TY - GEN A1 - Böckelmann, Uta A1 - Janke, Andrea A1 - Kuhn, Ramona A1 - Neu, Thomas R. A1 - Wecke, Jörg A1 - Lawrence, John R. A1 - Szewzyk, Ulrich T1 - Bacterial extracellular DNA forming a defined network-like structure Y1 - 2006 ER - TY - GEN A1 - Guiot, Serge R. A1 - Kuhn, Ramona A1 - Lévesque, M. J. A1 - Cimpoia, Ruxandra T1 - Ultrastructure of a bioelectrolytic methanogenic/methanotrophic granular biofilm for the complete degradation of tetrachloroethylene in contaminated groundwater Y1 - 2007 ER - TY - GEN A1 - Guiot, Serge R. A1 - Cimpoia, Ruxandra A1 - Kuhn, Ramona A1 - Alaplantive, Aude T1 - Electrolytic Methanogenic-methanotropic coupling for Tetrachloroethylene Bioremediation: A Proof of Concept T2 - Environmental science & technology Y1 - 2008 SN - 0013-936X VL - 42 IS - 8 SP - 3011 EP - 3017 ER - TY - GEN A1 - Kuhn, Ramona A1 - Tóth, Elisabeth A1 - Geppert, Helmut A1 - Fischer, Thomas A1 - Martienssen, Marion T1 - Identification of the Complete Photodegradation Pathway of Ethylenediaminetetra(methylenephosphonic acid) in Aqueous Solution T2 - Clean - soil, air, water : a journal of sustainability and environmental safety N2 - This study aims at investigating the abiotic degradation pathway of ethylenediaminetetra(methylenephosphonic acid) (EDTMP) simulated applying UV irradiation. The degradation of EDTMP and formation of degradation products was determined using LC-MS and ³¹P-NMR. In the laboratory scale experiments, EDTMP was degraded within 30 min and the degradation products, iminodi(methylenephosphonic acid) (IDMP), ethylaminobis(methylenephosphonic acid) (EABMP), and amino- (methylenephosphonic acid) (AMPA), were simultaneously released. IDMP was the main degradation product of EDTMP. Therefore, we conclude that the initial cleavage of EDTMP is a heterolytically driven process, which starts the degradation process at the intramolecular C-N bond. In contrast, the main product of a possible homolytic C-C cleavage of methylaminobis(methylenephosphonic acid) could not be confirmed with either LC-MS or ³¹P-NMR. Additionally, there was no evidence for a primary attack on the C-P bond. All identified degradation products of EDTMP have been mineralized to carbon dioxide (CO₂). Three additional degradation products (M1, M2, and M3) have been found using the ³¹P-NMR analysis but have not yet been quantified using LC-MS. We assume that the unidentified degradation product M1 is related to m/z 312, M2 to m/z 341, and M3 to m/z 409. Thus we concluded that EDTMP undergoes photochemical conversion to IDMP, the main degradation product. EABMP and AMPA also accumulate, but in smaller amounts. All intermediates are further mineralized to CO₂. KW - EDTMP KW - LC-MS KW - 31P-NMR KW - Phosphonates KW - Photodegradation Y1 - 2017 U6 - https://doi.org/10.1002/clen.201500774 SN - 1863-0669 VL - 45 IS - 5 SP - 1 EP - 8 ER - TY - GEN A1 - Kuhn, Ramona A1 - Böllmann, Jörg A1 - Krahl, Kathrin A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion T1 - Comparison of ten different DNA extraction procedures with respect to their suitability for environmental samples T2 - Journal of Microbiological Methods N2 - DNA extraction for molecular biological applications usually requires target optimized extraction procedures depending on the origin of the samples. For environmental samples, a range of different procedures has been developed. We compared the applicability and efficiency of ten selected DNA extraction methods published in recent literature using four different environmental samples namely: activated sludge from a domestic wastewater treatment plant, river sediment, anaerobic digestion sludge and nitrifying enrichment culture. We assessed the suitability of the extraction procedures based on both DNA yield and quality. DNA quantification was performed by both ultra violet (UV) spectrophotometry and fluorescence spectrophotometry after staining with PicoGreen. In our study, DNA yields based on UV measurement were overestimated in most cases while DNA yields from fluorescence measurements correlated well with the sample load on agarose gels of crude DNA. The quality of the DNA extracts was determined by gel electrophoresis of crude DNA and PCR products from 16S rDNA with the universal primer set 27f/1525r. It was observed that gel electrophoresis of crude DNA was not always suitable to evaluate DNA integrity and purity since interfering background substances (e.g. humic substances) were not visible. Therefore, we strongly recommend examining the DNA quality of both crude DNA and 16S rDNA PCR products by gel electrophoresis when a new extraction method is established. Summarizing, we found four out of ten extraction procedures being applicable to all tested samples without noticeable restrictions. The procedure G (according to the standard method 432_10401 of the Lower Saxony State Office for Consumer Protection and Food Safety) had the broadest application range over procedure J (published by Wilson, 2001). These were followed by procedures F (Singka et al., 2012) and A (Bourrain et al., 1999). All four extraction procedures delivered reliable and reproducible crude DNA and PCR products. From an economical point of view, all procedures tested during this study were cheaper compared to commercial DNA extraction kits. KW - DNA extraction KW - DNA quantification KW - DNA yield KW - Environmental samples KW - Gel electrophoresis KW - PicoGreen Y1 - 2017 U6 - https://doi.org/10.1016/j.mimet.2017.10.007 SN - 0167-7012 VL - 143 SP - 78 EP - 86 ER - TY - GEN A1 - Kuhn, Ramona A1 - Böllmann, Jörg A1 - Krahl, Kathrin A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion T1 - Data on DNA gel sample load, gel electrophoresis, PCR and cost analysis T2 - Data in Brief N2 - The data presented in this article provide supporting information to the related research article “Comparison of ten different DNA extraction procedures with respect to their suitability for environmental samples” (revised manuscript submitted to J. Microbiol. Methods). In that article, we compared the suitability of ten selected DNA extraction methods based on DNA quality, purity, quantity and applicability to universal PCR. Here we provide the data on the specific DNA gel sample load, all unreported gel images of crude DNA and PCR results, and the complete cost analysis for all tested extraction procedures and in addition two commercial DNA extraction kits for soil and water. KW - Cost analysis KW - DNA sample load KW - Gel electrophoresis Y1 - 2018 U6 - https://doi.org/10.1016/j.dib.2017.11.082 SN - 2352-3409 VL - Vol. 16 SP - 732 EP - 751 ER - TY - GEN A1 - Domańska, Magdalena A1 - Kuhn, Ramona A1 - Łomotowski, Janusz A1 - Stańczyk, Ewa T1 - FISH method for identification of microbes in wastewater distribution systems T2 - Environmental Protection Engineering N2 - The FISH (fluorescence in situ hybridization) method is widely used to identify various types of cells. In comparison to cultivation-dependent methods, identification of microbes by FISH is easier and generally takes several hours. This paper presents a review of improvements to the FISH method, its advantages and disadvantages, as well as examples of applications. Particular consideration was given to the efficiency of microbes identification in samples taken from sewerage. The effectiveness of the method was confirmed by the results obtained in samples from the membrane bioreactor (MBR). Y1 - 2014 SN - 0324-8828 VL - 40 IS - 3 SP - 151 EP - 160 ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Bryant, Isaac Mbir A1 - Fischer, Thomas A1 - Liebsch, Stephan A1 - Martienssen, Marion T1 - The influence of selected bivalent metal ions on the photolysis of diethylenetriamine penta(methylenephosphonic acid) T2 - Chemosphere N2 - DTPMP is predominantly utilized as scale inhibitor. We investigated the reaction rates and degradation mechanism of DTPMP with and without addition of Fe²⁺, Mg²⁺ and Ca²⁺ by performing LC/MS and ³¹P-NMR analyses. DTPMP undergoes conversion with and without addition of bivalent metal ions. The initial cleavage of DTPMP is initiated at the C-N bond leading to release of IDMP as its major breakdown product. The release of smaller quantities of EABMP and AMPA confirmed the nucleophilic attack on the DTPMP amines. Oxidation of Fe²⁺ to Fe³⁺ during the initial 30 min indicated an intramolecular electron transfer changing the electron density distribution at the nitrogen centre, which increased the radical attack during UV irradiation. Independent of the fact that Fe acted as catalyst and Mg²⁺ and Ca²⁺ acted as reactants, we found no significant differences in their degradation mechanisms. However, the reaction rates were strongly affected by the addition of the bivalent metal ions as Fe²⁺ accelerated most DTPMP degradation followed by Mg²⁺ and Ca²⁺. The UV treatment without metal ion addition was four times slower compared with Fe²⁺ addition. We conclude that in environments rich in ferrous iron and/or at reduced redox potential, photolysis of DTPMP will be catalysed by iron and will lead to accumulation of IDMP, EABMP and AMPA and several other none-quantifiable breakdown products. KW - DTPMP KW - Ferrous ion KW - LC/MS KW - Phosphonates KW - Photolysis Y1 - 2018 U6 - https://doi.org/10.1016/j.chemosphere.2018.07.033 SN - 0045-6535 IS - 210 SP - 726 EP - 733 ER - TY - GEN A1 - Kuhn, Ramona A1 - Krahl, Kathrin A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion A1 - Böllmann, Jörg T1 - DNA-Extraktion aus mikrobiellen Umweltproben T2 - BioSpektrum Y1 - 2018 U6 - https://doi.org/10.1007/s12268-018-0963-0 SN - 1868-6249 SN - 0947-0867 VL - 24 IS - 6 SP - 596 EP - 598 ER - TY - CHAP A1 - Kuhn, Ramona A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion T1 - Unreactive Phosphorus - Organophosphonates (mini review) T2 - Organic compounds N2 - Phosphonates comprise a very large group of organophosphonates including aminophosphonates. Their main chemical feature leads to complexation of earth alkaline metals and transition metals (under stoichiometric). Therefore they are very often applied as complexing agents of detergents, as compounds of industrial cleaning products, or as antiscalants in cooling water systems and desalination processes. The high consumption of phosphonates within the past two decades leads to an increased discharge into the aquatic environment, of which the environmental risk is still uncertain. To date, there are several analytical methods published to determine phosphonates from environmental samples. However, no standard method has been defined until now. Different treatment technologies to break down phosphonates have been studied extensively such as photochemical degradation, chemical degradation and other advanced oxidation processes. The results obtained from those studies gained our chemical understanding with respect to possible implementation of such pre-treatment approaches in wastewater treatment, cooling water treatment and desalination process. The biological degradation of phosphonates has been studied for more than forty years. It was demonstrated that microorganisms are capable to breakdown the C-P bond with at least three different degradation pathways. KW - Phosphonates KW - Photodegradation KW - Biodegradation KW - Analytical detection Y1 - 2019 SN - 978-93-87500-41-9 PB - Open Access eBook CY - Las Vegas, USA ET - 1. Auflage ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Bryant, Isaac Mbir A1 - Fischer, Thomas A1 - Liebsch, Stephan A1 - Martienssen, Marion T1 - Rapid sample clean-up procedure for aminophosphonate determination by LC/MS analysis T2 - Talanta N2 - Aminophosphonates are commonly utilised for complexing bivalent ions such as calcium and magnesium. With regard to environmental samples, the analysis of these highly polar compounds is still challenging due to matrix effects and lacking analytical standard methods. We have recently developed a LC/MS method for common aminophosphonates without derivatisation. This LC/MS method delivers precise and accurate measurement for standard samples with very low concentration of cations disturbing the analysis. However, due to matrix effects this LC/MS method requires a sample clean-up being also applicable to natural water or wastewater samples. We developed and optimised a sample clean-up procedure applying strong cation exchange resin Dowex 50WX8. This clean-up allows a single LC/MS analysis of hydroxyethelidene(diphosphonic acid) (HEDP), aminotris(methylenephosphonic acid) (ATMP), ethylenediaminetetra(methyloenephosphonic acid) (EDTMP), diethylenetriaminepenta(methylenephosphonic acid) (DTPMP) and its major intermediates amino(methylphosphonic acid) (AMPA) and iminodi(methylenephosphonic acid) (IDMP). We compared different test conditions with six aminophosphonates in either ultra pure water or tap water. The latter was used to simulate cation concentrations typical for natural waters. To elute all aminophosphonate including AMPA, ammonium acetate addition was necessary. The addition of ammonium acetate was combinable with all tested aminophosphonates and provides high sample quality for LC/MS analysis. For acceptable recovery, the smallest aminophosphonate AMPA required the highest addition of ammonium acetate (1000 mg L-1) during the sample clean-up. Finally, the optimised clean-up procedure was successfully applied to identify and quantify phosphonates from an industrial wastewater sample. The sample clean-up procedure is simple, cheap, rapid and precise and can be further combined with solid phase extraction and more sensitive LC/MS methods. KW - Phosphontes Y1 - 2019 U6 - https://doi.org/10.1016/j.talanta.2019.120454 SN - 0039-9140 VL - 208 ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Bryant, Isaac Mbir A1 - Fischer, Thomas A1 - Liebsch, Stephan A1 - Martienssen, Marion T1 - Photodegradation of ethylenediaminetetra(methylenephosphonic acid) – The effect of the system configuration T2 - Journal of Photochemistry & Photobiology A: Chemistry N2 - Photodegradation of aminophosphonates such as ethylenediaminetetra(methylenephosphonic acid) (EDTMP) is recently assumed being the major degradation pathway in aquatic environments. Several photolysis studies were reported about EDTMP and possible breakdown products occurring in natural ecosystems. Reliable prediction of environmental photolysis of parent compounds and possible release of breakdown products requires different set-up conditions and varying the parameters influencing the photodegradation. We studied the influence of three different system configurations during UV degradation of EDTMP. These three configurations differed either in geometry and/or treated sample volumes. System 1 was equipped with a direct cooling jacket at the UV lamp. System 2 had the geometry of system 1 but there was no usage of a direct cooling jacket. System 3 was a gas-tight system with a larger sample volume. Using the chemical actinometer potassium ferrioxalate, we determined the highest photon flux for system 3 followed by system 2 and 1. In addition, we performed scavenger experiments with methanol and ascorbic acid in order to prove the dominating radical species. In system 1, the addition of methanol showed almost no effect while the ascorbic acid resulted in a reduction of 57.1% orthophosphate released. Therefore we conclude that in system 1 the radical-drive degradation of EDTMP is mainly based on superoxide radicals. In system 2 and 3 both radical species, i.e., hydroxyl radicals and superoxide radicals, contribute to the photodegradation of EDTMP. We determined different half-lives for EDTMP for the three different systems configurations. For system 1, the estimated half-life achieved was 14.09 ± 0.15 min. For system 2 and 3, the half-lives were almost similar and averaged 4.75 ± 0.05 min and 5.02 ± 0.20 min, respectively. Contrary to our assumption to also find the highest degradation rate for system 3, we found the highest degradation rate for system configuration 2 as a result of the differences in the construction and geometry of the three systems. Our findings lead us to recommend the three system configuration for different research purposes. Thus, we recommend system 1 for detailed studies on the degradation pathway of the parent compound and their breakdown products. System 2 is recommended as a suitable configuration for kinetic studies of the parent compound. And finally, we recommend the system configuration 3 for complete mass balances. The gas-tight system allows determining all soluble and gaseous compounds. KW - Phosphonates KW - Photodegradation KW - Photon flux KW - Scavenger KW - LC/MS KW - Actinometry Y1 - 2020 U6 - https://doi.org/10.1016/j.jphotochem.2019.112192 SN - 1010-6030 VL - 388 ER - TY - GEN A1 - Preuß, Volker A1 - Vornholt, Carsten A1 - Kuhn, Ramona A1 - Martienssen, Marion ED - Wessling, Matthias ED - Pinnekamp, Johannes T1 - Untersuchung zur Membrangängigkeit von Antiscalants T2 - 13. Aachener Tagung Wassertechnologie : Verfahren der Wasseraufbereitung und Abwasserbehandlung N2 - Aminophosphonate sind synthetisch hergestellte Komplexbildner, die kovalente C-P Bindungen aufweisen. Durch zusätzlich eingefügte Aminogruppen (NH2) komplexieren Amino-phosphonate besonders gut Metallionen, weshalb sie in einem sehr breiten Anwendungsspektum zum Einsatz kommen. So werden Phosphonate vielseitig als Haushalts- und Industriereiniger, aber auch als Komponenten von Kosmetika und in der Medizin verwendet. Des weiteren werden sie zur Kühlwasserkonditionierung, Stabilisierung von Peroxiden oder Bleichbädern und als Korrosionsinhibiter eingesetzt. Entsprechend der vielseitigen Anwendungsgebiete lag bereits in den früher 90igern des vergangenen Jahrhunderts die Gesamtproduktion an Phosphonaten in Europa bei über 11.000 Tonnen pro Jahr (Jaworska et al., 2002). Weltweit zeigen die Nutzung und der damit verbundene Bedarf an Phosphonaten einen immer weiter steigenden Trend. Dem entgegen steht der noch immer wenig untersuchte Verbleib und das chemische Verhalten von Phosphonaten in der Umwelt. Die gegenwärtig technisch eingesetzten Phosphonate ähneln in ihrer Struktur den bekannteren Aminocarboxylaten wie dem EDTA und NTA. Chemisch synthetisierte Phosphonate sind nur schwer biologisch abbaubar, weshalb zu einer kontinuierlichen Anreicherung in der aquatischen Umwelt kommen kann (Jaworska et al., 2002). Dies liegt unter anderem auch daran, dass Phosphonate als Phosphatersatz in großen Mengen in Waschmitteln enthalten sind und über das Abwasser in die Kläranlagen gelangen, wo sie nicht weiter biologisch abgebaut werden. Sie werden hauptsächlich durch Absorption an die Oberfläche vom Belebtschlamm aus den Abwasser entfernt. Nowack (2004) beschrieb die Toxizität von Phosphonaten in Kläranlagen als gering, verwies aber gleichzeitig darauf, dass aufgrund ihrer hohen Stabilität Phosphonate hemmend auf Proteasen und Syntheasen (Enzyme) von Mikroorganismen wirken. Der photochemische und biologische Abbau von dem Phosphonat EDTMP wurde eingehend untersucht, um dessen Umweltverhalten besser abschätzen zu können. Ziel der Untersuchungen war es den Abbauprozess zu entschlüsseln als Grundlage für die langfristige Entwicklung umweltverträglicher Aminophosphonatstrukturen. Der photochemische Abbau von EDTMP und die Bildung von Metaboliten konnte mittels LC-MS und 31P-NMR bereits aufgeklärt werden. So zeigt sich das EDTMP bereits nach wenigen Minuten im UV-Licht zerfällt und nicht mehr nachgewiesen werden kann. Als Hauptprodukt konnte das Phosphonat IDMP identifiziert werden. Als weitere Abbauprodukte konnten die Phosphonate EABMP und AMPA identifiziert werden. In allen Versuchen konnte nach 300 min UV-Behandlung mindestens 75% des Endprodukts CO2 nachgewiesen werden. Weitere drei maßgebliche Abbauprodukte wurden mit Hilfe der LC-MS gefunden. Deren chemische Struktur konnte bisher jedoch noch nicht eindeutig beschrieben werden. Im Anschluss an die UV-Experimente wurde ein Versuch mit Sonnenlicht simuliert. Insgesamt verlief der EDTMP-Abbau im Sonnenlicht wesentlich langsamer. Auch hier konnten wieder dieselben Abbauprodukte IDMP, EABMP und AMPA identifiziert werden. Zusätzlich traten auch die drei noch nicht eindeutig identifizierten Metaboliten von EDTMP auf. Aus den gewonnen Daten kann somit geschlussfolgert werden, dass EDTMP unter Einwirkung von UV-Licht abbaubar ist. Die Annahme, dass EDTMP und dessen Abbauprodukte langfristig zur Schädigung des aquatischen Ökosystems führt, kann somit nicht bestätigt werden. In weiteren Untersuchungen wurde der biologische Abbau von EDTMP und seiner photochemischen Abbauprodukten eingehend studiert. Für die Abbauversuche wurden die beiden Stämme Pseudomonas aeruginosa und Ochrobactrum sp. aus Boden isoliert. Es konnte gezeigt werden, dass sie 1mM EDTMP innerhalb von 35 Tagen zu mindestens 94% abbauen. Zusätzlich zum biologischen Abbau von EDTMP wurden auch die Verdopplungszeitung der beiden Stämme für EDTMP, IDMP, EABMP und AMAP ermittelt. Es zeigte sich, dass der Stamm P. aeruginosa für alle vier Phosphonate ein besseres wachstum zeigte als Ochrobactrum sp. Der Stamm P. aeruginosa erreichte für die Verstoffwechselung von EDTMP eine Verdopplungszeit von 10,1 Tagen, für IDMP 7,4 Tage, für EABMP 7,4 Tage und für AMPA 13,7 Tage. Der Stamm Ochrobactrum sp. erreichte für das Substrat EDTMP eine Verdopplungszeit von 11,8 Tagen, für IDMP 18,9 Tage, für EABMP 7,7 Tage und für AMPA 22,0 Tage. Offensichtlich war für beide Stämme der Abbau von AMPA der limitierende, aber nicht hemmende Schritt im biologischen Abbau. Somit kann geschlussfolgert werden, dass die Abbauprodukte der Photolyse auch biologisch abgebaut werden können. In weiteren Untersuchungen soll der biologische Abbau auf enzymatischer Ebene entschlüsselt werden. Die Identifizierung der Schüsselenzyme spielt hierbei eine wesentliche Rolle, um neuartige Phosphonatstrukturen herzuleiten, die auf der einen Seite ihre Funktionalität und Eigenschaften behalten, aber auf der anderen Seite eine erheblich verbesserte Bioverfügbarkeit aufweisen, so dass eine dauerhafte Akkumulation in der Umwelt und Folgebeeinträchtigungen minimiert ggf. ausgeschlossen werden können. KW - Antiscalant KW - Membranfiltration KW - Membrangängigkeit KW - Nanofiltration KW - Phosphonate KW - Umkehrosmose Y1 - 2019 SN - 978-3-95886-305-7 U6 - https://doi.org/10/35549368458 VL - 2019 SP - 117 EP - 123 PB - Verlagshaus Mainz GmbH Aachen CY - Aachen ET - 1. Auflage ER - TY - GEN A1 - Kuhn, Ramona A1 - Bryant, Isaac Mbir A1 - Jensch, Robert A1 - Liebsch, Stephan A1 - Martienssen, Marion T1 - Photolysis of hexamethylenediaminetetra(methylenephosphonic acid) (HDTMP) using manganese and hydrogen peroxide T2 - Emerging Contaminants N2 - Aminophosphonates such as hexamethylenediaminetreta(methylene phosphonic acid) (HDTMP) are categorised as persistent substances. They are commonly used as scale inhibitors in cooling water systems and desalination processes. After utilisation, they are often discharged into aquatic environment without pre-treatment. Advanced oxidation processes (AOP) are promising pre-treatments for industrial wastewater treatments. We investigated the photodegradation of HDTMP with or without addition of manganese (Mn2þ) and/or H2O2. Similar to results of our former photodegradation studies, we found that HDTMP also undergoes conversion with or without additives during the ultra violet (UV) irradiation. The reaction rate was most affected by the addition of H2O2, i.e. the HDTMP degradation was accelerated by a factor 3.85 compared with UV treatment without additives. The addition of Mn2þ accelerated the degradation of HDTMP only by a factor 1.53 compared with the UV treatment without additives. The combined addition of Mn2þ and H2O2 accelerated the HDTMP degradation by a factor 2.81. Interestingly, the initial cleavage is not initiated as expected at the CeN bond but at the CeP bond of the methyl carbon and the phosphorus of the methylenephosphonic acid group of HDTMP. This initial cleavage was independent whether the UV treatment was performed with or without additives. Therefore, we conclude that the degradation mechanism is similar independent of the four tested treatment conditions. We identified amino(methylenephosphonic acid) AMPA, dimethylamino(methylenephosphonic acid) DAMP and iminodi(methylenephosphonic acid) IDMP as the major breakdown products by performing LC/MS analyses. The major mineralisation products were ortho-phosphate, ammonium and carbon dioxide. The mass balances of unknown breakdown products KW - HDTMP KW - Hydrogen peroxide KW - Manganese KW - LC/MS KW - Phosphonates KW - Photolysis Y1 - 2019 U6 - https://doi.org/10.1016/j.emcon.2019.11.003 N1 - Die präsentierten Ergebnissen in diesem Artikel sind im Rahmen von zwei Abschlussarbeiten an der BTU erstellt worden. VL - 2020 IS - 6 SP - 10 EP - 19 ER - TY - GEN A1 - Preuß, Volker A1 - Vornholt, Carsten A1 - Kuhn, Ramona A1 - Martienssen, Marion ED - Pinnekamp, Johannes ED - Wessling, Matthias T1 - Untersuchung zur Membrangängikeit von Antiscalants T2 - Verfahren der Wasseraufbereitung und Abwasserbehandlung : 13. Aachener Tagung Wassertechnologie : Begleitbuch : 29.-30. Oktober 2019 Y1 - 2019 SN - 978-3-95886-305-7 SP - 117 EP - 123 PB - Aachener Verfahrenstechnik, RWTH Aachen ; Institut für Siedlungswasserwirtschaft, RWTH Aachen CY - Aachen ER - TY - GEN A1 - Kuhn, Ramona A1 - Vornholt, Carsten A1 - Preuß, Volker A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion T1 - Aminophosphonates in Nanofiltration and Reverse Osmosis Permeates T2 - Membranes N2 - Aminophosphonates such as aminotris(methylenephosphonic acid) (ATMP) are common constituents of antiscalants. In nanofiltration (NF) and reverse osmosis (RO) processes, ATMP prevents inorganic scaling leading to more stable membrane performance. So far, little attention has been paid to the possible permeation of aminophosphonates through NF and RO membranes. We have investigated the permeability of these membrane types for ATMP and its potential metabolites iminodi(methylenephosphonic acid) (IDMP) and amino(methylenephosphonic acid) (AMPA) with two different NF membranes (TS40 and TS80) and one RO membrane (ACM2) and three different water compositions (ultra-pure water, synthetic tap water and local tap water). We found traces of phosphonates in all investigated permeates. The highest phosphonate rejection occurred with local tap water for all three membranes investigated. Filtration experiments with a technical antiscalant formulation containing ATMP indicated similar trends of phosphonate permeability through all three membranes. We assume that the separation mechanisms of the membranes are the results of a very complex relationship between physico-chemical properties such as Donnan exclusion, feed pH, feed ionic strength and feed concentration, as well as solute–solute interactions. KW - ATMP KW - AMPA KW - phosphonates KW - nanofiltration KW - reverse osmosis KW - antiscalant KW - drinking water treatment Y1 - 2021 U6 - https://doi.org/10.3390/membranes11060446 SN - 2077-0375 VL - 11 IS - 6 SP - 1 EP - 16 ER - TY - GEN A1 - Kuhn, Ramona A1 - Bryant, Isaac Mbir A1 - Jensch, Robert A1 - Böllmann, Jörg T1 - Applications of Environmental Nanotechnologies in Remediation, Wastewater Treatment, Drinking Water Treatment, and Agriculture T2 - Applied Nano N2 - Today, nanotechnologies (NTs) are well established in both private households and commercial markets. NTs are fully accepted in several sectors, such as medicine and pharmacy, and in industries, such as chemistry, electricity, food production, military, and other commercial branches, due to their unique properties. With regard to the growing demands for environmental resources caused by the still-growing global population, the application of NTs is an extremely important new branch in the environmental sector, delivering several advantages. Our review provides a comprehensive overview of the current developments in environmental remediation, wastewater treatment, drinking water treatment, and agriculture. More specifically, in the section on environmental remediation, we review the application of NTs towards enhanced reductive dechlorination, removal of heavy metals and remediation of oil spills. In the section on wastewater treatment, we highlight developments in the adsorption of heavy metals and persistent substances, advanced photocatalytic degradation of common wastewater pollutants, and improvements in membrane filtration processes. In the section on drinking water treatment, we discuss applications for the enhanced disinfection of pathogens, removal of heavy metals, point-of-use treatments, and the removal of organic matter. In the final section, on agriculture, we provide an overview of precision farming and the current state of the art concerning nanofertilisers, nanopesticides, nanoherbicides, and nano(bio)sensors. Y1 - 2022 UR - https://www.mdpi.com/2673-3501/3/1/5 U6 - https://doi.org/10.3390/applnano3010005 SN - 2673-3501 VL - 3 IS - 1 SP - 54 EP - 90 ER - TY - CHAP A1 - Kuhn, Ramona A1 - Pollice, Alfieri A1 - Laera, Guiseppe A1 - Lipollis, Rosa A1 - Papa, Sergio ED - Lesjean, Boris T1 - Standard assays and metaproteomes as new approaches for functional characterization of membrane bioreactor biomass T2 - Membrane Technologies for Wastewater Treatment and Reuse, Proceedings der 2nd IWA National Young Water Professionals Conference in Berlin, 4.-6. Juni 2007 KW - Membrane bioreactors KW - biomass characterisation KW - EPS/SMP KW - metaproteomes Y1 - 2007 SN - 987-3-9811684-0-2 SP - 57 EP - 64 PB - IWA CY - Berlin ER - TY - GEN A1 - Kuhn, Ramona A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion T1 - Supplementary data on rapid sample clean-up procedure for aminophosphonate determination by LC/MS analysis T2 - MethodsX N2 - Minimising matrix effects through high sample purity is of major importance for LC/MS analysis. Here we provide supplementary data and protocols related to the article “Rapid sample clean-up procedure of aminophosphonates for LC/MS analysis”(revised article submitted to Talanta) [1] . It is demonstrated that the tested phosphonates iminodi(methylenephosphonic acid) (IDMP), hydroxyethelidene(diphosphonic acid) (HEDP), aminotris(methylenephosphonic acid) (ATMP), ethylenediaminetetra(methyloenephosphonic acid) (EDTMP) and diethylenetriaminepenta(methylenephosphonic acid) (DTPMP) dissolved in tap water are not detectable by LC/MS without sample clean-up. Only the smallest aminophosphonate amino(methylenephosphonic acid) (AMPA) was detectable but the recovery is decreased drastically. The optimised sample clean-up with cation exchange resin (CER) Dowex 50WX8 is described in detail and illustrated. The protocol is provided. The influence of the incubation time, addition of different ammonium acetate concentrations, different samples pHs and different water qualities is demonstrated and preferred clean- up conditions are recommended. Calibration results of all tested aminophosphonates are validated regarding limit of detection, limit of quantification, lower limit of quantification, absolute and relative process standard deviation. A final recommendation for the best clean-up condition for all six tested aminophosphonates is provided. KW - Phosphonates KW - LC/MS analysis KW - Cation Exchange Resin KW - Clean-up Y1 - 2020 U6 - https://doi.org/10.1016/j.mex.2020.100933 SN - 2215-0161 VL - 07 SP - 1 EP - 11 ER - TY - GEN A1 - Kuhn, Ramona A1 - Benndorf, Dirk A1 - Rapp, Erdmann A1 - Reichl, Udo A1 - Palese, Luigi Leonardo A1 - Pollice, Alfieri T1 - Metaproteome analysis of sewage sludge from membrane bioreactors T2 - Proteomics N2 - Microbial dynamics and enzymatic activities of activated sludge processes are not completely understood yet. A better understanding about the biology is indispensable for further process optimization. Since proteins play a key role as catalysts in sludge processes, a protocol for protein extraction and analysis by 2-D PAGE was established. It is based on phenol extraction of alkaline extracts and on a subsequent precipitation with ammonium sulphate. 2-D protein patterns obtained from different sludges collected from membrane bioreactors showed – besides common spots – significant differences. Selected proteins were identified with nano- HPLC-ESI-MS/MS. All membrane biological reactor (MBR) sludge samples investigated in this study contained elastase 3A, which implies that this human serine protease is a significant constituent of municipal wastewater. Although the identification of proteins from ammonia-oxidizing bacterium Nitrosomonas europaea was expected, the detection of a protein with homology to the marine bacterium Saprospira grandis in MBR1 was surprising. KW - De novo sequencing KW - Membrane bioreactor KW - metaproteomics KW - microbial communities KW - Microbiology KW - Protein extraction Y1 - 2011 U6 - https://doi.org/10.1002/pmic.201000590 SN - 1615-9861 VL - 11 IS - 13 SP - 2738 EP - 2744 ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Fischer, Thomas A1 - Keuler, Klaus A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion T1 - Sunlight Degradation of the Aminophosphonate Diethylenetriamine Penta-(Methylenephosphonic Acid) T2 - Solar N2 - Aminophosphonate diethylenetriamine penta(methylenephosphonic acid) (DTPMP) is a scale inhibitor commonly used in several industries. DTPMP is suspected to cause anthropogenic pollution through discharge into the aquatic environment. DTPMP is assumed to be degraded by sunlight radiation. We recently predicted a preliminary degradation pathway of DTPMP applyingUV treatment. Currently, we have not yet evidenced that DTPMP shows the same degradation pattern with natural sunlight. One major reason leads to the fact that the light spectrum emitted by UV lamps does not completely represent the natural sunlight spectrum, and the emitted UVB and UVA irradiation flux is much higher than for solar light. For that reason, the degradation pattern and kinetics might be different between artificial UV treatment and natural sunlight treatment. Here, we investigated whether DTPMP is degradable under natural sunlight radiation, and whether the degradation mechanisms determined through UV treatment are transferable to sunlight. We investigated five different treatment conditions, i.e., DTPMP degradation in direct or diffuse sunlight, in diffuse sunlight with addition of Ca2+ or Mg2+, and in diffuse sunlight with local TW. Our experiment was carried out from March 2021 to October 2021. We performed LC/MS analyses and measured the release of o-PO4 3  . DTPMP was degraded with all five treatment conditions. The fastest DTPMP degradation occurred in direct and diffuse sunlight without addition of bivalent cations. The addition of Ca2+ and Mg2+ resulted in inhibited degradation. Similar effects occurred for sunlight treatment with local TW. We evidenced different degradation mechanisms for DTPMP depending on the presence of alkaline earth metals as we previously proposed for UV-treated DTPMP. However, both degradation mechanisms of DTPMP belong to the same degradation pathway determined with UV treatment. Therefore, we conclude that DTPMP undergoes a similar degradation pathway in sunlight as compared to UV light. KW - Photochemistry Y1 - 2022 U6 - https://doi.org/10.3390/solar2020009 SN - 2673-9941 VL - 2 IS - 2 SP - 141 EP - 157 ER - TY - GEN A1 - Hertel, Robert A1 - Schöne, Kerstin A1 - Mittelstädt, Carolin A1 - Meißner, Janek A1 - Zschoche, Nick A1 - Collignon, Madeline A1 - Kohler, Christian A1 - Friedrich, Ines A1 - Schneider, Dominik A1 - Hoppert, Michael A1 - Kuhn, Ramona A1 - Schwedt, Inge A1 - Scholz, Patricia A1 - Poehlein, Anja A1 - Martienssen, Marion A1 - Ischebeck, Till A1 - Daniel, Rolf A1 - Commichau, Fabian M. T1 - Characterization of glyphosate-resistant Burkholderia anthina and Burkholderia cenocepacia isolates from a commercial Roundup® solution T2 - Environmental Microbiology Reports N2 - Roundup® is the brand name for herbicide solutions containing glyphosate, which specifically inhibits the 5-enolpyruvyl-shikimate-3-phosphate (EPSP) synthase of the shikimate pathway. The inhibition of the EPSP synthase causes plant death because EPSP is required for biosynthesis of aromatic amino acids. Glyphosate also inhibits the growth of archaea, bacteria, Apicomplexa, algae and fungi possessing an EPSP synthase. Here, we have characterized two glyphosate-resistant bacteria from a Roundup solution. Taxonomic classification revealed that the isolates 1CH1 and 2CH1 are Burkholderia anthina and Burkholderia cenocepacia strains respectively. Both isolates cannot utilize glyphosate as a source of phosphorus and synthesize glyphosate-sensitive EPSP synthase variants. Burkholderia. anthina 1CH1 and B. cenocepacia 2CH1 tolerate high levels of glyphosate because the herbicide is not taken up by the bacteria. Previously, it has been observed that the exposure of soil bacteria to herbicides like glyphosate promotes the development of antibiotic resistances. Antibiotic sensitivity testing revealed that the only the B. cenocepacia 2CH1 isolate showed increased resistance to a variety of antibiotics. Thus, the adaptation of B. anthina 1CH1 and B. cenocepacia 2CH1 to glyphosate did not generally increase the antibiotic resistance of both bacteria. However, our study confirms the genomic adaptability of bacteria belonging to the genus Burkholderia. Y1 - 2022 U6 - https://doi.org/10.1111/1758-2229.13022 SN - 1758-2229 VL - 14 IS - 1 SP - 70 EP - 84 ER - TY - GEN A1 - Hertel, Robert A1 - Gibhardt, Johannes A1 - Martienssen, Marion A1 - Kuhn, Ramona A1 - Commichau, Fabian M. T1 - Molecular mechanisms underlying glyphosate resistance in bacteria T2 - Environmental Microbiology N2 - Glyphosate is a nonselective herbicide that kills weeds and other plants competing with crops. Glyphosate specifically inhibits the 5-enolpyruvyl-shikimate-3-phosphate (EPSP) synthase, thereby depleting the cell of EPSP serving as a precursor for biosynthesis of aromatic amino acids. Glyphosate is considered to be toxicologically safe for animals and humans. Therefore, it became the most-important herbicide in agriculture. However, its intensive application in agriculture is a serious environmental issue because it may negatively affect the biodiversity. A few years after the discovery of the mode of action of glyphosate, it has been observed that bacteria evolve glyphosate resistance by acquiring mutations in the EPSP synthase gene, rendering the encoded enzyme less sensitive to the herbicide. The identification of glyphosate-resistant EPSP synthase variants paved the way for engineering crops tolerating increased amounts of the herbicide. This review intends to summarize the molecular mechanisms underlying glyphosate resistance in bacteria. Bacteria can evolve glyphosate resistance by (i) reducing glyphosate sensitivity or elevating production of the EPSP synthase, by (ii) degrading or (iii) detoxifying glyphosate and by (iv) decreasing the uptake or increasing the export of the herbicide. The variety of glyphosate resistance mechanisms illustrates the adaptability of bacteria to anthropogenic substances due to genomic alterations. Y1 - 2021 U6 - https://doi.org/10.1111/1462-2920.15534 SN - 1462-2920 SN - 1462-2912 VL - 23 IS - 6 SP - 2891 EP - 2905 ER -