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Publikation Continuous in situ lactic acid extraction from sweet whey fermentation broth using a tubular membrane contactor(2022) Demmelmayer, Paul; Pérez, Alan; Riedl, Wolfgang; Kienberger, MarleneBackground Whey, as the major dairy by-product, has become a severe problem for the dairy industry because its demand has decreased, while its production has increased in the past years. Since the high demand for dairy products tends to further increase, suitable routes for whey valorization are required. Whey contains valuables like lactate, but due its composition matrix, processing is challenging. The high sugar content in whey makes it a potential feedstock to produce lactic acid (LA) via microbial fermentation. Still, the known drawbacks of biotechnological LA production, such as growth inhibition by the product, the use of neutralizers, low productivity, and high overall costs of the process must be overcome. In situ LA recovering using a suitable separation technology is a potential strategy to overcome the mentioned drawbacks. In this work, the in situ LA extraction from a whey fermentation broth was evaluated. Sweet whey was used as feedstock for lactic acid production via microbial fermentation, while LA was recovered by reactive liquid-liquid extraction using a tubular membrane contactor. Method The feed material used in this work is a fermentation broth from sweet whey, which was filtered prior to extraction experiments using microfiltration. In a first series of experiments, two-phase extraction experiments were conducted in temperature controlled separation funnels, to investigate different solvent phase combinations for the lactic acid extraction. Special attention was paid to replace commonly applied fossil-based solvents with green alternatives, such as deep eutectic solvents (DES). After extraction, the extract was treated in a back-extraction step to recover LA from the solvent phase. Here, an anti-solvent, e.g. heptane or p-cymene, was used to transfer LA to the receiving phase, which was water. Afterwards the performance of reactive liquid-liquid extraction of LA using a PTFE membrane contactor was evaluated by using two potential solvent phases, namely tri-n-octyl amine (TOA) with n-decanol and a DES formed from thymol and menthol. From the experimental results the overall mass transfer coefficient was calculated based on a rigorous mass transfer model to predict the LA concentration in both phases. Finally, performance of the in situ LA recovery from sweet whey by using membrane contactor was investigated from both, experimentally and theoretically points of view. Results & Conclusion In the two-phase extraction experiments, the reactive extractants Aliquat336, TOA, trioctylphosphinoxid (TOPO), and the mixture Aliquat336/TOA were found to be most efficient with the diluents 1-decanol, limonene, and a deep eutectic solvent consisting of thymol and menthol. Especially, the DES and limonene are promising as they can be produced from renewable resources. With respect to back-extraction, heptane and p-cymene showed the highest efficiencies for transferring lactic acid into the receiving phase water. In the next step, the selected solvents were used to perform LA recovery in the tubular membrane contactor from a model aqueous solution of LA and a fermentation broth of sweet whey. The proposed technology for valorizing dairy waste through LA biotechnological production shows the feasibility to scaling it up.06 - PräsentationPublikation Prozessoptimierung von 4 Stufen zur Herstellung eines Pharma-Zwischenprodukts(Hochschule für Life Sciences FHNW, 2024) Güner, Merve; Zogg, Andreas11 - Studentische ArbeitPublikation Development of a tool for the automated visualization of batch recipes(Hochschule für Life Sciences FHNW, 2024) Gentner, Jannick; Zogg, Andreas; Bachem AG11 - Studentische ArbeitPublikation Kontinuierliche Ethoxylierung(25.04.2024) Zogg, Andreas; Zahnd, This; Brönnimann, BenediktModellbasiertes Sicherheitskonzept für die Entwicklung einer kontinuierlichen Ethoxylierung. Modellvalidierung mittels kontinuierlichem Kalorimeter innerhalb einer Glove-Box.06 - PräsentationPublikation Enzymes for consumer products to achieve climate neutrality(Oxford University Press, 2023) Molina-Espeja, Patricia; Sanz-Aparicio, Julia; Golyshin, Peter N.; Robles-Martín, Ana; Guallar, Víctor; Beltrametti, Fabrizio; Müller, Markus; Yakimov, Michail M.; Modregger, Jan; van Logchem, Moniec; Corvini, Philippe; Shahgaldian, Patrick; Degering, Christian; Wieland, Susanne; Timm, Anne; de Carvalho, Carla C. C. R.; Re, Ilaria; Daniotti, Sara; Thies, Stephan; Jaeger, Karl-Erich; Chow, Jennifer; Streit, Wolfgang R.; Lottenbach, Roland; Rösch, Rainer; Ansari, Nazanin; Ferrer, ManuelToday, the chemosphere’s and biosphere’s compositions of the planet are changing faster than experienced during the past thousand years. CO2 emissions from fossil fuel combustion are rising dramatically, including those from processing, manufacturing and consuming everyday products; this rate of greenhouse gas emission (36.2 gigatons accumulated in 2022) is raising global temperatures and destabilizing the climate, which is one of the most influential forces on our planet. As our world warms up, our climate will enter a period of constant turbulence, affecting more than 85% of our ecosystems, including the delicate web of life on these systems, and impacting socioeconomic networks. How do we deal with the green transition to minimize climate change and its impacts while we are facing these new realities? One of the solutions is to use renewable natural resources. Indeed, nature itself, through the working parts of its living systems, the enzymes, can significantly contribute to achieve climate neutrality and good ecological/biodiversity status. Annually they can help decreasing CO2 emissions by 1–2.5 billion-tons, carbon demand by about 200 million-tons, and chemical demand by about 90 million-tons. With current climate change goals, we review the consequences of climate change at multiple scales and how enzymes can counteract or mitigate them. We then focus on how they mobilize sustainable and greener innovations in consumer products that have a high contribution to global carbon emissions. Finally, key innovations and challenges to be solved at the enzyme and product levels are discussed.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Modeling-based approach towards quality by design for a telescoped process(Schweizerische Chemische Gesellschaft, 2024) Zahnd, This; Kandziora, Maja; Levis, Michael K.; Zogg, AndreasA telescoped, two-step synthesis was investigated by applying Quality by Design principles. A kinetic model consisting of 12 individual reactions was successfully established to describe the synthesis and side reactions. The resulting model predicts the effects of changes in process parameters on total yield and quality. Contour plots were created by varying process parameters and displaying the model predicted process response. The areas in which the process response fulfils predetermined quality requirements are called design spaces. New ranges for process parameters were explored within these design spaces. New conditions were found that increased the robustness of the process and allowed for a considerable reduction of the used amounts of a reagent. Further optimizations, based on the newly generated knowledge, are expected. Improvements can either be direct process improvements or enhancements to control strategies. The developed strategies can also be applied to other processes, enhancing upcoming and preexisting research and development efforts.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Development of a novel measurement setup to study and predict electrostatic discharges in agitated glass‐lined vessels(Wiley, 12.02.2024) Brönnimann, Benedikt; Egli‐Tedesco, Daniel; Schwenzfeuer, Klaus; Zogg, AndreasTwo glass lined reactors in a launch platform facility operated by Syngenta have been damaged during the crystallization of an organic compound due to electrostatic discharges. The goal of this work was to design and commission a novel setup to measure charges and currents generated by this slurry in a laboratory‐scale reactor. An improved and more sophisticated setup was then proposed for possible implementation in Syngenta's own laboratories. With this novel setup, the electrostatic charging of stirred suspensions involving nonconductive solvents could be accurately measured in the context of a case study that involved the suspension that led to liner damages in the production facilities of Syngenta.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Transforming an esterase into an enantioselective catecholase through bioconjugation of a versatile metal-chelating inhibitor(Royal Society of Chemistry, 2023) Fernandez-Lopez, Laura; Cea-Rama, Isabel; Alvarez-Malmagro, Julia; Ressmann, Anna K.; Gonzalez-Alfonso, Jose L.; Coscolín, Cristina; Shahgaldian, Patrick; Plou, Francisco J.; Modregger, Jan; Pita, Marcos; Sanz-Aparicio, Julia; Ferrer, ManuelMetal complexes introduced into esterase enzyme scaffolds can generate versatile biomimetic catalysts endowed with oxidoreductase activity.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Nanobiocatalysts with inbuilt cofactor recycling for oxidoreductase catalysis in organic solvents(Royal Society of Chemistry, 2023) Sahlin, Jenny; Wu, Congyu; Buscemi, Andrea; Schärer, Claude; Nazemi, Seyed Amirabbas; S. K., Rejaul; Herrera-Reinoza, Nataly; Jung, Thomas A.; Shahgaldian, PatrickThe major stumbling block in the implementation of oxidoreductase enzymes in continuous processes is their stark dependence on costly cofactors that are insoluble in organic solvents. We describe a chemical strategy that allows producing nanobiocatalysts, based on an oxidoreductase enzyme, that performs biocatalytic reactions in hydrophobic organic solvents without external cofactors. The chemical design relies on the use of a silica-based carrier nanoparticle, of which the porosity can be exploited to create an aqueous reservoir containing the cofactor. The nanoparticle core, possessing radial-centred pore channels, serves as a cofactor reservoir. It is further covered with a layer of reduced porosity. This layer serves as a support for the immobilisation of the selected enzyme yet allowing the diffusion of the cofactor from the nanoparticle core. The immobilised enzyme is, in turn, shielded by an organosilica layer of controlled thickness fully covering the enzyme. Such produced nanobiocatalysts are shown to catalyse the reduction of a series of relevant ketones into the corresponding secondary alcohols, also in a continuous flow fashion. © 2023 RSC.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation How technical innovations may help to prevent drug shortages in switzerland(Schweizerische Chemische Gesellschaft, 2023) Gygax, Daniel; Eigenmann, Kaspar; Suter, Christian; Hürzeler Müller, Marianne; Mahmoud, Ahmed; Mosbacher, Johannes; Pöllinger, NorbertIn this work, we investigated the technical feasibility of 'on-demand' production of selected drugs to cover their demand for a time window of 90 days. We focused on two sub-processes 'automated chemical synthesis' and 'formulation in micropellets' to enable personalized dosing. The production of drugs 'on-demand' is challenging, important, but also attractive. Switzerland could thus gain access to an additional instrument for increasing resilience for supply-critical drugs. The biggest challenge in the case study presented here is the scalability of automated chemical synthesis and the application range of micropellet formulations.01A - Beitrag in wissenschaftlicher Zeitschrift