@article{ThielMufflerTippkoetteretal.2015,
  author    = {Thiel, Alexander and Muffler, Kai and Tippk{\"o}tter, Nils and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland},
  title     = {Aufarbeitung von Polyphenolen aus Weizen mittels Zeolithen am Beispiel der Ferulas{\"a}ure},
  series = {Chemie IngenieurTechnik},
  volume    = {87},
  journal   = {Chemie IngenieurTechnik},
  number    = {1-2},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/cite.201400031},
  pages     = {128 -- 136},
  year      = {2015},
  abstract  = {Aufarbeitung von Polyphenolen aus Weizenmittels Zeolithen am Beispiel der Ferulasa¨ ureAlexander Thiel1, Kai Muffler1, Nils Tippko¨ tter1, Kirstin Suck2, Ulrich Sohling2, Friedrich Ruf3und Roland Ulber1,*DOI: 10.1002/cite.201400031Bei der Ferulasa¨ure handelt es sich um einen Wertstoff, der aus Weizen gewonnen und in der Lebensmittel- und Pharma-industrie eingesetzt werden kann. Der Einsatz von Weizen als nachwachsende Rohstoffquelle ist allerdings nur dann wirt-schaftlich durchfu¨hrbar, wenn eine Prozessintegration in die bestehenden industriellen Verfahren gewa¨hrleistet oder einedirekte Konkurrenz zur Mehl- und Sta¨rkeindustrie vermieden werden kann. In diesem Artikel wird ein Verfahren aufge-zeigt, welches hohe Ausbeuten ermo¨glicht und eine Konkurrenz zu bestehenden Verwertungspfaden vermeidet.},
  language  = {de}
}
@article{ThielTippkoetterSucketal.2013,
  author    = {Thiel, Alexander and Tippk{\"o}tter, Nils and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland},
  title     = {New zeolite adsorbents for downstream processing of polyphenols from renewable resources},
  series = {Engineering in Life Sciences},
  volume    = {13},
  journal   = {Engineering in Life Sciences},
  number    = {3},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/elsc.201200188},
  pages     = {239 -- 246},
  year      = {2013},
  abstract  = {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.},
  language  = {en}
}
@incollection{Tippkoetter2016,
  author    = {Tippk{\"o}tter, Nils},
  title     = {Grundlagen der bio-chemischen Umwandlung},
  series = {Energie aus Biomasse : Grundlagen, Techniken und Verfahren},
  booktitle = {Energie aus Biomasse : Grundlagen, Techniken und Verfahren},
  editor    = {Kaltschmidt, Martin},
  edition   = {3., aktualisierte, erweiterte Auflage},
  publisher = {Springer Vieweg},
  address   = {Berlin ; Heidelberg},
  isbn      = {978-3-662-47437-2 (Print)},
  doi       = {10.1007/978-3-662-47438-9},
  pages     = {1447 -- 1500},
  year      = {2016},
  language  = {de}
}
@book{Tippkoetter2010,
  author    = {Tippk{\"o}tter, Nils},
  title     = {Reaktionssysteme zur Aufarbeitung und Umsetzung nachwachsender Rohstoffe : Einsatz chromatographischer Verfahren sowie Membran- und Festbettreaktoren zur Verarbeitung von Molke, St{\"a}rke und Cellulose},
  publisher = {Logos-Verlag},
  address   = {Berlin},
  isbn      = {978-3-8325-2717-4},
  pages     = {III, 269 Seiten},
  year      = {2010},
  language  = {de}
}
@inproceedings{Tippkoetter2013,
  author    = {Tippk{\"o}tter, Nils},
  title     = {Biotechnologische Gewinnung von Wertstoffen aus Molke : BiobasedWorld - Innovation in food},
  series = {Biotechnica 2013 : European biotechnology science \& industry news},
  volume    = {12},
  booktitle = {Biotechnica 2013 : European biotechnology science \& industry news},
  number    = {9, special},
  pages     = {33 -- 50},
  year      = {2013},
  language  = {de}
}
@techreport{Tippkoetter2018,
  author    = {Tippk{\"o}tter, Nils},
  title     = {Lokale Vorbehandlung nachwachsender Rohstoffe f{\"u}r Bioraffinerien (BioSats) : Schlussbericht zum Vorhaben : Laufzeit: 01.03.2012 bis 30.04.2017},
  organization    = {Technische Universit{\"a}t Kaiserslautern},
  doi       = {10.2314/GBV:1024204243},
  pages     = {191 Seiten},
  year      = {2018},
  language  = {de}
}
@article{TippkoetterAlKaidyWollnyetal.2013,
  author    = {Tippk{\"o}tter, Nils and Al-Kaidy, Huschyar and Wollny, Steffen and Ulber, Roland},
  title     = {Functionalized magnetizable particles for downstream processing in single-use systems},
  series = {Chemie Ingenieur Technik},
  volume    = {85},
  journal   = {Chemie Ingenieur Technik},
  number    = {1-2: Special Issue: Single-Use Technology},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/cite.201200130},
  pages     = {76 -- 86},
  year      = {2013},
  abstract  = {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.},
  language  = {en}
}
@article{TippkoetterDeterdingUlber2008,
  author    = {Tippk{\"o}tter, Nils and Deterding, A. and Ulber, Roland},
  title     = {Determination of acetic acid in fermentation broth by gas-diffusion technique},
  series = {Engineering in Life Sciences},
  volume    = {8},
  journal   = {Engineering in Life Sciences},
  number    = {1, Special Issue: Technical Systems for the Use in Life Sciences},
  doi       = {10.1002/elsc.200820227},
  pages     = {62 -- 67},
  year      = {2008},
  abstract  = {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.},
  language  = {en}
}
@article{TippkoetterDuweWiesenetal.2014,
  author    = {Tippk{\"o}tter, Nils and Duwe, Anna-Maria and Wiesen, Sebastian and Sieker, Tim and Ulber, Roland},
  title     = {Enzymatic hydrolysis of beech wood lignocellulose at high solid contents and its utilization as substrate for the production of biobutanol and dicarboxylic acids},
  series = {Bioresource Technology},
  volume    = {167},
  journal   = {Bioresource Technology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  doi       = {10.1016/j.biortech.2014.06.052},
  pages     = {447 -- 455},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}
@inproceedings{TippkoetterMoehringMaureretal.2013,
  author    = {Tippk{\"o}tter, Nils and M{\"o}hring, S. and Maurer, S. and Roth, J.},
  title     = {Dezentrale Vorbehandlung und Verarbeitung pflanzlicher Reststoffe f{\"u}r Bioraffinerien},
  series = {Kurzfassungen der Vortr{\"a}ge nach Sessions : Fr{\"u}hjahrstagung der Biotechnologen 2013, 4. - 5. M{\"a}rz 2013, Dechema-Haus, Frankfurt am Main},
  booktitle = {Kurzfassungen der Vortr{\"a}ge nach Sessions : Fr{\"u}hjahrstagung der Biotechnologen 2013, 4. - 5. M{\"a}rz 2013, Dechema-Haus, Frankfurt am Main},
  address   = {Frankfurt am Main},
  pages     = {5},
  year      = {2013},
  language  = {de}
}