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1.
Food Chem ; 297: 124896, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253254

RESUMO

We report here the results of the study of the chemical composition of Cyperus esculentus rhizomes. Ethanolic extracts have been separated by column chromatography and analyzed by magnetic resonance spectroscopy and mass spectrometry. Quercetin, stigmasterol, and linoleic and oleic acid glycerol esters, together with 4-chlorobutyl oleate, oleamide, myricetin, tyramine and N-feruloyltyramine, found for the first time in Cyperus esculentus rhizomes, have been isolated and quantified in the extracts. Alkaloids have not been detected, and the presence of flavonoids and sterols is moderate.


Assuntos
Cyperus/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Cyperus/metabolismo , Flavonoides/análise , Flavonoides/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/análise , Quercetina/análise , Quercetina/isolamento & purificação , Rizoma/química , Rizoma/metabolismo
2.
Biomed Res Int ; 2013: 790570, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24163820

RESUMO

Liquid and solid samples from two wastewater treatment plants (WWTPs) on Gran Canaria Island (Spain) have been tested for the presence of compounds with endocrine-disrupting properties. The selected degradation stages were sampled bimonthly from each WWTP over the 12-month period from July 2010 to July 2011. The analytical methods used for the determination of the endocrine-disrupting compounds (EDCs) were based on on-line solid phase extraction, microwave-assisted extraction (MAE), and ultrasonic-assisted extraction (UAE) coupled to UHPLC-MS/MS. All of the hyphenated methodologies employed in this work showed good recoveries (72-104%) and sensitivities, with LODs lower than 7.0 ng L(-1) and 6.3 ng g(-1) for the dissolved and solid fractions, respectively. We have also evaluated the estrogenicity of the samples in terms of their estradiol equivalent concentrations (EEQs). The chemical analysis of the selected EDCs revealed fairly low concentrations for both natural and synthetic oestrogens, alkylphenolic compounds, and bisphenol-A in each of the dissolved, particulate, and sludge samples (ng L(-1) or ng g(-1)). However, the estimated estrogenic activity indicated that the majority of samples could represent an important environmental risk, clearly surpassing the threshold to exert deleterious consequences on living beings.


Assuntos
Estrogênios/efeitos adversos , Estrogênios/análise , Instalações de Eliminação de Resíduos , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Humanos , Espanha
3.
J Chromatogr A ; 1230: 66-76, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22342207

RESUMO

A process using a fully automated on-line solid-phase extraction system combined with ultra-high-performance liquid chromatography and tandem mass spectrometry detection (SPE-UHPLC-MS/MS) has been developed and applied to the determination of 27 endocrine disrupting compounds (EDCs) in sewage samples. This technology allows separation and detection of all substances in a single chromatographic run that requires less than 4 min. In order to obtain a more sensitive method for the quantification of these compounds in sewage samples, an on-line solid-phase extraction step with Oasis HLB columns was performed prior to chromatographic determination. The complete analysis of each sample by this process requires only 9 min, provides satisfactory recoveries (72-110%) and limits of detection on the order of a few nanograms per liter (0.3-2.1 ng L(-1)), demonstrating their potential for analyses of environmental samples. Thus, this methodology has been applied to samples collected from two wastewater treatment plants (WWTPs) located in Las Palmas de Gran Canaria (Canary Islands, Spain). One of these plants utilised conventional activated sludge treatment (CAS), while the other employed biomembrane reactor treatment (MBR).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Disruptores Endócrinos/análise , Esgotos/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , Limite de Detecção , Espanha
4.
Talanta ; 85(4): 1825-34, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21872026

RESUMO

In this work, we present the development and application of a microwave assisted extraction followed by liquid chromatography-tandem mass spectrometry methodology (MAE-LC-MS/MS) for the determination of various estradiol-mimicking compounds in sewage sludge samples. For the purification of the MAE extracts, we have employed a solid phase extraction (SPE) clean-up procedure, previously optimised. The entire method provides recoveries between 71.7% and 103.1%, with relative standard deviation lower than 11.1% and limits of detection ranging from 0.6 to 3.5 ng g(-1). The developed method was applied to samples from three wastewater treatment plants (WWTPs) located in Las Palmas of Gran Canaria (Spain), two of which had a conventional activated sludge treatment (AST), whereas the third treatment plant had an advanced membrane bioreactor treatment (MBR). All of the analytes in the study, including (nonylphenol (NP), octylphenol (OP), and some of their ethoxylated chains AP(n)EOs (n ≤ 7), 17ß-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE) and bisphenol-A (BPA)), were found in almost all samples in concentrations ranging from 0.9 to 710.2 ng g(-1).


Assuntos
Cromatografia Líquida/métodos , Disruptores Endócrinos/análise , Disruptores Endócrinos/isolamento & purificação , Micro-Ondas , Esgotos/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Estradiol/metabolismo , Controle de Qualidade , Gerenciamento de Resíduos
5.
J Hazard Mater ; 183(1-3): 701-11, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20724070

RESUMO

Recently, many chemicals released into the environment have been shown to mimic endogenous hormones such as estradiol. It has been demonstrated that these compounds cause several adverse effects on wildlife and humans, such as the feminization of animal species, development of physical abnormalities and birth defects, and reproductive failure. In an effort to model the behaviour of some endocrine-disrupting chemicals (EDCs) and to establish the level of contamination in sewage samples, a quantitative method for the simultaneous determination of nonylphenol, octylphenol and corresponding ethoxylates (1-12), 17α-ethynylestradiol, bisphenol-A, and 17ß-estradiol and two of its metabolites have been developed. Identification and quantification were achieved by high performance liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS). Satisfactory detection limits (between 0.5-6 ng L(-1) in the dissolved phase and 1.4-12.7 ng g(-1) in the particulate phase) and analyte recoveries (between 60% and 108%) were achieved for target compounds. The optimised method was applied to the determination of EDCs in liquid sewage samples collected from a wastewater treatment plant (WWTP) in Las Palmas de Gran Canaria (Spain). Concentrations of EDCs ranged from <10 ng L(-1) to nearly 1200 ng L(-1) in the dissolved phase, and from 0.005 µg g(-1) to 2.8 µg g(-1) in the suspended particulate matter.


Assuntos
Disruptores Endócrinos/análise , Esgotos/análise , Poluentes Químicos da Água/análise , Compostos Benzidrílicos , Cromatografia Líquida , Estradiol/análise , Etinilestradiol/análise , Etil-Éteres/análise , Limite de Detecção , Fenóis/análise , Polímeros/análise , Extração em Fase Sólida , Espanha , Espectrometria de Massas em Tandem
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