TY - JOUR A1 - Tippkötter, Nils A1 - Roikaew, W. A1 - Ulber, R. T1 - Nitrate removal from whey concentrate with biotechnological regeneration of the waste water JF - European dairy magazine : EDM Y1 - 2008 SN - 0936-6318 IS - 1 SP - 30 EP - 32 ER - TY - CHAP A1 - Tippkötter, Nils A1 - Roikaew, W. A1 - Ulber, R. T1 - An automated pilot plant for the bioengineering processing of concentrated whey T2 - European BioPerspectives : in cooperation with BIOTECHNICA 2008 : 7 - 9 October 2008 Hannover, Germany ; book of abstracts ; abstracts, poster programme Y1 - 2008 SP - 98 PB - Dechema CY - Frankfurt am Main ER - TY - JOUR A1 - Tippkötter, Nils A1 - Roikaew, Wipa A1 - Ulber, Roland A1 - Hoffmann, Alexander A1 - Denzler, Hans-Jörg A1 - Buchholz, Heinrich T1 - Paracoccus denitrificans for the effluent recycling during continuous denitrification of liquid food JF - Biotechnology Progress N2 - Nitrate is an undesirable component of several foods. A typical case of contamination with high nitrate contents is whey concentrate, containing nitrate in concentrations up to 25 l. The microbiological removal of nitrate by Paracoccus denitrificans under formation of harmless nitrogen in combination with a cell retention reactor is described here. Focus lies on the resource-conserving design of a microbal denitrification process. Two methods are compared. The application of polyvinyl alcohol-immobilized cells, which can be applied several times in whey feed, is compared with the implementation of a two step denitrification system. First, the whey concentrate's nitrate is removed by ion exchange and subsequently the eluent regenerated by microorganisms under their retention by crossflow filtration. Nitrite and nitrate concentrations were determined by reflectometric color measurement with a commercially available Reflectoquant® device. Correction factors for these media had to be determined. During the pilot development, bioreactors from 4 to 250 mg·L-1 and crossflow units with membrane areas from 0.02 to 0.80 m2 were examined. Based on the results of the pilot plants, a scaling for the exemplary process of denitrifying 1,000 tons per day is discussed. Y1 - 2010 U6 - http://dx.doi.org/10.1002/btpr.384 SN - 8756-7938 VL - 26 IS - 3 SP - 756 EP - 762 PB - Wiley CY - Hoboken, NJ ER - TY - JOUR A1 - Tippkötter, Nils A1 - Roth, Jasmine T1 - Purified Butanol from Lignocellulose – Solvent‐Impregnated Resins for an Integrated Selective Removal JF - Chemie Ingenieur Technik N2 - In traditional microbial biobutanol production, the solvent must be recovered during fermentation process for a sufficient space-time yield. Thermal separation is not feasible due to the boiling point of n-butanol. As an integrated and selective solid-liquid separation alternative, solvent impregnated resins (SIRs) were applied. Two polymeric resins were evaluated and an extractant screening was conducted. Vacuum application with vapor collection in fixed-bed column as bioreactor bypass was successfully implemented as butanol desorption step. In course of further increasing process economics, fermentation with renewable lignocellulosic substrates was conducted using Clostridium acetobutylicum. Utilization of SIR was shown to be a potential strategy for solvent removal from fermentation broth, while application of a bypass column allows for product removal and recovery at once. KW - Biofuel KW - Biorefinery KW - Butanol KW - Clostridium acetobutylicum KW - Lignocellulose Y1 - 2020 U6 - http://dx.doi.org/10.1002/cite.202000200 SN - 1522-2640 VL - 92 IS - 11 SP - 1741 EP - 1751 PB - Wiley-VCH CY - Weinheim ER - TY - CHAP A1 - Tippkötter, Nils A1 - Schünemann, V. A1 - Christmann, R. A1 - Pasteur, A. A1 - Schweizer, J. A1 - Ulber, R. ED - Beckmann, Dieter T1 - Bioaffinity Layering magnetisierbarer Mikro- und Nanopartikel T2 - Technische Systeme für die Lebenswissenschaften : 14. Heiligenstädter Kolloquium, Heilbad Heiligenstadt, 22.09. - 24.09.2008 Y1 - 2008 SN - 978-3-00-025695-0 SP - 97 EP - 98 CY - Heiligenstadt ER - TY - CHAP A1 - Tippkötter, Nils A1 - Stückmann, H. A1 - Winkelmann, G. A1 - Noack, U. A1 - Beutel, S. A1 - Scheper, T. A1 - Ulber, R. T1 - Optimisation of antibody-labelling of gold colloids for their application in an immunchromatographic assay for microcystin-LR T2 - European BioPerspectives : celebrating the 25th DECHEMA annual convention of biotechnologists ; 30 May - 1 June 2007, Cologne, Germany ; book of abstracts ; abstracts, poster programme Y1 - 2007 SP - 126 PB - Dechema CY - Frankfurt am Main ER - TY - JOUR A1 - Tippkötter, Nils A1 - Stückmann, Henning A1 - Kroll, Stephen A1 - Winkelmann, Gunda A1 - Noack, Udo A1 - Scheper, Thomas A1 - Ulber, Roland T1 - A semi-quantitative dipstick assay for microcystin JF - Analytical and Bioanalytical Chemistry N2 - An immunochromatographic lateral flow dipstick assay for the fast detection of microcystin-LR was developed. Colloid gold particles with diameters of 40 nm were used as red-colored antibody labels for the visual detection of the antigen. The new dipstick sensor is capable of detecting down to 5 µg·l−1 (ppb; total inversion of the color signal) or 1 ppb (observation of color grading) of microcystin-LR. The course of the labeling reaction was observed via spectrometric wave shifts caused by the change of particle size during the binding of antibodies. Different stabilizing reagents showed that especially bovine serum albumin (BSA) and casein increase the assays sensitivity and the conjugate stability. Performance of the dipsticks was quantified by pattern processing of capture zone CCD images. Storage stability of dipsticks and conjugate suspensions over 115 days under different conditions were monitored. The ready-to-use dipsticks were successfully tested with microcystin-LR-spiked samples of outdoor drinking- and salt water and applied to the tissue of microcystin-fed mussels. Y1 - 2009 U6 - http://dx.doi.org/10.1007/s00216-009-2750-8 SN - 1618-2650 VL - 394 IS - 3 SP - 863 EP - 869 PB - springer CY - Berlin ER - TY - RPRT A1 - Tippkötter, Nils A1 - Wagner, Sebastian T1 - Biomimetischer Klebstoff aus ligninhaltigen Pflanzenresten (Teilvorhaben 1 und 2) : Schlussbericht zum Vorhaben : Laufzeit: 01.01.2016 bis 31.03.2019 Y1 - 2019 U6 - http://dx.doi.org/10.2314/KXP:169732777X N1 - Förderkennzeichen BMEL 22030514 - 22004615 PB - FH Aachen CY - Jülich ER - TY - JOUR A1 - Tippkötter, Nils A1 - Wollny, S. A1 - Kampeis, P. A1 - Oster, J. A1 - Schneider, H. A1 - Ulber, R. T1 - Magnetseparation von Proteinen : Separation von Zielmolekülen durch hochselektive Aptamere JF - GIT Labor-Fachzeitschrift N2 - Durch die Kombination von Oligonukleotid-Liganden (Aptameren) hoher Bindungsaffinitäten mit hochselektiv abtrennbaren magnetisierbaren Mikropartikeln wird eine einstufige Separation von Zielmolekülen aus mikrobiologischen Produktionsansätzen möglich. Die Aptamere werden hierfür reversibel auf den Partikeloberflächen gebunden und für die spezifische Isolierung von Bioprodukten eingesetzt. Die Abtrennung der beladenen Partikel erfolgt durch einen neuen Rotor-Stator-Separator mit Hochgradient-Magnetfeld. Y1 - 2011 VL - 55 IS - 10 SP - 666 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Tippkötter, Nils A1 - Wollny, Steffen A1 - Suck, Kirstin A1 - Sohling, Ulrich A1 - Ruf, Friedrich A1 - Ulber, Roland T1 - Recycling of spent oil bleaching earth as source of glycerol for the anaerobic production of acetone, butanol, and ethanol with Clostridium diolis and lipolytic Clostridium lundense JF - Engineering in Life Sciences N2 - A major part of edible oil is subjected to bleaching procedures, primarily with minerals applied as adsorbers. Their recycling is currently done either by regaining the oil via organic solvent extraction or by using the spent bleaching earth (SBE) as additive for animal feed, etc. As a new method, the reutilization of the by-product SBE for the microbiologic formation of acetone, butanol, and ethanol (ABE) is presented as proof-of-concept. The SBE was taken from a palm oil cleaning process. The recycling concept is based on the application of lipolytic clostridia strains. Due to considerably long fermentation times, co-fermentation with Candida rugosa and enzymatic hydrolyses of the bound oil with a subsequent clostridia fermentation are shown as alternative routes. Anaerobic fermentations under comparison of different clostridia strains were performed with glycerol media, enzymatically hydrolyzed palm oil and SBE. Solutes, side product compositions and productivities were quantified via HPLC. A successful production of ABE solutes from SBE has been done with a yield of 0.15 g butanol per gram of bound glycerol. Thus, the biotechnological recycling of the waste stream is possible in principle. Inhibition of the substrate suspension has been observed. A chromatographic ion-exchange of substrates increased the biomass concentration. Y1 - 2014 U6 - http://dx.doi.org/10.1002/elsc.201300113 SN - 1618-2863 VL - 14 IS - 4 SP - 425 EP - 432 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Tran, Quang Hon A1 - Bongaerts, Johannes A1 - Vlad, Dorina A1 - Unden, Gottfried T1 - Requirement for the proton-pumping NADH dehydrogenase I of Escherichia coli in respiration of NADH to fumarate and its bioenergetic implications JF - European journal of biochemistry Y1 - 1997 SN - 0014-2956 VL - Vol. 244 IS - Iss. 1 SP - 155 EP - 160 ER - TY - JOUR A1 - Trapp, Svenja A1 - Lammers, Tom A1 - Engudar, Gokce A1 - Hoehr, Cornelia A1 - Denkova, Antonia G. A1 - Paulßen, Elisabeth A1 - de Kruijff, Robin M. T1 - Membrane-based microfluidic solvent extraction of Ga-68 from aqueous Zn solutions: towards an automated cyclotron production loop JF - EJNMMI Radiopharmacy and Chemistry KW - Microfluidic solvent extraction KW - Ga-68 KW - Cyclotron production KW - Medical radionuclide production KW - Metal contaminants Y1 - 2023 U6 - http://dx.doi.org/10.1186/s41181-023-00195-2 SN - 2365-421X VL - 2023 IS - 8, Article number: 9 SP - 1 EP - 14 PB - Springer Nature ER - TY - JOUR A1 - Turck, Christoph W. A1 - Berndt, Heinz T1 - Synthese definierter Peptid-Derivate durch Aminolyse von 3-(Nα-Acyl-peptidyloxy)-2-hydroxy-N-alkylbenzamiden bei erhöhten Temperaturen, I : Synthese des Modellpeptid-Derivates Z-Ala-Phe-Gly-N(Et)2 JF - Hoppe-Seyler´s Zeitschrift für physiologische Chemie Y1 - 1981 U6 - http://dx.doi.org/10.1515/bchm2.1981.362.1.821 SN - 1437-4315 SN - 0018-4888 VL - 362 IS - 1 SP - 821 EP - 828 ER - TY - JOUR A1 - Turek, Monika A1 - Ketterer, Lothar A1 - Claßen, Melanie A1 - Berndt, Heinz A1 - Elbers, Gereon A1 - Krüger, Peter A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Development and Electrochemical Investigations of an EIS-(Electrolyte-Insulator-Semiconductor) based Biosensor for Cyanide Detection JF - Sensors Y1 - 2007 SN - 1424-8220 VL - 7 IS - 8 SP - 1415 EP - 1426 ER - TY - JOUR A1 - Tüg, Helmut A1 - Baumann, Marcus T1 - Problems of UV-B radiation measurements in biological research : critical remarks on current techniques and suggestions for improvements JF - Geophysical research letters Y1 - 1994 SN - 1944-8007 (E-Journal); 0094-8276 (Print) VL - Vol. 21 IS - Iss. 8 SP - 689 EP - 692 ER - TY - JOUR A1 - Tüg, Helmut A1 - Baumann, Marcus T1 - Reply to the comments by R.L. McKenzie and P.V. Johnston on our paper “Problems of UV-B radiation measurements in biological research: Critical Remarks on current techniques and suggestions for improvements” JF - Geophysical research letters Y1 - 1995 SN - 1944-8007 (E-Journal); 0094-8276 (Print) VL - Vol. 22 IS - Iss. 9 SP - 1159 EP - 1160 ER - TY - JOUR A1 - Ulber, R. A1 - Tippkötter, Nils A1 - Buchholz, H. A1 - Demmer, W. A1 - Scheper, T. T1 - Innovative Verfahren in der Molkeaufarbeitung zur Gewinnung neuer Produkte JF - Deutsche Milchwirtschaft Y1 - 2008 SN - 0012-0480 VL - 59 IS - 19 SP - 704 EP - 706 ER - TY - CHAP A1 - Ulber, Roland A1 - Muffler, Kai A1 - Tippkötter, Nils A1 - Hirth, Thomas A1 - Sell, Dieter ED - Ulber, Roland ED - Sell, Dieter ED - Hirth, Thomas T1 - Introduction to Renewable Resources in the Chemical Industry T2 - Renewable raw materials : new feedstocks for the chemical industry Y1 - 2011 SN - 978-3-527-32548-1 SP - 1 EP - 6 PB - Wiley-VCH-Verlag CY - Weinheim ET - 1. Auflage ER - TY - JOUR A1 - Ulber, Roland A1 - Poth, Sebastian A1 - Monzon, Magaly A1 - Tippkötter, Nils T1 - Prozessintegration von Hydrolyse und Fermentation von Cellulose- Faserstoff JF - Chemie Ingenieur Technik N2 - Ein viel versprechender erneuerbarer Rohstoff für die Produktion von Chemikalien und Treibstoffen ist Lignocellulose aus pflanzlicher Biomasse. Die darin enthaltenen Zucker können mittels enzymatischer Hydrolyse freigesetzt und fermentativ zu Ethanol umgesetzt werden. Ein interessanter Ansatz ist dabei die simultane Verzuckerung und Fermentation. Hefen und Enzyme haben mit 30 °C bzw. 50 °C zwar unterschiedliche Temperaturoptima, es konnte aber gezeigt werden, dass auch bei den niedrigeren Temperaturen eine Umsetzung der Cellulose zu Glucose erfolgt, wenn auch langsamer als bei optimalen Bedingungen. Außerdem konnte in Vorversuchen gezeigt werden, dass Ethanol in den zu erwartenden Konzentrationen keinen Einfluss auf die enzymatische Umsetzung hat. Y1 - 2010 U6 - http://dx.doi.org/10.1002/cite.200900103 SN - 1522-2640 N1 - Special Issue "Biokatalyse" VL - 82 IS - 1-2 SP - 135 EP - 139 ER - TY - JOUR A1 - Ulber, Roland A1 - Tippkötter, Nils T1 - Nitratfreie Molke JF - Rundschau für Fleischhygiene und Lebensmittelüberwachung Y1 - 2009 IS - 4 SP - 150 EP - 152 ER -