TY - JOUR AU - Michalke, B. AU - Garcia-Barrera, T.* AU - Nischwitz, V.* AU - Solovyev, N.* C1 - 66753 C2 - 53289 TI - Editorial: New analytical method developments for metallomics research. JO - Front. Chem. VL - 10 PY - 2022 SN - 2296-2646 ER - TY - JOUR AB - Parkinson´s disease progression is linked to iron redox status homeostasis via reactive oxygen species (ROS) formation, and lipids are the primary targets of ROS. The determination of iron redox status in vivo is challenging and requires specific extraction methods, which are so far tedious and very time-consuming. We demonstrated a novel, faster, and less laborious extraction method using the chelator ethylene glycol l-bis(β-aminoethyl ether)-N,N,N',N'-tetra acetic acid (EGTA) as a stabilizing agent and synthetic quartz beads for homogenization under an argon atmosphere. Additionally, we combined the metal extraction with a well-established lipid extraction protocol using methyl-tert-butyl ether (MTBE) to avoid the problems of lipid precipitation in frozen samples and to determine lipid profiles and metal species from the same batch. The nonextractable matrix, such as the debris, is removed by centrifugation and digested to determine the total metal content of the sample as well. Lipid profiling using RP-LC-MS demonstrated high accordance of the modified extraction method to the reference method, and the organic solvent does not affect the iron redox status equilibrium. Furthermore, rigorous testing demonstrated the stability of the iron redox status equilibrium during the extraction process, secured by complexation, inert atmosphere, fast preparation, and immediately deep frozen extracts. AU - Blume, B. AU - Witting, M. AU - Schmitt-Kopplin, P. AU - Michalke, B. C1 - 63867 C2 - 51679 CY - Avenue Du Tribunal Federal 34, Lausanne, Ch-1015, Switzerland TI - Novel extraction method for combined lipid and metal speciation from Caenorhabditis elegans with focus on iron redox status and lipid profiling. JO - Front. Chem. VL - 9 PB - Frontiers Media Sa PY - 2021 SN - 2296-2646 ER - TY - JOUR AB - Here, we report a non-targeted analytical approach to investigate the influence of different starch sources on the metabolic signature in the final beer product. An extensive sample set of commercial beers brewed with barley, wheat, corn and/or rice were analyzed by both direct infusion Fourier transform ion cyclotron mass spectrometry (DI-FTICR MS, 400 samples) and UPLC-ToF-MS (100 samples). By its unrivaled mass resolution and accuracy, DI-FTICR-MS was able to uncover the compositional space of both polar and non-polar metabolites that can be traced back to the use of different starch sources. Reversed phase UPLC-ToF-MS was used to access information about molecular structures (MS2-fragmentation spectra) and isomeric separation, with a focus on less polar compounds. Both analytical approaches were able to achieve a clear statistical differentiation (OPLS-DA) of beer samples and reveal metabolic profiles according to the starch source. A mass difference network analysis, applied to the exact marker masses resolved by FTICR, showed a network of potential secondary metabolites specific to wheat, corn and rice. By MS2-similarity networks, database and literature search, we were able to identify metabolites and compound classes significant for the use of the different starch sources. Those were also found in the corresponding brewing raw materials, confirming the potential of our approach for quality control and monitoring. Our results also include the identification of the aspartic acid-conjugate of N-β-D-glucopyranosyl-indole-3-acetic acid as a potential marker for the use of rice in the brewing industry regarding quality control and food inspection purposes. AU - Pieczonka, S.A.* AU - Paravicini, S.* AU - Rychlik, M.* AU - Schmitt-Kopplin, P. C1 - 62754 C2 - 51046 CY - Avenue Du Tribunal Federal 34, Lausanne, Ch-1015, Switzerland TI - On the trail of the German purity law: Distinguishing the metabolic signatures of wheat, corn and rice in beer. JO - Front. Chem. VL - 9 PB - Frontiers Media Sa PY - 2021 SN - 2296-2646 ER - TY - JOUR AB - Neuronal iron dyshomeostasis occurs in multiple neurodegenerative diseases. Changes in the Fe(II)/Fe(III) ratio toward Fe(II) is closely related to oxidative stress, lipid peroxidation, and represents a hallmark feature of ferroptosis. In particular for body fluids, like cerebrospinal fluid (CSF), reliable quantitative methods for Fe(II)/(III) redox-speciation analysis are needed to better assess the risk of Fe(II)-mediated damage in brain tissue. Currently in the field of metallomics, the most direct method to analyze both iron species is via LC-ICP-MS. However, this Fe(II)/(III) speciation analysis method suffers from several limitations. Here, we describe a unique method using capillary electrophoresis (CE)-ICP-MS for quantitative Fe(II)/(III) speciation analysis that can be applied for cell lysates and biofluid samples. Compared to LC, CE offers various advantages: (1) Capillaries have no stationary phase and do not depend on batch identity of stationary phases; (2) Replacement of aged or blocked capillaries is quick with no performance change; (3) Purge steps are effective and short; (4) Short sample analysis time. The final method employed 20 mM HCl as background electrolyte and a separation voltage of +25 kV. In contrary to the LC-method, no complexation of Fe-species with pyridine dicarboxylic acid (PDCA) was applied, since it hampered separation. Peak shapes and concentration detection limits were improved by combined conductivity-pH-stacking achieving 3 μg/L detection limit (3σ) at 13 nL injection volume. Calibrations from LOD-150 μg/L were linear [r [Fe(II)]2 = 0.9999, r [Fe(III)]2 = 0.9951]. At higher concentrations Fe(II) curve flattened significantly. Measurement precision was 3.5% [Fe(II) at 62 μg/L] or 2.2% [Fe(III) at 112 μg/L] and migration time precision was 2% for Fe(III) and 3% for Fe(II), each determined in 1:2 diluted lysates of human neuroblastoma cells. Concentration determination accuracy was checked by parallel measurements of SH-SY5Y cell lysates with validated LC-ICP-MS method and by recovery experiments after standard addition. Accuracy (n = 6) was 97.6 ± 3.7% Fe(III) and 105 ± 6.6%Fe(II). Recovery [(a) +33 μg/L or (b) +500 μg/L, addition per species] was (a): 97.2 ± 13% [Fe(II)], 108 ± 15% [Fe(III)], 102.5 ± 7% (sum of species), and (b) 99±4% [Fe(II)], 101 ± 6% [Fe(III)], 100 ± 5% (sum of species). Migration time shifts in CSF samples were due to high salinity, but both Fe-species were identified by standard addition. AU - Michalke, B. AU - Willkommen, D. AU - Venkataramani, V.* C1 - 55752 C2 - 46503 CY - Avenue Du Tribunal Federal 34, Lausanne, Ch-1015, Switzerland TI - Iron redox speciation analysis using capillary electrophoresis coupled to inductively coupled plasma mass spectrometry (CE-ICP-MS). JO - Front. Chem. VL - 7 PB - Frontiers Media Sa PY - 2019 SN - 2296-2646 ER - TY - JOUR AB - This paper is a comprehensive study regarding the role of glutathione as a natural antioxidant on white wines aging potential. It includes sensory and ultrahigh resolution mass spectrometry (FTICR-MS) metabolomics of aged chardonnay wines from 2008 to 2009 vintages, made after glutathione spiking at alcoholic fermentation or bottling. The closure effect was also considered. The sensory analysis revealed a clear vintage, closure and glutathione effect on wines oxidative character after several years of bottle aging. Spearman rank correlation was applied to link the sensory analysis and the exact mass information from FT-ICR-MS. FTICR-MS along with multivariate statistical analyses put in evidence that glutathione efficiency against wines sensory oxidative stability is related to wines antioxidant metabolome consisting of N- and S- containing compounds like amino acids, aromatic compounds and peptides. The chemical composition and origin of wines antioxidant metabolome suggests that its management since the very beginning of the vinification process is a key factor to estimate wines aging potential. AU - Nikolantonaki, M.* AU - Julien, P.* AU - Coelho, C.* AU - Roullier-Gall, C. AU - Ballester, J.* AU - Schmitt-Kopplin, P. AU - Gougeon, R.D.* C1 - 53679 C2 - 44852 TI - Impact of glutathione on wines oxidative stability: A combined sensory and metabolomic study. JO - Front. Chem. VL - 6 IS - JUN PY - 2018 SN - 2296-2646 ER - TY - JOUR AB - Whisky can be described as a complex matrix integrating the chemical history from the fermented cereals, the wooden barrels, the specific distillery processes, aging, and environmental factors. In this study, using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), we analyzed 150 whisky samples from 49 different distilleries, 7 countries, and ranging from 1 day new make spirit to 43 years of maturation with different types of barrel. Chemometrics revealed the unexpected impact of the wood history on the distillate's composition during barrel aging, regardless of the whisky origin. Flavonols, oligolignols, and fatty acids are examples of important chemical signatures for Bourbon casks, whereas a high number of polyphenol glycosides, including for instance quercetin-glucuronide or myricetin-glucoside as potential candidates, and carbohydrates would discriminate Sherry casks. However, the comparison of barrel aged rums and whiskies revealed specific signatures, highlighting the importance of the initial composition of the distillate and the distillery processes. AU - Roullier-Gall, C. AU - Signoret, J.* AU - Hemmler, D. AU - Witting, M. AU - Kanawati, B. AU - Schaefer, B.W.* AU - Gougeon, R.D.* AU - Schmitt-Kopplin, P. C1 - 53199 C2 - 44471 CY - Lausanne TI - Usage of FT-ICR-MS metabolomics for characterizing the chemical signatures of barrel-aged whisky. JO - Front. Chem. VL - 6 PB - Frontiers Media Sa PY - 2018 SN - 2296-2646 ER - TY - JOUR AB - An overview of the critical steps for the non-targeted Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-ToF-MS) analysis of wine chemistry is given, ranging from the study design, data preprocessing and statistical analyses, to markers identification. UPLC-Q-ToF-MS data was enhanced by the alignment of exact mass data from FTICR-MS, and marker peaks were identified using UPLC-Q-ToF-MS(2). In combination with multivariate statistical tools and the annotation of peaks with metabolites from relevant databases, this analytical process provides a fine description of the chemical complexity of wines, as exemplified in the case of red (Pinot noir) and white (Chardonnay) wines from various geographic origins in Burgundy. AU - Roullier-Gall, C. AU - Witting, M. AU - Gougeon, R.D.* AU - Schmitt-Kopplin, P. C1 - 42853 C2 - 35815 TI - High precision mass measurements for wine metabolomics. JO - Front. Chem. VL - 2 PY - 2014 SN - 2296-2646 ER -