4 results
Now showing1 - 4 of 4
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Bioreactive separation technology: a retrospective and perspective(Elsevier, 2026-03-28); ; ; ; Bluemke, WilfriedBiocatalysis, using enzymes or whole cells, offers high selectivity under mild conditions, but its broader application is often hindered by slow kinetics, equilibrium limitations, product inhibition and the processing of dilute streams in the presence of enzymes and cells. Bioreactive separation, defined as the simultaneous process of biocatalysis and separation, provides a powerful concept to overcome these barriers and therefore offers the potential of superiority over conventional processes. The current retro- and perspective paper, which is the result of an interdisciplinary workshop with academic and industry experts from the areas of biotechnology, fluid separations and process systems engineering, provides a focussed review, paired with a distinct novel definition of bioreactive separations that links to multifunctional reactors in chemical engineering and in situ product removal in biocatalysis. By establishing a common framework, this definition connects different research areas and enables systematic development. The current status of bioreactive separation processes is evaluated using SWOT analyses to identify key potentials and challenges. Based on this, a vision for 2040 is outlined, highlighting the need for advances in integration strategies, biocatalyst design, modelling and simulation, and applied research. Overall, a coordinated progress in these areas can significantly enhance the scalability and sustainability of bioprocessing.Publicationtype: Review Article48 31 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Electrochemical H₂O₂ - stat mode as reaction concept to improve the process performance of an unspecific peroxygenase(Elsevier, 2023-12-25); ; ; ; The electroenzymatic hydroxylation of 4-ethylbenzoic acid catalyzed by the recombinant unspecific peroxygenase from the fungus Agrocybe aegerita (rAaeUPO) was performed in a gas diffusion electrode (GDE)-based system. Enzyme stability and productivity are significantly affected by the way the co-substrate hydrogen peroxide (H2O2) is supplied. In this study, two in-situ electrogeneration modes of H2O2 were established and compared. Experiments under galvanostatic conditions (constant productivity of H2O2) were conducted at current densities spanning from 0.8 mA cm−2 to 6.4 mA cm−2. For comparison, experiments under H2O2-stat mode (constant H2O2 concentration) were performed. Here, four H2O2 concentrations between 0.06 mM and 0.28 mM were tested. A maximum H2O2 productivity of 5.5 µM min−1 cm−2 and productivity of 10.5 g L−1 d−1 were achieved under the galvanostatic condition at 6.4 mA cm−2. Meanwhile, the highest total turnover number (TTN) of 710,000 mol mol−1 and turnover frequency (TOF) of 87.5 s−1 were obtained under the H2O2-stat mode at concentration limits of 0.15 mM and 0.28 mM, respectively. The most favorable outcome in terms of maximum achievable TTN, TOF and productivity was found under the H2O2-stat mode at concentration limit of 0.2 mM. Here, a TTN of 655,000 mol mol−1, a TOF of 80.3 s−1 and a productivity of 6.1 g L−1 d−1 were achieved. The electrochemical H2O2-stat mode not only offers a promising alternative reaction concept to the well-established galvanostatic mode but also enhances the process performance of unspecific peroxygenases.Publicationtype: Journal ArticleScopus© Citations 1 67 160 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Quantitative and non-quantitative assessments of enzymatic electrosynthesis: A case study of parameter requirements(Wiley, 2023-12-13); ; The integration of enzymatic and electrochemical reactions offers a unique opportunity to optimize production processes. Recently, an increasing number of laboratory-scale enzymatic electrosyntheses have shown impressive performance indicators, leading to scientific interest in technical implementation. However, important process parameters are missing in most of the relevant literature. On one hand, this is due to the large variety of relevant performance indicators. On the other hand, enzyme technologists and electrochemists use different parameters to describe a process. In this article, we review the most important performance indicators in electroenzymatic processes and suggest that in order to allow quantitative comparison, these indicators should be reported in all respective publications. In addition to quantitative parameters, non-quantitative assessments often need to be included in a final evaluation. Examples of such parameters are sustainability, contribution to the UN Sustainable Development Goals or interactions with the overall process. We demonstrate the evaluation of processes using hydrogen peroxide-dependent peroxygenases. The strength of the proposed evaluation system lies in its ability to identify weaknesses in a process at an early stage of development. Finally, it can be concluded that all evaluated enzymatic electrosynthesis do not yet meet typical industrial requirements for an enzyme-based process.Publicationtype: Journal ArticleScopus© Citations 1 36 50 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Application of the all-in-one electrode for in situ H2O2 generation in hydroxylation catalyzed by unspecific peroxygenase from Agrocybe aegerita(2023-08-01); ; ; ; The versatile unspecific peroxygenase from the fungus Agrocybe aegerita (AaeUPO) is capable to perform hydroxylation of various substrates, even unactivated C[sbnd]H bonds. The technical application of AaeUPO is still limited due to an instability towards its co-substrate hydrogen peroxide (H2O2). Electrochemical synthesis of H2O2 is an attractive approach that provides controllable in situ generation of H2O2. The aims of this study are to promote catalyst efficiency and develop an individually tailored system for H2O2-dependent reactions. Herein, an All-in-One electrode (AiO) system with a carbon felt cathode is used to generate H2O2 in situ and combined for the first time with an enzymatic hydroxylation. The AiO electrode combines the counter and working electrode in a single rod structure. This shape provides convenient integration into conventional bioreactors, thus, converting them into bioelectrochemical systems (BES). Hydroxylation of 4-ethylbenzoic acid (EBA) catalyzed by the recombinant AaeUPO (rAaeUPO) was chosen as the model reaction. Total turnover number (TTN) up to 450,000 mol mol−1 and turnover frequency (TOF) up to 7.7 s −1 were achieved using the AiO electrode system. The H2O2 productivity was identified as the limiting factor in the hydroxylation of EBA. However, with numbering-up or surface enlargement, this process could have great potential as an optimizable platform for H2O2-dependent enzymatic reactions.Publicationtype: Journal Article109