Enantioselective Steroid Reduction via Two-Phase Biocatalysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current industrial processes for the enantioselective reduction and oxidation of steroid compounds are limited by low substrate concentrations, poor solubility in aqueous media, and inefficient cofactor regeneration, leading to low turnover numbers and economic inefficiencies.
Innovation Solution
The process involves operating at higher steroid compound concentrations (≥50 g/l) with continuous regeneration of cofactors NAD or NADP using secondary alcohols or cycloalkanols, and employing additional oxidoreductases to enhance cofactor regeneration, facilitating enantioselective reductions and oxidations in an aqueous organic two-phase system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If substrate concentration is increased to improve productivity, then turnover number increases, but solubility in aqueous medium deteriorates
Solution Approach 1:
The patent introduces an organic solvent as an intermediary substance that mediates between the aqueous enzyme environment and the steroid substrate. The organic solvent increases substrate solubility in the aqueous phase, enabling higher substrate concentrations (≥50 g/l) without precipitation, thus resolving the contradiction between productivity and solubility
Solution Approach 2:
The patent creates a composite reaction system combining aqueous phase (containing enzyme and cofactor) with organic phase (containing substrate). This two-phase composite system allows the substrate to dissolve in the organic phase while the enzyme acts in the aqueous phase, enabling high substrate concentration and high turnover number simultaneously
2Productivity
If cofactor regeneration is improved to enhance efficiency, then turnover number increases, but process complexity increases
Solution Approach 1:
The patent implements self-service cofactor regeneration by adding a regeneration system that automatically replenishes NADH/NADPH during the reaction. The organic solvent serves dual purposes: as a solubility enhancer and as a cofactor regeneration medium, eliminating the need for complex external regeneration equipment and achieving high turnover numbers through self-sustaining cofactor cycling
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 approach significantly increases turnover numbers, enabling more economical and efficient enantioselective reactions, with at least 50% conversion of oxosteroid or hydroxysteroid compounds within 2 to 96 hours, exceeding previous concentration ranges and achieving TTN ≥103.
Implementation Method 1
the oxosteroid compound is reduced with a hydroxysteroid dehydrogenase in the presence of a cofactor NADH or NADPH
Implementation Method 2
the oxidized cofactor NAD or NADP formed by the hydroxysteroid dehydrogenase is regenerated continuously by oxidation
Implementation Method 3
an additional oxidoreductase/alcohol dehydrogenase is used for the oxidation of the secondary alcohol or of the cycloalkanol
Implementation Method 4
the oxidized cofactor NAD or NADP formed by the hydroxysteroid dehydrogenase is regenerated continuously by oxidation of a secondary alcohol
Implementation Method 5
facilitating enantioselective reductions and oxidations in an aqueous organic two-phase system
Data Source
AI summary
A process for the enantioselective reduction of compounds having a steroid structure (ABCD) including one or several heteroatoms, one or several double bonds and/or aromatic components in the ring structure and having at least one oxo group at positions 3, 7, 11, 12 or 17 in the steroid ring system or in the a-position of any carbon moiety of the steroid structure:comprising providing the oxosteroid compound in the reaction at a concentration of ≧50 g/L, a reduced cofactor NADH or NADPH, a hydroxysteroid dehydrogenase and a secondary alcohol or cycloalknaol to effect the enantioselective reduction.