@article{PasteurTippkoetterKampeisetal.2014, author = {Pasteur, Aline and Tippk{\"o}tter, Nils and Kampeis, Percy and Ulber, Roland}, title = {Optimization of high gradient magnetic separation filter units for the purification of fermentation products}, series = {IEEE TRANSACTIONS ON MAGNETICS}, volume = {50}, journal = {IEEE TRANSACTIONS ON MAGNETICS}, number = {10}, publisher = {IEEE}, address = {New York, NY}, issn = {0018-9464}, doi = {10.1109/TMAG.2014.2325535}, pages = {Artikel 5000607}, year = {2014}, abstract = {High gradient magnetic separation (HGMS) has been established since the early 1970s. A more recent application of these systems is the use in bioprocesses. To integrate the HGMS in a fermentation process, it is necessary to optimize the separation matrix with regard to the magnetic separation characteristics and permeability of the non-magnetizable components of the fermentation broth. As part of the work presented here, a combined fluidic and magnetic force finite element model simulation was created using the software COMSOL Multiphysics and compared with separation experiments. Finally, as optimal lattice orientation of the separation matrix, a transversal rhombohedral arrangement was defined. The high suitability of the new filter matrix has been verified by separation experiments.}, language = {en} } @article{UlberTippkoetter2009, author = {Ulber, Roland and Tippk{\"o}tter, Nils}, title = {Nitratfreie Molke}, series = {Rundschau f{\"u}r Fleischhygiene und Lebensmittel{\"u}berwachung}, journal = {Rundschau f{\"u}r Fleischhygiene und Lebensmittel{\"u}berwachung}, number = {4}, pages = {150 -- 152}, year = {2009}, language = {de} } @misc{AlKaidyTippkoetterUlber2013, author = {Al-Kaidy, Huschyar and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {A system and a method for the implementation of chemical, biological or physical reactions [Europ{\"a}ische Patentanmeldung]}, publisher = {Europ{\"a}isches Patentamt}, address = {Den Hague}, pages = {16 Seiten}, year = {2013}, abstract = {The invention relates to a system for the implementation of chemical, biological or physical reactions, consisting of - one or more magnetic micro-reactors, each comprising a shell made of hydrophobic magnetic nanoparticles encapsulating an aqueous core, - a plane platform comprising a surface to receive the micro-reactors, - a source that generates a magnetic field above or underneath the platform for manipulating the one or more hydrophobic magnetic micro-reactors, or for moving them along the surface of the platform from one position to another position, characterized in that the aqueous core of the one or more magnetic micro-reactors contains a reaction solution or buffer, and wherein the magnetic field generated by the source correlates to a defined position on the surface of the platform.}, language = {en} } @article{WiesenTippkoetterMuffleretal.2015, author = {Wiesen, Sebastian and Tippk{\"o}tter, Nils and Muffler, Kai and Suck, Kirstin and Sohling, Ulrich and Ruf, Friedrich and Ulber, Roland}, title = {Adsorption of fatty acids to layered double hydroxides in aqueous systems}, series = {Adsorption}, volume = {21}, journal = {Adsorption}, number = {6-7}, publisher = {Springer}, address = {Berlin}, pages = {459 -- 466}, year = {2015}, abstract = {Due to their anion exchange characteristics, layered double hydroxides (LDHs) are suitable for the detoxification of aqueous, fatty acid containing fermentation substrates. The aim of this study is to examine the adsorption mechanism, using crude glycerol from plant oil esterification as a model system. Changes in the intercalation structure in relation to the amount of fatty acids adsorbed are monitored by X-ray diffraction and infra-red spectroscopy. Additionally, calcination of LDH is investigated in order to increase the binding capacity for fatty acids. Our data propose that, at ambient temperature, fatty acids can be bound to the hydrotalcite by adsorption or in addition by intercalation, depending on fatty acid concentration. The adsorption of fatty acids from crude glycerol shows a BET-like behavior. Above a fatty acid concentration of 3.5 g L-1, intercalation of fatty acids can be shown by the appearance of an increased interlayer spacing. This observation suggests a two phase adsorption process. Calcination of LDHs allows increasing the binding capacity for fatty acids by more than six times, mainly by reduction of structural CO32-.}, language = {en} } @article{MuesgenanntKoersPrevostPaulssenetal.2023, author = {Mues genannt Koers, Lucas and Prevost, David and Paulßen, Elisabeth and Hoehr, Cornelia}, title = {Density reduction effects on the production of [11C]CO2 in Nb-body targets on a medical cyclotron}, volume = {199}, number = {Art. 110911}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.apradiso.2023.110911}, year = {2023}, abstract = {Medical isotope production of 11C is commonly performed in gaseous targets. The power deposition of the proton beam during the irradiation decreases the target density due to thermodynamic mixing and can cause an increase of penetration depth and divergence of the proton beam. In order to investigate the difference how the target-body length influences the operation conditions and the production yield, a 12 cm and a 22 cm Nb-target body containing N2/O2 gas were irradiated using a 13 MeV proton cyclotron. It was found that the density reduction has a large influence on the pressure rise during irradiation and the achievable radioactive yield. The saturation activity of [11C]CO2 for the long target (0.083 Ci/μA) is about 10\% higher than in the short target geometry (0.075 Ci/μA).}, language = {en} } @article{BergsMonakhovaDiehletal.2021, author = {Bergs, Michel and Monakhova, Yulia and Diehl, Bernd W. and Konow, Christopher and V{\"o}lkering, Georg and Pude, Ralf and Schulze, Margit}, title = {Lignins isolated via catalyst-free organosolv pulping from Miscanthus x giganteus, M. sinensis, M. robustus and M. nagara: a comparative study}, series = {Molecules}, volume = {26}, journal = {Molecules}, number = {4}, publisher = {MDPI}, address = {Basel}, issn = {1420-3049}, doi = {10.3390/molecules26040842}, year = {2021}, abstract = {As a low-input crop, Miscanthus offers numerous advantages that, in addition to agricultural applications, permits its exploitation for energy, fuel, and material production. Depending on the Miscanthus genotype, season, and harvest time as well as plant component (leaf versus stem), correlations between structure and properties of the corresponding isolated lignins differ. Here, a comparative study is presented between lignins isolated from M. x giganteus, M. sinensis, M. robustus and M. nagara using a catalyst-free organosolv pulping process. The lignins from different plant constituents are also compared regarding their similarities and differences regarding monolignol ratio and important linkages. Results showed that the plant genotype has the weakest influence on monolignol content and interunit linkages. In contrast, structural differences are more significant among lignins of different harvest time and/or season. Analyses were performed using fast and simple methods such as nuclear magnetic resonance (NMR) spectroscopy. Data was assigned to four different linkages (A: β-O-4 linkage, B: phenylcoumaran, C: resinol, D: β-unsaturated ester). In conclusion, A content is particularly high in leaf-derived lignins at just under 70\% and significantly lower in stem and mixture lignins at around 60\% and almost 65\%. The second most common linkage pattern is D in all isolated lignins, the proportion of which is also strongly dependent on the crop portion. Both stem and mixture lignins, have a relatively high share of approximately 20\% or more (maximum is M. sinensis Sin2 with over 30\%). In the leaf-derived lignins, the proportions are significantly lower on average. Stem samples should be chosen if the highest possible lignin content is desired, specifically from the M. x giganteus genotype, which revealed lignin contents up to 27\%. Due to the better frost resistance and higher stem stability, M. nagara offers some advantages compared to M. x giganteus. Miscanthus crops are shown to be very attractive lignocellulose feedstock (LCF) for second generation biorefineries and lignin generation in Europe.}, language = {en} } @article{BurgerRumpfDoetal.2021, author = {Burger, Ren{\´e} and Rumpf, Jessica and Do, Xuan Tung and Monakhova, Yulia and Diehl, Bernd W. K. and Rehahn, Matthias and Schulze, Margit}, title = {Is NMR combined with multivariate regression applicable for the molecular weight determination of randomly cross-linked polymers such as lignin?}, series = {ACS Omega}, volume = {6}, journal = {ACS Omega}, number = {44}, publisher = {ACS Publications}, address = {Washington, DC}, issn = {2470-1343}, doi = {10.1021/acsomega.1c03574}, pages = {29516 -- 29524}, year = {2021}, abstract = {The molecular weight properties of lignins are one of the key elements that need to be analyzed for a successful industrial application of these promising biopolymers. In this study, the use of 1H NMR as well as diffusion-ordered spectroscopy (DOSY NMR), combined with multivariate regression methods, was investigated for the determination of the molecular weight (Mw and Mn) and the polydispersity of organosolv lignins (n = 53, Miscanthus x giganteus, Paulownia tomentosa, and Silphium perfoliatum). The suitability of the models was demonstrated by cross validation (CV) as well as by an independent validation set of samples from different biomass origins (beech wood and wheat straw). CV errors of ca. 7-9 and 14-16\% were achieved for all parameters with the models from the 1H NMR spectra and the DOSY NMR data, respectively. The prediction errors for the validation samples were in a similar range for the partial least squares model from the 1H NMR data and for a multiple linear regression using the DOSY NMR data. The results indicate the usefulness of NMR measurements combined with multivariate regression methods as a potential alternative to more time-consuming methods such as gel permeation chromatography.}, language = {en} } @article{MonakhovaDiehl2022, author = {Monakhova, Yulia and Diehl, Bernd W.K.}, title = {Nuclear magnetic resonance spectroscopy as an elegant tool for a complete quality control of crude heparin material}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {219}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 114915}, publisher = {Elsevier}, address = {New York, NY}, issn = {0731-7085}, doi = {10.1016/j.jpba.2022.114915}, year = {2022}, abstract = {Nuclear magnetic resonance (NMR) spectrometric methods for the quantitative analysis of pure heparin in crude heparin is proposed. For quantification, a two-step routine was developed using a USP heparin reference sample for calibration and benzoic acid as an internal standard. The method was successfully validated for its accuracy, reproducibility, and precision. The methodology was used to analyze 20 authentic porcine heparinoid samples having heparin content between 4.25 w/w \% and 64.4 w/w \%. The characterization of crude heparin products was further extended to a simultaneous analysis of these common ions: sodium, calcium, acetate and chloride. A significant, linear dependence was found between anticoagulant activity and assayed heparin content for thirteen heparinoids samples, for which reference data were available. A Diffused-ordered NMR experiment (DOSY) can be used for qualitative analysis of specific glycosaminoglycans (GAGs) in heparinoid matrices and, potentially, for quantitative prediction of molecular weight of GAGs. NMR spectrometry therefore represents a unique analytical method suitable for the simultaneous quantitative control of organic and inorganic composition of crude heparin samples (especially heparin content) as well as an estimation of other physical and quality parameters (molecular weight, animal origin and activity).}, language = {en} } @article{MonakhovaDiehl2021, author = {Monakhova, Yulia and Diehl, Bernd W. K.}, title = {Simplification of NMR Workflows by Standardization Using 2H Integral of Deuterated Solvent as Applied to Aloe vera Preparations}, series = {Applied Magnetic Resonance}, volume = {52}, journal = {Applied Magnetic Resonance}, number = {11}, publisher = {Springer}, address = {Cham}, issn = {1613-7507}, doi = {10.1007/s00723-021-01393-4}, pages = {1591 -- 1600}, year = {2021}, abstract = {In this study, a recently proposed NMR standardization approach by 2H integral of deuterated solvent for quantitative multicomponent analysis of complex mixtures is presented. As a proof of principle, the existing NMR routine for the analysis of Aloe vera products was modified. Instead of using absolute integrals of targeted compounds and internal standard (nicotinamide) from 1H-NMR spectra, quantification was performed based on the ratio of a particular 1H-NMR compound integral and 2H-NMR signal of deuterated solvent D2O. Validation characteristics (linearity, repeatability, accuracy) were evaluated and the results showed that the method has the same precision as internal standardization in case of multicomponent screening. Moreover, a dehydration process by freeze drying is not necessary for the new routine. Now, our NMR profiling of A. vera products needs only limited sample preparation and data processing. The new standardization methodology provides an appealing alternative for multicomponent NMR screening. In general, this novel approach, using standardization by 2H integral, benefits from reduced sample preparation steps and uncertainties, and is recommended in different application areas (purity determination, forensics, pharmaceutical analysis, etc.).}, language = {en} } @article{BurgerLindnerRumpfetal.2022, author = {Burger, Ren{\´e} and Lindner, Simon and Rumpf, Jessica and Do, Xuan Tung and Diehl, Bernd W.K. and Rehahn, Matthias and Monakhova, Yulia and Schulze, Margit}, title = {Benchtop versus high field NMR: Comparable performance found for the molecular weight determination of lignin}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {212}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 114649}, publisher = {Elsevier}, address = {New York, NY}, isbn = {0731-7085}, doi = {10.1016/j.jpba.2022.114649}, year = {2022}, abstract = {Lignin is a promising renewable biopolymer being investigated worldwide as an environmentally benign substitute of fossil-based aromatic compounds, e.g. for the use as an excipient with antioxidant and antimicrobial properties in drug delivery or even as active compound. For its successful implementation into process streams, a quick, easy, and reliable method is needed for its molecular weight determination. Here we present a method using 1H spectra of benchtop as well as conventional NMR systems in combination with multivariate data analysis, to determine lignin's molecular weight (Mw and Mn) and polydispersity index (PDI). A set of 36 organosolv lignin samples (from Miscanthus x giganteus, Paulownia tomentosa and Silphium perfoliatum) was used for the calibration and cross validation, and 17 samples were used as external validation set. Validation errors between 5.6\% and 12.9\% were achieved for all parameters on all NMR devices (43, 60, 500 and 600 MHz). Surprisingly, no significant difference in the performance of the benchtop and high-field devices was found. This facilitates the application of this method for determining lignin's molecular weight in an industrial environment because of the low maintenance expenditure, small footprint, ruggedness, and low cost of permanent magnet benchtop NMR systems.}, language = {en} } @article{MonakhovaSobolevaFedotovaetal.2022, author = {Monakhova, Yulia and Soboleva, Polina M. and Fedotova, Elena S. and Musina, Kristina T. and Burmistrova, Natalia A.}, title = {Quantum chemical calculations of IR spectra of heparin disaccharide subunits}, series = {Computational and Theoretical Chemistry}, volume = {1217}, journal = {Computational and Theoretical Chemistry}, number = {Article number: 113891}, publisher = {Elsevier}, address = {New York, NY}, isbn = {2210-271X}, doi = {10.1016/j.comptc.2022.113891}, year = {2022}, abstract = {Heparin is a natural polysaccharide, which plays essential role in many biological processes. Alterations in building blocks can modify biological roles of commercial heparin products, due to significant changes in the conformation of the polymer chain. The variability structure of heparin leads to difficulty in quality control using different analytical methods, including infrared (IR) spectroscopy. In this paper molecular modelling of heparin disaccharide subunits was performed using quantum chemistry. The structural and spectral parameters of these disaccharides have been calculated using RHF/6-311G. In addition, over-sulphated chondroitin sulphate disaccharide was studied as one of the most widespread contaminants of heparin. Calculated IR spectra were analyzed with respect to specific structure parameters. IR spectroscopic fingerprint was found to be sensitive to substitution pattern of disaccharide subunits. Vibrational assignments of calculated spectra were correlated with experimental IR spectral bands of native heparin. Chemometrics was used to perform multivariate analysis of simulated spectral data.}, language = {en} } @article{BurmistrovaSobolevaMonakhova2021, author = {Burmistrova, Natalia A. and Soboleva, Polina M. and Monakhova, Yulia}, title = {Is infrared spectroscopy combined with multivariate analysis a promising tool for heparin authentication?}, series = {Journal of Pharmaceutical and Biomedical Analysis}, volume = {194}, journal = {Journal of Pharmaceutical and Biomedical Analysis}, number = {Article number: 113811}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {0731-7085}, doi = {10.1016/j.jpba.2020.113811}, year = {2021}, abstract = {The investigation of the possibility to determine various characteristics of powder heparin (n = 115) was carried out with infrared spectroscopy. The evaluation of heparin samples included several parameters such as purity grade, distributing company, animal source as well as heparin species (i.e. Na-heparin, Ca-heparin, and heparinoids). Multivariate analysis using principal component analysis (PCA), soft independent modelling of class analogy (SIMCA), and partial least squares - discriminant analysis (PLS-DA) were applied for the modelling of spectral data. Different pre-processing methods were applied to IR spectral data; multiplicative scatter correction (MSC) was chosen as the most relevant. Obtained results were confirmed by nuclear magnetic resonance (NMR) spectroscopy. Good predictive ability of this approach demonstrates the potential of IR spectroscopy and chemometrics for screening of heparin quality. This approach, however, is designed as a screening tool and is not considered as a replacement for either of the methods required by USP and FDA.}, language = {en} } @inproceedings{PothMonzonTippkoetteretal.2010, author = {Poth, Sebastian and Monzon, Magaly and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Lignocellulosic biorefinery : process integration of hydrolysis and fermentation}, series = {Proceedings / 11th European Workshop on Lignocellulosics and Pulp : August 16 - 19, 2010, Hamburg, Germany}, booktitle = {Proceedings / 11th European Workshop on Lignocellulosics and Pulp : August 16 - 19, 2010, Hamburg, Germany}, publisher = {vTi}, address = {Hamburg}, pages = {65 -- 68}, year = {2010}, language = {en} } @article{LuisierLempiaeinenScherbichleretal.2014, author = {Luisier, Rapha{\"e}lle and Lempi{\"a}inen, Harri and Scherbichler, Nina and Braeuning, Albert and Geissler, Miriam and Dubost, Valerie and M{\"u}ller, Arne and Scheer, Nico and Chibout, Salah-Dine and Hara, Hisanori and Picard, Frank and Theil, Diethilde and Couttet, Philippe and Vitobello, Antonio and Grenet, Olivier and Grasl-Kraupp, Bettina and Ellinger-Ziegelbauer, Heidrung and Thomson, John P. and Meehan, Richard R. and Elcombe, Clifford R. and Henderson, Colin J. and Wolf, C. Roland and Schwarz, Michael and Moulin, Pierre and Terranova, Remi and Moggs, Jonathan G.}, title = {Phenobarbital Induces Cell Cycle Transcriptional Responses in Mouse Liver Humanized for Constitutive Androstane and Pregnane X Receptors}, series = {Toxicological Sciences}, volume = {139}, journal = {Toxicological Sciences}, number = {2}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1094-2025}, doi = {https://doi.org/10.1093/toxsci/kfu038}, pages = {501 -- 511}, year = {2014}, abstract = {The constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) are closely related nuclear receptors involved in drug metabolism and play important roles in the mechanism of phenobarbital (PB)-induced rodent nongenotoxic hepatocarcinogenesis. Here, we have used a humanized CAR/PXR mouse model to examine potential species differences in receptor-dependent mechanisms underlying liver tissue molecular responses to PB. Early and late transcriptomic responses to sustained PB exposure were investigated in liver tissue from double knock-out CAR and PXR (CARᴷᴼ-PXRᴷᴼ), double humanized CAR and PXR (CARʰ-PXRʰ), and wild-type C57BL/6 mice. Wild-type and CARʰ-PXRʰ mouse livers exhibited temporally and quantitatively similar transcriptional responses during 91 days of PB exposure including the sustained induction of the xenobiotic response gene Cyp2b10, the Wnt signaling inhibitor Wisp1, and noncoding RNA biomarkers from the Dlk1-Dio3 locus. Transient induction of DNA replication (Hells, Mcm6, and Esco2) and mitotic genes (Ccnb2, Cdc20, and Cdk1) and the proliferation-related nuclear antigen Mki67 were observed with peak expression occurring between 1 and 7 days PB exposure. All these transcriptional responses were absent in CARᴷᴼ-PXRᴷᴼ mouse livers and largely reversible in wild-type and CARʰ-PXRʰ mouse livers following 91 days of PB exposure and a subsequent 4-week recovery period. Furthermore, PB-mediated upregulation of the noncoding RNA Meg3, which has recently been associated with cellular pluripotency, exhibited a similar dose response and perivenous hepatocyte-specific localization in both wild-type and CARʰ-PXRʰ mice. Thus, mouse livers coexpressing human CAR and PXR support both the xenobiotic metabolizing and the proliferative transcriptional responses following exposure to PB.}, language = {en} } @article{ScheerMclaughlinRodeetal.2014, author = {Scheer, Nico and Mclaughlin, Lesley A. and Rode, Anja and MacLeod, Alastair Kenneth and Henderson, Colin J. and Wolf, Roland C.}, title = {Deletion of thirty murine cytochrome P450 genes results in viable mice with compromised drug metabolism}, series = {Drug Metabolism and Disposition}, volume = {42}, journal = {Drug Metabolism and Disposition}, number = {6}, publisher = {ASPET}, address = {Bethesda, Md.}, issn = {1521-009X}, doi = {10.1124/dmd.114.057885}, pages = {1022 -- 1030}, year = {2014}, abstract = {In humans, 75\% of all drugs are metabolized by the cytochrome P450-dependent monooxygenase system. Enzymes encoded by the CYP2C, CYP2D, and CYP3A gene clusters account for ∼80\% of this activity. There are profound species differences in the multiplicity of cytochrome P450 enzymes, and the use of mouse models to predict pathways of drug metabolism is further complicated by overlapping substrate specificity between enzymes from different gene families. To establish the role of the hepatic and extrahepatic P450 system in drug and foreign chemical disposition, drug efficacy, and toxicity, we created a unique mouse model in which 30 cytochrome P450 genes from the Cyp2c, Cyp2d, and Cyp3a gene clusters have been deleted. Remarkably, despite a wide range of putative important endogenous functions, Cyp2c/2d/3a KO mice were viable and fertile, demonstrating that these genes have evolved primarily as detoxification enzymes. Although there was no overt phenotype, detailed examination showed Cyp2c/2d/3a KO mice had a smaller body size (15\%) and larger livers (20\%). Changes in hepatic morphology and a decreased blood glucose (30\%) were also noted. A five-drug cocktail of cytochrome P450 isozyme probe substrates were used to evaluate changes in drug pharmacokinetics; marked changes were observed in either the pharmacokinetics or metabolites formed from Cyp2c, Cyp2d, and Cyp3a substrates, whereas the metabolism of the Cyp1a substrate caffeine was unchanged. Thus, Cyp2c/2d/3a KO mice provide a powerful model to study the in vivo role of the P450 system in drug metabolism and efficacy, as well as in chemical toxicity.}, language = {en} } @article{ScheerHendersonKapelyukhetal.2019, author = {Scheer, Nico and Henderson, Colin James and Kapelyukh, Yury and Rode, Anja and Mclaren, Aileen W. and MacLeod, Alastair Kenneth and Lin, De and Wright, Jayne and Stanley, Lesley and Wolf, C. Roland}, title = {An extensively humanised mouse model to predict pathways of drug disposition, drug/drug interactions, and to facilitate the design of clinical trials}, series = {Drug Metabolism and Disposition}, journal = {Drug Metabolism and Disposition}, number = {Early view}, doi = {10.1124/dmd.119.086397}, pages = {69 Seiten}, year = {2019}, language = {en} } @phdthesis{Berndt1972, author = {Berndt, Heinz}, title = {Zur Synthese der Sequenz 60-84[Ala71, Gly72, Val73] des Schweineproinsulins als monomeres cyclisches Bis-Cystinpeptidderivat}, address = {Aachen}, pages = {115 S.}, year = {1972}, language = {de} } @misc{BerndtHoeckerKuropkaetal.1991, author = {Berndt, Heinz and H{\"o}cker, Hartwig and Kuropka, Rolf and Kinkel, Joachim}, title = {Silane coated inorganic materials for chromatography : United States Patent}, publisher = {[The United States Patent and Trademark Office]}, address = {[Alexandria, VA u.a.]}, pages = {9 S. : graph. Darst.}, year = {1991}, language = {en} } @article{WilsonWilsonScheeretal.2017, author = {Wilson, Ian D. and Wilson, Claire E. and Scheer, Nico and Dickie, A.P. and Schreiter, K. and Wilson, E. M. and Riley, R. J. and Wehr, R. and Bial, J.}, title = {The Pharmacokinetics and Metabolism of Lumiracoxib in Chimeric Humanized and Murinized FRG Mice}, series = {Biochemical pharmacology}, volume = {Volume 135}, journal = {Biochemical pharmacology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2968}, doi = {10.1016/j.bcp.2017.03.015}, pages = {139 -- 150}, year = {2017}, language = {en} } @article{HoughNalwalkDingetal.2015, author = {Hough, Lindsay B. and Nalwalk, Julia W. and Ding, Xinxin and Scheer, Nico}, title = {Opioid Analgesia in P450 Gene Cluster Knockout Mice: A Search for Analgesia-Relevant Isoforms}, series = {Drug Metabolism and Disposition}, volume = {43}, journal = {Drug Metabolism and Disposition}, number = {9}, issn = {1521-009x}, doi = {10.1124/dmd.115.065490}, pages = {1326 -- 1330}, year = {2015}, language = {en} } @article{MuesgenanntKoersMcNeilRadchenkoetal.2023, author = {Mues genannt Koers, Lucas and McNeil, S. W. and Radchenko, V. and Paulßen, Elisabeth and Hoehr, Cornelia}, title = {Production of Co-58m in a siphon-style liquid target on a medical cyclotron}, volume = {195}, number = {Art. 110734}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0969-8043}, doi = {10.1016/j.apradiso.2023.110734}, year = {2023}, abstract = {We present the production of 58mCo on a small, 13 MeV medical cyclotron utilizing a siphon style liquid target system. Different concentrated iron(III)-nitrate solutions of natural isotopic distribution were irradiated at varying initial pressures and subsequently separated by solid phase extraction chromatography. The radio cobalt (58m/gCo and 56Co) was successfully produced with saturation activities of (0.35 ± 0.03) MBq μA-1 for 58mCo with a separation recovery of (75 ± 2) \% of cobalt after one separation step utilizing LN-resin.}, language = {en} } @article{BerndtZahn1975, author = {Berndt, Heinz and Zahn, Helmut}, title = {Peptide, 99 : Monomere cyclische Cystinpeptidderivate, III ; Synthese der Schafinsulin-A-Kettensequenzen A2-21 und A1-21 als monomere cyclische Dicystinpeptidderivate}, series = {Justus Liebigs Annalen der Chemie}, volume = {1975}, journal = {Justus Liebigs Annalen der Chemie}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1099-0690}, doi = {10.1002/jlac.197519750908}, pages = {1601 -- 1612}, year = {1975}, abstract = {Die Synthese der Sequenzen A2—21 (13) und A1—21 (15) der Schafinsulin-A-Kette als monomere cyclische Dicystinpeptidderivate wird beschrieben. Die intrachenaren Cystinbr{\"u}cken A6—7 und A 11 —20 vermitteln die L{\"o}slichkeit dieser Derivate in Dimethylformamid und erm{\"o}glichen erstmalig die Reindarstellung vollgesch{\"u}tzter Insulin-A-Kettenderivate. Die w{\"a}hrend der Synthese eingesetzten Schutzgruppen lassen sich mittels Trifluoressigs{\"a}ure und 2-Mercapto{\"a}thanol quantitativ entfernen.}, language = {de} } @article{MangRoosenAnsorgeetal.2006, author = {Mang, Thomas and Roosen, C. and Ansorge, Marion and Leitner, W.}, title = {Gaining pH-control in water/carbon dioxide biphasic systems / Abstract No. 1038 / Roosen, Ch. ; Ansorge, M. ; Mang, Thomas ; Leitner, W. ; Greiner, L.}, series = {Green solvents for processes : Lake Constance, Friedrichshafen, Germany, 8 - 11 October 2006 ; book of abstracts / DECHEMA e.V.}, journal = {Green solvents for processes : Lake Constance, Friedrichshafen, Germany, 8 - 11 October 2006 ; book of abstracts / DECHEMA e.V.}, publisher = {DECHEMA}, address = {Frankfurt am Main}, pages = {145 S.}, year = {2006}, language = {en} } @article{ZientzBongaertsUnden1998, author = {Zientz, Evelyn and Bongaerts, Johannes and Unden, Gottfried}, title = {Fumarate regulation of gene expression in Escherichia coli by the DcuSR (dcuSR genes) two-component regulatory system}, series = {Journal of bacteriology}, volume = {Vol. 180}, journal = {Journal of bacteriology}, number = {No. 20}, issn = {1098-5530 (E-Journal); 0021-9193 (Print)}, pages = {5421 -- 5425}, year = {1998}, language = {en} } @inproceedings{DeterdingTippkoetterUlber2006, author = {Deterding, A. and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Online-Essigs{\"a}ureanalytik in Fermentationsbr{\"u}hen mittels Fließdiffusionstechnik (FDT)}, series = {Technische Systeme f{\"u}r Biotechnologie und Umwelt : 13. Heiligenst{\"a}dter Kolloquium, Heilbad Heiligenstadt, 25.09. - 27.09.2006}, booktitle = {Technische Systeme f{\"u}r Biotechnologie und Umwelt : 13. Heiligenst{\"a}dter Kolloquium, Heilbad Heiligenstadt, 25.09. - 27.09.2006}, editor = {Beckmann, Dieter}, address = {Heiligenstadt}, organization = {Institut f{\"u}r Bioprozeß- und Analysenmeßtechnik}, isbn = {978-3-00-018621-9}, pages = {273 -- 280}, year = {2006}, language = {de} } @incollection{UlberMufflerTippkoetteretal.2011, author = {Ulber, Roland and Muffler, Kai and Tippk{\"o}tter, Nils and Hirth, Thomas and Sell, Dieter}, title = {Introduction to Renewable Resources in the Chemical Industry}, series = {Renewable raw materials : new feedstocks for the chemical industry}, booktitle = {Renewable raw materials : new feedstocks for the chemical industry}, editor = {Ulber, Roland and Sell, Dieter and Hirth, Thomas}, edition = {1. Auflage}, publisher = {Wiley-VCH-Verlag}, address = {Weinheim}, isbn = {978-3-527-32548-1}, pages = {1 -- 6}, year = {2011}, language = {de} } @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{RothTippkoetter2016, author = {Roth, Jasmine and Tippk{\"o}tter, Nils}, title = {Evaluation of lignocellulosic material for butanol production using enzymatic hydrolysate medium}, series = {Cellulose Chemistry and Technology}, volume = {50}, journal = {Cellulose Chemistry and Technology}, number = {3-4}, publisher = {Editura Academiei Romane}, address = {Bukarest}, pages = {405 -- 410}, year = {2016}, abstract = {Butanol is a promising gasoline additive and platform chemical that can be readily produced via acetone-butanolethanol (ABE) fermentation from pretreated lignocellulosic materials. This article examines lignocellulosic material from beech wood for ABE fermentation, using Clostridium acetobutylicum. First, the utilization of both C₅₋ (xylose) and C₆₋ (glucose) sugars as sole carbon source was investigated in static cultivation, using serum bottles and synthetic medium. The utilization of pentose sugar resulted in a solvent yield of 0.231 g·g_sugar⁻¹, compared to 0.262 g·g_sugar⁻¹ using hexose. Then, the Organosolv pretreated crude cellulose fibers (CF) were enzymatically decomposed, and the resulting hydrolysate medium was analyzed for inhibiting compounds (furans, organic acids, phenolics) and treated with ionexchangers for detoxification. Batch fermentation in a bioreactor using CF hydrolysate medium resulted in a total solvent yield of 0.20 gABE·g_sugar⁻¹.}, language = {en} } @article{BechtSchollmayerMonakhovaetal.2021, author = {Becht, Alexander and Schollmayer, Curd and Monakhova, Yulia and Holzgrabe, Ulrike}, title = {Tracing the origin of paracetamol tablets by near-infrared, mid-infrared, and nuclear magnetic resonance spectroscopy using principal component analysis and linear discriminant analysis}, series = {Analytical and Bioanalytical Chemistry}, volume = {413}, journal = {Analytical and Bioanalytical Chemistry}, publisher = {Springer Nature}, issn = {1618-2650}, doi = {10.1007/s00216-021-03249-z}, pages = {3107 -- 3118}, year = {2021}, abstract = {Most drugs are no longer produced in their own countries by the pharmaceutical companies, but by contract manufacturers or at manufacturing sites in countries that can produce more cheaply. This not only makes it difficult to trace them back but also leaves room for criminal organizations to fake them unnoticed. For these reasons, it is becoming increasingly difficult to determine the exact origin of drugs. The goal of this work was to investigate how exactly this is possible by using different spectroscopic methods like nuclear magnetic resonance and near- and mid-infrared spectroscopy in combination with multivariate data analysis. As an example, 56 out of 64 different paracetamol preparations, collected from 19 countries around the world, were chosen to investigate whether it is possible to determine the pharmaceutical company, manufacturing site, or country of origin. By means of suitable pre-processing of the spectra and the different information contained in each method, principal component analysis was able to evaluate manufacturing relationships between individual companies and to differentiate between production sites or formulations. Linear discriminant analysis showed different results depending on the spectral method and purpose. For all spectroscopic methods, it was found that the classification of the preparations to their manufacturer achieves better results than the classification to their pharmaceutical company. The best results were obtained with nuclear magnetic resonance and near-infrared data, with 94.6\%/99.6\% and 98.7/100\% of the spectra of the preparations correctly assigned to their pharmaceutical company or manufacturer.}, language = {en} } @article{LindnerBurgerRutledgeetal.2022, author = {Lindner, Simon and Burger, Ren{\´e} and Rutledge, Douglas N. and Do, Xuan Tung and Rumpf, Jessica and Diehl, Bernd W. K. and Schulze, Margit and Monakhova, Yulia}, title = {Is the calibration transfer of multivariate calibration models between high- and low-field NMR instruments possible? A case study of lignin molecular weight}, series = {Analytical chemistry}, volume = {94}, journal = {Analytical chemistry}, number = {9}, publisher = {ACS Publications}, address = {Washington, DC}, isbn = {1520-6882}, doi = {10.1021/acs.analchem.1c05125}, pages = {3997 -- 4004}, year = {2022}, abstract = {Although several successful applications of benchtop nuclear magnetic resonance (NMR) spectroscopy in quantitative mixture analysis exist, the possibility of calibration transfer remains mostly unexplored, especially between high- and low-field NMR. This study investigates for the first time the calibration transfer of partial least squares regressions [weight average molecular weight (Mw) of lignin] between high-field (600 MHz) NMR and benchtop NMR devices (43 and 60 MHz). For the transfer, piecewise direct standardization, calibration transfer based on canonical correlation analysis, and transfer via the extreme learning machine auto-encoder method are employed. Despite the immense resolution difference between high-field and low-field NMR instruments, the results demonstrate that the calibration transfer from high- to low-field is feasible in the case of a physical property, namely, the molecular weight, achieving validation errors close to the original calibration (down to only 1.2 times higher root mean square errors). These results introduce new perspectives for applications of benchtop NMR, in which existing calibrations from expensive high-field instruments can be transferred to cheaper benchtop instruments to economize.}, language = {en} } @article{AboulnagaPinkenburgSchiffelsetal.2013, author = {Aboulnaga, El-Hussiny and Pinkenburg, Olaf and Schiffels, Johannes and El-Refai, Ahmed and Buckel, Wolfgang and Selmer, Thorsten}, title = {Butyrate production in Escherichia coli: Exploitation of an oxygen tolerant bifurcating butyryl-CoA dehydrogenase/electron transferring flavoprotein complex from Clostridium difficile}, series = {Journal of bacteriology. June 14, 2013}, journal = {Journal of bacteriology. June 14, 2013}, issn = {1098-5530 (E-Journal) ; 0021-9193 (Print)}, pages = {Epub ahead of print}, year = {2013}, language = {de} } @article{AboulnagaZouSelmeretal.2018, author = {Aboulnaga, Elhussiny A. and Zou, Huibin and Selmer, Thorsten and Xian, Mo}, title = {Development of a plasmid-based, tunable, tolC-derived expression system for application in Cupriavidus necator H16}, series = {Journal of Biotechnology}, volume = {274}, journal = {Journal of Biotechnology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0168-1656}, doi = {10.1016/j.jbiotec.2018.03.007}, pages = {15 -- 27}, year = {2018}, abstract = {Cupriavidus necator H16 gains increasing attention in microbial research and biotechnological application due to its diverse metabolic features. Here we present a tightly controlled gene expression system for C. necator including the pBBR1-vector that contains hybrid promoters originating from C. necator native tolC-promoter in combination with a synthetic tetO-operator. The expression of the reporter gene from these plasmids relies on the addition of the exogenous inducer doxycycline (dc). The novel expression system offers a combination of advantageous features as; (i) high and dose-dependent recombinant protein production, (ii) tight control with a high dynamic range (On/Off ratio), which makes it applicable for harmful pathways or for toxic protein production, (iii) comparable cheap inducer (doxycycline, dc), (iv) effective at low inducer concentration, that makes it useful for large scale application, (v) rapid, diffusion controlled induction, and (vi) the inducer does not interfere within the cell metabolism. As applications of the expression system in C. necator H16, the growth ability on glycerol was enhanced by constitutively expressing the E. coli glpk gene-encoding for glycerol kinase. Likewise, we used the system to overcome the expression toxicity of mevalonate pathway in C. necator H16. With this system, the mevalonate-genes were successfully introduced in the host and the recombinant strains could produce about 200 mg/l mevalonate.}, language = {en} } @article{BerndtGattnerZahn1975, author = {Berndt, Heinz and Gattner, Hans-Gregor and Zahn, Helmut}, title = {Semisynthetisches Des-A1-glycin-Schafinsulin}, series = {Biological Chemistry}, volume = {356}, journal = {Biological Chemistry}, number = {2}, publisher = {De Gruyter}, address = {Berlin}, issn = {1437-4315}, doi = {10.1515/bchm2.1975.356.2.1455}, pages = {1469 -- 1472}, year = {1975}, language = {de} } @article{GielenWolfBerndtetal.1979, author = {Gielen, Hans-G{\"u}nther and Wolf, G{\"u}nter and Berndt, Heinz and Zahn, Helmut}, title = {Synthese der Fragmente A1-8, A9-15 und A16-21 der Schafinsulin-A-Kette unter Verwendung des S-tert-Butylmercaptorestes als Thiolschutzgruppe}, series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, volume = {360}, journal = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, number = {2}, issn = {1437-4315}, doi = {10.1515/bchm2.1979.360.2.1535}, pages = {1535 -- 1548}, year = {1979}, language = {de} } @article{WolfBerndtBrandenburg1979, author = {Wolf, Wilhelm and Berndt, Heinz and Brandenburg, Dietrich}, title = {Synthese von Fragmenten einer [LysA13] Rinder-Insulin-A-Kette unter Verwendung des S-tert-Butylmercaptorestes als Thiolschutz}, series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, volume = {360}, journal = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, number = {2}, issn = {1437-4315}, doi = {10.1515/bchm2.1979.360.2.1549}, pages = {1549 -- 1558}, year = {1979}, language = {de} } @article{WilhelmBerndtBrandenburg1979, author = {Wilhelm, Wolff and Berndt, Heinz and Brandenburg, Dietrich}, title = {Zur Synthese der H{\"u}hnerinsulin-A-Kette, I : Darstellung der Fragmente A1-8, A9-15, A1-7 und A8-15}, series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, volume = {360}, journal = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, number = {2}, issn = {1437-4315}, doi = {10.1515/bchm2.1979.360.2.1559}, pages = {1559 -- 1568}, year = {1979}, language = {de} } @article{Berndt1979, author = {Berndt, Heinz}, title = {Synthese der Sequenz 71—86 des Humanproinsulins, III : Synthese {\"u}ber die Fragmente 71—78 und 79—86}, series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, volume = {360}, journal = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, number = {1}, issn = {1437-4315}, doi = {10.1515/bchm2.1979.360.1.765}, pages = {765 -- 772}, year = {1979}, language = {de} } @inproceedings{ZahnBerndtFehrenbach1973, author = {Zahn, Helmut and Berndt, Heinz and Fehrenbach, P.}, title = {Synthese cyclischer Cystinpeptide mit Insulin A-und B-Kettensequenzen}, series = {Peptides 1972 : proceedings of the Twelfth European Peptide Symposium, Reinhardsbrunn Castle, German Democratic Republic, September 1972}, booktitle = {Peptides 1972 : proceedings of the Twelfth European Peptide Symposium, Reinhardsbrunn Castle, German Democratic Republic, September 1972}, editor = {Hanson, Horst}, publisher = {North-Holland Publ. [u.a.],}, address = {Amsterdam [u.a.]}, isbn = {0-7204-4132-3}, pages = {101 -- 102}, year = {1973}, language = {de} } @inproceedings{KalbeKuropkaMeyerStorketal.1988, author = {Kalbe, Jochen and Kuropka, Rolf and Meyer-Stork, L. Sebastian and Lauter, S. L. and H{\"o}cker, Hartwig and Berndt, Heinz}, title = {Identification of fine animal hair via DNA analysis}, series = {Proceedings of the 1st International Symposium on Specialty Animal Fibers : Aachen, October 26 - 27, 1987 ; [scientific, technological and economical aspects] . - (Schriftenreihe des Deutschen Wollforschungsinstitutes an der Technischen Hochschule Aachen e.V. ; 103)}, booktitle = {Proceedings of the 1st International Symposium on Specialty Animal Fibers : Aachen, October 26 - 27, 1987 ; [scientific, technological and economical aspects] . - (Schriftenreihe des Deutschen Wollforschungsinstitutes an der Technischen Hochschule Aachen e.V. ; 103)}, editor = {K{\"o}rner, Andrea}, publisher = {Dt. Wollforschungsinst.}, address = {Aachen}, issn = {0930-3723}, pages = {221 -- 227}, year = {1988}, language = {en} } @article{KruegerGroetzingerBerndt1987, author = {Kr{\"u}ger, G{\"o}tz and Gr{\"o}tzinger, Joachim and Berndt, Heinz}, title = {Enantiomeric resolution of amino acid derivatives on chiral stationary phases by high-performance liquid chromatography}, series = {Journal of Chromatography A}, volume = {1987}, journal = {Journal of Chromatography A}, number = {397}, issn = {0021-9673}, doi = {10.1016/S0021-9673(01)85005-6}, pages = {223 -- 232}, year = {1987}, 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} } @misc{BerndtHoeckerKuropkaetal.1990, author = {Berndt, Heinz and H{\"o}cker, Hartwig and Kuropka, Rolf and Kinkel, Joachim}, title = {Silanderivate : Europ{\"a}ische Patenschrift / Offenlegungsschrift}, publisher = {Europ{\"a}isches Patentamt / Deutsches Patent- und Markenamt}, address = {Den Hague / M{\"u}nchen}, pages = {10 S. / 13 S. : graph. Darst.}, year = {1990}, language = {de} } @article{NokiharaBerndt1978, author = {Nokihara, Kiyoshi and Berndt, Heinz}, title = {Synthesis of hapten-polypeptide conjugates as antigen models for the N-terminal region of the α-2-chain of rabbit skin collagen}, series = {Journal of the Royal Society of Chemistry: Perkin Transactions 1}, volume = {1978}, journal = {Journal of the Royal Society of Chemistry: Perkin Transactions 1}, number = {3}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {1364-5463}, doi = {10.1039/P19780000260}, pages = {260 -- 263}, year = {1978}, abstract = {Synthesis of derivatives of the peptide sequence L-pyroglutamyl-L-phenylalanyl-L-aspartyl-glycyl-L-lysyl-glycyl-glycyl-glycine as the antigenic determinant representing the N-terminal non-helical region of the α-2-chain of rabbit skin collagen, and conjugation to two different polypeptide carriers, are described.}, language = {en} } @inproceedings{KroggelBerndt1984, author = {Kroggel, Matthias and Berndt, Heinz}, title = {The 0-hydroxiphenyloxicarbonyl-group a new base labile amine protecting group}, series = {Peptides 1984 : Proceedings of the 18th European Peptide Symposium Djur{\"o}n{\"a}set, Sweden, June 10 - 15, 1984}, booktitle = {Peptides 1984 : Proceedings of the 18th European Peptide Symposium Djur{\"o}n{\"a}set, Sweden, June 10 - 15, 1984}, editor = {Ragnarsson, Ulf}, publisher = {Almquist \& Wiksell}, address = {Stockholm}, isbn = {91-22-00715-6}, pages = {81 -- 83}, year = {1984}, language = {en} } @article{ScheerKapelyukhRodeetal.2012, author = {Scheer, Nico and Kapelyukh, Yury and Rode, Anja and Buechel, Sandra and Wolf, C. Roland}, title = {Generation and characterization of novel cytochrome P450 Cyp2c gene cluster knockout and CYP2C9 humanized mouse lines}, series = {Molecular Pharmacology}, volume = {82}, journal = {Molecular Pharmacology}, number = {6}, publisher = {ASPET}, address = {Bethesda, Md.}, issn = {1521-0111}, doi = {10.1124/mol.112.080036}, pages = {1022 -- 1029}, year = {2012}, abstract = {Compared with rodents and many other animal species, the human cytochrome P450 (P450) Cyp2c gene cluster varies significantly in the multiplicity of functional genes and in the substrate specificity of its enzymes. As a consequence, the use of wild-type animal models to predict the role of human CYP2C enzymes in drug metabolism and drug-drug interactions is limited. Within the human CYP2C cluster CYP2C9 is of particular importance, because it is one of the most abundant P450 enzymes in human liver, and it is involved in the metabolism of a wide variety of important drugs and environmental chemicals. To investigate the in vivo functions of cytochrome P450 Cyp2c genes and to establish a model for studying the functions of CYP2C9 in vivo, we have generated a mouse model with a deletion of the murine Cyp2c gene cluster and a corresponding humanized model expressing CYP2C9 specifically in the liver. Despite the high number of functional genes in the mouse Cyp2c cluster and the reported roles of some of these proteins in different biological processes, mice deleted for Cyp2c genes were viable and fertile but showed certain phenotypic alterations in the liver. The expression of CYP2C9 in the liver also resulted in viable animals active in the metabolism and disposition of a number of CYP2C9 substrates. These mouse lines provide a powerful tool for studying the role of Cyp2c genes and of CYP2C9 in particular in drug disposition and as a factor in drug-drug interaction.}, language = {en} } @article{Berndt1980, author = {Berndt, Heinz}, title = {Zur Reaktion von Iminodithiocarbonaten mit Carbons{\"a}uren. I : Synthese des Modellpeptid-Derivates Z-(L)-Ala-(L/D)-Phe-(L)-Val-OMe}, series = {Tetrahedron letters}, volume = {21}, journal = {Tetrahedron letters}, number = {34}, issn = {0040-4039}, doi = {10.1016/S0040-4039(00)78663-1}, pages = {3265 -- 3268}, year = {1980}, language = {de} } @article{BerndtKrueger1985, author = {Berndt, Heinz and Kr{\"u}ger, G{\"o}tz}, title = {Resolution of enantiomeric amino acid derivatives by high-performance liquid chromatography on chiral stationary phases}, series = {Journal of chromatography A}, volume = {1985}, journal = {Journal of chromatography A}, number = {348}, issn = {0021-9673}, doi = {10.1016/S0021-9673(01)92461-6}, pages = {275 -- 279}, year = {1985}, language = {en} } @inproceedings{SiekerDuwePothetal.2012, author = {Sieker, T. and Duwe, A. and Poth, S. and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Herstellung von Itacons{\"a}ure aus Buchenholzhydrolysaten}, series = {Kurzfassungsband / GVC-DECHEMA Vortrags- und Diskussionstagung Biopharmazeutische Produktion : 14. - 16. Mai 2012. Konzerthaus Freibung}, booktitle = {Kurzfassungsband / GVC-DECHEMA Vortrags- und Diskussionstagung Biopharmazeutische Produktion : 14. - 16. Mai 2012. Konzerthaus Freibung}, publisher = {DECHEMA}, address = {Frankfurt, M.}, pages = {57}, year = {2012}, language = {de} } @article{MeyerStorkKalbeKuropkaetal.1988, author = {Meyer-Stork, L. Sebastian and Kalbe, Jochen and Kuropka, Rolf and Sauter, S. L. and H{\"o}cker, Hartwig and Berndt, Heinz}, title = {Eindeutige Provenienzanalyse von Wolle und feinen Tierhaaren mit Hilfe der Erbsubstanz (DNS)}, series = {Textilveredlung : schweizerische Zeitschrift f{\"u}r Textilchemie, Textilveredlung und deren Randgebiete}, volume = {23}, journal = {Textilveredlung : schweizerische Zeitschrift f{\"u}r Textilchemie, Textilveredlung und deren Randgebiete}, number = {9}, issn = {0040-5310}, pages = {304 -- 307}, year = {1988}, language = {de} } @article{SchnabelSchnabelBerndt1971, author = {Schnabel, Eugen and Schnabel, Henning and Berndt, Heinz}, title = {Zur selektiven acidolytischen Abspaltbarkeit der tert.-Butyloxycarbonyl-Gruppe}, series = {Justus Liebigs Annalen der Chemie}, volume = {749}, journal = {Justus Liebigs Annalen der Chemie}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1099-0690}, doi = {10.1002/jlac.19717490111}, pages = {90 -- 108}, year = {1971}, abstract = {Die tert.-Butyloxycarbonyl-Gruppe (Boc) l{\"a}ßt sich mittels reiner Trifluoressigs{\"a}ure nicht selektiv neben dem Benzyloxycarbonyl-Rest (Z) abspalten. Das gelingt auch nicht mit L{\"o}sungen von Trifluoressigs{\"a}ure bzw. Chlorwasserstoff in organischen L{\"o}sungsmitteln. Kern-substituierte Z-Gruppen wie Z(pCl), Z(mCl) oder Z(pNO₂) sind zwar stabiler, werden aber von den obengenannten Reagenzien ebenfalls angegriffen bzw. sind nicht mehr acidolytisch abspaltbar. - Mit 70proz. w{\"a}ßriger Trifluoressigs{\"a}ure gelingt die Abspaltung von Boc neben Z dagegen fast selektiv; dabei werden aber Benzylester, besonders Glutamins{\"a}ure-γ-benzylester, teilweise hydrolysiert, w{\"a}hrend Methyl- sowie {\"A}thylester nahezu best{\"a}ndig sind. Die Brauchbarkeit des Abspaltungsverfahrens wird anhand der schrittweise durchgef{\"u}hrten Synthese zweier Heptapeptid-Derivate gezeigt. - {\"A}hnlich spezifisch gelingt die Abspaltung von Boc mit Bortrifluorid-{\"a}therat in Eisessig; Benzylester sind gegen{\"u}ber diesem Reagenz stabiler als gegen w{\"a}ßrige Trifluoressigs{\"a}ure. Das Bortrifluorid-Verfahren eignet sich besonders f{\"u}r die Abspaltung von Boc-Gruppen neben s{\"a}urelabilen Thiol-Schutzgruppen (Tetrahydropyranyl- bzw. Trityl-Rest) sowie neben dem Cyclocystinyl-Rest. Die Leistungsf{\"a}higkeit der Methode wird durch die Synthese zweier Peptid-Derivate mit S-Trityl-Schutzgruppen belegt. Als Nebenreaktion ist die Acetylierung von aliphatischen Hydroxylgruppen m{\"o}glich. Sie l{\"a}ßt sich vermeiden, wenn man die Spaltung in anderen L{\"o}sungsmitteln durchf{\"u}hrt. Die als Modellverbindungen f{\"u}r Stabilit{\"a}tsuntersuchungen verwendeten Nε-acylierten Lysin-Derivate werden mit dem Aminos{\"a}ureanalysator quantitativ neben Lysin bestimmt.}, language = {de} } @article{KuropkaMuellerHoeckeretal.1989, author = {Kuropka, Rolf and M{\"u}ller, Bettina and H{\"o}cker, Hartwig and Berndt, Heinz}, title = {Chiral stationary phases via hydrosilylation reaction of N-acryloylamino acids : I. Stationary phase with one chiral centre for high-performance liquid chromatography and development of a new derivatization pattern for amino acid enantiomers}, series = {Journal of chromatography A}, journal = {Journal of chromatography A}, number = {481}, isbn = {0021-9673}, pages = {380 -- 386}, year = {1989}, language = {en} } @article{NokiharaBerndt1978, author = {Nokihara, Kiyoshi and Berndt, Heinz}, title = {Studies on sulfur-containing peptides : tert-butyloxycarbonylsulfenyl and benzyloxycarbonylsulfenyl derivatives as protecting groups for cysteine}, series = {The journal of organic chemistry}, volume = {43}, journal = {The journal of organic chemistry}, number = {25}, publisher = {American Chemical Society}, address = {Washington}, issn = {0022-3263}, doi = {10.1021/jo00419a046}, pages = {4893 -- 4895}, year = {1978}, language = {en} } @article{KalbeHoeckerBerndt1989, author = {Kalbe, Jochen and H{\"o}cker, Hartwig and Berndt, Heinz}, title = {Design of enzyme reactors as chromatographic columns for racemic resolution of amino acid esters}, series = {Chromatographia}, volume = {28}, journal = {Chromatographia}, number = {3-4}, isbn = {0009-5893}, doi = {10.1007/BF02319646}, pages = {193 -- 196}, year = {1989}, language = {en} } @article{TurckBerndt1981, author = {Turck, Christoph W. and Berndt, Heinz}, title = {Synthese definierter Peptid-Derivate durch Aminolyse von 3-(Nα-Acyl-peptidyloxy)-2-hydroxy-N-alkylbenzamiden bei erh{\"o}hten Temperaturen, I : Synthese des Modellpeptid-Derivates Z-Ala-Phe-Gly-N(Et)2}, series = {Hoppe-Seyler´s Zeitschrift f{\"u}r physiologische Chemie}, volume = {362}, journal = {Hoppe-Seyler´s Zeitschrift f{\"u}r physiologische Chemie}, number = {1}, issn = {1437-4315}, doi = {10.1515/bchm2.1981.362.1.821}, pages = {821 -- 828}, year = {1981}, language = {de} } @article{DanhoNaithaniSasakietal.1980, author = {Danho, Waleed and Naithani, Vinod K. and Sasaki, Andr{\´e} N. and F{\"o}hles, Joseph and Berndt, Heinz and B{\"u}llesbach, Erika E. and Zahn, H.}, title = {Human proinsulin, VII : synthesis of two protected peptides corresponding to the sequences 1—45 and 46—86 of the prohormone}, series = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, volume = {361}, journal = {Hoppe-Seyler's Zeitschrift f{\"u}r physiologische Chemie}, number = {1}, issn = {1437-4315}, doi = {10.1515/bchm2.1980.361.1.857}, pages = {857 -- 863}, year = {1980}, language = {en} } @article{KalbeKuropkaMeyerStorketal.1988, author = {Kalbe, Jochen and Kuropka, Rolf and Meyer-Stork, L. Sebastian and Berndt, Heinz and Sauter, Sybille L. and Loss, Peter and Hendo, Karsten and Riesner, Detlev and H{\"o}cker, Hartwig}, title = {Isolation and characterization of high-molecular mass DNA from hair shafts}, series = {Biological chemistry}, volume = {369}, journal = {Biological chemistry}, number = {1}, isbn = {0177-3593}, doi = {10.1515/bchm3.1988.369.1.413}, pages = {413 -- 416}, year = {1988}, language = {en} } @article{BaumannTillmannAletsee1989, author = {Baumann, Marcus and Tillmann, Urban and Aletsee, Ludwig}, title = {Distribution of Carbon Among Photosynthetic End Products in the Bloom-Forming Arctic Diatom Thalassiosira antarctica COMBER / Tillmann, U. ; Baumann, M.E.M. ; Aletsee, L.}, series = {Polar Biology. 10 (1989), H. 3}, journal = {Polar Biology. 10 (1989), H. 3}, isbn = {0722-4060}, pages = {231 -- 238}, year = {1989}, language = {en} } @inproceedings{AlKaidyUlberTippkoetter2014, author = {Al-Kaidy, Huschyar and Ulber, Roland and Tippk{\"o}tter, Nils}, title = {A platform technology for the automated reaction control in magnetizable micro-fluidic droplets}, series = {Biomaterials - made in bioreactors : book of abstracts, May 26 - 28, 2014, Radisson Blu Park Hotel and Conference Dentre, Radebeul, Germany}, booktitle = {Biomaterials - made in bioreactors : book of abstracts, May 26 - 28, 2014, Radisson Blu Park Hotel and Conference Dentre, Radebeul, Germany}, publisher = {DECHEMA}, address = {Frankfurt am Main}, pages = {21 -- 22}, year = {2014}, language = {en} } @misc{KowollikSchnitzlerBisellietal.2010, author = {Kowollik, Silvia and Schnitzler, Thomas and Biselli, Manfred and Krueger, R. and Zang, Werner and Peuscher, A. and Schillberg, S. and Fischer, R.}, title = {Die Rolle des Respirationsquotienten in der Zellkulturfermentation}, series = {Chemie Ingenieur Technik}, volume = {82}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, isbn = {Chemie Ingenieur Tec}, doi = {10.1002/cite.201050393}, pages = {1505 -- 1506}, year = {2010}, abstract = {In der biopharmazeutischen Industrie werden rekombinante Proteine und monoklonale Antik{\"o}rper in Zellkulturfermentationen produziert, da nur humane oder tierische Zelllinien {\"u}ber die F{\"a}higkeit der Glykosylierung verf{\"u}gen. Um hohe Produktausbeuten in ausgezeichneter Qualit{\"a}t zu erzielen, ist eine funktionst{\"u}chtige Prozesskontrolle unerl{\"a}sslich. Hierzu wurde in Kooperation mit der Firma Hitec Zang GmbH die HiSense� Pr{\"a}zisionsabgasanalytik entwickelt, die auf Basis der vollautomatischen Ermittlung des Respirationsquotienten (RQ; Verh{\"a}ltnis vonKohlendioxidbildungsrate (CER) zu Sauerstoffaufnahmerate (OTR)) einen Fermentationsprozess nicht-invasiv {\"u}berwacht. Der RQ kann in Hybridoma- und CHO-Zellen (s. Abb.) in sowohl serumhaltigen als auch serumfreien Medien erfolgreich ermittelt werden. Hier spiegeln die CER und die OTR das Wachstumsverhalten der kultivierten CHO-Zellen wider. Der RQ nimmt dabei Werte zwischen 0,9 und 1,2 an. Dies l{\"a}sst auf verschiedene Stoffwechselaktivit{\"a}ten schließen. Da die momentane industrielle Prozesskontrolle auf gemessenen Sauerstoffaufnahmeraten oder entsprechende Offline-Analytiken der Metaboliten basieren, soll durch die vollautomatische RQ-Ermittlung ein neues Verfahren zur Fermentations{\"u}berwachung etabliert werden. Bisher war diese, in bakteriellen Kultivierungen standardisierte Methode, aufgrund der schwierigen CER-Berechnung bei Zellkulturen keine ad{\"a}quate Alternative.}, language = {de} } @article{RibitschHeumannKarletal.2012, author = {Ribitsch, Doris and Heumann, Sonja and Karl, Wolfgang and Gerlach, Jochen and Leber, Regina and Birner-Gruenberger, Ruth and Gruber, Karl and Eiteljoerg, Inge and Remler, Peter and Siegert, Petra and Lange, Jennifer and Maurer, Karl-Heinz and Berg, Gabriele and Guebitz, G. M. and Schwab, H.}, title = {Extracellular serine proteases from Stenotrophomonas maltophilia: Screening, isolation and heterologous expression in E. coli}, series = {Journal of biotechnology}, volume = {157}, journal = {Journal of biotechnology}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-4863 (E-Journal); 0168-1656 (Print)}, doi = {10.1016/j.jbiotec.2011.09.025}, pages = {140 -- 147}, year = {2012}, abstract = {A large strain collection comprising antagonistic bacteria was screened for novel detergent proteases. Several strains displayed protease activity on agar plates containing skim milk but were inactive in liquid media. Encapsulation of cells in alginate beads induced protease production. Stenotrophomonas maltophilia emerged as best performer under washing conditions. For identification of wash-active proteases, four extracellular serine proteases called StmPr1, StmPr2, StmPr3 and StmPr4 were cloned. StmPr2 and StmPr4 were sufficiently overexpressed in E. coli. Expression of StmPr1 and StmPr3 resulted in unprocessed, insoluble protein. Truncation of most of the C-terminal domain which has been identified by enzyme modeling succeeded in expression of soluble, active StmPr1 but failed in case of StmPr3. From laundry application tests StmPr2 turned out to be a highly wash-active protease at 45 °C. Specific activity of StmPr2 determined with suc-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide as the substrate was 17 ± 2 U/mg. In addition we determined the kinetic parameters and cleavage preferences of protease StmPr2.}, language = {en} } @article{SrivastavaSinghAggarwaletal.2010, author = {Srivastava, Alok and Singh, Virendra and Aggarwal, Pranav and Schneeweiss, F. and Scherer, Ulrich W. and Friedrich, W.}, title = {Optical studies of insulating polymers for radiation dose monitoring}, series = {Indian Journal of Pure and Applied Physics}, volume = {48}, journal = {Indian Journal of Pure and Applied Physics}, number = {11}, publisher = {Council Of Scientific And Industrial Research (CSIR), National Institute Of Science Communication and Policy Research (NIScPR)}, address = {New Delhi}, isbn = {0019-5596}, pages = {782 -- 786}, year = {2010}, abstract = {The optical study carried out on insulating polymers namely polyethyleneterephthalate (PET) and polyvinylchloride (PVC) has been described. The polymers are exposed to different radiation doses by exposing them to swift heavy ions of carbon (90 MeV), silicon (120 MeV) and nickel (100 MeV) which influence on their optical properties. The studies show that amongst the investigated polymers, PVC and PET have potential for application as dosimeter beyond a threshold dose which is strongly dependent on the nature of the material and the radiation type. The optical micrographs show a distinct change in colour of the sample with increase in radiation dose.}, language = {en} } @inproceedings{EngelThieringerTippkoetter2016, author = {Engel, Mareike and Thieringer, Julia and Tippk{\"o}tter, Nils}, title = {Linking bioprocess engineering and electrochemistry for sustainable biofuel production}, series = {Young Researchers Symposium, YRS 2016. Proceedings}, booktitle = {Young Researchers Symposium, YRS 2016. Proceedings}, publisher = {Fraunhofer Verlag}, address = {Karlsruhe}, pages = {49 -- 53}, year = {2016}, abstract = {Electromicrobial engineering is an emerging, highly interdisciplinary research area linking bioprocesses with electrochemistry. In this work, microbial electrosynthesis (MES) of biobutanol is carried out during acetone-butanol-ethanol (ABE) fermentations with Clostridium acetobutylicum. A constant electric potential of -600mV (vs. Ag/AgCl) with simultaneous addition of the soluble redox mediator neutral red is used in order to study the electron transfer between the working electrode and the bacterial cells. The results show an earlier initiation of solvent production for all fermentations with applied potential compared to the conventional ABE fermentation. The f inal butanol concentration can be more than doubled by the application of a negative potential combined with addition of neutral red. Moreover a higher biofilm formation on the working electrode compared to control cultivations has been observed. In contrast to previous studies, our results also indicate that direct electron transfer (DET) might be possible with C. acetobutylicum. The presented results make microbial butanol production economically attractive and therefore support the development of sustainable production processes in the chemical industry aspired by the "Centre for resource-efficient chemistry and raw material change" as well as the the project "NanoKat" working on nanostructured catalysts in Kaiserslautern.}, language = {en} } @article{OehlenschlaegerVolkmarStiefelmaieretal.2024, author = {Oehlenschl{\"a}ger, Katharina and Volkmar, Marianne and Stiefelmaier, Judith and Langsdorf, Alexander and Holtmann, Dirk and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {New insights into the influence of pre-culture on robust solvent production of C. acetobutylicum}, series = {Applied Microbiology and Biotechnology}, volume = {108}, journal = {Applied Microbiology and Biotechnology}, publisher = {Springer}, address = {Berlin, Heidelberg}, issn = {1432-0614}, doi = {10.1007/s00253-023-12981-8}, pages = {10 Seiten}, year = {2024}, abstract = {Clostridia are known for their solvent production, especially the production of butanol. Concerning the projected depletion of fossil fuels, this is of great interest. The cultivation of clostridia is known to be challenging, and it is difficult to achieve reproducible results and robust processes. However, existing publications usually concentrate on the cultivation conditions of the main culture. In this paper, the influence of cryo-conservation and pre-culture on growth and solvent production in the resulting main cultivation are examined. A protocol was developed that leads to reproducible cultivations of Clostridium acetobutylicum. Detailed investigation of the cell conservation in cryo-cultures ensured reliable cell growth in the pre-culture. Moreover, a reason for the acid crash in the main culture was found, based on the cultivation conditions of the pre-culture. The critical parameter to avoid the acid crash and accomplish the shift to the solventogenesis of clostridia is the metabolic phase in which the cells of the pre-culture were at the time of inoculation of the main culture; this depends on the cultivation time of the pre-culture. Using cells from the exponential growth phase to inoculate the main culture leads to an acid crash. To achieve the solventogenic phase with butanol production, the inoculum should consist of older cells which are in the stationary growth phase. Considering these parameters, which affect the entire cultivation process, reproducible results and reliable solvent production are ensured.}, language = {en} } @article{HengsbachEngelCwienczeketal.2023, author = {Hengsbach, Jan-Niklas and Engel, Mareike and Cwienczek, Marcel and Stiefelmaier, Judith and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Scalable unseparated bioelectrochemical reactors by using a carbon fiber brush as stirrer and working electrode}, series = {ChemElectroChem}, volume = {10}, journal = {ChemElectroChem}, number = {21}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {2196-0216}, doi = {10.1002/celc.202300440}, pages = {9 Seiten}, year = {2023}, abstract = {The concept of energy conversion into platform chemicals using bioelectrochemical systems (BES) has gained increasing attention in recent years, as the technology simultaneously provides an opportunity for sustainable chemical production and tackles the challenge of Power-to-X technologies. There are many approaches to realize the industrial scale of BES. One concept is to equip standard bioreactors with static electrodes. However, large installations resulted in a negative influence on various reactor parameters. In this study, we present a new single-chamber BES based on a stirred tank reactor in which the stirrer was replaced by a carbon fiber brush, performing the functions of the working electrode and the stirrer. The reactor is characterized in abiotic studies and electro-fermentations with Clostridium acetobutylicum. Compared to standard reactors an increase in butanol production of 20.14±3.66 \% shows that the new BES can be efficiently used for bioelectrochemical processes.}, language = {en} } @misc{DuweSchlegelTippkoetteretal.2014, author = {Duwe, A. and Schlegel, C. and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Sequentielle Extraktion von Cellulose zur effizienten Nutzung der Stoffstr{\"o}me in der Holzbioraffinerie}, series = {Chemie Ingenieur Technik}, volume = {86}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201450308}, pages = {1400}, year = {2014}, abstract = {In der Reihe der nachwachsenden Rohstoffe besitzt Holz als erneuerbare und umweltfreundliche Ressource ein großes Potenzial. {\"U}ber 11 Mio. ha Holz, das laut der Fachagentur f{\"u}r nachwachsende Rohstoffe (FNR) auch f{\"u}r industrielle Zwecke genutzt werden kann, wuchsen im Jahr 2013 allein auf bundesdeutscher Fl{\"a}che. 56,8 Mio. m³ j{\"a}hrlicher Holzeinschlag in den letzten zehn Jahren wurde zu knapp der H{\"a}lfte stofflich und der Rest energetisch verwertet. Im Rahmen dieser Arbeit konnte auf der Basis vom Holz der Buche, die nach Fichte und Kiefer die dritth{\"a}ufigste Baumart in Deutschland ist und 15\% der deutschen Waldfl{\"a}che ausmacht, die Fraktionierung der polymeren Hauptbestandteile mit niedrigem energetischen Einsatz erreicht werden. Hierbei werden in einem nachgeschalteten Extraktionsprozess die beiden Komponenten Hemicellulose und Lignin in fl{\"u}ssiger Form von der finalen festen Cellulosefraktion abgetrennt. Die Extraktion der Hemicellulose erfolgt durch eine Liquid Hot Water (LHW)-Behandlung. Untersucht wird der katalytische Zusatz anorganischer S{\"a}uren wie H₃PO₄ und H₂SO₄. Im Hinblick auf die weitere Verwertung von Lignin zu aromatischen Synthesebausteinen kommt die Organosolv-Extraktion mit einem Ethanol/Wasser-Gemisch zum Einsatz. Von Vorteil ist die weitere Verwendung beider Stoffstr{\"o}me ohne F{\"a}llungsschritt und nachteiliger Verd{\"u}nnung der Hemicellulose.}, language = {en} } @misc{MoehringWulfhorstCapitainetal.2016, author = {M{\"o}hring, S. and Wulfhorst, H. and Capitain, C. and Roth, J. and Tippk{\"o}tter, Nils}, title = {Fractioning of lignocellulosic biomass: Scale-down and automation of thermal pretreatment for parameter optimization}, series = {Chemie Ingenieur Technik}, volume = {88}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201650288}, pages = {1229}, year = {2016}, abstract = {In order to efficiently convert lignocellulose, it is often necessary to conduct a pretreatment. The biomass considered in this study typically comprises of agricultural and horticultural residues, as well as beechwood. A very environmentally friendly method, namely, fungal pretreatment using white-rot fungi, leads to an enhanced enzymatic hydrolysis. In contrast to other processes presented, the energy input is extremely low. However, the fungal growth on the lignocellulosic substrates takes several weeks at least in order to be effective. Thus, the reduction of chemicals and energy for thermal processing is a target of our current research. Liquid hot water (LHW) and solvent-based pretreatment (OrganoSolv) require more complex equipment, as they depend on high temperatures (160 - 180 °C) and enhanced pressure (up to 20 bar). However, they prove to be promising processes in regard to the fractioning of lignocellulose. For optimal lignin recovery the parameters differ from those established in cellulose extraction. A novel screening system scaled down to a reaction volume of 100 mL has been developed and successfully tested for this purpose.}, language = {en} } @article{WeldenSeverinsPoghossianetal.2022, author = {Welden, Melanie and Severins, Robin and Poghossian, Arshak and Wege, Christina and Bongaerts, Johannes and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Detection of acetoin and diacetyl by a tobacco mosaic virus-assisted field-effect biosensor}, series = {Chemosensors}, volume = {10}, journal = {Chemosensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2227-9040}, doi = {10.3390/chemosensors10060218}, pages = {Artikel 218}, year = {2022}, abstract = {Acetoin and diacetyl have a major impact on the flavor of alcoholic beverages such as wine or beer. Therefore, their measurement is important during the fermentation process. Until now, gas chromatographic techniques have typically been applied; however, these require expensive laboratory equipment and trained staff, and do not allow for online monitoring. In this work, a capacitive electrolyte-insulator-semiconductor sensor modified with tobacco mosaic virus (TMV) particles as enzyme nanocarriers for the detection of acetoin and diacetyl is presented. The enzyme acetoin reductase from Alkalihalobacillus clausii DSM 8716ᵀ is immobilized via biotin-streptavidin affinity, binding to the surface of the TMV particles. The TMV-assisted biosensor is electrochemically characterized by means of leakage-current, capacitance-voltage, and constant capacitance measurements. In this paper, the novel biosensor is studied regarding its sensitivity and long-term stability in buffer solution. Moreover, the TMV-assisted capacitive field-effect sensor is applied for the detection of diacetyl for the first time. The measurement of acetoin and diacetyl with the same sensor setup is demonstrated. Finally, the successive detection of acetoin and diacetyl in buffer and in diluted beer is studied by tuning the sensitivity of the biosensor using the pH value of the measurement solution.}, language = {en} } @article{WeldenJablonskiWegeetal.2021, author = {Welden, Rene and Jablonski, Melanie and Wege, Christina and Keusgen, Michael and Wagner, Patrick Hermann and Wagner, Torsten and Sch{\"o}ning, Michael Josef}, title = {Light-Addressable Actuator-Sensor Platform for Monitoring and Manipulation of pH Gradients in Microfluidics: A Case Study with the Enzyme Penicillinase}, series = {Biosensors}, volume = {11}, journal = {Biosensors}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios11060171}, pages = {Artikel 171}, year = {2021}, abstract = {The feasibility of light-addressed detection and manipulation of pH gradients inside an electrochemical microfluidic cell was studied. Local pH changes, induced by a light-addressable electrode (LAE), were detected using a light-addressable potentiometric sensor (LAPS) with different measurement modes representing an actuator-sensor system. Biosensor functionality was examined depending on locally induced pH gradients with the help of the model enzyme penicillinase, which had been immobilized in the microfluidic channel. The surface morphology of the LAE and enzyme-functionalized LAPS was studied by scanning electron microscopy. Furthermore, the penicillin sensitivity of the LAPS inside the microfluidic channel was determined with regard to the analyte's pH influence on the enzymatic reaction rate. In a final experiment, the LAE-controlled pH inhibition of the enzyme activity was monitored by the LAPS.}, language = {en} } @article{WeldenPoghossianVahidpouretal.2022, author = {Welden, Melanie and Poghossian, Arshak and Vahidpour, Farnoosh and Wendlandt, Tim and Keusgen, Michael and Wege, Christina and Sch{\"o}ning, Michael Josef}, title = {Towards multi-analyte detection with field-effect capacitors modified with tobacco mosaic virus bioparticles as enzyme nanocarriers}, series = {Biosensors}, volume = {12}, journal = {Biosensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {2079-6374}, doi = {10.3390/bios12010043}, pages = {Artikel 43}, year = {2022}, abstract = {Utilizing an appropriate enzyme immobilization strategy is crucial for designing enzyme-based biosensors. Plant virus-like particles represent ideal nanoscaffolds for an extremely dense and precise immobilization of enzymes, due to their regular shape, high surface-to-volume ratio and high density of surface binding sites. In the present work, tobacco mosaic virus (TMV) particles were applied for the co-immobilization of penicillinase and urease onto the gate surface of a field-effect electrolyte-insulator-semiconductor capacitor (EISCAP) with a p-Si-SiO₂-Ta₂O₅ layer structure for the sequential detection of penicillin and urea. The TMV-assisted bi-enzyme EISCAP biosensor exhibited a high urea and penicillin sensitivity of 54 and 85 mV/dec, respectively, in the concentration range of 0.1-3 mM. For comparison, the characteristics of single-enzyme EISCAP biosensors modified with TMV particles immobilized with either penicillinase or urease were also investigated. The surface morphology of the TMV-modified Ta₂O₅-gate was analyzed by scanning electron microscopy. Additionally, the bi-enzyme EISCAP was applied to mimic an XOR (Exclusive OR) enzyme logic gate.}, language = {en} } @article{ZhantlessovaSavitskayaKistaubayevaetal.2022, author = {Zhantlessova, Sirina and Savitskaya, Irina and Kistaubayeva, Aida and Ignatova, Ludmila and Talipova, Aizhan and Pogrebnjak, Alexander and Digel, Ilya}, title = {Advanced "Green" prebiotic composite of bacterial cellulose/pullulan based on synthetic biology-powered microbial coculture strategy}, series = {Polymers}, volume = {14}, journal = {Polymers}, number = {15}, publisher = {MDPI}, address = {Basel}, issn = {2073-4360}, doi = {10.3390/polym14153224}, pages = {Artikel 3224}, year = {2022}, abstract = {Bacterial cellulose (BC) is a biopolymer produced by different microorganisms, but in biotechnological practice, Komagataeibacter xylinus is used. The micro- and nanofibrillar structure of BC, which forms many different-sized pores, creates prerequisites for the introduction of other polymers into it, including those synthesized by other microorganisms. The study aims to develop a cocultivation system of BC and prebiotic producers to obtain BC-based composite material with prebiotic activity. In this study, pullulan (PUL) was found to stimulate the growth of the probiotic strain Lactobacillus rhamnosus GG better than the other microbial polysaccharides gellan and xanthan. BC/PUL biocomposite with prebiotic properties was obtained by cocultivation of Komagataeibacter xylinus and Aureobasidium pullulans, BC and PUL producers respectively, on molasses medium. The inclusion of PUL in BC is proved gravimetrically by scanning electron microscopy and by Fourier transformed infrared spectroscopy. Cocultivation demonstrated a composite effect on the aggregation and binding of BC fibers, which led to a significant improvement in mechanical properties. The developed approach for "grafting" of prebiotic activity on BC allows preparation of environmentally friendly composites of better quality.}, language = {en} } @article{HafidiElHatkaSchmitzetal.2024, author = {Hafidi, Youssef and El Hatka, Hicham and Schmitz, Dominik and Krauss, Manuel and Pettrak, J{\"u}rgen and Biel, Markus and Ittobane, Najim}, title = {Sustainable soil additives for water and micronutrient supply: swelling and chelating properties of polyaspartic acid hydrogels utilizing newly developed crosslinkers}, series = {Gels}, volume = {10}, journal = {Gels}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2310-2861}, doi = {10.3390/gels10030170}, pages = {Artikel 170}, year = {2024}, abstract = {Drought and water shortage are serious problems in many arid and semi-arid regions. This problem is getting worse and even continues in temperate climatic regions due to climate change. To address this problem, the use of biodegradable hydrogels is increasingly important for the application as water-retaining additives in soil. Furthermore, efficient (micro-)nutrient supply can be provided by the use of tailored hydrogels. Biodegradable polyaspartic acid (PASP) hydrogels with different available (1,6-hexamethylene diamine (HMD) and L-lysine (LYS)) and newly developed crosslinkers based on diesters of glycine (GLY) and (di-)ethylene glycol (DEG and EG, respectively) were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) and regarding their swelling properties (kinetic, absorbency under load (AUL)) as well as biodegradability of PASP hydrogel. Copper (II) and zinc (II), respectively, were loaded as micronutrients in two different approaches: in situ with crosslinking and subsequent loading of prepared hydrogels. The results showed successful syntheses of di-glycine-ester-based crosslinkers. Hydrogels with good water-absorbing properties were formed. Moreover, the developed crosslinking agents in combination with the specific reaction conditions resulted in higher water absorbency with increased crosslinker content used in synthesis (10\% vs. 20\%). The prepared hydrogels are candidates for water-storing soil additives due to the biodegradability of PASP, which is shown in an exemple. The incorporation of Cu(II) and Zn(II) ions can provide these micronutrients for plant growth.}, language = {en} } @article{ElBerguiAbouabdillahBouriougetal.2023, author = {El Bergui, Omnia and Abouabdillah, Aziz and Bourioug, Mohamed and Schmitz, Dominik and Biel, Markus and Aboudrare, Abdellah and Krauss, Manuel and Jomaa, Ahlem and Romuli, Sebastian and M{\"u}ller, Joachim and Fagroud, Mustapha and Bouabid, Rachid}, title = {Innovative solutions for drought: Evaluating hydrogel application on onion cultivation (Allium cepa) in Morocco}, series = {Water}, volume = {15}, journal = {Water}, number = {11}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/w15111972}, pages = {Artikel 1972}, year = {2023}, abstract = {Throughout the last decade, and particularly in 2022, water scarcity has become a critical concern in Morocco and other Mediterranean countries. The lack of rainfall during spring was worsened by a succession of heat waves during the summer. To address this drought, innovative solutions, including the use of new technologies such as hydrogels, will be essential to transform agriculture. This paper presents the findings of a study that evaluated the impact of hydrogel application on onion (Allium cepa) cultivation in Meknes, Morocco. The treatments investigated in this study comprised two different types of hydrogel-based soil additives (Arbovit® polyacrylate and Huminsorb® polyacrylate), applied at two rates (30 and 20 kg/ha), and irrigated at two levels of water supply (100\% and 50\% of daily crop evapotranspiration; ETc). Two control treatments were included, without hydrogel application and with both water amounts. The experiment was conducted in an open field using a completely randomized design. The results indicated a significant impact of both hydrogel-type dose and water dose on onion plant growth, as evidenced by various vegetation parameters. Among the hydrogels tested, Huminsorb® Polyacrylate produced the most favorable outcomes, with treatment T9 (100\%, HP, 30 kg/ha) yielding 70.55 t/ha; this represented an increase of 11 t/ha as compared to the 100\% ETc treatment without hydrogel application. Moreover, the combination of hydrogel application with 50\% ETc water stress showed promising results, with treatment T4 (HP, 30 kg, 50\%) producing almost the same yield as the 100\% ETc treatment without hydrogel while saving 208 mm of water.}, language = {en} } @techreport{BarnatArntzBerneckeretal.2024, type = {Working Paper}, author = {Barnat, Miriam and Arntz, Kristian and Bernecker, Andreas and Fissabre, Anke and Franken, Norbert and Goldbach, Daniel and H{\"u}ning, Felix and J{\"o}rissen, J{\"o}rg and Kirsch, Ansgar and Pettrak, J{\"u}rgen and Rexforth, Matthias and Josef, Rosenkranz and Terstegge, Andreas}, title = {Strategische Gestaltung von Studieng{\"a}ngen f{\"u}r die Zukunft: Ein kollaborativ entwickeltes Self-Assessment}, series = {Hochschulforum Digitalisierung - Diskussionspapier}, journal = {Hochschulforum Digitalisierung - Diskussionspapier}, publisher = {Stifterverband f{\"u}r die Deutsche Wissenschaft}, address = {Berlin}, issn = {2365-7081}, pages = {16 Seiten}, year = {2024}, abstract = {Das Diskussionspapier beschreibt einen Prozess an der FH Aachen zur Entwicklung und Implementierung eines Self-Assessment-Tools f{\"u}r Studieng{\"a}nge. Dieser Prozess zielte darauf ab, die Relevanz der Themen Digitalisierung, Internationalisierung und Nachhaltigkeit in Studieng{\"a}ngen zu st{\"a}rken. Durch Workshops und kollaborative Entwicklung mit Studiendekan:innen entstand ein Fragebogen, der zur Reflexion und strategischen Weiterentwicklung der Studieng{\"a}nge dient.}, language = {de} } @misc{RothTippkoetter2016, author = {Roth, J. and Tippk{\"o}tter, Nils}, title = {New Approach for Enzymatic Hydrolysis of Lignocellulose with Selective Diffusion Separation of the Monosaccharide Products}, series = {Chemie Ingenieur Technik}, volume = {88}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201650301}, pages = {1237}, year = {2016}, abstract = {Enzymatic hydrolysis of lignocellulosic material plays an important role in the classical biorefinery approach. Apart from the pretreatment of the raw material, hydrolysis is the basis for the conversion of the cellulose and hemicellulose fraction into fermentable sugars. After hydrolysis, usually a solid-liquid separation takes place, in order to separate the residual plant material from the sugar-rich fraction, which can be subsequently used in a fermentation step. In order to factor out the separation step, the usage of in alginate immobilized crude cellulose fiber beads (CFBs) were evaluated. Pretreated cellulose fibers are incorporated in an alginate matrix together with the relevant enzymes. In doing so, sugars diffuse trough the alginate matrix, allowing a simplified delivery into the surrounding fluid. This again reduces product inhibition of the glucose on the enzyme catalysts. By means of standardized bead production the hydrolysis in lab scale was possible. First results show that liberation of glucose and xylose is possible, allowing a maximum total sugar yield of 75 \%.}, language = {en} } @misc{TippkoetterUlber2012, author = {Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Rezension zu: Encyclopedia of Industrial Biotechnology, Vol. 1-7. By MC Flickinger.}, series = {Chemie Ingenieur Technik}, volume = {6}, journal = {Chemie Ingenieur Technik}, number = {84}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201290052}, pages = {936}, year = {2012}, language = {en} } @misc{TippkoetterWiesenThieletal.2014, author = {Tippk{\"o}tter, Nils and Wiesen, S. and Thiel, A. and Muffler, K. and Ulber, Roland}, title = {Biotechnologische Wertstoffgewinnung entlang der Prozessketten Gr{\"u}ner und Pflanzen{\"o}l-Bioraffinerien}, series = {Chemie Ingenieur Technik}, volume = {86}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201450283}, pages = {1605}, year = {2014}, abstract = {Der nachwachsende Rohstoff Raps ist in großen Mengen verf{\"u}gbar und eine Quelle f{\"u}r Biomolek{\"u}le mit hohem Wertsch{\"o}pfungspotenzial. Entwicklungen zur biotechnologischen Wertstoffgewinnung werden dabei schwerpunktm{\"a}ßig in den Bereichen Aufarbeitung und Funktionalisierung von Polyphenolen und Fetten betrieben. Bei der Verarbeitung der Pflanzenmaterialien werden dabei insbesondere Verfahren zur adsorptiven Aufreinigung und Auftrennung mittels Materialien mit modifizierten Bleicherden und anderen organischen oder anorganischen Adsorbentien untersucht. Ferner wurden f{\"u}r die Aufreinigung von Polyphenolen adsorptive sowie extraktive Prozesse entwickelt. Bei den Entwicklungen wird ber{\"u}cksichtigt, dass Bioraffinerien auf eine fortw{\"a}hrende Gew{\"a}hrleistung eines hohen Produktions- bzw. Lieferbedarfs nachwachsender Rohstoffe angewiesen sind. Somit werden Optionen dezentraler regionaler Vorbehandlungs- und Wertsch{\"o}pfungsketten in der N{\"a}he landwirtschaftlicher Betriebe einbezogen. Neben neuen Aufreinigungsverfahren werden mikrobielle und enzymatische Prozesse zur wertsteigernden Umsetzung von Glycerin, Polyphenolen und Zuckermonomeren vorgestellt sowie Limitierungen nachwachsender Rohstoffe der 2. Generation diskutiert.}, language = {de} } @article{FalkenbergBottBongaertsetal.2022, author = {Falkenberg, Fabian and Bott, Michael and Bongaerts, Johannes and Siegert, Petra}, title = {Phylogenetic survey of the subtilase family and a data-mining-based search for new subtilisins from Bacillaceae}, series = {Frontiers in Microbiology}, volume = {2022}, journal = {Frontiers in Microbiology}, number = {13}, publisher = {Frontiers}, address = {Lausanne}, issn = {1664-302X}, doi = {10.3389/fmicb.2022.1017978}, pages = {Artikel 13:1017978}, year = {2022}, abstract = {The subtilase family (S8), a member of the clan SB of serine proteases are ubiquitous in all kingdoms of life and fulfil different physiological functions. Subtilases are divided in several groups and especially subtilisins are of interest as they are used in various industrial sectors. Therefore, we searched for new subtilisin sequences of the family Bacillaceae using a data mining approach. The obtained 1,400 sequences were phylogenetically classified in the context of the subtilase family. This required an updated comprehensive overview of the different groups within this family. To fill this gap, we conducted a phylogenetic survey of the S8 family with characterised holotypes derived from the MEROPS database. The analysis revealed the presence of eight previously uncharacterised groups and 13 subgroups within the S8 family. The sequences that emerged from the data mining with the set filter parameters were mainly assigned to the subtilisin subgroups of true subtilisins, high-alkaline subtilisins, and phylogenetically intermediate subtilisins and represent an excellent source for new subtilisin candidates.}, language = {en} } @article{HaegerBongaertsSiegert2022, author = {Haeger, Gerrit and Bongaerts, Johannes and Siegert, Petra}, title = {A convenient ninhydrin assay in 96-well format for amino acid-releasing enzymes using an air-stable reagent}, series = {Analytical Biochemistry}, journal = {Analytical Biochemistry}, number = {624}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1096-0309}, doi = {10.1016/j.ab.2022.114819}, pages = {Artikel 114819}, year = {2022}, abstract = {An improved and convenient ninhydrin assay for aminoacylase activity measurements was developed using the commercial EZ Nin™ reagent. Alternative reagents from literature were also evaluated and compared. The addition of DMSO to the reagent enhanced the solubility of Ruhemann's purple (RP). Furthermore, we found that the use of a basic, aqueous buffer enhances stability of RP. An acidic protocol for the quantification of lysine was developed by addition of glacial acetic acid. The assay allows for parallel processing in a 96-well format with measurements microtiter plates.}, language = {en} } @misc{WollnyAlKaidyTippkoetteretal.2014, author = {Wollny, S. and Al-Kaidy, Huschyar and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Prozessintegrierte Magnetseparation im Labormaßstab mittels High-Gradient Magnetic Separator (HGMS)}, series = {Chemie Ingenieur Technik}, volume = {86}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201450618}, pages = {1507}, year = {2014}, abstract = {Die Hochgradient-Magnetseparation (HGMS) stellt eine Alternative zu konventionellen Methoden der Proteinaufarbeitung wie Filtration und Chromatographie dar und dient zudem als Prozessintensivierung. Bisherige Separatoren sind f{\"u}r Anwendungen von mehreren Litern Prozessvolumina Fermentationsmedium und Gramm Magnetpartikel ausgelegt. Bei der Entwicklung und Anwendung neuartiger Magnetpartikeloberfl{\"a}chen ist die Verf{\"u}gbarkeit großer Mengen nicht gegeben. Bisherige Filterkammern erh{\"o}hen zudem den Arbeitsaufwand und verursachen gr{\"o}ßere Partikelverluste bei Sp{\"u}lvorg{\"a}ngen oder der Reinigung aufgrund der Partikeladsorption. F{\"u}r Anwendungen im Maßstab < 500 mL wird deshalb ein Miniatur-Hochgradientfilter (miniHGF) entwickelt. Das Modell wird im 3D-Drucker Makerbot Replicator 2 gefertigt und magne-isierbare Dr{\"a}hte zur Partikelabscheidung eingesetzt. Die Vergleichbarkeit mit einem etablierten Magnetseparator wird anhand der Aufnahme von Durchbruchskurven und Bestimmung der Filtereffizienz untersucht. Die Praxistauglichkeit mit kleinen Volumina wird in wiederholten Batch-Versuchen mit auf Magnetpartikeln immobilisiertem Enzym und einem kolorimetrischen Assay gepr{\"u}ft.}, language = {de} } @misc{TippkoetterStaubSohlingetal.2012, author = {Tippk{\"o}tter, Nils and Staub, C. and Sohling, U. and Ruf, N. and Ulber, Roland}, title = {Adsorptive Aufreinigung von Molkeproteinen}, series = {Chemie Ingenieur Technik}, volume = {84}, journal = {Chemie Ingenieur Technik}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201250395}, pages = {1285}, year = {2012}, abstract = {In der Molkeverarbeitung dominieren Membranfiltrationsverfahren die Prozessf{\"u}hrung. Hierbei werden {\"u}blicherweise Aufkonzentrierungen der Proteine und deren Trennung von dem Milchzucker Lactose durchgef{\"u}hrt. Der Prozess der adsorptiven Aufreinigung soll als kosteng{\"u}nstige Alternative zu den bisher gebr{\"a}uchlichen Verfahren dienen. Weiterhin er{\"o}ffnet sich durch das Verfahren die M{\"o}glichkeit, einzelne Proteinfraktionen w{\"a}hrend der Verarbeitung anzureichern. Als Proteinquellen wurden f{\"u}r die Untersuchungen Modellproteine, L{\"o}sungen aus Molkenproteinisolat, D{\"u}nnmolke und Molkekonzentrat verwendet. Die Eignung zur Proteinbindung wurden an Tonmaterialien, Silicaten und y-Aluminiumoxiden in Pulverform, in Form von Granulaten sowie Extrudaten als auch sph{\"a}rischen Partikeln {\"u}berpr{\"u}ft. Adsorbentien aus Bentonit/Silica und c-Aluminiumoxid k{\"o}nnen sowohl a-Lactalbumin (aLA) als auch b-Lactoglobulin (bLG) binden, wohingegen Materialien aus Siliciumoxid lediglich ein starkes Adsorptionsverhalten gegen{\"u}ber bLG zeigen. Mischmaterialien aus Siliciumoxid und a-Aluminiumoxid zeigen dasselbe Verhalten wie Materialien aus Siliciumoxid, weisen jedoch eine geringere Kapazit{\"a}t auf. Die Materialen wurden hinsichtlich ihres Einsatzes in chromatographischen Verfahren und Batch-Prozessen untersucht und ein Prozessentwurf f{\"u}r einen zweistufigen Batch-Prozess im R{\"u}hrkessel erarbeitet.}, language = {de} } @misc{TippkoetterNeitmannSohlingetal.2009, author = {Tippk{\"o}tter, Nils and Neitmann, E. and Sohling, U. and Ruf, F. and Ulber, Roland}, title = {Anaerobe Produktion von ABE-L{\"o}sungsmitteln aus an Bleicherde adsorbiertem {\"O}l}, series = {Chemie Ingenieur Technik}, volume = {81}, journal = {Chemie Ingenieur Technik}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.200950075}, pages = {1217 -- 1218}, year = {2009}, abstract = {Mit Palm{\"o}l beladene Bleicherde wurde auf die Anwendbarkeit als Rohstoff zur Bildung von Aceton, Ethanol und Butanol (ABE) untersucht. Nach der Abtrennung des entf{\"a}rbten bzw. gebleichten {\"O}ls bestehen 20-40 \% (w/w) des Bleicherder{\"u}ckstands aus adsorbiertem {\"O}l. Somit stellt das Mineral einen wertvollen Rohstoff dar. Zur Produktion der L{\"o}sungsmittel wurde das gebundene {\"O}l hydrolysiert. Das freigesetzte Glycerin diente als Substrat einer nachfolgenden anaeroben Fermentation zu den ABE-L{\"o}sungsmitteln. Die Fermentationen wurden mit verschiedenen Clostridien-St{\"a}mmen durchgef{\"u}hrt, von denen einige lipolytische Aktivit{\"a}t aufweisen. Der {\"O}lgehalt der Bleicherde betrug 28 \% der Adsorbermasse. F{\"u}r die Hydrolyse wurden drei Ans{\"a}tze untersucht: 1. die direkte Fermentation des Adsorbers mit lipolytisch aktiven Clostridien, 2. der Einsatz von Lipasen und die Fermentation des resultierenden {\"U}berstands und 3. die Kofermentation mit einer lipolytisch aktiven Hefe. Jeder der drei Ans{\"a}tze f{\"u}hrte zu einerHydrolyse des {\"O}ls und Wachstum der Mikroorganismen. Der Einsatz von Lipasen resultierte in einer vollst{\"a}ndigen und der schnellsten Hydrolyse des {\"O}ls. Eine Glycerinkonzentration von 13,4 g/L konnte erreicht werden. Die anaerobe Fermentation der verschiedenen Clostridien auf Minimalmedien verlief erfolgreich. Der Vergleich der Fermentationen der Bleicherdehydrolysate zeigte, dass das Hydrolysat wachstumsinhibierende Substanzen enth{\"a}lt. Unter diesen Bedingungen konnte eine Ausbeute von Y P/S = 0,11 erzielt werden. Der Einsatz eines Ionenaustauschers zur Reinigung des Hydrolysats vor der Fermentation resultierte in einer Verbesserung des Wachstums}, language = {de} } @misc{DuweTippkoetterLeipoldetal.2012, author = {Duwe, A. and Tippk{\"o}tter, Nils and Leipold, D. and Riemer, S. and Zorn, H. and Ulber, Roland}, title = {Holzhydrolyse als Feststoffreaktion: Charakterisierung von Inhibitoren und Erh{\"o}hung der Ausbeute durch den Einsatz lignolytischer Enzyme}, series = {Chemie Ingenieur Technik}, volume = {84}, journal = {Chemie Ingenieur Technik}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201250298}, pages = {1307}, year = {2012}, abstract = {Der Erhalt m{\"o}glichst hoher Zuckerkonzentrationen f{\"u}r nachfolgende Fermentationen und eine Steigerung der Produktivit{\"a}t sind Ziele der Hydrolyse bei hohen Feststoffkonzentrationen im Rahmen des Projekts „Lignocellulose Bioraffinerie". Verwendet wird durch ein Organosolv-Verfahren aufgeschlossenes Buchenholz. Die Hydrolyse des Faserstoffes erfolgt mithilfe von CTec2-Enzymen (Fa. Novozymes). Zurzeit k{\"o}nnen unter Einsatz eines neuen Feststoffreaktors Cellulosefasern in einer Konzentration bis 400 g L⁻¹ enzymatisch hydrolysiert werden. Dabei werden Ausbeuten (g Glucose/g Cellulose im Faserstoff) bis 0,86 g g⁻¹ und Glucosekonzentrationenvon 120 g L⁻¹ erreicht. Ein Nachteil ist jedoch die hierbei auftretende Abnahme der Hydrolyseausbeuten. Zahlreiche Limitierungen bez{\"u}glich der Hydrolysierbarkeit von Lignocellulose werden zurzeit diskutiert und publiziert. Ziel der Untersuchungen ist die Identifizierung hydrolysehemmender Substanzen sowie die Erh{\"o}hung der Ausbeute an Zuckermonomeren durch den Einsatz lignolytischer Enzyme. Hierbei wird eine HPLC-MS-Methode zur Charakterisierung hemmender Substanzen eingesetzt, um potenzielle Inhibitoren zu erfassen.}, language = {de} } @misc{PothMonzonTippkoetteretal.2009, author = {Poth, S. and Monzon, M. and Tippk{\"o}tter, Nils and Ulber, Roland}, title = {Fermentation von Hydrolysaten aus Lignocellulose}, series = {Chemie Ingenieur Technik}, volume = {81}, journal = {Chemie Ingenieur Technik}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.200950243}, pages = {1220}, year = {2009}, abstract = {Die {\"o}konomische Abh{\"a}ngigkeit von fossilen Brennstoffen und der klimatische Wandel durch die Nutzung dieser haben zu einer intensiven Suche nach erneuerbaren Rohstoffen f{\"u}r die Produktion von Chemikalien und Treibstoffen gef{\"u}hrt. Ein viel versprechender Rohstoff in diesem Zusammenhang sind Zucker, die mittels enzymatischer Hydrolyse aus Lignocellulose gewonnen werden k{\"o}nnen. Die Fermentation erfolgt mit Cellulose- bzw. Hemicellulose-Fraktionen, welche durch thermo-chemische Vorbehandlung von Holz gewonnen und anschließend enzymatisch hydrolysiert werden. Die in den Hydrolysaten enthaltenen Zuckermonomere dienen als Kohlenstoffquelle f{\"u}r die Produktion von Ethanol. Da sowohl Glucose als auch Xylose in den unterschiedlichen Fraktionen enthalten sind, wird zur Umsetzung dieser eine Co-Fermentation zweier Hefen durchgef{\"u}hrt. Im Rahmen der Optimierung dieser Fermentationen werden neben der Erg{\"a}nzung der Hydrolysate durch notwendige Salze auch Verfahrenweisen wie Fed-Batch-Fermentationen untersucht. Ein weiterer interessanter Ansatz, welcher in diesem Rahmen gepr{\"u}ft wird, ist die enzymatische Hydrolyse der Lignocellulose-Fraktionen und die simultane Fermentation der dabei entstehenden Zucker in einem Schritt. Des Weiteren wurde die Eignung der Hydrolysate f{\"u}r die Biomasseproduktion anderer Mikroorganismen wie Escherichia coli getestet.}, language = {de} } @misc{HeringUlberTippkoetter2014, author = {Hering, T. and Ulber, Roland and Tippk{\"o}tter, Nils}, title = {Aktiver und passiver antimikrobieller Oberfl{\"a}chenschutz durch funktionalisierte Mikropartikel}, series = {Chemie Ingenieur Technik}, volume = {9}, journal = {Chemie Ingenieur Technik}, number = {86}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201450264}, pages = {1474 -- 1475}, year = {2014}, abstract = {Mikrobielle Verunreinigungen von Oberfl{\"a}chen in technischen und medizinischen Systemen sind allgegenw{\"a}rtig. Sie basieren {\"u}blicherweise auf adsorptiven Oberfl{\"a}chenbindungen organischer Komponenten (Proteine und Fette) oder Membrankomponenten aerogener sowie wassergebundener Mikroorganismen. In laufenden Forschungsarbeiten wird eine aktive sowie passive Biomodifikation von Oberfl{\"a}chen zu deren Schutz vor Adsorption von Proteinen und Mikroorganismen verfolgt. Der antimikrobielle Schutz soll dabei sowohl durch die Mikrostrukturierung bzw. Rauheitsanpassung der Oberfl{\"a}chen durch deren Beschichtung mit Mikro-und Nanopartikeln erfolgen. Ferner werden antimikrobielle Enzyme und funktionelle Gruppen auf den Mikropartikeln gebunden, um den Oberfl{\"a}chenschutz zu verst{\"a}rken. In ersten Versuchen wurden quart{\"a}re Ammoniumverbindungen auf eigens synthetisierten superparamagnetischen Eisenoxid-Nanopartikeln (Durchmesser 10 - 30 nm) immobilisiert und die wachstumshemmende Wirkung untersucht. Erste Ergebnisse zeigten, dass eine Konzentration von 10 mg mL⁻¹ der Ammoniumverbindung in einer Wachstumshemmung des verwendeten Gram-negativen Modell-Mikroorganismus E. coli GFPmut2 resultiert. Zurzeit werden synergistisch wirkende Kombinationen von Partikeln mit Proteasen, quart{\"a}ren Ammoniumverbindungen, hydrophoben Oberfl{\"a}chen und mikrostrukturierten Oberfl{\"a}chen als antimikrobieller Schutz untersucht.}, language = {de} } @misc{BraunKrafftTippkoetter2022, author = {Braun, Lena and Krafft, Simone and Tippk{\"o}tter, Nils}, title = {Combined supercritical carbon dioxide extraction and chromatography of the algae fatty linoleic and linolenic acid}, series = {Chemie Ingenieur Technik}, volume = {94}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.202255308}, pages = {1304}, year = {2022}, abstract = {A method for the integrated extraction and separation of fatty acids from algae using supercritical CO2 is presented. Desmodesmus obliquus and Chlorella sorokiniana were used as algae. First, a method for chromatographic separation of fatty acids of different degrees of saturation was established and optimized. Then, an integrated method for supercritical extraction was developed for both algal species. It was also verified whether prior cell disruption was beneficial for extraction. In developing the method for chromatographic separation, statistical experimental design was used to determine the optimal parameter settings. The methanol content in the mobile phase proved to be the most important parameter for successful separation of the three unsaturated fatty acids oleic acid, linoleic acid, and linolenic acid. Supercritical extraction with dried algae showed that about four times more fatty acids can be extracted from C. sorokiniana relative to the dry mass used.}, language = {en} } @misc{SchumannRoginSchneideretal.2012, author = {Schumann, C. and Rogin, S. and Schneider, H. and Oster, J. and Tippk{\"o}tter, Nils and Kampeis, P.}, title = {Steuerung von HGMS-Prozessen mittels Durchflusszytometrie}, series = {Chemie Ingenieur Technik}, volume = {84}, journal = {Chemie Ingenieur Technik}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201250125}, pages = {1370}, year = {2012}, abstract = {Die Hochgradientenmagnetseparation (HGMS) ist eine Methode zur Aufreinigung von biopharmazeutischen Produkten. Mit dieser Methode l{\"a}sst sich in nur einem Schritt eine Fest/Fest/Fl{\"u}ssig-Trennung erzielen, was zu einer erheblichen Zeit- und Kostenersparnis im Downstreaming f{\"u}hrt. Dennoch steht ihr industrieller Einsatz noch aus, was u. a. am Mangel an Analysenmethoden liegt, um die HGMS quantifizierbar zu machen. Gerade in der Pharmaproduktion werden Prozesse gebraucht, die gem{\"a}ß den einschl{\"a}gigen Vorschriften (cGMP) validiert und deren verfahrenstechnische Anlagenteile qualifiziert werden k{\"o}nnen. Die Schwierigkeit ist die Messung der magnetischen Mikrosorbentien in der Suspension, in der auch Zellen oder Zelltr{\"u}mmer vorliegen. Im Rahmen eines Forschungsprojektes im „Zentralen Innovationsprogramm Mittelstand" des BMWi wurden verschiedene Analysenmethoden untersucht. Die Durchflusszytometrie erm{\"o}glicht eine Charakterisierung von Partikeln und eine simultane quantitative Messung. Durch die multiparametrige Messung kann zwischen Zellen, Zelltr{\"u}mmern und Magnetpartikeln unterschieden werden. Die At-line-Einbindung des Durchflusszytometers ist durch den Einsatz einer externen Pumpe m{\"o}glich. {\"U}ber eine automatisierte Messwertanalyse kann der HGMS-Prozess mittels der Durchflusszytometrie gesteuert werden.}, language = {de} } @article{PennerUsherovichNiedermeieretal.2022, author = {Penner, Crystal and Usherovich, Samuel and Niedermeier, Jana and B{\´e}langer-Champagne, Camille and Trinczek, Michael and Paulßen, Elisabeth and Hoehr, Cornelia}, title = {Organic Scintillator-Fibre Sensors for Proton Therapy Dosimetry: SCSF-3HF and EJ-260}, series = {electronics}, volume = {12}, journal = {electronics}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {2079-9292}, doi = {10.3390/electronics12010011}, pages = {12 Seiten}, year = {2022}, abstract = {In proton therapy, the dose from secondary neutrons to the patient can contribute to side effects and the creation of secondary cancer. A simple and fast detection system to distinguish between dose from protons and neutrons both in pretreatment verification as well as potentially in vivo monitoring is needed to minimize dose from secondary neutrons. Two 3 mm long, 1 mm diameter organic scintillators were tested for candidacy to be used in a proton-neutron discrimination detector. The SCSF-3HF (1500) scintillating fibre (Kuraray Co. Chiyoda-ku, Tokyo, Japan) and EJ-260 plastic scintillator (Eljen Technology, Sweetwater, TX, USA) were irradiated at the TRIUMF Neutron Facility and the Proton Therapy Research Centre. In the proton beam, we compared the raw Bragg peak and spread-out Bragg peak response to the industry standard Markus chamber detector. Both scintillator sensors exhibited quenching at high LET in the Bragg peak, presenting a peak-to-entrance ratio of 2.59 for the EJ-260 and 2.63 for the SCSF-3HF fibre, compared to 3.70 for the Markus chamber. The SCSF-3HF sensor demonstrated 1.3 times the sensitivity to protons and 3 times the sensitivity to neutrons as compared to the EJ-260 sensor. Combined with our equations relating neutron and proton contributions to dose during proton irradiations, and the application of Birks' quenching correction, these fibres provide valid candidates for inexpensive and replicable proton-neutron discrimination detectors}, language = {en} } @article{NiedermeierPennerUsherovichetal.2023, author = {Niedermeier, Jana and Penner, Crystal and Usherovich, Samuel and B{\´e}langer-Champagne, Camille and Paulßen, Elisabeth and Hoehr, Cornelia}, title = {Optical Fibers as Dosimeter Detectors for Mixed Proton/Neutron Fields - A Biological Dosimeter}, series = {electronics}, volume = {12}, journal = {electronics}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2079-9292}, doi = {10.3390/electronics12020324}, pages = {11 Seiten}, year = {2023}, abstract = {In recent years, proton therapy has gained importance as a cancer treatment modality due to its conformality with the tumor and the sparing of healthy tissue. However, in the interaction of the protons with the beam line elements and patient tissues, potentially harmful secondary neutrons are always generated. To ensure that this neutron dose is as low as possible, treatment plans could be created to also account for and minimize the neutron dose. To monitor such a treatment plan, a compact, easy to use, and inexpensive dosimeter must be developed that not only measures the physical dose, but which can also distinguish between proton and neutron contributions. To that end, plastic optical fibers with scintillation materials (Gd₂O₂S:Tb, Gd₂O₂S:Eu, and YVO₄:Eu) were irradiated with protons and neutrons. It was confirmed that sensors with different scintillation materials have different sensitivities to protons and neutrons. A combination of these three scintillators can be used to build a detector array to create a biological dosimeter.}, language = {en} } @misc{HeringUlberTippkoetter2016, author = {Hering, T. and Ulber, Roland and Tippk{\"o}tter, Nils}, title = {Antimikrobielle Oberfl{\"a}chenmodifikation durch Mikropartikel}, series = {Chemie Ingenieur Technik}, volume = {88}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, doi = {10.1002/cite.201650084}, pages = {1302}, year = {2016}, abstract = {Die Ausbildung von Biofilmen in technischen Anlagen, wie z. B. K{\"u}hlkreisl{\"a}ufen, Wasseraufbereitungssystemen und Bioreaktoren, f{\"u}hren zu Materialsch{\"a}den (Biofouling) und stark erh{\"o}htem Energieaufwand. Im Rahmen der aktuellen Forschungsarbeiten erfolgen aktive sowie passive Bio-Modifikationen auf funktionalisierten magnetischen Mikropartikelober-fl{\"a}chen. Um die verschiedenen funktionalisierten magnetischen Mikropartikel zu analysieren und ihre antimikrobielle Wirkung zu testen, wird der Einsatz einer 3D-gedruckten, magnetischen Plattform f{\"u}r ein Fluoreszenz-basiertes Screening-System untersucht. F{\"u}r den Oberfl{\"a}chenschutz wurden verschiedene, antimikrobiell funktionalisierte Partikelkombinationen mit dem Mikroorganismus Escherichia coli GFPmut2 in Bezug auf aktiven Oberfl{\"a}chenschutz verglichen. Um die antimikrobielle Oberfl{\"a}cheneffekte von synergistischen Kombinationen unterschiedlich funktionalisierter Partikel zu bestimmen, werden Oberfl{\"a}chen einem Magnetfeld ausgesetzt, das die Mikropartikel als definierte Schicht auf ihnen zur{\"u}ck h{\"a}lt. Diese modifizierten Oberfl{\"a}chen k{\"o}nnen sowohl durch Fluoreszenzspektroskopie als auch -mikroskopie analysiert werden.}, language = {de} } @misc{TippkoetterMoehring2014, author = {Tippk{\"o}tter, Nils and M{\"o}hring, S.}, title = {Nutzung von F{\"a}ulepilzen f{\"u}r die selektive Gewinnung von Cellulose und Lignin aus nicht vorbehandelter lignocellulosehaltiger Biomasse}, series = {Chemie Ingenieur Technik}, volume = {86}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201450353}, pages = {1385}, year = {2014}, abstract = {Einige Arten der Braun- und Weißf{\"a}ulepilze sind in der Lage, selektiv entweder Lignin oder Cellulose im Holz abzubauen. Diese Pilze k{\"o}nnen f{\"u}r eine energiesparende Vorbehandlung lignocellulosehaltiger Biomasse f{\"u}r Bioraffinerien genutzt werden, ohne auf technisch aufw{\"a}ndige Aufschlussapparate zur{\"u}ckgreifen zu m{\"u}ssen. Weißf{\"a}ulepilze bauen bevorzugt Lignin ab, wodurch die verbleibende Cellulose leichter f{\"u}r enzymatische Hydrolysen in das Monosaccharid Glucose zug{\"a}nglich wird. Braunf{\"a}ulepilze bauen dagegen Cellulose und Hemicellulose ab. Die Auswirkungen der Behandlung von Weizenstroh mit verschiedenen Pilzarten werden zurzeit untersucht. Dabei werden die Ver{\"a}nderung der enzymatischen Hydrolysierbarkeit des Substrats sowie die gebildeten Ligninderivate bestimmt. Detaillierte Betrachtungen der Biomassever{\"a}nderung werden mithilfe spezifischer F{\"a}rbemethoden durchgef{\"u}hrt, durch die morphologische Ver{\"a}nderungen der Pflanzengewebe in der 3D-Lichtmikroskopie dargestellt werden k{\"o}nnen.}, language = {de} } @misc{KuthanAlKaidyTippkoetter2016, author = {Kuthan, K. and Al-Kaidy, Huschyar and Tippk{\"o}tter, Nils}, title = {Tropfenbasierte Enzymreaktionen auf Glasoberfl{\"a}chen im μL-Maßstab mit ortsaufgel{\"o}ster pL-Dosierung der Reaktanden}, series = {Chemie Ingenieur Technik}, volume = {88}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, doi = {10.1002/cite.201650117}, pages = {1336 -- 1337}, year = {2016}, abstract = {Mit der Entwicklung w{\"a}ssriger Tropfen, die mit einer sch{\"u}tzenden H{\"u}lle magnetisierbarer, hydrophober Partikel umgeben sind, ergeben sich neue M{\"o}glichkeiten im Bereich der Mikrofluidik. So k{\"o}nnen die Tropfen als fl{\"u}ssige Mikroreaktoren eingesetzt werden. Der w{\"a}ssrige Kern dieser Mikroreaktoren besteht aus einer Substratl{\"o}sung f{\"u}r enzymatische Umsetzungen. Durch Bewegen der Mikroreaktoren k{\"o}nnen diese {\"u}ber immobilisierten Enzymen positioniert werden, um so einen enzymatischen Umsatz innerhalb der Mikroreaktoren zu realisieren. Hierf{\"u}r wurde eine neue Mikroreaktorplattform-Technologie etabliert. Die Mikroreaktoren k{\"o}nnen aufgrund ihrer magnetisierbaren H{\"u}llenpartikel {\"u}ber elektromagnetische Spulen bewegt werden. Die Bewegung erfolgt dabei mit einer automatisierten Aktuatorplattform, bestehend aus einer 3x3 Doppelspulenmatrix mit Magnetkernen. Als modellhaftes Reaktionssystem wird eine Enzymkaskade eingesetzt, die sich aus einer b-Glucosidase, Glucose-Oxidase und Meerrettichperoxidase zusammensetzt. Prim{\"a}r untersuchte Substrate sind Fluorescein-di-b-D-glucopyranoside, und 1-(3,7-Dihydroxy-10H-phenoxazin-10-yl)-ethanon, bei deren Umsatz fluoreszierende Produkte entstehen.}, language = {de} } @misc{WulfhorstMerseburgTippkoetter2016, author = {Wulfhorst, H. and Merseburg, J. and Tippk{\"o}tter, Nils}, title = {Batteriekomponenten aus nachwachsenden Rohstoffen}, series = {Chemie Ingenieur Technik}, volume = {88}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201650333}, pages = {1234 -- 1235}, year = {2016}, abstract = {In diesem Beitrag geht es um die Integration von Stoffstr{\"o}men einer Lignocellulose-Bioraffinerie in Verfahren zur Batterieherstellung. Pflanzliche Reststoffe aus der Biokraftstoffherstellung wie Lignin sollen zur Herstellung neuer Batteriematerialien verwendet werden. Hierbei wird das Lignin als Matrix f{\"u}r die vorgraphitischen C-haltigen Einlagerungsverbindungen in den Elektroden genutzt. Die Si-C-Komposite werden durch das Einbetten von Si in eine Ligninmatrix mit anschließender Carbonisierung hergestellt. Das Lignin hierf{\"u}r wird durch die sequentielle hydrothermale Vorbehandlung von Buchenholz bei variablen Bedingungen gewonnen und mit Si-Nanopartikel sowie als Referenz ohne Si-Nanopartikel gef{\"a}llt. Die Ergebnisse zeigen, dass die sequenzielle Vorbehandlung h{\"o}here Ausbeuten im Vergleich zum LHW- oder Organosolv-Aufschluss liefert. Um eine Anode herzustellen, wurde das resultierende Si-C-Kompositmaterial carbonisiert, auf einen Stromsammler aufgetragen und elektro-chemisch charakterisiert. Der Einfluss der Vorbehandlungsschritte auf den Herstellungsprozess und die {\"o}konomische Bewertung des untersuchten Bioraffinerie-Prozesses wurde mithilfe eines Stoffstrommodells analysiert.}, language = {de} } @misc{EngelBayerUlberetal.2018, author = {Engel, Mareike and Bayer, Hendrik and Ulber, Roland and Tippk{\"o}tter, Nils}, title = {Kommt es in Elektrofermentationen mit Clostridium acetobutylicum zu einer Eisenlimitierung?}, series = {Chemie Ingenieur Technik}, volume = {90}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201855047}, pages = {1154}, year = {2018}, abstract = {Das strikt anaerobe Bakterium Clostridium acetobutylicum bildet die L{\"o}semittel Aceton, Butanol und Ethanol (ABE-Fermentation). Im Fall einer Eisenlimitierung kommt es zus{\"a}tzlich zu einer Riboflavinsekretion (RF), was durch die gelbe F{\"a}rbung des Kultur{\"u}berstands erkennbar ist. In dieser Arbeit wurde beobachtet, dass w{\"a}hrend Elektrofermentationen mit C. acetobutylicum bei -600 mV eine gelbe F{\"a}rbung auftritt. Es wurde deshalb untersucht, ob eine Eisenlimitierung im bio-elektrochemischen System (BES) vorliegt. Hierzu wurden die Flavinspezien bei Kultivierungen in Medien mit einer Eisenlimitierung bzw. mit ausreichend Eisen in Serumflaschen sowie im BES mit und ohne angelegtem Potenzial verglichen. In den Serumflaschenversuchen wurden RF und Flavinadenindinukleotid (FAD)-Konzentrationen von ‡ 20 mg L⁻¹ sowie Flavinmononukleotid (FMN)-Konzentrationen von ca. 5 mg L⁻¹ detektiert. Bei ausreichender Eisenverf{\"u}gbarkeit hingegen wurden in den Serumflaschen fast keine Flavine sekretiert. Im BES bei -600 mV hingegen wurde auch in diesen Kultur{\"u}berst{\"a}nden FMN und FAD (1-5 mg L⁻¹ ),jedoch kein RF gemessen. Diese Ergebnisse zeigen, dass die Flavinbildung im BES mit angelegtem Potenzial nicht mit der Flavinbildung unter Eisenlimitierung in Serumflaschen korreliert. Andere Faktoren f{\"u}r eine m{\"o}gliche Flavinbildung werden aktuell n{\"a}her betrachtet.}, language = {de} } @misc{CapitainHeringTippkoetter2016, author = {Capitain, C. and Hering, T. and Tippk{\"o}tter, Nils}, title = {Enzymatische Polymerisation von Ligninmodellkomponenten und Organosolv-Lignin mit aromatischen Aminos{\"a}uren}, series = {Chemie Ingenieur Technik}, volume = {88}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201650374}, pages = {1236}, year = {2016}, abstract = {Die stoffliche Nutzung von Lignin aus Bioraffinerien ist ein wichtiger Bestandteil f{\"u}r den Wertsch{\"o}pfungsprozess von nachwachsenden, pflanzlichen Rohstoffen. Lignin z{\"a}hlt zu den wenigen erneuerbaren Quellen f{\"u}r phenolische Bestandteile, wird aber derzeit meist nur thermisch verwertet. Ziel dieses Forschungsvorhabens ist die Funktionalisierung von Lignin zur Verbesserung der Adh{\"a}sionseigenschaften. Als funktionelle Gruppe wird die aromatische Aminos{\"a}ure L-DOPA verwendet, die charakteristisch f{\"u}r die Adh{\"a}sionskraft von Muscheln ist. Lignin ist ein geeignetes St{\"u}tzger{\"u}st, da es ein Polymer ist, das durch enzymkatalysierte Polymerisation gebildet wird. Essenziell f{\"u}r die Entwicklung ist ein besseres Verst{\"a}ndnis {\"u}ber die Bildung von Lignin-Polymeren und deren verschiedene Eigenschaften. Um die Einflussfaktoren auf Kettenl{\"a}nge und Polymerisationseffizienz zu untersuchen, werden zurzeit sowohl Ligninmodellkomponenten (LMK) als auch gel{\"o}stes Organosolv-Lignin verwendet. Laufende Untersuchungen werden zeigen, ob sich die enzymatische Polymerisationsreaktion auf ein gel{\"o}stes Ligninpolymer aus einem Organosolv-Aufschluss {\"u}bertragen l{\"a}sst.}, language = {de} } @misc{CapitainLukebaUlberetal.2018, author = {Capitain, C. C. and Lukeba, L. and Ulber, Roland and Tippk{\"o}tter, Nils}, title = {Biomimetische Klebstoffe aus Organosolv-Lignin}, series = {Chemie Ingenieur Technik}, volume = {90}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201855076}, pages = {1167}, year = {2018}, abstract = {Aufgrund von EU-Regularien und Umweltinitiativen w{\"a}chst der Markt f{\"u}r nachhaltige und abbaubare Klebstoffe stetig. Organosolv (OS)-Lignin ist ein kommerziell wenig ertragreicher Nebenstrom der Lignocellulose-Bioraffinerie. Durch das "Nachahmen" der Adh{\"a}sionseigenschaften mit strukturverwandten Muschel-Aminos{\"a}uren soll OS-Lignin in einen starkes, vollst{\"a}ndig biobasiertes Adh{\"a}siv umgewandelt werden. Funktionsweisend f{\"u}r die Adh{\"a}sion des Muschelklebstoffes ist die Catecholgruppe der Aminos{\"a}ure L-DOPA. Die laccase-katalysierte Polymerisationsreaktion von Lignin und L-DOPA ist schwierig zu kontrollieren, da L-DOPA eine Ringschlussreaktion eingeht. Stattdessen wurde eine zweistufige Reaktion mit einem Diamin als Ankermolek{\"u}l etabliert. Die Catecholgruppe, die im zweiten Schritt enzymatisch an das Lignin-Amin gebunden wird, kann durch Komplexbildung mit Fe(III)-Ionen sowohl zur Adh{\"a}sion als auch zur Koh{\"a}sion des Klebstoffes beitragen. Der Lignin-Catechol-Klebstoff ist frei von petrochemischen Chemikalien und biologisch abbaubar. In ersten Stirnzugversuchen konnte eine Haftkraft von 0,3 MPa erreicht werden.}, language = {de} } @article{OjovanSteinmetz2022, author = {Ojovan, Michael I. and Steinmetz, Hans-J{\"u}rgen}, title = {Approaches to Disposal of Nuclear Waste}, series = {Energies}, volume = {15}, journal = {Energies}, number = {20}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {10.3390/en15207804}, pages = {Artikel 7804}, year = {2022}, abstract = {We present a concise mini overview on the approaches to the disposal of nuclear waste currently used or deployed. The disposal of nuclear waste is the end point of nuclear waste management (NWM) activities and is the emplacement of waste in an appropriate facility without the intention to retrieve it. The IAEA has developed an internationally accepted classification scheme based on the end points of NWM, which is used as guidance. Retention times needed for safe isolation of waste radionuclides are estimated based on the radiotoxicity of nuclear waste. Disposal facilities usually rely on a multi-barrier defence system to isolate the waste from the biosphere, which comprises the natural geological barrier and the engineered barrier system. Disposal facilities could be of a trench type, vaults, tunnels, shafts, boreholes, or mined repositories. A graded approach relates the depth of the disposal facilities' location with the level of hazard. Disposal practices demonstrate the reliability of nuclear waste disposal with minimal expected impacts on the environment and humans.}, language = {en} } @techreport{Tippkoetter2021, author = {Tippk{\"o}tter, Nils}, title = {TreBec - Herstellung eines Mehrwegbechers aus Treber : Sachbericht zum Verwendungsnachweis}, publisher = {FH Aachen}, address = {J{\"u}lich}, doi = {10.2314/KXP:1858723302}, pages = {10 Seiten}, year = {2021}, abstract = {Laufzeit des Vorhabens und Berichtszeitraum: 01.10.2020-30.09.2021}, language = {de} } @misc{SiekerTippkoetterUlberetal.2009, author = {Sieker, T. and Tippk{\"o}tter, Nils and Ulber, Roland and Bart, Hans-J{\"o}rg and Heinzle, E.}, title = {Nutzung von Silage zur fermentativen Produktion von Grund-und Feinchemikalien}, series = {Chemie Ingenieur Technik}, volume = {81}, journal = {Chemie Ingenieur Technik}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.200950271}, pages = {1207}, year = {2009}, abstract = {Grasschnitt hat in Deutschland ein betr{\"a}chtliches Potenzial als nachwachsender Rohstoff. Da frischer Grasschnitt nur in den Sommermonaten zur Verf{\"u}gung steht und Gras bei der Lagerung verrottet, wird er unter anderem durch Silierung konserviert. W{\"a}hrend der Silierung wird ein Teil der wasserl{\"o}slichen Kohlenhydrate unter anaeroben Bedingungen zu Milchs{\"a}ure fermentiert. Die Kombination aus Luftabschluss und Ans{\"a}uerung bewirkt die Konservierung der Silage. Silage als weit verbreitetes landwirtschaftliches Erzeugnis ist somit ein potentieller, in großen Mengen verf{\"u}gbarer Lieferant f{\"u}r eine Vielzahl von Substraten f{\"u}r mikrobielle Fermentationen. Diese k{\"o}nnen entweder durch die Hydrolyse der in den Pflanzen enthaltenen Cellulosen und Hemicellulosen oder durch die Verwendung eines Silagepresssaftes nutzbar gemacht werden. Die zu entwickelnden Prozesse sollen die verbleibenden Kohlenhydrate, inklusive der Cellulose und Hemicellulose, sowie die Milchs{\"a}ure nutzen. Die in der Silage enthaltenen Zucker sollen zu Ethanol, Itakons{\"a}ure und Bernsteins{\"a}ure und die Milchs{\"a}ure zu 1,2-Propandiol umgesetzt werden. Anfallende Reststoffe wie Hydrolyser{\"u}ckst{\"a}nde, Presskuchen und Fermentationsr{\"u}ckst{\"a}nde sollen bei allen zu etablierenden Prozessen entweder als Viehfutter verwendet oder der Biogasproduktion zugef{\"u}hrt werden k{\"o}nnen, wodurch eine vollst{\"a}ndige stoffliche und energetische Nutzung der Silage erreicht wird.}, language = {de} } @misc{ThielTippkoetterMuffleretal.2012, author = {Thiel, A. and Tippk{\"o}tter, Nils and Muffler, K. and Ruf, F. and Sohling, U. and Ulber, Roland}, title = {Optimierung der Wertsch{\"o}pfungskette bei der Aufarbeitung von Rapsschrot mit Zeolithen}, series = {Chemie Ingenieur Technik}, volume = {84}, journal = {Chemie Ingenieur Technik}, number = {8}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0009-286X}, doi = {10.1002/cite.201250028}, pages = {1191 -- 1192}, year = {2012}, abstract = {Im vom BMELV/FNR gef{\"o}rderten SynRg-Projekt wurde unter anderem Rapsschrot untersucht, um Polyphenole zu isolieren und aufzureinigen. Diese sollen anschließend als Basisbausteine f{\"u}r Polymere dienen und ihnen neuartige Eigenschaften verleihen. Derzeit wird an der Polyphenolextraktion gearbeitet, da bei organischen oder w{\"a}ssrigen Extraktionsprozessen {\"u}berwiegend Sinapin, ein Cholinester der Sinapins{\"a}ure, vorliegt und dieses nicht f{\"u}r die Polymerbildung eingesetzt werden kann. F{\"u}r die im Fokus stehende Sinapins{\"a}ure wird deshalb eine simultane Extraktion und enzymatische oder chemische Hydrolyse von Sinapin zu Sinapins{\"a}ure durchgef{\"u}hrt. Durch die Hydrolyse konnte die Sinapins{\"a}ureausbeute bereits um den Faktor 6,2 auf 15,8 mg g⁻¹ gegen{\"u}ber einer reinw{\"a}ssrigen Extraktion gesteigert werden. F{\"u}r die Aufreinigung des an Sinapins{\"a}ure reichen Extrakts erfolgt anschließend ein adsorptiver Aufarbeitungsschritt, bei dem Zeolithe zum Einsatz kommen. Mit diesem Material ist es m{\"o}glich, die Sinapins{\"a}ure quantitativ zu adsorbieren und sp{\"a}ter mit 70 \%igem Ethanol bei 60 °C zu desorbieren. Bei den Adsorbern handelt es sich um b-Zeolithe von der S{\"u}d-Chemie AG.}, language = {de} } @article{GrosshauserPettrak2023, author = {Großhauser, Christian and Pettrak, J{\"u}rgen}, title = {Die Rolle des Wasserstoffs in der Abwasserbehandlung}, series = {Wasser und Abfall}, journal = {Wasser und Abfall}, number = {7/8}, publisher = {Springer Fachmedien}, address = {Wiesbaden}, issn = {1436-9095}, doi = {10.1007/s35152-023-1444-4}, year = {2023}, abstract = {Die Bereitstellung von nachhaltig erzeugtem Wasserstoff als Energietr{\"a}ger und Rohstoff ist eine wichtige Schl{\"u}sseltechnologie sowohl als Ersatz f{\"u}r fossile Energietr{\"a}ger, aber auch als Produkt im Zusammenhang mit Kreislaufprozessen. In der Abwasserbehandlung bestehen verschiedene M{\"o}glichkeiten Wasserstoff herzustellen. Mehrere Wege, m{\"o}gliche Synergien, aber auch deren Nachteile werden vorgestellt.}, language = {de} }