42791
2018
2018
eng
16
8
19
article
Molecular Diversity Preservation International
Basel
1
2018-08-02
2018-08-02
--
Investigations of the Copper Peptide Hepcidin-25 by
LC-MS/MS and NMR⁺
Hepcidin-25 was identified as themain iron regulator in the human body, and it by binds to the sole iron-exporter ferroportin. Studies showed that the N-terminus of hepcidin is responsible for this interaction, the same N-terminus that encompasses a small copper(II) binding site known as the ATCUN (amino-terminal Cu(II)- and Ni(II)-binding) motif. Interestingly, this copper-binding property is largely ignored in most papers dealing with hepcidin-25. In this context, detailed investigations of the complex formed between hepcidin-25 and copper could reveal insight into its biological role. The present work focuses on metal-bound hepcidin-25 that can be considered the biologically active form. The first part is devoted to the reversed-phase chromatographic separation of copper-bound and copper-free hepcidin-25 achieved by applying basic mobile phases containing 0.1% ammonia. Further, mass spectrometry (tandemmass spectrometry (MS/MS), high-resolutionmass spectrometry (HRMS)) and nuclear magnetic resonance (NMR) spectroscopy were employed to characterize the copper-peptide. Lastly, a three-dimensional (3D)model of hepcidin-25with bound copper(II) is presented. The identification of metal complexes and potential isoforms and isomers, from which the latter usually are left undetected by mass spectrometry, led to the conclusion that complementary analytical methods are needed to characterize a peptide calibrant or referencematerial comprehensively. Quantitative nuclear magnetic resonance (qNMR), inductively-coupled plasma mass spectrometry (ICP-MS), ion-mobility spectrometry (IMS) and chiral amino acid analysis (AAA) should be considered among others.
International Journal of Molecular Sciences
10.3390/ijms19082271
1422-0067
1661-6596
2271
Universität Potsdam
PA 2018_39
472.51
<a href="http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-427926">Zweitveröffentlichung in der Schriftenreihe Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe ; 701</a>
CC-BY - Namensnennung 4.0 International
Ioana M. Abbas
Marija Vranic
Holger Hoffmann
Ahmed H. El-Khatib
María Montes-Bayón
Heiko Michael Möller
Michael G. Weller
eng
uncontrolled
hepcidin-25
eng
uncontrolled
copper
eng
uncontrolled
nickel
eng
uncontrolled
copper complex
eng
uncontrolled
ATCUN motif
eng
uncontrolled
metal complex
eng
uncontrolled
MS
eng
uncontrolled
NMR structure
eng
uncontrolled
metal peptide
eng
uncontrolled
metalloprotein
eng
uncontrolled
metallopeptide
eng
uncontrolled
isomerization
eng
uncontrolled
racemization
eng
uncontrolled
purity
eng
uncontrolled
reference material
Chemie und zugeordnete Wissenschaften
Biowissenschaften; Biologie
open_access
Institut für Chemie
Referiert
Publikationsfonds der Universität Potsdam
Open Access
63077
2022
2022
eng
17
18
article
Elsevier
Amsterdam
1
2022-06-01
2022-06-01
--
Advances in characteristics improvement of polymeric membranes/separators for zinc-air batteries
Zinc-air batteries (ZABs) are gaining popularity for a wide range of applications due to their high energy density, excellent safety, and environmental friendliness. A membrane/separator is a critical component of ZABs, with substantial implications for battery performance and stability, particularly in the case of a battery in solid state format, which has captured increased attention in recent years. In this review, recent advances as well as insight into the architecture of polymeric membrane/separators for ZABs including porous polymer separators (PPSs), gel polymer electrolytes (GPEs), solid polymer electrolytes (SPEs) and anion exchange membranes (AEMs) are discussed. The paper puts forward strategies to enhance stability, ionic conductivity, ionic selectivity, electrolyte storage capacity and mechanical properties for each type of polymeric membrane. In addition, the remaining major obstacles as well as the most potential avenues for future research are examined in detail.
Materials Today Sustainability
10.1016/j.mtsust.2022.100126
2589-2347
outputup:dataSource:WoS:2022
100126
WOS:000832975000006
Kheawhom, S (corresponding author), Chulalongkorn Univ, Fac Engn, Dept Chem Engn, Bangkok 10330, Thailand.; Lu, Y (corresponding author), Helmholtz Zentrum Berlin Mat & Energie, Dept Electrochem Energy Storage, Hahn Meitner Pl 1, Berlin, Germany.; Kheawhom, S (corresponding author), Chulalongkorn Univ, Res Unit Adv Mat Energy Storage, Bangkok 10330, Thailand.; Kheawhom, S (corresponding author), Chulalongkorn Univ, Biocircular Green Econ Technol & Engn Ctr BCGeTEC, Fac Engn, Bangkok 10330, Thailand.; Lu, Y (corresponding author), Univ Potsdam, Inst Chem, Potsdam, Germany., soorathep.k@chula.ac.th; yan.lu@helmholtz-berlin.de
Program Unit for Human Resources & Institutional Development, Research; and Innovation [B16F640166]; National Science and Technology Development; Agency [P-20-50281]; Energy Storage Cluster, Chulalongkorn University;; Chulalongkorn Academic Advancement into its 2nd Century Project for; Postdoctoral Fellowship
Lu, Yan
2024-03-27T12:15:29+00:00
sword
importub
filename=package.tar
c4352f9538c25cf7f0155bb0871fbcd8
false
true
Ali Abbasi
Yaolin Xu
Ramin Khezri
Mohammad Etesami
C. Lin
Soorathep Kheawhom
Yan Lu
eng
uncontrolled
Ionic selectivity
eng
uncontrolled
Ionic conductivity
eng
uncontrolled
Gel polymer
eng
uncontrolled
Ion exchange
eng
uncontrolled
Porous
eng
uncontrolled
polymer
Chemie und zugeordnete Wissenschaften
Institut für Chemie
Referiert
Import
37612
2014
2014
eng
67
73
7
9
article
Elsevier
Amsterdam
1
--
--
--
A xanthone and a phenylanthraquinone from the roots of Bulbine frutescens, and the revision of six seco-anthraquinones into xanthones
Phytochemical investigation of the dichloromethane/methanol (1:1) extract of the roots of Bulbine frutescens led to the isolation of a new xanthone, 8-hydroxy-6-methylxanthone-1-carboxylic acid (1) and a new phenylanthraquinone, 6',8-O-dimethylknipholone (2) along with six known compounds. The structures were elucidated on the basis of NMR and MS spectral data analyses. The structure of compound 1 was confirmed through X-ray crystallography which was then used as a reference to propose the revision of the structures of six seco-anthraquinones into xanthones. The isolated compounds were evaluated for cytotoxicity against human cervix carcinoma KB-3-1 cells with the phenylanthraquinone knipholone being the most active (IC50 = 0.43 mu M). Two semi-synthetic knipholone derivatives, knipholone Mannich base and knipholone-1,3-oxazine, were prepared and tested for cytotoxic activity; both showed moderate activities (IC50 value of 1.89 and 2.50 mu M, respectively). (C) 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.
Phytochemistry letters
10.1016/j.phytol.2014.04.004
1874-3900
1876-7486
wos:2014
WOS:000340884100013
Yenesew, A (reprint author), Univ Nairobi, Dept Chem, POB 30197-00100, Nairobi, Kenya., ayenesew@uonbi.ac.ke
German Academic Exchange Service (DAAD) for the scholarship through
Natural Product Research Network of Eastern and Central Africa
(NAPRECA); ISP (Sweden) [KEN-02]
Negera Abdissa
Matthias Heydenreich
Jacob O. Midiwo
Albert Ndakala
Zsuzsanna Majer
Beate Neumann
Hans-Georg Stammler
Norbert Sewald
Abiy Yenesew
eng
uncontrolled
Bulbine frutescens
eng
uncontrolled
Xanthone
eng
uncontrolled
seco-Anthraquinone
eng
uncontrolled
Phenylanthraquinone
eng
uncontrolled
Cytotoxicity
eng
uncontrolled
Structure revision
Institut für Chemie
Referiert
35060
2013
2013
eng
241
245
5
2
6
article
Elsevier
Amsterdam
1
--
--
--
Knipholone cyclooxanthrone and an anthraquinone dimer with antiplasmodial activities from the roots of Kniphofia foliosa
A new phenylanthrone, named knipholone cyclooxanthrone and a dimeric anthraquinone, 10-methoxy-10,7'-(chrysophanol anthrone)-chrysophanol were isolated from the roots of Kniphofia foliosa together with the rare naphthalene glycoside, dianellin. The structures were determined by NMR and mass spectroscopic techniques. The compounds showed antiplasmodial activities against the chloroquine-resistant (W2) and chloroquine-sensitive (D6) strains of Plasmodium falciparum with 10-methoxy-10,7'-(chrysophanol anthrone)-chrysophanol being the most active with IC50 values of 1.17 +/- 0.12 and 4.07 +/- 1.54 mu g/ml, respectively.
Phytochemistry letters
10.1016/j.phytol.2013.02.005
1874-3900
wos:2011-2013
WOS:000318271400019
Yenesew, A (reprint author), Univ Nairobi, Dept Chem, POB 30197-00100, Nairobi, Kenya., ayenesew@uonbi.ac.ke
German Academic Exchange Service (DAAD) through Natural Product Research
Network of Eastern and Central Africa (NAPRECA); International Science
Program (ISP, Sweden) [KEN-02]
Negera Abdissa
Martha Induli
Hoseah M. Akala
Matthias Heydenreich
Jacob O. Midiwo
Albert Ndakala
Abiy Yenesew
eng
uncontrolled
Kniphofia foliosa
eng
uncontrolled
Asphodelaceae
eng
uncontrolled
Roots
eng
uncontrolled
Anthraquinone
eng
uncontrolled
Knipholone cyclooxanthrone
eng
uncontrolled
10-Methoxy-10,7 '-(chrysophanol anthrone)-chrysophanol
eng
uncontrolled
Dianellin
eng
uncontrolled
Malaria
Institut für Chemie
Referiert
62405
2022
2022
eng
939
947
9
7
6
article
Royal Society of Chemistry
Cambridge
1
2022-02-22
2022-02-22
--
Ionic guest in ionic host
Ionosilica ionogels, i.e. composites consisting of an ionic liquid (IL) guest confined in an ionosilica host matrix, were synthesized via a non-hydrolytic sol-gel procedure from a tris-trialcoxysilylated amine precursor using the IL [BMIM]NTf2 as solvent. Various ionosilica ionogels were prepared starting from variable volumes of IL in the presence of formic acid. The resulting brittle and nearly colourless monoliths are composed of different amounts of IL guests confined in an ionosilica host as evidenced via thermogravimetric analysis, FT-IR, and C-13 CP-MAS solid-state NMR spectroscopy. In the following, we focused on confinement effects between the ionic host and guest. Special host-guest interactions between the IL guest and the ionosilica host were evidenced by H-1 solid-state NMR, Raman spectroscopy, and broadband dielectric spectroscopy (BDS) measurements. The three techniques indicate a strongly reduced ion mobility in the ionosilica ionogel composites containing small volume fractions of confined IL, compared to conventional silica-based ionogels. We conclude that the ionic ionosilica host stabilizes an IL layer on the host surface; this then results in a strongly reduced ion mobility compared to conventional silica hosts. The ion mobility progressively increases for systems containing higher volume fractions of IL and finally reaches the values observed in conventional silica based ionogels. These results therefore point towards strong interactions and confinement effects between the ionic host and the ionic guest on the ionosilica surface. Furthermore, this approach allows confining high volume fractions of IL into self-standing monoliths while preserving high ionic conductivity. These effects may be of interest in domains where IL phases must be anchored on solid supports to avoid leaching or IL spilling, e.g., in catalysis, in gas separation/sequestration devices or for the elaboration of solid electrolytes for (lithium-ion) batteries and supercapacitors.
Materials chemistry frontiers
ionosilica ionogel composites via ionic liquid confinement in ionosilica supports
10.1039/d2qm00021k
2052-1537
outputup:dataSource:WoS:2022
WOS:000762380300001
Hesemann, P; Mehdi, A (corresponding author), Univ Montpellier, ENSCM, CNRS, ICGM, Montpellier, France., peter.hesemann@umontpellier.fr
Hesemann, Peter
2024-02-01T06:54:03+00:00
sword
importub
filename=package.tar
88e7ece85f16cf9aa4407341bc57ae2b
2867881-3
Nicole Abdou
Bruno Alonso
Nicolas Brun
Perine Landois
Andreas Taubert
Peter Hesemann
Ahmad Mehdi
Chemie und zugeordnete Wissenschaften
Institut für Chemie
Referiert
Import
27297
1995
1995
eng
article
1
--
--
--
Emodine and emodinanthrone rhamnoside acetates from fruits of rhamnus prinoides
0031-9422
allegro:1991-2014
10082496
Phytochemistry. - ISSN 0031-9422. - 39 (1995), 6, S. 1411 - 1414
Berhanu M. Abegaz
Martin G. Peter
Institut für Chemie
Institut für Organische Chemie und Strukturanalytik
46089
2017
2017
eng
5640
5649
10
article
Wiley-VCH
Weinheim
1
--
--
--
Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
European journal of inorganic chemistry : a journal of ChemPubSoc Europe
10.1002/ejic.201700826
1434-1948
1099-0682
wos:2017
WOS:000418925900003
Taubert, A (reprint author), Univ Potsdam, Inst Chem, D-14476 Potsdam, Germany., ataubert@uni-potsdam.de
Deutsche Forschungsgemeinschaft (DFG) SPP1708 Grant [TA571/13-1]; University of Potsdam
importub
2020-04-19T22:34:01+00:00
filename=package.tar
fbfabf8f6bfc7c2f01dc87e268ac2b03
Ahed Abouserie
Kerstin Zehbe
Philipp Metzner
Alexandra Kelling
Christina Günter
Uwe Schilde
Peter Strauch
Thomas Körzdörfer
Andreas Taubert
eng
uncontrolled
Ionic liquids
eng
uncontrolled
Alkylpyridinium salts
eng
uncontrolled
Structure elucidation
eng
uncontrolled
Phase transitions
Institut für Chemie
Institut für Geowissenschaften
Referiert
Institut für Erd- und Umweltwissenschaften
Import
45922
2017
2017
eng
5640
5649
10
article
Wiley-VCH
Weinheim
1
--
--
--
Alkylpyridinium Tetrahalidometallate Ionic Liquids and Ionic Liquid Crystals: Insights into the Origin of Their Phase Behavior
Six N-alkylpyridinium salts [CnPy](2)[MCl4] (n = 4 or 12 and M = Co, Cu, Zn) were synthesized, and their structure and thermal properties were studied. The [C4Py](2)[MCl4] compounds are monoclinic and crystallize in the space group P2(1)/n. The crystals of the longer chain analogues [C12Py](2)[MCl4] are triclinic and crystallize in the space group P (1) over bar. Above the melting temperature, all compounds are ionic liquids (ILs). The derivatives with the longer C12 chain exhibit liquid crystallinity and the shorter chain compounds only show a melting transition. Consistent with single-crystal analysis, electron paramagnetic resonance spectroscopy suggests that the [CuCl4](2-) ions in the Cu-based ILs have a distorted tetrahedral geometry.
European journal of inorganic chemistry : a journal of ChemPubSoc Europe
10.1002/ejic.201700826
1434-1948
1099-0682
wos:2017
WOS:000418925900003
Taubert, A (reprint author), Univ Potsdam, Inst Chem, D-14476 Potsdam, Germany., ataubert@uni-potsdam.de
Deutsche Forschungsgemeinschaft (DFG) SPP1708 Grant [TA571/13-1]; University of Potsdam
importub
2020-03-24T18:34:10+00:00
filename=package.tar
00392e77f607fcfeee5c17ec027a6884
Ahed Abouserie
Kerstin Zehbe
Philipp Metzner
Alexandra Kelling
Christina Günter
Uwe Schilde
Peter Strauch
Thomas Körzdörfer
Andreas Taubert
eng
uncontrolled
Ionic liquids
eng
uncontrolled
Alkylpyridinium salts
eng
uncontrolled
Structure elucidation
eng
uncontrolled
Phase transitions
Institut für Chemie
Institut für Geowissenschaften
Referiert
Institut für Erd- und Umweltwissenschaften
Import
36855
2011
2011
eng
4
17
5
article
BioMed Central
London
1
--
--
--
Synthesis and crystal structure of 1,4,10,13-tetraoxa-7,16-diazoniumcyclo-octadecane bis(4-chloro-2-methyl-phenoxyacetate)
The title compound was prepared by the reaction of 1,4,10,13-tetraoxa-7,16-diazacyclo-octadecane with 4-chloro-2-methyl-phenoxyacetic acid in a ratio of 1:2. The structure has been proved by the data of elemental analysis, IR spectroscopy, NMR ((1)H, (13)C) technique and by X-ray diffraction analysis. Intermolecular hydrogen bonds between the azonium protons and oxygen atoms of the carboxylate groups were found. Immunoactive properties of the title compound have been screened. The compound has the ability to suppress spontaneous and Con A-stimulated cell proliferation in vitro and therefore can be considered as immunodepressant.
Chemistry central journal
10.1186/1752-153X-5-23
1752-153X
wos:2011-2013
23
WOS:000291054000001
Schilde, U (reprint author), Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany., us@chem.uni-potsdam.de
Sergey N. Adamovich
Anna N. Mirskova
Rudolf G. Mirskov
Uwe Schilde
Institut für Chemie
Referiert
Open Access
54773
2017
2017
eng
56
63
8
130
article
Elsevier
Amsterdam
1
2017-04-28
2017-04-28
--
Using absorption and reduced scattering coefficients for non-destructive analyses of fruit flesh firmness and soluble solids content in pear
Quality attributes of fruit determine its acceptability by the retailer and consumer. The objective of this work was to investigate the potential of absorption (μa) and reduced scattering (μs’) coefficients of European pear to analyze its fruit flesh firmness and soluble solids content (SSC). The absolute reference values, μa* (cm−1) and μs’* (cm−1), of pear were invasively measured, employing multi-spectral photon density wave (PDW) spectroscopy at preselected wavelengths of 515, 690, and 940 nm considering two batches of unripe and overripe fruit. On eight measuring dates during fruit development, μa and μs’ were analyzed non-destructively by means of laser light backscattering imaging (LLBI) at similar wavelengths of 532, 660, and 830 nm by means of fitting according to Farrell’s diffusion theory, using fix reference values of either μa* or μs’*. Both, the μa* and the μa as well as μs’* and μs’ showed similar trends. Considering the non-destructively measured data during fruit development, μa at 660 nm decreased 91 till 141 days after full bloom (dafb) from 1.49 cm−1 to 0.74 cm−1 due to chlorophyll degradation. At 830 nm, μa only slightly decreased from 0.41 cm−1 to 0.35 cm−1. The μs’ at all wavelengths revealed a decreasing trend as the fruit developed. The difference measured at 532 nm was most pronounced decreasing from 24 cm−1 to 10 cm−1, while at 660 nm and 830 nm values decreased from 15 cm−1 to 13 cm−1 and from 10 cm−1 to 8 cm−1, respectively. When building calibration models with partial least-squares regression analysis on the optical properties for non-destructive analysis of the fruit SSC, μa at 532 nm and 830 nm resulted in a correlation coefficient of R = 0.66, however, showing high measuring uncertainty. The combination of all three wavelengths gave an enhanced, encouraging R = 0.89 for firmness analysis using μs’ in the freshly picked fruit.
Postharvest Biology and Technology
10.1016/j.postharvbio.2017.04.004
0925-5214
1873-2356
wos:2017
WOS:000401880200007
Zude-Sasse, M (reprint author), Leibniz Inst Agr Engn & Bioecon ATB, Dept Hort Engn, D-14469 Potsdam, Germany., mzude@atb-potsdam.de
German Federal Ministry of Education and Research [03Z22AN12]; German Federal State of Brandenburg; Ministry of Science, Technology and Innovation, Malaysia under a Science Fund research grant [5450728]
2022-04-13T10:25:51+00:00
sword
importub
filename=package.tar
09549e5033487bf6a372c211634cb7c8
false
true
Segun Emmanuel Adebayo
Norhashila Hashim
Roland Hass
Oliver Reich
Christian Regen
Marvin Münzberg
Khalina Abdan
Marsyita Hanafi
Manuela Zude-Sasse
eng
uncontrolled
Absorption
eng
uncontrolled
Non-destructive
eng
uncontrolled
Pear
eng
uncontrolled
Quality
eng
uncontrolled
Scattering
Chemie und zugeordnete Wissenschaften
Institut für Chemie
Referiert
Import
Green Open-Access