@article{TakenagaBiselliSchnitzleretal.2014, author = {Takenaga, Shoko and Biselli, Manfred and Schnitzler, Thomas and {\"O}hlschl{\"a}ger, Peter and Wagner, Torsten and Sch{\"o}ning, Michael Josef}, title = {Toward multi-analyte bioarray sensors: LAPS-based on-chip determination of a Michaelis-Menten-like kinetics for cell culturing}, series = {Physica status solidi A : Applications and materials science}, volume = {211}, journal = {Physica status solidi A : Applications and materials science}, number = {6}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-396X (E); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)}, doi = {10.1002/pssa.201330464}, pages = {1410 -- 1415}, year = {2014}, abstract = {The metabolic activity of Chinese hamster ovary (CHO) cells was observed using a light-addressable potentiometric sensor (LAPS). The dependency toward different glucose concentrations (17-200 mM) follows a Michaelis-Menten kinetics trajectory with Kₘ = 32.8 mM, and the obtained Kₘ value in this experiment was compared with that found in literature. In addition, the pH shift induced by glucose metabolism of tumor cells transfected with the HPV-16 genome (C3 cells) was successfully observed. These results indicate the possibility to determine the tumor cells metabolism with a LAPS-based measurement device.}, 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} } @article{TippkoetterWollnySucketal.2014, author = {Tippk{\"o}tter, Nils and Wollny, Steffen and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland}, title = {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}, series = {Engineering in Life Sciences}, volume = {14}, journal = {Engineering in Life Sciences}, number = {4}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1618-2863}, doi = {10.1002/elsc.201300113}, pages = {425 -- 432}, year = {2014}, abstract = {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.}, language = {en} } @article{WangDruckenmuellerElbersetal.2014, author = {Wang, Ren-Qi and Druckenm{\"u}ller, Katharina and Elbers, Gereon and Guenther, Klaus and Crou{\´e}, Jean-Philippe}, title = {Analysis of aquatic-phase natural organic matter by optimized LDI-MS method}, series = {Journal of mass spectrometry}, volume = {49}, journal = {Journal of mass spectrometry}, number = {2}, publisher = {Wiley}, address = {Bognor Regis}, issn = {1096-9888}, doi = {10.1002/jms.3321}, pages = {154 -- 160}, year = {2014}, abstract = {The composition and physiochemical properties of aquatic-phase natural organic matter (NOM) are most important problems for both environmental studies and water industry. Laser desorption/ionization (LDI) mass spectrometry facilitated successful examinations of NOM, as humic and fulvic acids in NOM are readily ionized by the nitrogen laser. In this study, hydrophobic NOMs (HPO NOMs) from river, reservoir and waste water were characterized by this technique. The effect of analytical variables like concentration, solvent composition and laser energy was investigated. The exact masses of small molecular NOM moieties in the range of 200-1200 m/z were determined in reflectron mode. In addition, spectra of post-source-decay experiments in this range showed that some compounds from different natural NOMs had the same fragmental ions. In the large mass range of 1200-15 000 Da, macromolecules and their aggregates were found in HPO NOMs from natural waters. Highly humic HPO exhibited mass peaks larger than 8000 Da. On the other hand, the waste water and reservoir water mainly had relatively smaller molecules of about 2000 Da. The LDI-MS measurements indicated that highly humic river waters were able to form large aggregates and membrane foulants, while the HPO NOMs from waste water and reservoir water were unlikely to form large aggregates. Copyright © 2014 John Wiley \& Sons, Ltd.}, language = {en} } @article{WhiteheadOehlschlaegerAlmajhdietal.2014, author = {Whitehead, Mark and {\"O}hlschl{\"a}ger, Peter and Almajhdi, Fahad N. and Alloza, Leonor and Marz{\´a}bal, Pablo and Meyers, Ann E. and Hitzeroth, Inga I. and Rybicki, Edward P.}, title = {Human papillomavirus (HPV) type 16 E7 protein bodies cause tumour regression in mice}, series = {BMC cancer}, journal = {BMC cancer}, number = {14:367}, publisher = {BioMed Central}, address = {London}, issn = {1471-2407}, doi = {10.1186/1471-2407-14-367}, pages = {1 -- 15}, year = {2014}, language = {en} } @article{WiesenTippkoetterMuffleretal.2014, author = {Wiesen, Sebastian and Tippk{\"o}tter, Nils and Muffler, Kai and Suck, Kirstin and Sohling, Ulrich and Ruf, Nils and Ulber, Roland}, title = {Adsorptive Vorbehandlung von Rohglycerin f{\"u}r die 1,3-Propandiol Fermentation mit Clostridium diolis}, series = {Chemie Ingenieur Technik}, volume = {86}, journal = {Chemie Ingenieur Technik}, number = {1-2}, publisher = {Wiley-VCH}, address = {Weinheim}, doi = {10.1002/cite.201300080}, pages = {129 -- 135}, year = {2014}, abstract = {Bei der Gewinnung von Fetts{\"a}uren aus Pflanzen{\"o}len, z. B. zur Herstellung von Biopolymeren, oder bei der Biodiesel- und Seifenproduktion, f{\"a}llt Glycerin als Nebenprodukt an. Bei der Biokonversion dieses Rohstoffes zu 1,3-Propandiol wird der Produktionsorganismus Clostridium diolis durch Verunreinigungen im Rohglycerin gehemmt. Als inhibierende Substanzen konnten freie Fetts{\"a}uren identifiziert werden. Mithilfe eines adsorptiven Aufarbeitungsverfahrens ist es gelungen, die Fetts{\"a}uren zu entfernen und die Konversionseffizienz zu 1,3-Propandiol zu erh{\"o}hen.}, language = {de} } @article{WincklerKruegerSchnitzleretal.2014, author = {Winckler, Silvia and Krueger, Rolf and Schnitzler, Thomas and Zang, Werner and Fischer, Rainer and Biselli, Manfred}, title = {A sensitive monitoring system for mammalian cell cultivation processes: a PAT approach}, series = {Bioprocess and biosystems engineering}, volume = {37}, journal = {Bioprocess and biosystems engineering}, number = {5}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {1615-7591 (Print) 1615-7605 (Online)}, doi = {10.1007/s00449-013-1062-8}, pages = {901 -- 912}, year = {2014}, abstract = {Biopharmaceuticals such as antibodies are produced in cultivated mammalian cells, which must be monitored to comply with good manufacturing practice. We, therefore, developed a fully automated system comprising a specific exhaust gas analyzer, inline analytics and a corresponding algorithm to precisely determine the oxygen uptake rate, carbon dioxide evolution rate, carbon dioxide transfer rate, transfer quotient and respiratory quotient without interrupting the ongoing cultivation, in order to assess its reproducibility. The system was verified using chemical simulation experiments and was able to measure the respiratory activity of hybridoma cells and DG44 cells (derived from Chinese hamster ovary cells) with satisfactory results at a minimum viable cell density of ~2.0 × 10⁵ cells ml⁻¹. The system was suitable for both batch and fed-batch cultivations in bubble-aerated and membrane-aerated reactors, with and without the control of pH and dissolved oxygen.}, language = {en} }