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1.
Clin Toxicol (Phila) ; 59(11): 975-981, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33755516

RESUMO

BACKGROUND: Weight loss and sports supplements containing deterenol have been associated with serious adverse events including cardiac arrest. OBJECTIVE: To determine the presence and quantity of experimental stimulants in dietary supplements labeled as containing deterenol sold in the United States. METHODS: Dietary supplements available for sale in the US and labeled as containing deterenol or one of its synonyms (e.g., isopropylnorsynephrine and isopropyloctopamine) were purchased online. For each brand, one container or subsample was analyzed by NSF International (Ann Arbor, MI) and one container or subsample by the Netherland's National Institute for Public Health and the Environment (RIVM, Bilthoven, The Netherlands). When differences existed between the two containers or subsamples of the same brand, both products were reanalyzed by Sciensano (Brussels, Belgium). NSF International carried out qualitative and quantitative analyses using ultra-high-performance liquid chromatography (UHPLC) quadrupole-Orbitrap mass spectrometry. RIVM performed qualitative and quantitative analysis using UHPLC quadrupole time-of-flight mass spectrometry. Sciensano carried out qualitative analysis using UHPLC quadrupole-Orbitrap mass spectrometry. RESULTS: Seventeen brands of supplements were analyzed. Many brands included more than one prohibited stimulant in the same product: 4 brands (24%, 4/17) included 2 stimulants, 2 (12%, 2/17) combined 3 stimulants, and 2 (12%, 2/17) combined 4 stimulants. The range of quantities per recommended serving size of the 9 stimulants detected were 2.7 mg to 17 mg of deterenol; 1.3 mg to 20 mg of phenpromethamine (Vonedrine); 5.7 mg to 92 mg of beta-methylphenylethylamine (BMPEA); 18 mg to 73 mg of octodrine; 18 mg to 55 mg of oxilofrine; 48 mg of higenamine; 17 mg of 1,3-dimethylamylamine (1,3-DMAA); 1.8 mg to 6.6 mg of 1,3-dimethylbutylamine (1,3-DMBA); and 5.3 mg of 1,4-dimethylamylamine (1,4-DMAA). CONCLUSION: Weight loss and sports supplements listing deterenol as an ingredient contained 9 prohibited stimulants and 8 different mixtures of stimulants, with as many as 4 experimental stimulants per product. These cocktails of stimulants have never been tested in humans and their safety is unknown.


Assuntos
Agonistas Adrenérgicos/análise , Fármacos Antiobesidade/análise , Estimulantes do Sistema Nervoso Central/análise , Suplementos Nutricionais/análise , Agonistas Adrenérgicos/efeitos adversos , Alcaloides/análise , Aminas/análise , Anfetaminas/análise , Fármacos Antiobesidade/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Qualidade de Produtos para o Consumidor , Suplementos Nutricionais/efeitos adversos , Efedrina/análogos & derivados , Efedrina/análise , Heptanos/análise , Humanos , Octopamina/análogos & derivados , Octopamina/análise , Medição de Risco , Tetra-Hidroisoquinolinas/análise , Estados Unidos
2.
Clin Toxicol (Phila) ; 56(6): 421-426, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29115866

RESUMO

BACKGROUND: The United States Food and Drug Administration banned the stimulant 1,3-dimethylamylamine (1,3-DMAA) from dietary supplements and warned consumers that the stimulant can pose cardiovascular risks ranging from high blood pressure to heart attacks. OBJECTIVES: We designed our study to determine if a new stimulant similar in structure to 1,3-DMAA has been introduced as an ingredient in supplements sold in the United States (US). METHODS: We analyzed six brands of supplements that listed an ingredient on the label (e.g., Aconitum kusnezoffii, DMHA or 2-amino-isoheptane) that might refer to an analog of 1,3-DMAA. Supplements were analyzed by two separate laboratories using ultra-high-performance liquid chromatography mass spectrometry and reference standards. RESULTS: Two previously unidentified 1,3-DMAA analogs (2-amino-6-methylheptane [octodrine] and 1,4-dimethylamylamine [1,4-DMAA]) and two banned stimulants (1,3-DMAA and 1,3-dimethylbutylamine [1,3-DMBA]) were identified. Octodrine was found at a dose (±95% CI) of 72 ± 7.5 mg per serving. In Europe, octodrine was previously sold as a pharmaceutical in multi-ingredient medications at dosages from 8 to 33 mg. The quantity of octodrine found in our study was more than twice the largest pharmaceutical dose. The other new stimulant, 1,4-DMAA, has not previously been approved for human consumption, and its safety in humans is unknown. 1,4-DMAA was found at dosages between 21 ± 11 mg to 94 ± 48 mg per serving. In addition, two banned stimulants - 1,3-DMAA and 1,3-DMBA - were also identified: 24 ± 7.6 mg to 35 ± 11 mg of 1,3-DMAA and 51 ± 16 mg of 1,3-DMBA. In one product, 24 ± 7.6 mg of 1,3-DMAA was combined with 21 ± 11 mg of 1,4-DMAA. 1,3-DMAA has been investigated as potentially contributing to hemorrhagic strokes and sudden death, whereas the safety of 1,3-DMBA in humans is unknown. CONCLUSION: Two banned stimulants (1,3-DMAA and 1,3-DMBA) and two previously unidentified stimulants (1,4-DMAA and octodrine) were identified in supplements sold in the United States.


Assuntos
Aminas/análise , Fármacos Antiobesidade/análise , Suplementos Nutricionais/análise , Aminas/efeitos adversos , Fármacos Antiobesidade/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Dopagem Esportivo , Heptanos/efeitos adversos , Heptanos/análise , Humanos
3.
Anal Bioanal Chem ; 394(5): 1463-70, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19396589

RESUMO

A sensitive method for the fast analysis of filbertone in spiked olive oil samples is presented. The applicability of a headspace (HS) autosampler in combination with a gas chromatograph (GC) equipped with a programmable temperature vaporizer (PTV) and a mass spectrometric (MS) detector is explored. A modular accelerated column heater (MACH) was used to control the temperature of the capillary gas chromatography column. This module can be heated and cooled very rapidly, shortening total analysis cycle times to a considerable extent. The proposed method does not require any previous analyte extraction, filtration and preconcentration step, as in most methods described to date. Sample preparation is reduced to placing the olive oil sample in the vial. This reduces the analysis time and the experimental errors associated with this step of the analytical process. By using headspace generation, the volatiles of the sample are analysed without interference by the non-volatile matrix, and by using injection in solvent-vent mode at the PTV inlet, most of the compounds that are more volatile than filbertone are purged and the matrix effect is minimised. Use of a liner packed with Tenax-TA allowed the compound of interest to be retained during the venting process. The limits of detection and quantification were as low as 0.27 and 0.83 microg/L, respectively, and precision (measured as the relative standard deviation) was 5.7%. The method was applied to the determination of filbertone in spiked olive oil samples and the results revealed the good accuracy obtained with the method.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Heptanos/análise , Óleos de Plantas/química , Software , Temperatura Alta , Azeite de Oliva , Sensibilidade e Especificidade , Volatilização
4.
J Agric Food Chem ; 56(2): 517-27, 2008 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-18163560

RESUMO

An extract of red bell peppers ( Capsicum annuum) was prepared by simultaneous distillation-extraction (SDE, Likens-Nickerson). In addition to the already known (3 E)-3-hepten-2-one ( 1), the unsaturated C9-ketones 1-nonen-4-one ( 2), (2 E)-2-nonen-4-one ( 3), and (2 E,5 E)-2,5-nonadien-4-one ( 4), 2-methoxy-3-isobutylpyrazine ( 5), and heptane-2-thiol ( 6), we identified 19 new thiols (the aliphatic saturated and unsaturated thiols 14- 16, and 22- 27, the mercapto-ketones 12 and 13, the mercapto-alcohols 17, 18, and 30, the dithiols 19 and 28, the methylthio-thiols 20 and 21, and the thiophene-thiol 31) and the two new dithiolanes 10 and 29. All of them are structurally related to the unsaturated C7- and C9-ketones 1- 4. The free thiols were enriched using Affi-Gel 501 ( p-aminophenyl-mercuric acetate grafted on an agarose gel). The new compounds were confirmed by syntheses and were organoleptically evaluated.


Assuntos
Capsicum/química , Extratos Vegetais/química , Compostos de Sulfidrila/análise , Compostos de Enxofre/análise , Alcanos/análise , Heptanos/análise , Cetonas/análise , Volatilização
5.
J Sep Sci ; 29(5): 691-4, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16605089

RESUMO

The enantioselectivity of heptakis(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl-beta-CD) toward racemic filbertone (E-5-methyl-hep-2-en-4-one) was studied by performing the chiral separation on a capillary column, a thick-film wide-bore column and a semipreparative column. The semipreparative enantioseparation of filbertone was achieved at 80 degrees C by using a packed column providing (R)- and (S)-enantiomers of filbertone with ee 90 and 96%, respectively. The isolated enantiomers (approximately 250 microg each, ee = 90-96%) may be used for studies on the relationship of chirality and biological activity by olfactory screening and toxicological studies.


Assuntos
Cromatografia Gasosa/métodos , Heptanos , Estereoisomerismo , Heptanos/análise , Heptanos/isolamento & purificação , Óleos de Plantas/química
6.
J Chromatogr A ; 1074(1-2): 215-21, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15941058

RESUMO

Control of adulteration of olive oil, together with authentication and contamination, is one of the main aspects in the quality control of olive oil. Adulteration with hazelnut oil is one of the most difficult to detect due to the similar composition of hazelnut and olive oils; both virgin olive oil and olive oil are subjected to that kind of adulteration. The main objective of this work was to develop an analytical method able to detect adulteration of virgin olive oils and olive oils with hazelnut oil by means of its analysis by a headspace autosampler directly coupled to a mass spectrometer used as detector (ChemSensor). As no chromatographic separation of the individual components of the samples exists, a global signal of the sample is obtained and employed for its characterization by means of chemometric techniques. Four different crude hazelnut oils from Turkey were employed for the development of the method. Multivariate regression techniques (partial least squares and principal components analysis) were applied to generate adequate regression models. Good values were obtained in both techniques for the parameters employed (standard errors of prediction (SEP) and prediction residual error sum of squares (PRESS)) to evaluate its goodness. With the proposed method, minimum adulteration levels of 7 and 15% can be detected in refined and virgin olive oils, respectively. Once validated, the method was applied to the detection of such adulteration in commercial olive oil and virgin olive oil samples.


Assuntos
Contaminação de Alimentos/análise , Espectrometria de Massas/métodos , Óleos de Plantas/análise , Óleos de Plantas/normas , Corylus , Heptanos/análise , Análise Multivariada , Azeite de Oliva , Reconhecimento Automatizado de Padrão/métodos
7.
J Agric Food Chem ; 52(2): 306-10, 2004 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-14733513

RESUMO

2-Heptanethiol was identified for the first time as a constituent of red and green bell pepper extracts. The chemical structure of this new aroma compound was proposed on the basis of mass spectra and retention indices and confirmed by chemical synthesis and nuclear magnetic resonance spectroscopy measurements. Its aroma properties were described as sulfury, onion-like, and vegetable-like, reminiscent of bell pepper at lower concentrations, with an orthonasal detection threshold of 10 microg/L of water. No differences in odor note and threshold value were observed for the enantiomeric forms, which were prepared from enantiopure 2-heptanol by tosylation, followed by thioacetylation and reduction, giving the target thiol enantiomers.


Assuntos
Capsicum/química , Heptanos/análise , Heptanos/síntese química , Odorantes/análise , Compostos de Sulfidrila/análise , Compostos de Sulfidrila/síntese química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/química , Estereoisomerismo , Volatilização
8.
J Agric Food Chem ; 51(9): 2496-500, 2003 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-12696926

RESUMO

The enantiomeric distribution of filbertone was determined in unroasted and roasted hazelnut oils of different geographical origins by using solid-phase microextraction (SPME) and capillary gas chromatography. An optimization procedure including SPME fiber, extraction time, exposure temperature, and sample volume enabled the best conditions to be selected. Under the optimized conditions, detection limits were in the micrograms per liter level for both enantiomers of filbertone with relative standard deviation values of 7.1 and 4.9% for R-filbertone and S-filbertone, respectively. The proposed approach allowed the rapid determination of the enantiomeric composition of filbertone and demonstrated that its variability is an inherent property of the natural compound. Analysis of two batches of hazelnut oils obtained from either unroasted or roasted hazelnuts showed, in general, significantly higher amounts of filbertone in roasted hazelnut oils.


Assuntos
Corylus/química , Heptanos/análise , Nozes/química , Óleos de Plantas/química , Cromatografia Gasosa/métodos , Manipulação de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Heptanos/química , Óleos de Plantas/análise , Estereoisomerismo , Temperatura , Fatores de Tempo
9.
Z Lebensm Unters Forsch ; 167(2): 82-6, 1978 Aug 30.
Artigo em Alemão | MEDLINE | ID: mdl-706808

RESUMO

The results of the determination of oil content depend on the method and on the solvent used. Extractions by the Twisselmann method give increasing yields in the order n-pentane, hexane, and n-heptane. Using the Soxhlet extraction, much lower yields were obtained with n-heptane than with the other two solvents. In both methods, the phospholipid content in the extracts depends only on the solvent and not on the method used. The yield and composition of the mixture of phospholipids vary in the different methods of extraction.


Assuntos
Óleos/análise , Fosfolipídeos/análise , Brassica/análise , Cromatografia em Camada Fina , Heptanos/análise , Hexanos/análise , Pentanos/análise , Extratos Vegetais/análise , Solubilidade , Solventes
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