields, and the need for laborious separation processes, particularly in achieving high fructose enrichment.
Innovation Solution
A method involving a one-pot reaction that reduces glucose to sorbitol and subsequently oxidizes it to fructose, with cofactors NAD+/NADH and NADP+/NADPH being regenerated, allowing for higher substrate concentrations and simultaneous cofactor regeneration reactions within the same batch, using specific enzymatic redox reactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional isomerase methods are used for glucose isomerisation, then the process is simple and well-established, but the maximum fructose conversion is limited to approximately 42%
Solution Approach 1:
The isomerisation process is divided into two separate enzymatic steps: first reducing glucose to sorbitol using xylose reductase, then oxidizing sorbitol to fructose using sorbitol dehydrogenase. This segmentation allows each reaction to proceed to completion without being limited by equilibrium constraints, achieving over 99% fructose enrichment.
Solution Approach 2:
Sorbitol is introduced as an intermediate compound in the reaction pathway. By converting glucose to sorbitol first, and then sorbitol to fructose, the process bypasses the equilibrium limitations of direct isomerisation, enabling complete conversion and high fructose yield.
2Manufacturing precision
If chromatographic methods are used for fructose enrichment, then high purity fructose can be obtained, but the process becomes laborious and complex
Solution Approach 1:
The enzymatic reaction system self-regulates to achieve complete conversion of glucose to fructose through the two-step redox process. The cofactor regeneration systems automatically maintain the necessary redox balance, eliminating the need for external separation and purification operations.
Solution Approach 2:
The process changes the reaction parameters by using two different enzymatic pathways with specific cofactor requirements (NAD+ for reduction, NADP+ for oxidation). By optimizing these biochemical parameters and implementing in-situ cofactor regeneration, the system achieves high purity fructose without complex separation equipment.
3Manufacturing precision
If individual redox reactions are used for fructose production, then each reaction can be optimized separately, but multiple separate reactions increase operational costs and time
Solution Approach 1:
The reduction and oxidation reactions are merged into a single one-pot reaction system. Both enzymatic reactions occur simultaneously in the same reaction vessel with continuous cofactor regeneration, eliminating the need for separate reaction steps, intermediate isolation, and multiple purification operations.
Solution Approach 2:
The cofactor regeneration systems operate continuously throughout the reaction process, maintaining the redox balance without interruption. The NAD+ and NADP+ cofactors are regenerated in-situ, allowing both enzymatic reactions to proceed continuously without stopping for cofactor replenishment.
4Productivity
If low substrate concentrations are used in one-pot systems, then the reaction can proceed efficiently, but the overall productivity and yield are reduced
Solution Approach 1:
The process optimizes substrate concentration parameters by implementing continuous cofactor regeneration systems that maintain efficient reaction kinetics even at high substrate concentrations. The dual cofactor system (NAD+ and NADP+) allows both reactions to proceed simultaneously without inhibition, enabling high productivity with high substrate loading.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method achieves significant fructose enrichment, with fructose concentrations reaching up to 99.9% and reduced operational costs and time, overcoming the limitations of existing technologies by enabling efficient and high-yield fructose production without cumbersome separation methods.
Implementation Method 1
the reduction of D-glucose to D-sorbitol
Implementation Method 2
xylose reductase may be used to reduce D-glucose to D-sorbitol
Implementation Method 3
the oxidation of D-sorbitol to D-fructose
Implementation Method 4
sorbitol dehydrogenase
Implementation Method 5
acetaldehyde is reduced to ethanol
Implementation Method 6
alcohol dehydrogenase
Implementation Method 7
pyruvate is reduced to lactate
Implementation Method 8
lactate dehydrogenase
Data Source
AI summary
Disclosed is a method for the isomerization of glucose by reduction to sorbitol and subsequent oxidation to fructose, in which the redox cofactors NAD+/NADH and NADP+/NADPH are regenerated in a one-pot-reaction, wherein one of the two redox cofactors is obtained in the reduced form thereof and the other redox cofactor in the oxidized form thereof as a result of at least two additional enzymatically catalyzed redox reactions (product forming reactions) taking place in the same reaction batch, wherein a) in the regeneration reaction, which transfers the reduced cofactor back to its originally oxidized form, oxygen or a compound of the general formula R1C(O)COOH is reduced, and b) in the regeneration reaction, which transfers the oxidized cofactor back to its originally reduced form, a compound of the general formula R2CH(OH)R3 is oxidized, wherein R1, R2 and R3 have different meanings in the compounds, characterized in that a mixture of glucose and fructose is used as a starting material. Furthermore, the use of fructose thus produced in a method for producing furan derivatives is disclosed.