2022-10-04, Erdin, Yves, Schlotterbeck, Götz, Mink, Christian

The market for plant protection products (PPPs) is one of the most regulated. With increasing regulations for registering PPPs, its requirements take more effort and more testing. Meanwhile, there is also an increasing market for illegal PPPs. While legally registered PPPs are thoroughly tested and documented, illegal PPPs are sold upfront without any testing (e.g., tox, aqua tox, eco tox). This bears additional risk for the users, the ecosystem and the public. There are many well established analytical methods and protocols to analyse soil, plant products as well as for food and beverage, but less for PPPs. Many methods need laborious sample preparation and extraction steps like QuEChERS and/or advanced mass spectrometry techniques. Here we present a method developed to identify active ingredients (AIs) which is easy to apply at relatively cheap costs and widely available instrumentation. It provides a straightforward set-up for sample preparation and analysis, without the need for elaborative sample preparation. The method validation showed sufficient linearity, repeatability and specificity to use this method for screening of samples taken from market control for counterfeit or cross contamination checks.

2022-03-29, Imbery, Carolin A., Dieterle, Frank, Ottka, Claudia, Weber, Corinna, Müller, Elisabeth, Lohi, Hannes, Giger, Urs, Schlotterbeck, Götz

Hepatopathies can cause major metabolic abnormalities in humans and animals. This study examined differences in serum metabolomic parameters and patterns in left-over serum samples from dogs with either congenital portosystemic shunts (cPSS, n = 24) or high serum liver enzyme activities (HLEA, n = 25) compared to control dogs (n = 64). A validated targeted proton nuclear magnetic resonance spectroscopy platform was used to assess 123 parameters. Principal component analysis of the serum metabolome demonstrated distinct clustering among individuals in each group, with the cluster of HLEA being broader compared to the other groups, presumably due to the wider spectrum of hepatic diseases represented in these samples. While younger and older adult control dogs had very similar metabolomic patterns and clusters, there were changes in many metabolites in the hepatopathy groups. Higher phenylalanine and tyrosine concentrations, lower branched-chained amino acids (BCAAs) concentrations, and altered fatty acid parameters were seen in cPSS dogs compared to controls. In contrast, dogs with HLEA had increased concentrations of BCAAs, phenylalanine, and various lipoproteins. Machine learning based solely on the metabolomics data showed excellent group classification, potentially identifying a novel tool to differentiate hepatopathies. The observed changes in metabolic parameters could provide invaluable insight into the pathophysiology, diagnosis, and prognosis of hepatopathies.

2022-08-30, Wölnerhanssen, Bettina K., Meyer-Gerspach, Anne Christin, Bordier, Valentine, Teysseire, Valentine, Senner, Frank, Schlotterbeck, Götz, Drewe, Jürgen, Beglinger, Christoph

The natural sweeteners erythritol and xylitol might be helpful to reduce sugar consumption and therefore prevent obesity and diabetes. The aim of the present study was to determine the absorption and metabolization into erythronate of different concentrations of erythritol and xylitol. Seventeen healthy lean participants received intragastric solutions of 10, 25, or 50 g erythritol or 7, 17, or 35 g xylitol on three study days in a randomized order. The study was double blinded with respect to the doses administered. We assessed plasma concentrations of erythritol, xylitol, and erythronate at fixed time intervals after administration with gas chromatography-mass spectrometry. We found: (i) a dose-dependent and saturable absorption of erythritol, (ii) a very low absorption of xylitol, (iii) a dose-dependent metabolization of erythritol into erythronate, and (iv) no metabolization of xylitol into erythronate. The implications of the metabolization of erythritol into erythronate for human health remain to be determined and more research in this area is needed.

2022-04-09, Imbery, Carolin Anna, Dieterle, Frank, Ottka, Claudia, Weber, Corinna, Müller, Elisabeth, Lohi, Hannes, Giger, Urs, Schlotterbeck, Götz

The adrenal glands play a major role in metabolic processes, and both excess and insufficient serum cortisol concentrations can lead to serious metabolic consequences. Hyper- and hypoadrenocorticism represent a diagnostic and therapeutic challenge. Serum samples from dogs with untreated hyperadrenocorticism (n = 27), hyperadrenocorticism undergoing treatment (n = 28), as well as with untreated (n = 35) and treated hypoadrenocorticism (n = 23) were analyzed and compared to apparently healthy dogs (n = 40). A validated targeted proton nuclear magnetic resonance (1H NMR) platform was used to quantify 123 parameters. Principal component analysis separated the untreated endocrinopathies. The serum samples of dogs with untreated endocrinopathies showed various metabolic abnormalities with often contrasting results particularly in serum concentrations of fatty acids, and high- and low-density lipoproteins and their constituents, which were predominantly increased in hyperadrenocorticism and decreased in hypoadrenocorticism, while amino acid concentrations changed in various directions. Many observed serum metabolic abnormalities tended to normalize with medical treatment, but normalization was incomplete when compared to levels in apparently healthy dogs. Application of machine learning models based on the metabolomics data showed good classification, with misclassifications primarily observed in treated groups. Characterization of metabolic changes enhances our understanding of these endocrinopathies. Further assessment of the recognized incomplete reversal of metabolic alterations during medical treatment may improve disease management.