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Plasticizers and other plastics additives have been extensively used as ingredients of plastics and are as a result thereof easily released in the aquatic environment, due to different physical diffusion processes. In this context, a dedicated method was developed for the simultaneous quantification of 27 known and a virtually unlimited number of unknown alkylphenols, Bisphenol A and phthalates in 2 aquatic matrices, i.e. sea- and freshwater. To this extent, a novel instrumental HESI-UHPLC-HRMS (heated electro-spray ionization ultra-high performance liquid chromatographic high resolution mass spectrometric) method was devised for the simultaneous analysis of 7 phenols (i.e. 6 alkylphenols and Bisphenol A) and 20 phthalates within 10 min. Thereafter, a solid-phase extraction protocol was statistically (95% confidence interval, p > 0.05) optimized based on experimental designs. The method was proven fit-for-purpose through a successful validation at environmentally relevant nanomolar concentrations. Analytical precautions were taken for minimizing false-positive results to suppress in-house contamination. The method demonstrated an excellent analytical performance across all known plasticizers and plastics additives for sea- and freshwater, revealing good linearity (R2 > 0.99, n = 39), stable recoveries (98.5–105.8%), satisfactory repeatability (RSD

In recent years, metabolomics has surfaced as an innovative research strategy in human metabolism, whereby selection of the biological matrix and its inherent metabolome is of crucial importance. However, focusing on a single matrix may imply that relevant molecules of complementary physiological pathways, covered by other matrices, are missed. To address this problem, this study presents a unique multi-matrix platform for polar metabolic fingerprinting of feces, plasma and urine, applying ultra-high performance liquid-chromatography coupled to hybrid quadrupole-Orbitrap high-resolution mass spectrometry, that is able to achieve a significantly higher coverage of the system's metabolome and reveal more significant results and interesting correlations in comparison with single-matrix analyses. All three fingerprinting approaches were proven ‘fit-for-purpose’ through extensive validation in which a number of endogenous metabolites were measured in representative quality control samples. For targeted and untargeted validation of all three matrices, excellent linearity (coefficients of determination R2 ≥ 0.99 or 0.90 respectively), recovery and precision (coefficients of variance ≤ 15% or 30% respectively) were observed. The potential of the platform was demonstrated by subjecting fecal, urine and plasma samples (collected within one day) from ten healthy volunteers to metabolic fingerprinting, yielding respectively 9 672, 9 647, and 6122 components. Orthogonal partial least-squares discriminant analysis provided similar results for feces and plasma to discriminate according to gender (p-value, R2(X), R2(Y) and Q2(Y)), suggesting feces as an excellent alternative biofluid to plasma. Moreover, combining the different matrices improved the model's predictivity, indicating the superiority of multi-matrix platforms for research purposes in biomarker detection or pathway elucidation and in the selection of the most optimal matrix for future clinical purposes.

Industrial processing of fruit and vegetables can have detrimental effects on health-promoting phytochemicals. Here, a novel pilot-scale process using an innovative spiral-filter press followed by a thermal treatment was evaluated for the production of tomato juice. Three-month storage of the resulting juice was also evaluated. The process impact of the different unit processes, with emphasis on the novel spiral-filter pressing, was investigated for the three major compound classes present in tomato (ascorbic acid, phenolic compounds and carotenoids). The spiral-filter press processing did not seem to cause degradation of ascorbic acid, phenolic compounds or carotenoids, which can be ascribed to the fast processing in a low-oxygen atmosphere. Maintaining the native constitution of tomato to a great extent, the spiral-filter press thus offers potential for processing tomatoes and other vegetables into juices, smoothies and purees.

Lipophilic marine biotoxins, which are mainly produced by small dinoflagellates, are increasingly detected in coastal waters across the globe. As these producers are consumed by zooplankton and shellfish, the toxins are introduced, bioaccumulated and possibly biomagnified throughout marine food chains. Recent research has demonstrated that ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC–HRMS) is an excellent tool to detect marine toxins in algae and seafood. In this study, UHPLC–HRMS was used to screen lipophilic marine biotoxins in organisms from different trophic levels of the Belgian coastal zone ecosystem. A total of 20 tentatively identified lipophilic compounds was detected. Hereby, the trophic transfer of lipophilic marine biotoxins to the upper trophic level was considered to be rather limited. Furthermore, 36% of the compounds was clearly transferred between different organisms. A significant biotransformation of compounds from the okadaic acid and spirolide toxin groups was observed (64%), mainly in filter feeders. Through a multi-targeted approach, this study showed that marine organisms in the Belgian coastal zone are exposed to a multi-toxin mixture. Further research on both single compound and interactive toxic effects of the frequently detected lipophilic marine toxin ester metabolites throughout the food chain is therefore needed. As a future perspective, confirmatory identification of potential toxins by studying their fragmentation spectra (using new tools such as hybrid quadrupole Q-Exactive™ Orbitrap-MS) is designated.

The anaerobic digestion microbiome has been puzzling us since the dawn of molecular methods for mixed microbial community analysis. Monitoring of the anaerobic digestion microbiome can either take place via a non-targeted holistic evaluation of the microbial community through fingerprinting or by targeted monitoring of selected taxa. Here, we compared four different microbial community fingerprinting methods, i.e., amplicon sequencing, metaproteomics, metabolomics and cytomics, in their ability to characterise the full-scale anaerobic digestion microbiome. Cytometric fingerprinting through cytomics reflects a, for anaerobic digestion, novel, single cell-based approach of direct microbial community fingerprinting by flow cytometry. Three different digester types, i.e., sludge digesters, digesters treating agro-industrial waste and dry anaerobic digesters, each reflected different operational parameters. The α-diversity analysis yielded inconsistent results, especially for richness, across the different methods. In contrast, β-diversity analysis resulted in comparable profiles, even when translated into phyla or functions, with clear separation of the three digester types. In-depth analysis of each method's features i.e., operational taxonomic units, metaproteins, metabolites, and cytometric traits, yielded certain similar features, yet, also some clear differences between the different methods, which was related to the complexity of the anaerobic digestion process. In conclusion, cytometric fingerprinting through flow cytometry is a reliable, fast method for holistic monitoring of the anaerobic digestion microbiome, and the complementary identification of key features through other methods could give rise to a direct interpretation of anaerobic digestion process performance.

Ambient ionization-based techniques hold great potential for rapid point-of-care applicable metabolic fingerprinting of tissue and fluids. Hereby, feces represents a unique biospecimen as it integrates the complex interactions between the diet, gut microbiome and host, and is therefore ideally suited to study the involvement of the diet-gut microbiome axis in metabolic diseases and their treatments at a molecular level. We present a new method for rapid (

Recent studies support the hypothesis that the glucocorticoid prednisolone can be formed from cortisol under influence of stress. To evaluate this hypothesis, urine samples of supposedly non-stressed bovines (at the farm) and bovines subjected to two different forms of stress, i.e. upon slaughter (natural stress) or following administration of a synthetic analog of the adrenocorticotropic hormone (pharmacologically-induced stress) were analysed, and their urinary cortisol and prednisolone levels evaluated. At the farm, none of the examined samples exhibited urinary prednisolone levels higher than the CCα (0.09 μg L(-1)). Upon slaughter or following synthetically induced stress, significantly positive correlations between cortisol and prednisolone could be demonstrated, 0.52 and 0.69, respectively. Of all prednisolone-positive urine samples (n=84), only one showed a prednisolone levels (i.e. 6.45 μg L(-1)) above the threshold level of 5 μg L(-1) suggested by the European Reference Laboratories. Subsequently, an untargeted analysis was performed (metabolic fingerprinting) to characterize the urinary metabolite patterns related to the three different cattle groups. In this context, multivariate statistics assigned a total of 169 differentiating metabolites as playing a key role in the urinary pattern in response to stress. Three of these ions were defined as steroids using an in-house created database. As a result, the metabolic fingerprinting approach proved to be a powerful tool to classify unknown bovine urine samples that tested positive for prednisolone, while providing information about the stress status of the animal.

In recent years, the analysis of veterinary drugs and growth-promoting agents has shifted from target-oriented procedures, mainly based on liquid chromatography coupled to triple-quadrupole mass spectrometry (LC-QqQ-MS), towards accurate mass full scan MS (such as Time-of-Flight (ToF) and Fourier Transform (FT)-MS). In this study, the performance of a hybrid analysis instrument (i.e. UHPLC-QuadrupoleTime-of-Flight-MS (QqToF-MS)), able to exploit both full scan HR and MS/MS capabilities within a single analytical platform, was evaluated for confirmatory analysis of anabolic steroids (gestagens, estrogens including stilbenes and androgens) in meat. The validation data was compared to previously obtained results (CD 2002/657/EC) for QqQ-MS and single stage Orbitrap-MS. Additionally, a fractional factorial design was used to shorten and optimize the sample extraction. Validation according to CD 2002/657/EC demonstrated that steroid analysis using QqToF has a higher competing value towards QqQ-MS in terms of selectivity/specificity, compared to single stage Orbitrap-MS. While providing excellent linearity, based on lack-of-fit calculations ( F -test, α = 0.05 for all steroids except 17β-ethinylestradiol: α = 0.01), the sensitivity of QqToF-MS proved for 61.8% and 85.3% of the compounds more sensitive compared to QqQ-MS and Orbitrap-MS, respectively. Indeed, the CC α values, obtained upon ToF-MS/MS detection, ranged from 0.02 to 1.74 μg kg −1 for the 34 anabolic steroids, while for QqQ-MS and Orbitrap-MS values ranged from 0.04 to 0.88 μg kg −1 and from 0.07 to 2.50 μg kg −1 , respectively. Using QqToF-MS and QqQ-MS, adequate precision was obtained as relative standard deviations for repeatability and within-laboratory reproducibility, were below 20%. In case of Orbitrap-MS, some compounds (i.e. some estrogens) displayed poor precision, which was possibly caused by some lack of sensitivity at lower concentrations and the absence of MRM-like experiments. Overall, it can be concluded that QqToF-MS offers good quantitative and confirmatory performance using the ToF-MS/MS mode whereas the full scan HR-ToF-MS allows screening for potential new designer drugs.