TY - JOUR A1 - Thiel, Alexander A1 - Tippkötter, Nils A1 - Suck, Kirstin A1 - Sohling, Ulrich A1 - Ruf, Friedrich A1 - Ulber, Roland T1 - New zeolite adsorbents for downstream processing of polyphenols from renewable resources JF - Engineering in Life Sciences N2 - Commercial materials with polyvinylpolypyrrolidone and polymeric amberlites (XAD7HP, XAD16) are commonly used for the adsorptive downstream processing of polyphenols from renewable resources. In this study, beta-zeolite-based adsorbent systems were examined, and their properties were compared to organic resins. Batch adsorption experiments were conducted with synthetic solutions of major polyphenols. Adsorption isotherms and desorption characteristics of individual adsorbent were determined based on these results. Maximum adsorption capacities were calculated using the Langmuir model. For example, the zeolites had capacities up to 203.2 mg/g for ferulic acid. To extend these results to a complex system, additional experiments were performed on rapeseed meal and wheat seed extracts as representative renewable resources. HPLC analysis showed that with 7.5% w/v, which is regarded as the optimum amount of zeolites, zeolites A and B could bind 100% of the major polyphenols as well as release polyphenols at high yields. Additionally, regeneration experiments were performed with isopropyl alcohol at 99°C to evaluate how zeolites regenerate under mild conditions. The results showed only a negligible loss of adsorption capacity and no loss of desorption capacity. In summary, it was concluded that beta-zeolites were promising adsorbents for developing new processes to isolate polyphenols from renewable resources. Y1 - 2013 U6 - http://dx.doi.org/10.1002/elsc.201200188 VL - 13 IS - 3 SP - 239 EP - 246 PB - Wiley CY - Weinheim ER - TY - CHAP A1 - Tippkötter, Nils ED - Kaltschmidt, Martin T1 - Grundlagen der bio-chemischen Umwandlung T2 - Energie aus Biomasse : Grundlagen, Techniken und Verfahren Y1 - 2016 SN - 978-3-662-47437-2 (Print) SN - 978-3-662-47438-9 (Online) U6 - http://dx.doi.org/10.1007/978-3-662-47438-9 SP - 1447 EP - 1500 PB - Springer Vieweg CY - Berlin ; Heidelberg ET - 3., aktualisierte, erweiterte Auflage ER - TY - BOOK A1 - Tippkötter, Nils T1 - Reaktionssysteme zur Aufarbeitung und Umsetzung nachwachsender Rohstoffe : Einsatz chromatographischer Verfahren sowie Membran- und Festbettreaktoren zur Verarbeitung von Molke, Stärke und Cellulose Y1 - 2010 SN - 978-3-8325-2717-4 N1 - Kaiserslautern, Technische Universität, Dissertation, 2010 PB - Logos-Verlag CY - Berlin ER - TY - CHAP A1 - Tippkötter, Nils T1 - Biotechnologische Gewinnung von Wertstoffen aus Molke : BiobasedWorld - Innovation in food T2 - Biotechnica 2013 : European biotechnology science & industry news Y1 - 2013 VL - 12 IS - 9, special SP - 33 EP - 50 ER - TY - RPRT A1 - Tippkötter, Nils T1 - Lokale Vorbehandlung nachwachsender Rohstoffe für Bioraffinerien (BioSats) : Schlussbericht zum Vorhaben : Laufzeit: 01.03.2012 bis 30.04.2017 Y1 - 2018 U6 - http://dx.doi.org/10.2314/GBV:1024204243 ER - TY - JOUR A1 - Tippkötter, Nils A1 - Al-Kaidy, Huschyar A1 - Wollny, Steffen A1 - Ulber, Roland T1 - Functionalized magnetizable particles for downstream processing in single-use systems JF - Chemie Ingenieur Technik N2 - Biotechnological downstream processing is usually an elaborate procedure, requiring a multitude of unit operations to isolate the target component. Besides the disadvantageous space-time yield, the risks of cross-contaminations and product loss grow fast with the complexity of the isolation procedure. A significant reduction of unit operations can be achieved by application of magnetic particles, especially if these are functionalized with affinity ligands. As magnetic susceptible materials are highly uncommon in biotechnological processes, target binding and selective separation of such particles from fermentation or reactions broths can be done in a single step. Since the magnetizable particles can be produced from iron salts and low priced polymers, a single-use implementation of these systems is highly conceivable. In this article, the principles of magnetizable particles, their synthesis and functionalization are explained. Furthermore, applications in the area of reaction engineering, microfluidics and downstream processing are discussed focusing on established single-use technologies and development potential. Y1 - 2013 U6 - http://dx.doi.org/10.1002/cite.201200130 VL - 85 IS - 1-2: Special Issue: Single-Use Technology SP - 76 EP - 86 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Tippkötter, Nils A1 - Deterding, A. A1 - Ulber, Roland T1 - Determination of acetic acid in fermentation broth by gas-diffusion technique JF - Engineering in Life Sciences N2 - Due to the interfering effects of acetic acid in many fermentation processes, a gas-diffusion technique was developed for the online determination of acetic acid. The measurements were accomplished with a flow diffusion analysis (FDA) unit from the TRACE Analytics GmbH, Braunschweig, Germany. The diffusion analysis is based on the UV-absorbance of acetic acid at 205 nm. The measurement was achieved by the separation of an acceptor and a carrier stream (acidified fermentation broth) using a gas permeable polytetrafluoroethylene (PTFE) membrane, whereby broth constituents that would otherwise disturb the UV-measurement of acetic acid, are held back efficiently. Merely, the fermentation by-products, e.g. formic acid, is capable of diffusing through the membrane. While formic acid can disturb the measurement, carbon dioxide does not absorb at 205 nm. The method operates with time-dependent sample enrichment. During the analysis, a small volume of the acceptor stream is stopped for a defined time interval in the acceptor chamber. During this period, the gaseous acetic acid diffuses through the membrane and is enriched in the acceptor chamber. Subsequently after the enrichment, the acceptor stream flows through a UV-detector. The intensity of the signal is proportional to the acetic acid concentration. Online measurements in bioreactors via a sterile filtration probe have been accomplished. A linear calibration in the range of 0.5–5.0 g/L acetic acid with a relative standard deviation of <5 % was obtained. A sampling rate of 8 samples per hour was possible. The system was applied for the determination of acetic acid in E. coli fermentation broth. The instrument is easy to clean, very user-friendly and does not require any toxic or expensive reagents. Y1 - 2008 U6 - http://dx.doi.org/10.1002/elsc.200820227 VL - 8 IS - 1, Special Issue: Technical Systems for the Use in Life Sciences SP - 62 EP - 67 ER - TY - JOUR A1 - Tippkötter, Nils A1 - Duwe, Anna-Maria A1 - Wiesen, Sebastian A1 - Sieker, Tim A1 - Ulber, Roland T1 - Enzymatic hydrolysis of beech wood lignocellulose at high solid contents and its utilization as substrate for the production of biobutanol and dicarboxylic acids JF - Bioresource Technology N2 - The development of a cost-effective hydrolysis for crude cellulose is an essential part of biorefinery developments. To establish such high solid hydrolysis, a new solid state reactor with static mixing is used. However, concentrations >10% (w/w) cause a rate and yield reduction of enzymatic hydrolysis. By optimizing the synergetic activity of cellulolytic enzymes at solid concentrations of 9%, 17% and 23% (w/w) of crude Organosolv cellulose, glucose concentrations of 57, 113 and 152 g L⁻¹ are reached. However, the glucose yield decreases from 0.81 to 0.72gg⁻¹ at 17% (w/w). Optimal conditions for hydrolysis scale-up under minimal enzyme addition are identified. As result, at 23% (w/w) crude cellulose the glucose yield increases from 0.29 to 0.49gg⁻¹. As proof of its applicability, biobutanol, succinic and itaconic acid are produced with the crude hydrolysate. The potential of the substrate is proven e.g. by a high butanol yield of 0.33gg⁻¹. Y1 - 2014 U6 - http://dx.doi.org/10.1016/j.biortech.2014.06.052 VL - 167 SP - 447 EP - 455 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Tippkötter, Nils A1 - Möhring, S. A1 - Maurer, S. A1 - Roth, J. T1 - Dezentrale Vorbehandlung und Verarbeitung pflanzlicher Reststoffe für Bioraffinerien T2 - Kurzfassungen der Vorträge nach Sessions : Frühjahrstagung der Biotechnologen 2013, 4. - 5. März 2013, Dechema-Haus, Frankfurt am Main Y1 - 2013 SP - 5 CY - Frankfurt am Main ER - TY - CHAP A1 - Tippkötter, Nils A1 - Möhring, Sophie A1 - Roth, Jasmine A1 - Wulfhorst, Helene T1 - Logistics of lignocellulosic feedstocks: preprocessing as a preferable option T2 - Biorefineries N2 - In comparison to crude oil, biorefinery raw materials are challenging in concerns of transport and storage. The plant raw materials are more voluminous, so that shredding and compacting usually are necessary before transport. These mechanical processes can have a negative influence on the subsequent biotechnological processing and shelf life of the raw materials. Various approaches and their effects on renewable raw materials are shown. In addition, aspects of decentralized pretreatment steps are discussed. Another important aspect of pretreatment is the varying composition of the raw materials depending on the growth conditions. This problem can be solved with advanced on-site spectrometric analysis of the material. KW - Analytics KW - Decentral KW - Mechanical KW - On-site KW - Pre-treatment Y1 - 2019 SN - 978-3-319-97117-9 SN - 978-3-319-97119-3 U6 - http://dx.doi.org/10.1007/10_2017_58 N1 - Advances in biochemical engineering/biotechnology ; Vol. 166 SP - 43 EP - 68 PB - Springer CY - Cham ER -