TY  - JOUR
A1  - Henderson, Colin J.
A1  - Mclaughlin, Lesley A.
A1  - Scheer, Nico
A1  - Stanley, Lesley A.
A1  - Wolf, C. Roland
T1  - Cytochrome b5 Is a Major Determinant of Human Cytochrome P450 CYP2D6 and CYP3A4 Activity In Vivo s
JF  - Molecular Pharmacology
Y1  - 2015
U6  - https://doi.org/10.1124/mol.114.097394
SN  - 1521-0111
VL  - 87
IS  - 4
SP  - 733
EP  - 739
PB  - ASPET
CY  - Bethesda
ER  - 
TY  - JOUR
A1  - Kapelyukh, Yury
A1  - Henderson, Colin James
A1  - Scheer, Nico
A1  - Rode, Anja
A1  - Wolf, Charles Roland
T1  - Defining the contribution of CYP1A1 and CYP1A2 to drug metabolism using humanized CYP1A1/1A2 and Cyp1a1/Cyp1a2 KO mice
JF  - Drug Metabolism and Disposition
Y1  - 2019
U6  - https://doi.org/10.1124/dmd.119.087718
IS  - Early view
ER  - 
TY  - JOUR
A1  - Falkenberg, Fabian
A1  - Bott, Michael
A1  - Bongaerts, Johannes
A1  - Siegert, Petra
T1  - Phylogenetic survey of the subtilase family and a data-mining-based search for new subtilisins from Bacillaceae
JF  - Frontiers in Microbiology
N2  - 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.
Y1  - 2022
U6  - https://doi.org/10.3389/fmicb.2022.1017978
SN  - 1664-302X
VL  - 2022
IS  - 13
PB  - Frontiers
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Danho, Waleed
A1  - Naithani, Vinod K.
A1  - Sasaki, André N.
A1  - Föhles, Joseph
A1  - Berndt, Heinz
A1  - [u.a.], 
T1  - Human proinsulin, VII : synthesis of two protected peptides corresponding to the sequences 1—45 and 46—86 of the prohormone
JF  - Hoppe-Seyler's Zeitschrift für physiologische Chemie
Y1  - 1980
U6  - https://doi.org/10.1515/bchm2.1980.361.1.857
SN  - 1437-4315
SN  - 0018-4888
VL  - 361
IS  - 1
SP  - 857
EP  - 863
ER  - 
TY  - CHAP
A1  - Berndt, Heinz
A1  - Turck, Christoph W.
ED  - Voelter, Wolfgang
T1  - Syntheses of defined peptide derivatives by aminolysis of 3-[Nα-benzyloxycarbonyl peptidyloxy] -2-hydroxy-N-methyl-benzamides at elevated temperatures II. Synthesis of the peptide derivatives Z-Ala-X-Gly-N(Et)2, X=Phe, Leu, Val, Ser (But), Glu (OBut)
T2  - Chemistry of peptides and proteins : proceedings of the Fourth USSR-FRG Symposium, Tübingen, Federal Republic of Germany, June 8 - 12, 1982 / ed. Wolfgang Voelter ... - Vol. 2
Y1  - 1984
SN  - 3-11009-580-7
SP  - 97
EP  - 103
PB  - de Gruyter
CY  - Berlin [u.a.]
ER  - 
TY  - GEN
A1  - Möhring, S.
A1  - Wulfhorst, H.
A1  - Capitain, C.
A1  - Roth, J.
A1  - Tippkötter, Nils
T1  - Fractioning of lignocellulosic biomass: Scale-down and automation of thermal pretreatment for parameter optimization
T2  - Chemie Ingenieur Technik
N2  - 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.
Y1  - 2016
U6  - https://doi.org/10.1002/cite.201650288
SN  - 0009-286X
SN  - 1522-2640 (eISSN)
N1  - ProcessNet-Jahrestagung und 32. DECHEMA-Jahrestagung der Biotechnologen 2016, 12. - 15. September 2016, Eurogress Aachen
VL  - 88
IS  - 9
SP  - 1229
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Welden, Melanie
A1  - Severins, Robin
A1  - Poghossian, Arshak
A1  - Wege, Christina
A1  - Bongaerts, Johannes
A1  - Siegert, Petra
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Detection of acetoin and diacetyl by a tobacco mosaic virus-assisted field-effect biosensor
JF  - Chemosensors
N2  - 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.
Y1  - 2022
U6  - https://doi.org/10.3390/chemosensors10060218
SN  - 2227-9040
N1  - This article belongs to the Special Issue "Nanostructured Devices for Biochemical Sensing"
VL  - 10
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Naithani, V. K
A1  - Klostermeyer, Henning
A1  - Lange, H. R.
A1  - [u.a.], 
A1  - Berndt, Heinz
A1  - [u.a.], 
T1  - Preparation of peptide derivatives for porcine proinsulin-synthesis
JF  - Biological Chemistry
Y1  - 1971
U6  - https://doi.org/10.1515/bchm2.1971.352.1.1
SN  - 1437-4315
VL  - 352
IS  - 1
SP  - 2
EP  - 3
PB  - De Gruyter
ER  - 
TY  - JOUR
A1  - Ojovan, Michael I.
A1  - Steinmetz, Hans-Jürgen
T1  - Approaches to Disposal of Nuclear Waste
JF  - Energies
N2  - 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.
KW  - borehole disposal
KW  - geological disposal
KW  - disposal facility
KW  - retention time
KW  - nuclear waste
Y1  - 2022
U6  - https://doi.org/10.3390/en15207804
SN  - 1996-1073
N1  - This article belongs to the Special Issue "Treatment of Radioactive Waste and Sustainability Energy"
VL  - 15
IS  - 20
PB  - MDPI
CY  - Basel
ER  - 
TY  - CHAP
A1  - Engel, Mareike
A1  - Thieringer, Julia
A1  - Tippkötter, Nils
T1  - Linking bioprocess engineering and electrochemistry for sustainable biofuel production
T2  - Young Researchers Symposium, YRS 2016. Proceedings
N2  - 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.
Y1  - 2016
N1  - Young Researchers Symposium, YRS 2016, 14th - 15th April 2016, Fraunhofer-Zentrum Kaiserslautern
SP  - 49
EP  - 53
PB  - Fraunhofer Verlag
CY  - Karlsruhe
ER  - 
TY  - GEN
A1  - Braun, Lena
A1  - Krafft, Simone
A1  - Tippkötter, Nils
T1  - Combined supercritical carbon dioxide extraction and chromatography of the algae fatty linoleic and linolenic acid
T2  - Chemie Ingenieur Technik
N2  - 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.
Y1  - 2022
U6  - https://doi.org/10.1002/cite.202255308
SN  - 0009-286X
SN  - 1522-2640 (eISSN)
N1  - ProcessNet and DECHEMA‐BioTechNet Jahrestagungen 2022 together with 13th ESBES Symposium 2022, 12. - 15. September 2022, Eurogress Aachen
VL  - 94
IS  - 9
SP  - 1304
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Hengsbach, Jan-Niklas
A1  - Engel, Mareike
A1  - Cwienczek, Marcel
A1  - Stiefelmaier, Judith
A1  - Tippkötter, Nils
A1  - Ulber, Roland
T1  - Scalable unseparated bioelectrochemical reactors by using a carbon fiber brush as stirrer and working electrode
JF  - ChemElectroChem
N2  - 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.
Y1  - 2023
U6  - https://doi.org/10.1002/celc.202300440
SN  - 2196-0216
VL  - 10
IS  - 21
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Tippkötter, Nils
A1  - Ulber, Roland
T1  - Rezension zu: Encyclopedia of Industrial Biotechnology, Vol. 1–7. By MC Flickinger.
JF  - Chemie Ingenieur Technik
Y1  - 2012
U6  - https://doi.org/10.1002/cite.201290052
SN  - 0009-286X
SN  - 1522-2640 (eISSN)
VL  - 6
IS  - 84
SP  - 936
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Tippkötter, Nils
A1  - Möhring, Sophie
A1  - Roth, Jasmine
A1  - Wulfhorst, Helene
T1  - Logistics of lignocellulosic feedstocks: preprocessing as a preferable option
T2  - Biorefineries
N2  - In comparison to crude oil, biorefinery raw materials are challenging in concerns of transport and storage. The plant raw materials are more voluminous, so that shredding and compacting usually are necessary before transport. These mechanical processes can have a negative influence on the subsequent biotechnological processing and shelf life of the raw materials. Various approaches and their effects on renewable raw materials are shown. In addition, aspects of decentralized pretreatment steps are discussed. Another important aspect of pretreatment is the varying composition of the raw materials depending on the growth conditions. This problem can be solved with advanced on-site spectrometric analysis of the material.
KW  - Analytics
KW  - Decentral
KW  - Mechanical
KW  - On-site
KW  - Pre-treatment
Y1  - 2019
SN  - 978-3-319-97117-9
SN  - 978-3-319-97119-3
U6  - https://doi.org/10.1007/10_2017_58
N1  - Advances in biochemical engineering/biotechnology ; Vol. 166
SP  - 43
EP  - 68
PB  - Springer
CY  - Cham
ER  - 
TY  - JOUR
A1  - Penner, Crystal
A1  - Usherovich, Samuel
A1  - Niedermeier, Jana
A1  - Bélanger-Champagne, Camille
A1  - Trinczek, Michael
A1  - Paulßen, Elisabeth
A1  - Hoehr, Cornelia
T1  - Organic Scintillator-Fibre Sensors for Proton Therapy Dosimetry: SCSF-3HF and EJ-260
JF  - electronics
N2  - 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
Y1  - 2022
U6  - https://doi.org/10.3390/electronics12010011
SN  - 2079-9292
N1  - This article belongs to the Special Issue "Applications of Optical Fiber Sensors"
VL  - 12
IS  - 1
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Matoni, Georg
A1  - Berndt, Heinz
T1  - Thermal synthesis of the optical pure pentapeptide derivative Z-(L)-Ala-(L)-Phe-Gly-(L)-Phe-Gly-OMe
JF  - Tetrahedron letters
Y1  - 1980
U6  - https://doi.org/10.1016/S0040-4039(00)93618-9
SN  - 0040-4039
VL  - 21
IS  - 1
SP  - 37
EP  - 40
ER  - 
TY  - JOUR
A1  - El Bergui, Omnia
A1  - Abouabdillah, Aziz
A1  - Bourioug, Mohamed
A1  - Schmitz, Dominik
A1  - Biel, Markus
A1  - Aboudrare, Abdellah
A1  - Krauss, Manuel
A1  - Jomaa, Ahlem
A1  - Romuli, Sebastian
A1  - Müller, Joachim
A1  - Fagroud, Mustapha
A1  - Bouabid, Rachid
T1  - Innovative solutions for drought: Evaluating hydrogel application on onion cultivation (Allium cepa) in Morocco
JF  - Water
N2  - 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.
KW  - water economy
KW  - yield
KW  - deficit irrigation
KW  - hydrogel
KW  - onion
Y1  - 2023
U6  - https://doi.org/10.3390/w15111972
VL  - 15
IS  - 11
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Scheer, Nico
A1  - Kapelyukh, Yury
A1  - Rode, Anja
A1  - Oswald, Stefan
A1  - Busch, Diana
A1  - Mclaughlin, Lesley A.
A1  - Lin, De
A1  - Henderson, Colin J.
A1  - Wolf, C. Roland
T1  - Defining Human Pathways of Drug Metabolism In Vivo through the Development of a Multiple Humanized Mouse Model
JF  - Drug Metabolism and Disposition
Y1  - 2015
U6  - https://doi.org/10.1124/dmd.115.065656
SN  - 1521-009x
VL  - 43
IS  - 11
SP  - 1679
EP  - 1690
PB  - ASPET
CY  - Bethesda
ER  - 
TY  - CHAP
A1  - Berndt, Heinz
A1  - Kalbe, Jochen
A1  - Kuropka, Rolf
A1  - Meyer-Stork, L. Sebastian
A1  - Höcker, Hartwig
ED  - Körner, Andrea
T1  - Progress and limitations of the DNA analysis in fine animal fiber identification
T2  - Proceedings of the 2nd International Symposium on Specialty Animal Fibers : Aachen, October 19 - 20, 1989. - (Schriftenreihe des Deutschen Wollforschungsinstituts an der Technischen Hochschule Aachen e. V. ; 106)
Y1  - 1990
SP  - 259
EP  - 265
PB  - Dt. Wollforschungsinst.
CY  - Aachen
ER  - 
TY  - JOUR
A1  - Zhang, Jin
A1  - Heimbach, Tycho
A1  - Scheer, Nico
A1  - Barve, Avantika
A1  - Li, Wenkui
A1  - Lin, Wen
A1  - He, Handan
T1  - Clinical Exposure Boost Predictions by Integrating Cytochrome P450 3A4–Humanized Mouse Studies With PBPK Modeling
JF  - Journal of Pharmaceutical Sciences
N2  - NVS123 is a poorly water-soluble protease 56 inhibitor in clinical development. Data from in vitro hepatocyte studies suggested that NVS123 is mainly metabolized by CYP3A4. As a consequence of limited solubility, NVS123 therapeutic plasma exposures could not be achieved even with high doses and optimized formulations. One approach to overcome NVS123 developability issues was to increase plasma exposure by coadministrating it with an inhibitor of CYP3A4 such as ritonavir. A clinical boost effect was predicted by using physiologically based pharmacokinetic (PBPK) modeling. However, initial boost predictions lacked sufficient confidence because a key parameter, fraction of drug metabolized by CYP3A4 (ƒₘCYP3A4), could not be estimated with accuracy on account of disconnects between in vitro and in vivo preclinical data. To accurately estimate ƒₘCYP3A4 in human, an in vivo boost effect study was conducted using CYP3A4-humanized mouse model which showed a 33- to 56-fold exposure boost effect. Using a top-down approach, human ƒₘCYP3A4 for NVS123 was estimated to be very high and included in the human PBPK modeling to support subsequent clinical study design. The combined use of the in vivo boost study in CYP3A4-humanized mouse model mice along with PBPK modeling accurately predicted the clinical outcome and identified a significant NVS123 exposure boost (∼42-fold increase) with ritonavir.
Y1  - 2016
U6  - https://doi.org/doi.org/10.1016/j.xphs.2016.01.021
SN  - 0022-3549
VL  - Volume 105
IS  - Issue 4
SP  - 1398
EP  - 1404
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Scheer, Nico
A1  - Balimane, Praveen
A1  - Hayward, Michael D.
A1  - Buechel, Sandra
A1  - Kauselmann, Gunther
A1  - Wolf, C. Roland
T1  - Generation and Characterization of a Novel Multidrug Resistance Protein 2 Humanized Mouse Line
JF  - Drug Metabolism and Disposition
N2  - The multidrug resistance protein (MRP) 2 is predominantly expressed in liver, intestine, and kidney, where it plays an important role in the excretion of a range of drugs and their metabolites or endogenous compounds into bile, feces, and urine. Mrp knockout [Mrp2(−/−)] mice have been used recently to study the role of MRP2 in drug disposition. Here, we describe the first generation and initial characterization of a mouse line humanized for MRP2 (huMRP2), which is nulled for the mouse Mrp2 gene and expresses the human transporter in the organs and cell types where MRP2 is normally expressed. Analysis of the mRNA expression for selected cytochrome P450 and transporter genes revealed no major changes in huMRP2 mice compared with wild-type controls. We show that human MRP2 is able to compensate functionally for the loss of the mouse transporter as demonstrated by comparable bilirubin levels in the humanized mice and wild-type controls, in contrast to the hyperbilirubinemia phenotype that is observed in MRP2(−/−) mice. The huMRP2 mouse provides a model to study the role of the human transporter in drug disposition and in assessing the in vivo consequences of inhibiting this transporter by compounds interacting with human MRP2.
Y1  - 2012
U6  - https://doi.org/10.1124/dmd.112.047605
SN  - 1521-0111
VL  - 40
IS  - 11
SP  - 2212
EP  - 2218
PB  - ASPET
CY  - Bethesda, Md.
ER  - 
TY  - JOUR
A1  - Abulnaga, El-Hussiny
A1  - Pinkenburg, Olaf
A1  - Schiffels, Johannes
A1  - E-Refai, Ahmed
A1  - Buckel, Wolfgang
A1  - Selmer, Thorsten
T1  - Effect of an Oxygen-Tolerant Bifurcating Butyryl Coenzyme A Dehydrogenase/Electron-Transferring Flavoprotein Complex from Clostridium difficile on Butyrate Production in Escherichia coli
JF  - Journal of bacteriology
Y1  - 2013
SN  - 1098-5530 [E-Journal]
SN  - 0021-9193 [Print]
VL  - 195
IS  - 16
SP  - 3704
EP  - 3713
ER  - 
TY  - JOUR
A1  - Meyer-Stork, L. Sebastian
A1  - Höcker, Hartwig
A1  - Berndt, Heinz
T1  - Syntheses and reactions of urethanes of cellobiose and cellulose-containing uretdione groups
JF  - Journal of applied polymer science
Y1  - 1992
SN  - 1097-4628
VL  - 44
IS  - 6
SP  - 1043
EP  - 1049
ER  - 
TY  - GEN
A1  - Rothkranz, Berit
A1  - Krafft, Simone
A1  - Tippkötter, Nils
T1  - Media optimization for sustainable fuel production: How to produce biohydrogen from renewable resources with Thermotoga neapolitana
T2  - Chemie Ingenieur Technik
N2  - Hydrogen is playing an increasingly important role in research and politics as an energy carrier of the future. Since hydrogen has commonly been produced from methane by steam reforming, the need for climate-friendly, alternative production routes is emerging. In addition to electrolysis, fermentative routes for the production of so-called biohydrogen are "green" alternatives. The application of microorganisms offers the advantage of sustainable production from renewable resources using easily manageable technologies. In this project, the hyperthermophilic, anaerobic microorganism Thermotoga neapolitana is used for the productio nof biohydrogen from renewable resources. The enzymatically hydrolyzed resources were used in fermentation leading to yield coefficients of 1.8 mole H₂ per mole glucose when using hydrolyzed straw and ryegrass supplemented with medium, respectively. These results are similar to the hydrogen yields when using Thermotoga basal medium with glucose (TBGY) as control group. In order to minimize the supplementation of the hydrolysate and thus increase the economic efficiency of the process, the essential media components were identified. The experiments revealed NaCl, KCl, and glucose as essential components for cell growth as well as biohydrogen production. When excluding NaCl, a decrease of 96% in hydrogen production occured.
Y1  - 2022
U6  - https://doi.org/10.1002/cite.202255305
SN  - 0009-286X
SN  - 1522-2640 (eISSN)
N1  - ProcessNet and DECHEMA‐BioTechNet Jahrestagungen 2022 together with 13th ESBES Symposium 2022, 12. - 15. September 2022, Eurogress Aachen
VL  - 94
IS  - 9
SP  - 1298
EP  - 1299
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - GEN
A1  - Varriale, Ludovica
A1  - Kuka, Katrin
A1  - Tippkötter, Nils
A1  - Ulber, Roland
T1  - Use of a green biomass in a biorefinery platform
T2  - Chemie Ingenieur Technik
N2  - The emerging environmental issues due to the use of fossil resources are encouraging the exploration of new renewable resources. Biomasses are attracting more interest due to the low environmental impacts, low costs, and high availability on earth. In this scenario, green biorefineries are a promising platform in which green biomasses are used as feedstock. Grasses are mainly composed of cellulose and hemicellulose, and lignin is available in a small amount. In this work, a perennial ryegrass was used as feedstock to develop a green bio-refinery platform. Firstly, the grass was mechanically pretreated, thus obtaining a press juice and a press cake fraction. The press juice has high nutritional values and can be employed as part of fermentation media. The press cake can be employed as a substrate either in enzymatic hydrolysis or in solid-state fermentation. The overall aim of this work was to demonstrate different applications of both the liquid and the solid fractions. For this purpose, the filamentous fungus A. niger and the yeast Y. lipolythica were selected for their ability to produce citric acid. Finally, the possibility was assessed to use the press juice as part of fermentation media to cultivate S. cerevisiae and lactic acid bacteria for ethanol and lactic acid fermentation.
Y1  - 2022
U6  - https://doi.org/10.1002/cite.202255095
SN  - 0009-286X
SN  - 1522-2640 (eISSN)
N1  - ProcessNet and DECHEMA‐BioTechNet Jahrestagungen 2022 together with 13th ESBES Symposium 2022, 12. - 15. September 2022, Eurogress Aachen
VL  - 94
IS  - 9
SP  - 1299
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - BOOK
A1  - Wagemann, Kurt
A1  - Tippkötter, Nils
T1  - Biorefineries / Kurt Wagemann, Nils Tippkötter (editors)
T3  - Advances in biochemical engineering/biotechnology book series (ABE)
Y1  - 2019
SN  - 978-3-319-97117-9
SN  - 978-3-319-97119-3
U6  - https://doi.org/10.1007/978-3-319-97119-3
PB  - Springer
CY  - Cham (Switzerland)
ER  - 
TY  - GEN
A1  - Ross-Jones, J.
A1  - Teumer, T.
A1  - Capitain, C.
A1  - Tippkötter, Nils
A1  - Krause, M. J.
A1  - Methner, F.-J.
A1  - Rädle, M.
T1  - Analytical methods for in-line characterization of beer haze
T2  - Trends in Brewing
N2  - In most beers, producers strive to minimize haze to maximize visual appeal. To detect the formation of particulates, a measurement system for sub-micron particles is required. Beer haze is naturally occurring, composed of protein or polyphenol particles; in their early stage of growth their size is smaller than 2 µm. Microscopy analysis is time and resource intensive; alternatively, backscattering is an inexpensive option for detecting particle sizes of interest.
Y1  - 2018
N1  - Trends in Brewing, April 8 –12, 2018, Ghent, Belgium
ER  - 
TY  - CHAP
A1  - Schnabel, Eberhard
A1  - Berndt, Heinz
ED  - Nesvadba, H.
T1  - Zur selektive Abspaltbarkeit der t-Butyloxycarbonylgruppe
T2  - Peptides 1971 : proceedings of the Eleventh European Peptide Symposium, Vienna, Austria, April 1971
Y1  - 1973
SN  - 0-7204-4120-X
SP  - 69
EP  - 70
PB  - North-Holland Publ. [u.a.]
CY  - Amsterdam [u.a.]
ER  - 
TY  - JOUR
A1  - Zhantlessova, Sirina
A1  - Savitskaya, Irina
A1  - Kistaubayeva, Aida
A1  - Ignatova, Ludmila
A1  - Talipova, Aizhan
A1  - Pogrebnjak, Alexander
A1  - Digel, Ilya
T1  - Advanced “Green” prebiotic composite of bacterial cellulose/pullulan based on synthetic biology-powered microbial coculture strategy
JF  - Polymers
N2  - 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.
KW  - coculture
KW  - pullulan
KW  - exopolysaccharides
KW  - prebiotic
KW  - bacterial cellulose
Y1  - 2022
U6  - https://doi.org/10.3390/polym14153224
SN  - 2073-4360
N1  - This article belongs to the Special Issue "Cellulose Based Composites"
VL  - 14
IS  - 15
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Dallas, Shannon
A1  - Salphati, Laurent
A1  - Gomez-Zepeda, David
A1  - Wanek, Thomas
A1  - Chen, Liangfu
A1  - Chu, Xiaoyan
A1  - Kunta, Jeevan
A1  - Mezler, Mario
A1  - Menet, Marie-Claude
A1  - Chasseigneaux, Stephanie
A1  - Declèves, Xavier
A1  - Langer, Oliver
A1  - Pierre, Esaie
A1  - DiLoreto, Karen
A1  - Hoft, Carolin
A1  - Laplanche, Loic
A1  - Pang, Jodie
A1  - Pereira, Tony
A1  - Andonian, Clara
A1  - Simic, Damir
A1  - Rode, Anja
A1  - Yabut, Jocelyn
A1  - Zhang, Xiaolin
A1  - Scheer, Nico
T1  - Generation and Characterization of a Breast Cancer Resistance Protein Humanized Mouse Model
JF  - Molecular Pharmacology
N2  - Breast cancer resistance protein (BCRP) is expressed in various tissues, such as the gut, liver, kidney and blood brain barrier (BBB), where it mediates the unidirectional transport of substrates to the apical/luminal side of polarized cells. Thereby BCRP acts as an efflux pump, mediating the elimination or restricting the entry of endogenous compounds or xenobiotics into tissues and it plays important roles in drug disposition, efficacy and safety. Bcrp knockout mice (Bcrp−/−) have been used widely to study the role of this transporter in limiting intestinal absorption and brain penetration of substrate compounds. Here we describe the first generation and characterization of a mouse line humanized for BCRP (hBCRP), in which the mouse coding sequence from the start to stop codon was replaced with the corresponding human genomic region, such that the human transporter is expressed under control of the murine Bcrp promoter. We demonstrate robust human and loss of mouse BCRP/Bcrp mRNA and protein expression in the hBCRP mice and the absence of major compensatory changes in the expression of other genes involved in drug metabolism and disposition. Pharmacokinetic and brain distribution studies with several BCRP probe substrates confirmed the functional activity of the human transporter in these mice. Furthermore, we provide practical examples for the use of hBCRP mice to study drug-drug interactions (DDIs). The hBCRP mouse is a promising model to study the in vivo role of human BCRP in limiting absorption and BBB penetration of substrate compounds and to investigate clinically relevant DDIs involving BCRP.
Y1  - 2016
U6  - https://doi.org/10.1124/mol.115.102079
SN  - 1521-0111
VL  - 89
IS  - 5
SP  - 492
EP  - 504
PB  - ASPET
CY  - Bethesda, Md.
ER  - 
TY  - GEN
A1  - Duwe, A.
A1  - Schlegel, C.
A1  - Tippkötter, Nils
A1  - Ulber, Roland
T1  - Sequentielle Extraktion von Cellulose zur effizienten Nutzung der Stoffströme in der Holzbioraffinerie
T2  - Chemie Ingenieur Technik
N2  - In der Reihe der nachwachsenden Rohstoffe besitzt Holz als erneuerbare und umweltfreundliche Ressource ein großes Potenzial. Über 11 Mio. ha Holz, das laut der Fachagentur für nachwachsende Rohstoffe (FNR) auch für industrielle Zwecke genutzt werden kann, wuchsen im Jahr 2013 allein auf bundesdeutscher Fläche. 56,8 Mio. m³ jährlicher Holzeinschlag in den letzten zehn Jahren wurde zu knapp der Hälfte stofflich und der Rest energetisch verwertet. Im Rahmen dieser Arbeit konnte auf der Basis vom Holz der Buche, die nach Fichte und Kiefer die dritthäufigste Baumart in Deutschland ist und 15% der deutschen Waldfläche 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 flüssiger 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 Säuren 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 Stoffströme ohne Fällungsschritt und nachteiliger Verdünnung der Hemicellulose.
Y1  - 2014
U6  - https://doi.org/10.1002/cite.201450308
SN  - 0009-286X
SN  - 1522-2640 (eISSN)
N1  - ProcessNet-Jahrestagung 2014 und 31. DECHEMA-Jahrestagung der Biotechnologen, 30. September - 2. Oktober 2014, Eurogress Aachen
VL  - 86
IS  - 9
SP  - 1400
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Hahn, Thomas
A1  - Kelly, Svenja
A1  - Muffler, Kai
A1  - Tippkötter, Nils
A1  - Ulber, Roland
ED  - Hans-Jörg, Bart
ED  - Pilz, Stephan
T1  - Extraction of lignocellulose and algae for the production of bulk and fine chemicals
T2  - Industrial scale natural products extraction
Y1  - 2011
SN  - 978-3-527-32504-7 (Print)
SN  - 978-3-527-63512-2 (Online)
U6  - https://doi.org/10.1002/9783527635122
SP  - 221
EP  - 245
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Teumer, T.
A1  - Capitain, C.
A1  - Ross-Jones, J.
A1  - Tippkötter, Nils
A1  - Rädle, M.
A1  - Methner, F.-J.
T1  - In-line Haze Monitoring Using a Spectrally Resolved Back Scattering Sensor
JF  - BrewingScience
N2  - In the present work an optical sensor in combination with a spectrally resolved detection device for in-line particle-size-monitoring for quality control in beer production is presented. The principle relies on the size and wavelength dependent backscatter of growing particles in fluids. Measured interference structures of backscattered light are compared with calculated theoretical values, based on Mie-Theory, and fitted with a linear least square method to obtain particle size distributions. For this purpose, a broadband light source in combination with a process-CCD-spectrometer (charge ? coupled device spectrometer) and process adapted fiber optics are used. The goal is the development of an easy and flexible measurement device for in-line-monitoring of particle size. The presented device can be directly installed in product fill tubes or vessels, follows CIP- (cleaning in place) and removes the need of sample taking. A proof of concept and preliminary results, measuring protein precipitation, are presented.
Y1  - 2018
SN  - 1613-2041
VL  - 71
IS  - 5/6
SP  - 49
EP  - 55
PB  - Fachverlag Hans Carl
CY  - Nürnberg
ER  - 
TY  - JOUR
A1  - Rösch, C.
A1  - Kratz, F.
A1  - Hering, T.
A1  - Trautmann, S.
A1  - Umanskaya, N.
A1  - Tippkötter, Nils
A1  - Müller-Renno, C.M.
A1  - Ulber, Roland
A1  - Hannig, M.
A1  - Ziegler, C.
T1  - Albumin-lysozyme interactions: cooperative adsorption on titanium and enzymatic activity
JF  - Colloids and Surfaces B: Biointerfaces
N2  - The interplay of albumin (BSA) and lysozyme (LYZ) adsorbed simultaneously on titanium was analyzed by gel electrophoresis and BCA assay. It was found that BSA and lysozyme adsorb cooperatively. Additionally, the isoelectric point of the respective protein influences the adsorption. Also, the enzymatic activity of lysozyme and amylase (AMY) in mixtures with BSA was considered with respect to a possible influence of protein-protein interaction on enzyme activity. Indeed, an increase of lysozyme activity in the presence of BSA could be observed. In contrast, BSA does not influence the activity of amylase.
Y1  - 2016
U6  - https://doi.org/10.1016/j.colsurfb.2016.09.048
VL  - 149
IS  - 1
SP  - 115
EP  - 121
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Molinnus, Denise
A1  - Bäcker, Matthias
A1  - Siegert, Petra
A1  - Willenberg, H.
A1  - Poghossian, Arshak
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - Detection of Adrenaline Based on Substrate Recycling Amplification
JF  - Procedia Engineering
N2  - An amperometric enzyme biosensor has been applied for the detection of adrenaline. The adrenaline biosensor has been prepared by modification of an oxygen electrode with the enzyme laccase that operates at a broad pH range between pH 3.5 to pH 8. The enzyme molecules were immobilized via cross-linking with glutaraldehyde. The sensitivity of the developed adrenaline biosensor in different pH buffer solutions has been studied.
Y1  - 2015
U6  - https://doi.org/10.1016/j.proeng.2015.08.708
SN  - 1877-7058
N1  - Eurosensors 2015
VL  - 120
SP  - 540
EP  - 543
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Wagemann, Kurt
A1  - Tippkötter, Nils
T1  - Biorefineries: a short introduction
T2  - Biorefineries
N2  - The terms bioeconomy and biorefineries are used for a variety of processes and developments. This short introduction is intended to provide a delimitation and clarification of the terminology as well as a classification of current biorefinery concepts. The basic process diagrams of the most important biorefinery types are shown.
KW  - Bioeconomy
KW  - Biorefinery definitions
KW  - Introduction
KW  - Process schemes
KW  - Renewable resources
Y1  - 2018
SN  - 978-3-319-97117-9
SN  - 978-3-319-97119-3
U6  - https://doi.org/10.1007/10_2017_4
N1  - (Advances in Biochemical Engineering/Biotechnology book series ; Vol. 166)
SP  - 1
EP  - 11
PB  - Springer
CY  - Cham
ER  - 
TY  - JOUR
A1  - Wulfhorst, Helene
A1  - Duwe, Anna-Maria
A1  - Merseburg, Johannes
A1  - Tippkötter, Nils
T1  - Compositional analysis of pretreated (beech) wood using differential scanning calorimetry and multivariate data analysis
JF  - Tetrahedron
N2  - The composition of plant biomass varies depending on the feedstock and pre-treatment conditions and influences its processing in biorefineries. In order to ensure optimal process conditions, the quantitative proportion of the main polymeric components of the pre-treated biomass has to be determined. Current standard procedures for biomass compositional analysis are complex, the measurements are afflicted with errors and therefore often not comparable. Hence, new powerful analytical methods are urgently required to characterize biomass. In this contribution, Differential Scanning Calorimetry (DSC) was applied in combination with multivariate data analysis (MVA) to detect the cellulose content of the plant biomass pretreated by Liquid Hot Water (LHW) and Organosolv processes under various conditions. Unlike conventional techniques, the developed analytic method enables the accurate quantification of monosaccharide content of the plant biomass without any previous sample preparation. It is easy to handle and avoids errors in sample preparation.
Y1  - 2016
U6  - https://doi.org/10.1016/j.tet.2016.04.029
VL  - 72
IS  - 46
SP  - 7329
EP  - 7334
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wackwitz, B.
A1  - Bongaerts, Johannes
A1  - Goodman, S. D.
A1  - Unden, Gottfried
T1  - Growth phase-dependent regulation of nuoA-N expression in Escherichia coli K-12 by the Fis protein: upstream binding sites and bioenergetic significance
JF  - Molecular and general genetics : MGG
Y1  - 1999
SN  - 1617-4623 (E-Journal); 1617-4615 (Print)
VL  - Vol. 262
IS  - Iss. 4 - 5
SP  - 876
EP  - 883
ER  - 
TY  - JOUR
A1  - Tippkötter, Nils
A1  - Roikaew, W.
A1  - Ulber, Roland
T1  - Nitrate removal from whey concentrate with biotechnological regeneration of the waste water
JF  - European dairy magazine : EDM
Y1  - 2008
SN  - 0936-6318
IS  - 1
SP  - 30
EP  - 32
ER  - 
TY  - JOUR
A1  - Unden, G.
A1  - Becker, S.
A1  - Bongaerts, Johannes
A1  - Holighaus, G.
A1  - Schirawski, J.
A1  - Six, S.
T1  - O2-sensing and O2-dependent gene regulation in facultatively anaerobic bacteria
JF  - Archives of microbiology
Y1  - 1995
SN  - 1432-072X (E-Journal); 0003-9276 (Print); 0302-8933 (Print)
VL  - Vol. 164
IS  - Iss. 2
SP  - 81
EP  - 90
ER  - 
TY  - CHAP
A1  - Tippkötter, Nils
A1  - Stückmann, H.
A1  - Winkelmann, G.
A1  - Noack, U.
A1  - Beutel, S.
A1  - Scheper, T.
A1  - Ulber, Roland
T1  - Optimisation of antibody-labelling of gold colloids for their application in an immunchromatographic assay for microcystin-LR
T2  - European BioPerspectives : celebrating the 25th DECHEMA annual convention of biotechnologists ; 30 May - 1 June 2007, Cologne, Germany ; book of abstracts ; abstracts, poster programme
Y1  - 2007
SP  - 126
PB  - Dechema
CY  - Frankfurt am Main
ER  - 
TY  - JOUR
A1  - Tippkötter, Nils
A1  - Deterding, A.
A1  - Ulber, Roland
T1  - Determination of acetic acid in fermentation broth by gas-diffusion technique
JF  - Engineering in Life Sciences
N2  - Due to the interfering effects of acetic acid in many fermentation processes, a gas-diffusion technique was developed for the online determination of acetic acid. The measurements were accomplished with a flow diffusion analysis (FDA) unit from the TRACE Analytics GmbH, Braunschweig, Germany. The diffusion analysis is based on the UV-absorbance of acetic acid at 205 nm. The measurement was achieved by the separation of an acceptor and a carrier stream (acidified fermentation broth) using a gas permeable polytetrafluoroethylene (PTFE) membrane, whereby broth constituents that would otherwise disturb the UV-measurement of acetic acid, are held back efficiently. Merely, the fermentation by-products, e.g. formic acid, is capable of diffusing through the membrane. While formic acid can disturb the measurement, carbon dioxide does not absorb at 205 nm. The method operates with time-dependent sample enrichment. During the analysis, a small volume of the acceptor stream is stopped for a defined time interval in the acceptor chamber. During this period, the gaseous acetic acid diffuses through the membrane and is enriched in the acceptor chamber. Subsequently after the enrichment, the acceptor stream flows through a UV-detector. The intensity of the signal is proportional to the acetic acid concentration. Online measurements in bioreactors via a sterile filtration probe have been accomplished. A linear calibration in the range of 0.5–5.0 g/L acetic acid with a relative standard deviation of <5 % was obtained. A sampling rate of 8 samples per hour was possible. The system was applied for the determination of acetic acid in E. coli fermentation broth. The instrument is easy to clean, very user-friendly and does not require any toxic or expensive reagents.
Y1  - 2008
U6  - https://doi.org/10.1002/elsc.200820227
VL  - 8
IS  - 1, Special Issue: Technical Systems for the Use in Life Sciences
SP  - 62
EP  - 67
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Rakowski, D.
A1  - Poghossian, Arshak
A1  - Biselli, Manfred
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Chip-based amperometric enzyme sensor system for monitoring of bioprocesses by flow-injection analysis
JF  - Journal of Biotechnology
N2  - A microfluidic chip integrating amperometric enzyme sensors for the detection of glucose, glutamate and glutamine in cell-culture fermentation processes has been developed. The enzymes glucose oxidase, glutamate oxidase and glutaminase were immobilized by means of cross-linking with glutaraldehyde on platinum thin-film electrodes integrated within a microfluidic channel. The biosensor chip was coupled to a flow-injection analysis system for electrochemical characterization of the sensors. The sensors have been characterized in terms of sensitivity, linear working range and detection limit. The sensitivity evaluated from the respective peak areas was 1.47, 3.68 and 0.28 μAs/mM for the glucose, glutamate and glutamine sensor, respectively. The calibration curves were linear up to a concentration of 20 mM glucose and glutamine and up to 10 mM for glutamate. The lower detection limit amounted to be 0.05 mM for the glucose and glutamate sensor, respectively, and 0.1 mM for the glutamine sensor. Experiments in cell-culture medium have demonstrated a good correlation between the glutamate, glutamine and glucose concentrations measured with the chip-based biosensors in a differential-mode and the commercially available instrumentation. The obtained results demonstrate the feasibility of the realized microfluidic biosensor chip for monitoring of bioprocesses.
Y1  - 2013
U6  - https://doi.org/10.1016/j.jbiotec.2012.03.014
SN  - 0168-1656
VL  - 163
IS  - 4
SP  - 371
EP  - 376
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Tran, Quang Hon
A1  - Bongaerts, Johannes
A1  - Vlad, Dorina
A1  - Unden, Gottfried
T1  - Requirement for the proton-pumping NADH dehydrogenase I of Escherichia coli in respiration of NADH to fumarate and its bioenergetic implications
JF  - European journal of biochemistry
Y1  - 1997
SN  - 0014-2956
VL  - Vol. 244
IS  - Iss. 1
SP  - 155
EP  - 160
ER  - 
TY  - JOUR
A1  - Wiegand, Sandra
A1  - Voigt, Birgit
A1  - Albrecht, Dirk
A1  - Bongaerts, Johannes
A1  - Evers, Stefan
A1  - Hecker, Michael
A1  - Daniel, Rolf
A1  - Liesegang, Heiko
T1  - Fermentation stage-dependent adaptations of Bacillus licheniformis during enzyme production
JF  - Microbial Cell Factories
Y1  - 2013
U6  - https://doi.org/10.1186/1475-2859-12-120
SN  - 1475-2859
VL  - 12
SP  - 120
PB  - Biomed Central
CY  - London
ER  - 
TY  - CHAP
A1  - Tippkötter, Nils
A1  - Roikaew, W.
A1  - Ulber, Roland
T1  - An automated pilot plant for the bioengineering processing of concentrated whey
T2  - European BioPerspectives : in cooperation with BIOTECHNICA 2008 : 7 - 9 October 2008 Hannover, Germany ; book of abstracts ; abstracts, poster programme
Y1  - 2008
SP  - 98
PB  - Dechema
CY  - Frankfurt am Main
ER  - 
TY  - JOUR
A1  - Zientz, Evelyn
A1  - Bongaerts, Johannes
A1  - Unden, Gottfried
T1  - Fumarate regulation of gene expression in Escherichia coli by the DcuSR (dcuSR genes) two-component regulatory system
JF  - Journal of bacteriology
Y1  - 1998
SN  - 1098-5530 (E-Journal); 0021-9193 (Print)
VL  - Vol. 180
IS  - No. 20
SP  - 5421
EP  - 5425
ER  - 
TY  - JOUR
A1  - Roth, Jasmine
A1  - Tippkötter, Nils
T1  - Evaluation of lignocellulosic material for butanol production using enzymatic hydrolysate medium
JF  - Cellulose Chemistry and Technology
N2  - 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.
Y1  - 2016
VL  - 50
IS  - 3-4
SP  - 405
EP  - 410
PB  - Editura Academiei Romane
CY  - Bukarest
ER  - 
TY  - JOUR
A1  - Becht, Alexander
A1  - Schollmayer, Curd
A1  - Monakhova, Yulia
A1  - Holzgrabe, Ulrike
T1  - Tracing the origin of paracetamol tablets by near-infrared, mid-infrared, and nuclear magnetic resonance spectroscopy using principal component analysis and linear discriminant analysis
JF  - Analytical and Bioanalytical Chemistry
N2  - 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.
KW  - IR
KW  - Manufacturer
KW  - Linear discriminant analysis
KW  - Principal component analysis
Y1  - 2021
U6  - https://doi.org/10.1007/s00216-021-03249-z
SN  - 1618-2650
VL  - 413
SP  - 3107
EP  - 3118
PB  - Springer Nature
ER  - 
TY  - JOUR
A1  - Lindner, Simon
A1  - Burger, René
A1  - Rutledge, Douglas N.
A1  - Do, Xuan Tung
A1  - Rumpf, Jessica
A1  - Diehl, Bernd W. K.
A1  - Schulze, Margit
A1  - Monakhova, Yulia
T1  - Is the calibration transfer of multivariate calibration models between high- and low-field NMR instruments possible? A case study of lignin molecular weight
JF  - Analytical chemistry
N2  - 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.
Y1  - 2022
SN  - 1520-6882
U6  - https://doi.org/10.1021/acs.analchem.1c05125
VL  - 94
IS  - 9
SP  - 3997
EP  - 4004
PB  - ACS Publications
CY  - Washington, DC
ER  -