Publications by authors named "Eva De Rijke"

15 Publications

  • Page 1 of 1

Effect-directed analysis and chemical identification of agonists of peroxisome proliferator-activated receptors in white button mushroom.

Food Funct 2021 Jan 7;12(1):133-143. Epub 2020 Dec 7.

BioDetection Systems, Science Park 406, 1098 XH Amsterdam, The Netherlands.

Obesity has a serious effect on human health. It relates to metabolic syndrome, including the associated disorders such as type 2 diabetes, heart disease, stroke and hyperemia. The peroxisome proliferator-activated receptors (PPARs) are important receptors to control fat metabolism in the human body. Because of the safety concerns of synthetic drugs targeting PPARs, ligands from natural sources have drawn interest. Earlier, we have found high PPAR activities in extracts from Agaricus bisporus (white button mushroom, WBM). WBM contains a wide range of candidate compounds which could be agonists of PPARs. To identify which compounds are responsible for PPAR activation by WBM extracts, we used fractionation coupled to effect-directed analysis with reporter gene assays specific for all three PPARs for purification and LC/MS-TOF and NMR for compound identification in purified active fractions. Surprisingly, we identified the relatively common dietary fatty acid, linoleic acid, as the main ligand of PPARs in WBM. Possibly, the relatively low levels of linoleic acid in WBM are sufficient and instrumental in inducing its anti-obesogenic effects, avoiding high energy intake and negative health effects associated with high levels of linoleic acid consumption. However, it could not be excluded that a minor relatively potent compound contributes towards PPAR activation, while the anti-obesity effects of WBM may be further enhanced by receptor expression modulating compounds or compounds with completely PPAR unrelated modes of action.
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http://dx.doi.org/10.1039/d0fo02071kDOI Listing
January 2021

Antagonistic activity towards the androgen receptor independent from natural sex hormones in human milk samples from the Norwegian HUMIS cohort.

Environ Int 2020 10 14;143:105948. Epub 2020 Jul 14.

BioDetection Systems bv, Science Park 406, 1098XH Amsterdam, the Netherlands.

In this paper, we investigated the possible presence of endocrine disrupting chemicals (EDCs) based on measuring the total estrogenic and androgenic activity in human milk samples. We used specific bioassays for analysis of the endocrine activity of estrogens and estrogen-like EDCs and androgens and androgen-like EDCs and developed a separation method to evaluate the contribution from natural hormones in comparison to that of EDCs to total endocrine activities. We extracted ten random samples originating from the Norwegian HUMIS biobank of human milk and analyzed their agonistic or antagonistic activity using the ERα- and AR CALUX® bioassays. The study showed antagonistic activity towards the androgen receptor in 8 out of 10 of the assessed human milk samples, while 2 out of 10 samples showed agonistic activity for the ERα. Further investigations demonstrated anti-androgenic activity in the polar fraction of 9 out of 10 samples while no apolar extracts scored positive. The culprit chemicals causing the measured antagonistic activity in AR CALUX was investigated through liquid chromatography fractionation coupled to bioanalysis and non-target screening involving UHPLC-Q-TOF-MS/MS, using a pooled polar extract. The analysis revealed that the measured anti-androgenic biological activity could not be explained by the presence of endogenous hormones nor their metabolites. We have demonstrated that human milk of Norwegian mothers contained anti-androgenic activity which is most likely associated with the presence of anthropogenic polar EDCs without direct interferences from natural sex hormones. These findings warrant a larger scale investigation into endocrine biological activity in human milk, as well as exploring the chemical sources of the activity and their potential effects on health of the developing infant.
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http://dx.doi.org/10.1016/j.envint.2020.105948DOI Listing
October 2020

Chemical attribution of the homemade explosive ETN - Part II: Isotope ratio mass spectrometry analysis of ETN and its precursors.

Forensic Sci Int 2020 Aug 29;313:110344. Epub 2020 May 29.

Van 't Hoff Institute for Molecular Sciences, Faculty of Science, University of Amsterdam, the Netherlands; CLHC, Amsterdam Center for Forensic Science and Medicine, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, the Netherlands.

In this follow-up study the collaboration between two research groups from the USA and the Netherlands was continued to expand the framework of chemical attribution for the homemade explosive erythritol tetranitrate (ETN). Isotope ratio mass spectrometry (IRMS) analysis was performed to predict possible links between ETN samples and its precursors. Carbon, nitrogen, hydrogen and oxygen isotope ratios were determined for a wide variety of precursor sources and for ETN samples that were prepared with selected precursors. The stability of isotope ratios of ETN has been demonstrated for melt-cast samples and two-year old samples, which enables sample comparison of ETN in forensic casework independent of age and appearance. Erythritol and nitric acid (or nitrate salt) are the exclusive donor of carbon and nitrogen atoms in ETN, respectively, and robust linear relationships between precursor and the end-product were observed for these isotopes. This allowed for defining isotopic enrichment ranges for carbon and nitrogen that support the hypothesis that a given erythritol or nitrate precursor was used to synthesize a specific ETN batch. The hydrogen and oxygen atoms in ETN do not originate from one exclusive donor material, making linkage prediction more difficult. However, the large negative enrichments observed for both isotopes do provide powerful information to exclude suspected precursor materials as donor of ETN. Additionally, combing the isotopic data of all elements results in a higher discrimination power for ETN samples and its precursor materials. Combining the findings of our previously reported LC-MS analysis of ETN with this IRMS study is expected to increase the robustness of the forensic comparison even further. The partially nitrated impurities can provide insight on the synthesis conditions while the isotope data contain information on the raw materials used for the production of ETN.
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http://dx.doi.org/10.1016/j.forsciint.2020.110344DOI Listing
August 2020

Investigation of the presence of prednisolone in bovine urine.

Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2014 Apr 3;31(4):605-13. Epub 2014 Mar 3.

a RIKILT part of Wageningen UR , European Union Reference Laboratory , Wageningen , the Netherlands.

Over the past two years low levels of prednisolone have been reported in bovine urine by a number of laboratories in European Union member states. Concentrations vary, but are reported to be below approximately 3 µg l(-1). Forty per cent of bovine urine samples from the Dutch national control plan had concentrations of prednisolone between 0.11 and 2.04 µg l(-1). In this study the mechanism of formation of prednisolone was investigated. In vitro conversion of cortisol by bacteria from faeces and soil, bovine liver enzymes and stability at elevated temperatures were studied. In vitro bovine liver S9 incubation experiments showed a significant 20% decrease of cortisol within 6 h, and formation of prednisolone was observed from 0.2 g l(-1) at t = 0 to 0.5 g l(-1) at t = 6. Under the influence of faeces, the stability of cortisol in urine is reduced and cortisol breaks down within 50 h. Prednisolone is formed up to 4 µg l(-1) at 70°C after 15 h. However, this decreases again to zero after 50 h. With soil bacteria, a slower decrease of cortisol was observed, but slightly higher overall formation of prednisolone, up to 7 µg l(-1) at 20°C. As opposed to incurred urine, in fortified urine incubated with faeces or soil bacteria no prednisolone was detected. This difference may be explained by the presence of natural corticosteroids in the incurred sample. With UPLC-QToF-MS experiments, in urine and water samples incubated with faeces, metabolites known from the literature could be (tentatively) identified as 20β-hydroxy-prednisolone, cortisol-21-sulfate, oxydianiline, tetrahydrocortisone-3-glucuronide and cortexolone, but for all compounds except 20β-hydroxy-prednisolone no standards were available for confirmation. Based on the results of this study and literature data, for regulatory purposes a threshold of 5 µg l(-1) for prednisolone in bovine urine is proposed. Findings of prednisolone in concentrations up to 5 µg l(-1) in bovine urine can, most likely, originate from other sources than illegal treatment with growth promoters.
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http://dx.doi.org/10.1080/19440049.2013.878479DOI Listing
April 2014

Selective androgen receptor modulators: in vitro and in vivo metabolism and analysis.

Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2013 24;30(9):1517-26. Epub 2013 Jul 24.

a European Union Reference Laboratory , RIKILT - Institute of Food Safety , Wageningen , the Netherlands.

For future targeted screening in National Residue Control Programmes, the metabolism of seven SARMs, from the arylpropionamide and the quinolinone classes, was studied in vitro using S9 bovine liver enzymes. Metabolites were detected and identified with ultra-performance liquid chromatography (UPLC) coupled to time-of-flight mass spectrometry (ToF-MS) and triple quadrupole mass spectrometry (QqQ-MS). Several metabolites were identified and results were compared with literature data on metabolism using a human cell line. Monohydroxylation, nitro-reduction, dephenylation and demethylation were the main S9 in vitro metabolic routes established. Next, an in vivo study was performed by oral administration of the arylpropionamide ostarine to a male calf and urine samples were analysed with UPLC-QToF-MS. Apart from two metabolites resulting from hydroxylation and dephenylation that were also observed in the in vitro study, the bovine in vivo metabolites of ostarine resulted in glucuronidation, sulfation and carboxylation, combined with either a hydroxylation or a dephenylation step. As the intact mother compounds of all SARMs tested are the main compounds present after in vitro incubations, and ostarine is still clearly present in the urine after the in vivo metabolism study in veal calves, the intact mother molecules were selected as the indicator to reveal treatment. The analytical UPLC-QqQ-MS/MS procedure was validated for three commercially available arylpropionamides according to European Union criteria (Commission Decision 2002/657/EC), and resulted in decision limits ranging from 0.025 to 0.05 µg l⁻¹ and a detection capability of 0.025 µg l⁻¹ in all cases. Adequate precision and intra-laboratory reproducibility (relative standard deviation below 20%) were obtained for all SARMs and the linearity was 0.999 for all compounds. This newly developed method is sensitive and robust, and therefore useful for confirmation and quantification of SARMs in bovine urine samples for residue control programmes and research purposes.
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http://dx.doi.org/10.1080/19440049.2013.810346DOI Listing
April 2014

Confirmation and 3D profiling of anabolic steroid esters in injection sites using imaging desorption electrospray ionisation (DESI) mass spectrometry.

Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2013 14;30(6):1012-9. Epub 2013 Jun 14.

RIKILT - Institute of Food Safety, Akkermaalsbos 2, 6708 WB Wageningen, The Netherlands.

In this study, desorption electrospray ionisation (DESI) linear ion trap tandem mass spectrometry (MS(n)) was applied for the confirmation and three-dimensional profiling of anabolic steroid esters in an injection site of bovine muscle. The spatial resolution of the DESI-MS(n) was demonstrated by scanning hormone esters and marker ink lines drawn at various distances on a microscopic slide at set distances, using an x-scanner with manual y and z adjustment. Tissue slices of bovine muscle injected with a hormone cocktail were analysed. All anabolic steroid esters could be directly detected in the sample and confirmed on the basis of identification points awarded for selected MS/MS transitions according to the performance criteria given in Commission Decision 2002/657/EC. Moreover, the injection site could be mapped by two-dimensional and three-dimensional imaging MS, showing a horizontal and vertical distribution through the muscle tissue. This DESI approach offers potential for analysis of injection sites of steroid esters from illegally treated animals; moreover, direct analysis by ambient imaging DESI-MS still allows conventional extraction and analysis of the whole tissue for further confirmatory or contra-analysis afterwards.
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http://dx.doi.org/10.1080/19440049.2013.794307DOI Listing
January 2014

New developments in umami (enhancing) molecules.

Chem Biodivers 2008 Jun;5(6):1195-203

Givaudan, Huizerstraatweg 28, NL-1411 GP Naarden.

As health has become one of the main drivers in nutrition, the scientific interest in taste receptors and taste molecules has increased considerably. Academia as well as flavor and food companies are searching for molecules that make food more healthy but not less appetizing. In the savory area, salt and umami taste are being investigated. This review deals with the progress made in umami tasting molecules. Umami taste has been known as a separate taste for a long time in Asian countries and has been generally accepted as the fifth basic taste in the last decade of the previous century. In this review, first the current level of understanding of the umami receptors will be described. The main part of the paper will deal with the umami-tasting molecules that have been published recently, including the work that has been performed within Givaudan itself. Lactoyl amides of GMP (guanosine monophosphate) appeared to have remarkably strong umami-tasting properties.
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http://dx.doi.org/10.1002/cbdv.200890096DOI Listing
June 2008

LC-MS study to reduce ion suppression and to identify N-lactoylguanosine 5'-monophosphate in bonito: a new umami molecule?

J Agric Food Chem 2007 Aug 11;55(16):6417-23. Epub 2007 Jul 11.

Department of Analytical Research, Givaudan, Huizerstraatweg 28, 1411 GP Naarden, The Netherlands.

In this study a specific taste modulating flavor ingredient, N-lactoylguanosine 5'-monophosphate (N-lactoyl GMP), was determined in bonito (Japanese, Katsuobushi, dried fermented skipjack) and in powdered bonito using liquid chromatography-electrospray ionization (+) mass spectrometry-mass spectrometry (LC-ESI(+)-MS/MS) with a methanol/ammonium acetate or formate gradient. Furthermore, the influence of ion suppression due to sample matrix effect was investigated and was found to substantially influence the total MS response of N-lactoyl GMP; by adjusting the LC conditions the response could be approximately 5-fold-enhanced. The N-lactoyl GMP concentrations in different types of bonito products were between 0.2 and 2.4 microg/g.
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http://dx.doi.org/10.1021/jf0704007DOI Listing
August 2007

Identification of N-gluconyl [corrected] ethanolamine in wine by negative electrospray ionization with post-column chloride attachment and accurate mass determination on a triple-quadrupole mass spectrometer.

J Chromatogr A 2007 Jul 22;1156(1-2):296-303. Epub 2006 Dec 22.

Quest International, Department of Analytical Research and Development, Naarden, The Netherlands.

In this study a specific taste modulating flavour-ingredient, N-gluconyl [corrected] ethanolamine, was determined in two Beerenauslese wines using two different LC-MS techniques. For a first screening LC-MS(2) on an ion-trap mass spectrometer with negative electrospray ionization (ESI(-)) was applied. Sensitivity (and selectivity) was successfully increased approx. 10-fold by post-column addition of chloroform to form [M+Cl](-) species. In a second step LC-MS(2) on a triple-quadrupole mass spectrometer in accurate mass mode confirmed the presence of N-gluconyl [corrected] ethanolamine in wine. The application of the right MS(2) transitions for an unambiguous identification is discussed. N-Gluconyl [corrected] ethanolamine concentrations in the wines were found to be 1.1 and 4.0 microg/l.
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http://dx.doi.org/10.1016/j.chroma.2006.12.065DOI Listing
July 2007

Liquid chromatography with accurate mass measurement on a triple quadrupole mass-spectrometer for the identification and quantification of N-lactoyl ethanolamine in wine.

Mol Nutr Food Res 2006 Apr;50(4-5):351-5

Quest International, Department of Analytical Research and Development, GP Naarden, The Netherlands.

In this study a specific taste-modulating flavor ingredient, N-lactoyl ethanolamine, was determined in two Beerenauslese wines using preparative LC, as a first isolation and concentration step, followed by LC-MS/MS on a triple quadrupole in accurate mass (AM) mode. The accurate masses of the analyte and three characteristic fragments were determined with mass accuracies between 8 and 20 ppm. N-lactoyl ethanolamine concentrations in the wines were 0.4 and 2.5 mg/L.
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http://dx.doi.org/10.1002/mnfr.200500199DOI Listing
April 2006

Analytical separation and detection methods for flavonoids.

J Chromatogr A 2006 Apr 14;1112(1-2):31-63. Epub 2006 Feb 14.

Quest International, Department of Analytical Research and Development, Huizerstraatweg 28, 1411 GP Naarden, The Netherlands.

Flavonoids receive considerable attention in the literature, specifically because of their biological and physiological importance. This review focuses on separation and detection methods for flavonoids and their application to plants, food, drinks and biological fluids. The topics that will be discussed are sample treatment, column liquid chromatography (LC), but also methods such as gas chromatography (GC), capillary electrophoresis (CE) and thin-layer chromatography (TLC), various detection methods and structural characterization. Because of the increasing interest in structure elucidation of flavonoids, special attention will be devoted to the use of tandem-mass spectrometric (MS/MS) techniques for the characterization of several important sub-classes, and to the potential of combined diode-array UV (DAD UV), tandem-MS and nuclear magnetic resonance (NMR) detection for unambiguous identification. Emphasis will be on recent developments and trends.
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http://dx.doi.org/10.1016/j.chroma.2006.01.019DOI Listing
April 2006

Changed isoflavone levels in red clover (Trifolium pratense L.) leaves with disturbed root nodulation in response to waterlogging.

J Chem Ecol 2005 Jun;31(6):1285-98

Department of Analytical Chemistry and Applied Spectroscopy, Vrije Universiteit, de Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands.

The effect of disturbed root nodulation on the quantitative and qualitative composition of the main isoflavonoid glucoside malonates, glucosides, and aglycones in the leaves of Trifolium pratense L. grown under waterlogging conditions was investigated. Isoflavonoids are involved in the regulation of root nodule activity and the establishment of the mycorrhizal association. Isoflavonoid determination was performed using reversed-phase liquid chromatography coupled to mass spectrometric and UV absorbance detection. In response to waterlogging, the concentrations of biochanin A and biochanin A-7-O-glucoside malonate, biochanin A-7-O-glucoside, and genistein-7-O-glucoside in the leaves increased two- to threefold after a lag period of 3 wk because of disturbed root nodulation. The other isoflavones detected formononetin, formononetin-7-O-glucoside malonate, and formononetin-7-O-glucoside-did not show any significant changes related to waterlogging. After restoring normal soil water conditions, the concentrations of biochanin A and its glucoside and glucoside-malonate rapidly returned to the initial values, whereas the concentration of genistein-7-O-glucoside remained high.
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http://dx.doi.org/10.1007/s10886-005-5286-1DOI Listing
June 2005

Liquid chromatography coupled to nuclear magnetic resonance spectroscopy for the identification of isoflavone glucoside malonates in T. pratense L. leaves.

J Sep Sci 2004 Sep;27(13):1061-70

Vrije Universiteit, Department of Analytical Chemistry and Applied Spectroscopy, de Boelelaan 1083, 1081 HV Amsterdam, the Netherlands.

Previous studies revealed that the main isoflavones in extracts of leaves of T. pratense L. are biochanin A and formononetin, their 7-O-glucosides, and two glucoside malonate isomers of each of them. Since LC-MS(/MS) did not provide sufficient information to distinguish the glucoside malonate isomers, in the present paper LC-NMR as well as off-line two-dimensional NMR were used to obtain further structural information. Matrix solid-phase dispersion (MSPD) was applied to obtain sufficiently high analyte concentrations to perform LC-NMR. Stop-flow reversed-phase LC-NMR was performed using a gradient of deuterated water and deuterated acetonitrile. Offline COSY and NOESY experiments were carried out to determine the positions of the glucose moiety on the flavonoid aglycone, and of the malonate moiety on the glucose. Based on the fragmentation patterns in MS/MS and the NMR spectra, the two formononetin glucoside malonate isomers were identified as 7-O-beta-D-glucoside 6"-O-malonate and 7-O-beta-D-glucoside 4"-O-malonate; i.e. they only differ in the substitution position of the malonate group on the glucoside ring. The biochanin A glucoside malonate isomers, however, have quite different structures. The main and later eluting isomer is biochanin A 7-O-beta-D-glucoside 6"-O-malonate, and the minor and earlier eluting isomer is 5-hydroxy-7-methoxyisoflavone 4'-O-beta-D-glucoside 4"-O-malonate: the positions of the methoxy group and the glucoside 6"-O-malonate group on the flavonoid skeleton are interchanged.
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http://dx.doi.org/10.1002/jssc.200401844DOI Listing
September 2004

Flavonoids in Leguminosae: analysis of extracts of T. pratense L., T. dubium L., T. repens L., and L. corniculatus L. leaves using liquid chromatography with UV, mass spectrometric and fluorescence detection.

Anal Bioanal Chem 2004 Feb 5;378(4):995-1006. Epub 2003 Dec 5.

Department of Analytical Chemistry and Applied Spectroscopy, Free University, de Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.

Reversed-phase LC on C-18 bonded silica with a methanol-ammonium formate gradient was used to determine the main flavonoids in leaves of four species of the Leguminosae family. The detection modes were diode-array UV absorbance, fluorescence, and (tandem) mass spectrometry. LC-UV was used for a general screening, sub-classification, and the calculation of total flavonoid contents. LC-FLU was included to identify isoflavones on the basis of their native fluorescence. Most structural information regarding aglycons, sugar moieties, and acidic groups was derived from LC-MS in both the full-scan and extracted-ion mode, using negative-ion atmospheric pressure chemical ionization. MS/MS did not provide much additional information, because the same fragments were observed as in full-scan MS. In T. pratense and T. repens, the main constituents were flavonoid glucoside-(di)malonates, while T. dubium and L. corniculatus mainly contained flavonoid (di)glycosides. Satellite sets comprising an aglycon, the glucoside and glucoside-malonates or -acetates, were abundantly present only in T. pratense. Generally speaking, the main aglycons and sugars in the four plant species are surprisingly different. In addition, while the results for T. pratense are similar to those reported in the literature, there is little agreement in the case of the other species. Finally, total flavonoid contents ranged from 50-65 mg/g for L. corniculatus and T. dubium, to 15 mg/g for T. pratense and only 1 mg/g for T. repens.
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http://dx.doi.org/10.1007/s00216-003-2310-6DOI Listing
February 2004

Liquid chromatography with atmospheric pressure chemical ionization and electrospray ionization mass spectrometry of flavonoids with triple-quadrupole and ion-trap instruments.

J Chromatogr A 2003 Jan;984(1):45-58

Department of Analytical Chemistry and Applied Spectroscopy, Free University, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.

With 15 flavonoids as test compounds, the analytical performance of four modes of LC-MS, multiple MS (MSn) and tandem MS operation (atmospheric pressure chemical ionization (APCI), electrospray ionization, positive and negative ionization) was compared for two mass spectrometers, a triple-quadrupole and an ion-trap instrument. Two organic modifiers, methanol and acetonitrile, and two buffers, ammonium acetate and ammonium formate, were used. In general, the use of APCI in the negative ion mode gave the best response, with the signal intensities and the mass-spectral characteristics not differing significantly between the two instruments. The best results were obtained when methanol-ammonium formate (pH 4.0) was used as LC eluent. Under optimum conditions full-scan limits of detection of 0.1-30 mg/l were achieved in the negative APCI mode. Here it needs to be emphasized that up to 2-order response differences were found both between analytes and between modes of ionization. This implies that one should be very cautious when interpreting data on the screening of real-life samples. The main fragmentations observed in the MSn spectra on the ion-trap, or the tandem MS spectra on the triple-quadrupole were generally the same. The advantage of the former approach is the added possibility to ascertain precursor-->product ion relationships.
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http://dx.doi.org/10.1016/s0021-9673(02)01868-xDOI Listing
January 2003
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