Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
1.
Sci Total Environ ; 912: 169454, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38123101

RESUMEN

Using reclaimed water for agricultural irrigation is increasing worldwide to compensate for water scarcity. The aim of this work was to evaluate the uptake of some of the most commonly detected organic contaminants of emerging concern (CECs) and pesticides in regenerated water in a field study. Furthermore, it was studied their distribution and accumulation in the different parts of a crop (soil, plant and fruit). Three crops (cucumber, pepper and melon) were grown under controlled agronomic conditions in a greenhouse. In order to make an accurate evaluation of the process, "regenerated blank water" was spiked with 70 chemicals (including antibiotics, anti-inflammatories, analgesics, anaesthetics, anxiolytics, anticonvulsants, pesticides) at environmental concentrations (∼1 µg/L) and used for continuous crop irrigation. After crop season, the average total concentration of contaminants detected in the soil samples ranged from 132 to 232 µg/kg d.w depending of the crops type. Between 7 and 10 different contaminants were found in the harvested fruits, up to levels of 27.8 µg/kg f.w. cucumber, 12.4 µg/kg f.w. melon and 7.8 µg/kg f.w pepper. In general, cucumber fruit showed higher accumulation levels of contaminants than pepper and melon for most target analytes. The accumulation rates followed the order: root (0.2 %) < stem/leaf (1-4 %) < fruit (1-6 %) < soil (17-30 %). The experimental data obtained in this study were also used to assess the risk associated with the reuse of reclaimed water for crop irrigation as well to identify those contaminants that, due to their physicochemical properties, show higher accumulation rates and environmental impact.


Asunto(s)
Cucumis sativus , Plaguicidas , Agua , Productos Agrícolas , Agricultura , Riego Agrícola , Suelo
2.
Sci Total Environ ; 859(Pt 2): 160462, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36435246

RESUMEN

The use of reclaimed water for crop irrigation has been proposed as a suitable alternative for farmers in the coastal areas of Mediterranean countries, which suffer from greater water scarcity. In this work we study the impact on the water-soil-plant continuum of using reclaimed water for commercial crops irrigated over a long period, as well as the human risks associated with consuming the vegetables produced. Forty-four CECs were identified in the reclaimed water used for crop irrigation. Of these, twenty-four CECs were identified in the irrigated soil samples analysed. Tramadol, ofloxacin, tonalide, gemfibrozil, atenolol, caffeine, and cetirizine were the pharmaceuticals detected at the highest levels in the water samples (between 11 and 44 µg/L). The CECs with the highest average soil concentrations were tramadol (14.6 µg/kg), followed by cetirizine (13.2 µg/kg) and clarithromycin (12.7 µg/kg). In the irrigated vegetable samples analysed over the study period, carbamazepine, lidocaine, and caffeine were only detected at levels from 0.1 to 1.7 µg/kg. The CEC accumulation rate detected in the edible parts of the vegetables permanently irrigated with reclaimed water was very low (~1 %), whereas it was 33 % in the soils. The results revealed that consuming fruits harvested from plants irrigated for a long period with reclaimed water does not represent a risk to human health, opening the door to a circular economy of water. Nevertheless, for crop irrigation, future studies need to be conducted over longer periods and in other matrices to provide more scientific data on the safety of using reclaimed water.


Asunto(s)
Riego Agrícola , Contaminantes del Suelo , Humanos , Agua/análisis , Aguas Residuales , Productos Agrícolas , Suelo , Verduras , Contaminantes del Suelo/análisis
3.
Anal Methods ; 13(36): 4131-4142, 2021 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-34554152

RESUMEN

In this study, we aimed to validate and apply a quick and easy extraction method for the simultaneous determination of 27 pesticide residues at trace levels in agricultural samples (soil, fruit, and leaf) to monitor the presence of these contaminants released from reclaimed water. The procedure was based on a salting-out extraction method with acidified acetonitrile, followed by a dispersive solid-phase extraction (d-SPE) clean-up step applying the C18 sorbent. Ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry (LC-MS/MS) was used for identification and quantification of the target analytes. This methodology provided recovery values higher than 70%, for all pesticides and matrices evaluated in the study, except for propamocarb in soil samples (35%). Repeatability and reproducibility results, calculated as relative standard deviations (RSD, %), ranged between 1% and 18% in both cases. No remarkable matrix effects were observed for vegetable samples, except for thiamethoxam in red cabbage, and hexythiazox in carrot and leaves (between 30 and 40%). Soil samples showed a moderate matrix effect (between 21 and 35%) for more than 80% of the compounds. Monitoring pesticide residues found in agricultural samples irrigated with contaminated reclaimed water under controlled conditions revealed the efficacy of the proposed method. Three common vegetables were grown to evaluate the different migration and distribution rates in crops and soil. Pesticide accumulation in the different parts of the crop (soil, fruit, and leaves) and the potential human exposure to pesticides through daily intake were also discussed.


Asunto(s)
Residuos de Plaguicidas , Cromatografía Liquida , Humanos , Residuos de Plaguicidas/análisis , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Agua
4.
Sci Total Environ ; 782: 146759, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33838369

RESUMEN

In this study, we aimed to develop and validate a quick, easy, and robust extraction method for the simultaneous determination of 30 organic contaminants of emerging concern (CECs) including some transformation products in soil samples. Three different extraction methods based on an ultrasonic cylindrical probe (UAE), a pressurized liquid extraction (PLE), and a QuEChERS method were compared. Ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry (LC-MS/MS) was used for identification and quantification of the target analytes. A modified QuEChERS method showed the best results in terms of extractability and accuracy. The extraction procedure developed provided adequate extraction performances (70% of the target analytes were recovered within a 70-99% range), with good repeatability and reproducibility (variations below 20%) and great sensitivity (LOQ < 0.1 ng/g in most cases). No matrix effects were observed for 70% of the compounds. Finally, the analytical methodology was applied in a pilot study where agricultural soil was irrigated with reclaimed water spiked with the contaminants under study. Of the 25 CECs added in irrigation water, a total of 13 pesticides and 5 pharmaceutical products were detected at concentration ranges from 0.1 to 1.2 ng/g (d.w) and from 0.1 to 2.0 ng/g (d.w), respectively.

5.
Infect Immun ; 88(4)2020 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-31964743

RESUMEN

Invasive aspergillosis (IA) is a life-threatening infection that affects an increasing number of patients undergoing chemotherapy or allo-transplantation, and recent studies have shown that genetic factors contribute to disease susceptibility. In this two-stage, population-based, case-control study, we evaluated whether 7 potentially functional single nucleotide polymorphisms (SNPs) within the ARNT2 and CX3CR1 genes influence the risk of IA in high-risk hematological patients. We genotyped selected SNPs in a cohort of 500 hematological patients (103 of those had been diagnosed with proven or probable IA), and we evaluated their association with the risk of developing IA. The association of the most interesting markers of IA risk was then validated in a replication population, including 474 subjects (94 IA and 380 non-IA patients). Functional experiments were also performed to confirm the biological relevance of the most interesting markers. The meta-analysis of both populations showed that carriers of the ARNT2rs1374213G, CX3CR1rs7631529A, and CX3CR1rs9823718G alleles (where the RefSeq identifier appears as a subscript) had a significantly increased risk of developing IA according to a log-additive model (P value from the meta-analysis [PMeta] = 9.8 · 10-5, PMeta = 1.5 · 10-4, and PMeta =7.9 · 10-5, respectively). Haplotype analysis also confirmed the association of the CX3CR1 haplotype with AG CGG with an increased risk of IA (P = 4.0 · 10-4). Mechanistically, we observed that monocyte-derived macrophages (MDM) from subjects carrying the ARNTR2rs1374213G allele or the GG genotype showed a significantly impaired fungicidal activity but that MDM from carriers of the ARNT2rs1374213G and CX3CR1rs9823718G or CX3CR1rs7631529A alleles had deregulated immune responses to Aspergillus conidia. These results, together with those from expression quantitative trait locus (eQTL) data browsers showing a strong correlation of the CX3CR1rs9823718G allele with lower levels of CX3CR1 mRNA in whole peripheral blood (P = 2.46 · 10-7) and primary monocytes (P = 4.31 · 10-7), highlight the role of the ARNT2 and CX3CR1 loci in modulating and predicting IA risk and provide new insights into the host immune mechanisms involved in IA development.


Asunto(s)
Translocador Nuclear del Receptor de Aril Hidrocarburo/genética , Aspergillus/inmunología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Receptor 1 de Quimiocinas CX3C/genética , Predisposición Genética a la Enfermedad , Aspergilosis Pulmonar Invasiva/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Genotipo , Enfermedades Hematológicas/complicaciones , Humanos , Medición de Riesgo
6.
Talanta ; 172: 68-77, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28602305

RESUMEN

The control of chemical migration from new functionalized food contact materials (FCMs) is a challenge for meeting food safety requirements. The non-intentionally added substances (NIAS) constitute a group of chemicals that are not applied, but may be introduced or formed during the production process of FCMs. This study describes a multi-analytical approach for the evaluation of unknown substances that migrate from FCMs. A case study is presented using a developed polymer consisting of a monolayer film with polylactic acid (PLA), polylimonene (PL) and zinc oxide nanoparticles (ZnO NPs). This approach incorporates the platforms of ICP-MS (inductively coupled plasma mass spectrometry), to determine whether there is transference of ZnO NPs used as antimicrobial agent and, the systems GC-MS and LC-MS (gas / liquid chromatography coupled to a quadrupole orbitrap mass spectrometer) for the characterization of the chemical structure of NIAS using the molecular mass and specific features of mass fragmentation. The screening of unknown compounds comprised retrospective analysis and data processing using both, a mass spectral library and databases, for GC and LC data, respectively. This approach has provided the tentative identification and quantification of seven NIAS, 3 by GC (Tripropylene glycol diacrylate, 10-Heneicosene and α-Tocopherol acetate) and 4 by LC (N,N-Diethyldodecanamide, N-[(9Z)-9-Octadecen-1-yl]acetamide, 1-Palmitoylglycerol and Glycerol stearate). This migration study was carried out according to the standard protocols established by EU regulation for FCMs.


Asunto(s)
Cromatografía Liquida/métodos , Contaminación de Alimentos/análisis , Embalaje de Alimentos , Cromatografía de Gases y Espectrometría de Masas/métodos , Nanotecnología/métodos , Inocuidad de los Alimentos , Nanocompuestos/química , Nanopartículas/química , Polímeros/química , Óxido de Zinc/química
7.
J Chromatogr A ; 1501: 107-116, 2017 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-28434710

RESUMEN

In the last 10 years, the majority of the pesticide food control laboratories moved from GC-MS to GC-MS/MS as the preferred analytical technique to address GC amenable compounds. The main reason for this change was the negative impact on the single stage GC-MS analysis caused by the interference from coeluting matrix compounds. The new development of gas chromatography coupled to high resolution accurate mass spectrometry (GC-HRAMS) provides opportunities to overcome such matrix interferences as a result of its much higher selectivity; allowing laboratories to carry out full-scan analysis covering the most exigent analytical performance criteria. The aim of this work is the evaluation of the main analytical performance parameters for the multiresidue screening of pesticide residues by a gas chromatography-Orbitrap™ mass spectrometer in fruits and vegetables. Electron ionization and full-scan high resolution mass spectrometry was selected for this evaluation. Mass resolving power, selectivity, sensitivity, analyte identification and database generation are discussed in light of the analysis of various commodities and a large scope of pesticides. The selected operational conditions provided optimal mass accuracy, within ±1mDa and achieved LOQs of 10µg/kg or lower for practically all the selected pesticides and commodities. Applicability for quantitative residue analysis was verified by the validation of the 210 pesticides in four matrices (tomato, apple, leek and orange). The performance of the GC-EI-full scan Orbitrap HRAMS developed method was confirmed with the analysis of 102 real samples providing good results.


Asunto(s)
Frutas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Residuos de Plaguicidas/química , Verduras/química , Citrus sinensis/química , Contaminación de Alimentos/análisis , Solanum lycopersicum/química , Malus/química , Espectrometría de Masas/métodos , Espectrometría de Masas en Tándem
8.
Environ Sci Pollut Res Int ; 23(6): 5019-29, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25382501

RESUMEN

In the last years, several scientific studies have shown that carbamazepine (CBZ) is one of the most frequently detected pharmaceutical in aquatic environment. However, little data is available on its detection and its transformation products (TPs) in marine water. The use of polar organic chemical integrative sampling (POCIS) passive samplers as a semi-quantitative and qualitative tool for screening of pharmaceuticals and TPs in seawater has been studied. Furthermore, the uptake rates of the target compounds were also determined under laboratory experiments to characterize the levels accumulated in devices. The results confirmed the presence of residues of anticonvulsant CBZ as well as some of its main metabolites, over a 1-year monitoring campaign carried out in French coast on the Mediterranean Sea. The work reports for the first time the presence of two TPs (10,11-dihydro-10,11-trans-dihydroxycarbamazepine (TRANS) and 10-hydroxy-10,11-dihydrocarbamazepine (10OH)) in marine water. The results contribute in assessing the environmental and human health risk of pharmaceuticals on coastal areas.


Asunto(s)
Anticonvulsivantes/análisis , Carbamazepina/análisis , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Anticonvulsivantes/metabolismo , Carbamazepina/análogos & derivados , Carbamazepina/metabolismo , Humanos , Mar Mediterráneo , Agua de Mar , Contaminantes Químicos del Agua/metabolismo
9.
Sci Total Environ ; 532: 564-70, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26102056

RESUMEN

Aquatic organisms are exposed to pharmaceuticals present in natural waters, but few data are available on the accumulation of these substances in such organisms. The present study evaluated the in vivo bioconcentration of two anticonvulsants--carbamazepine (CBZ) and 10-hydroxy-10,11-dihydro-carbamazepine (10 OH)--in marine mussels (Mytilus galloprovincialis) exposed to nominal 10 µg L(-1) concentrations for one week. The bioconcentration factors (BCFs) were 3.9 and 4.5 L kg(-1) dry weight (dw) for CBZ and 10 OH, respectively. CBZ accumulation reached an average tissue concentration of 29.3 ± 4.8 ng g(-1) dw, and 10 OH accumulated up to 40.9 ± 4.6 ng g(-1) dw in tissues within one week, showing first-order kinetics. BCF obtained with linear QSAR models correctly estimated the CBZ bioconcentration and overestimated the 10 OH bioconcentration to some extent. The detection of two metabolites (carbamazepine-10,11-epoxide and acridine) among the five sought suggested an active metabolism for CBZ. In contrast, none of the 10 OH metabolites were detected in mussels exposed to 10 OH. CBZ showed higher accumulation in the digestive gland, where some relevant metabolites were detected, than in other studied tissues. The implication of those findings on field biomonitoring is discussed.


Asunto(s)
Anticonvulsivantes/metabolismo , Carbamazepina/metabolismo , Monitoreo del Ambiente , Mytilus/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Carbamazepina/análogos & derivados
10.
Food Microbiol ; 44: 185-95, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25084662

RESUMEN

The purpose of this study was to determine the effect of enterocin AS-48, packaged under normal atmosphere (NA), vacuum (VP) or modified atmosphere (MAP) on the shelf life and safety of fresh sardines (Sardina pilchardus) stored at 5 °C. We studied the effect of these hurdles, alone or combined, on the relevant autochthonous bacterial populations. Total volatile basic nitrogen (TVB-N) content was used as indicative of freshness. Levels of biogenic amines cadaverine, putrescine, tyramine, and histamine were also determined. The application of AS-48 did not reduce the mesophilic, psychrotrophic, or Gram negative bacteria viable cell counts under any of the storage conditions tested. AS-48 did cause significant reductions in viable staphylococci counts, especially under VP. In sardines under NA treated with AS-48, the populations of histamine- and tyramine-forming total and lactic acid bacteria (LAB) showed no significant reductions. MAP or VP with AS-48 allowed reductions (significant at some storage times) in histamine- and tyramine-forming LAB. The TVB-N content was also reduced under normal atmosphere and, especially, in sardines stored under MAP. The most interesting results are those concerning the decrease (by several fold) in the levels of the biogenic amines cadaverine, putrescine, tyramine, and histamine determined after treatment with AS-48.


Asunto(s)
Antibacterianos/farmacología , Bacteriocinas/farmacología , Productos Pesqueros/análisis , Aditivos Alimentarios/análisis , Conservación de Alimentos/métodos , Animales , Antibacterianos/análisis , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Bacteriocinas/análisis , Productos Pesqueros/microbiología , Peces , Aditivos Alimentarios/farmacología , Inocuidad de los Alimentos , Almacenamiento de Alimentos
11.
Sci Total Environ ; 493: 162-9, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-24946029

RESUMEN

The UV filters and musk fragrances have come into focus because these compounds are contained and increasingly used not only in sunscreen products but also in many products of daily use, such as cosmetics, skin creams, plastics or varnish. In view of this, the main objective of the present work was to develop and validate a method for the determination of three UV filters, two UV stabilizers and four musks in mussel samples (Mytilus galloprovincialis). The procedure combined a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction method with an analysis by gas chromatography-tandem mass spectrometry (GC-MS/MS). The methodology allowed the determination of target analytes at trace concentration levels (ng/g), with mean recoveries ranging from 91 to 112%. A monitoring study was conducted in four beaches in the Portuguese coast which are impacted by recreational activities and outflow of treated waste water effluents in rivers. The results are used to assess the occurrence of UV filters in comparison with UV stabilizers and musk fragrances which indicate other activities than bathing.


Asunto(s)
Bivalvos/metabolismo , Monitoreo del Ambiente , Perfumes/metabolismo , Protectores Solares/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Cromatografía de Gases y Espectrometría de Masas
12.
Environ Sci Pollut Res Int ; 21(21): 12583-604, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24952251

RESUMEN

This study describes a comprehensive strategy for detecting and elucidating the chemical structures of expected and unexpected transformation products (TPs) from chemicals found in river water and effluent wastewater samples, using liquid chromatography coupled to electrospray ionization quadrupole-time-of-flight mass spectrometer (LC-ESI-QTOF-MS), with post-acquisition data processing and an automated search using an in-house database. The efficacy of the mass defect filtering (MDF) approach to screen metabolites from common biotransformation pathways was tested, and it was shown to be sufficiently sensitive and applicable for detecting metabolites in environmental samples. Four omeprazole metabolites and two venlafaxine metabolites were identified in river water samples. This paper reports the analytical results obtained during 2 years of monitoring, carried out at eight sampling points along the Henares River (Spain). Multiresidue monitoring, for targeted analysis, includes a group of 122 chemicals, amongst which are pharmaceuticals, personal care products, pesticides and PAHs. For this purpose, two analytical methods were used based on direct injection with a LC-ESI-QTOF-MS system and stir bar sorptive extraction (SBSE) with bi-dimensional gas chromatography coupled with a time-of-flight spectrometer (GCxGC-EI-TOF-MS).


Asunto(s)
Plaguicidas/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Cromatografía de Gases/métodos , Cromatografía Liquida/métodos , Monitoreo del Ambiente , Límite de Detección , Peso Molecular , Omeprazol/análisis , Omeprazol/química , España , Espectrometría de Masa por Ionización de Electrospray
13.
J Environ Sci Health B ; 49(8): 557-68, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24901959

RESUMEN

A rapid, sensitive, accurate and reliable multiresidue method for the identification and quantification of 210 relevant pesticides in four representative fruit and vegetable commodities (tomato, potato, spring onion and orange) has been developed and validated by gas chromatography in tandem with triple quadrupole mass spectrometry. The method has been fully validated and applied to 292 samples from different countries. Prior to instrumental analysis, an extraction procedure based on a sample extraction of multiclass analytes, using the ethyl acetate method was employed. Mass spectrometric conditions were individually optimized for each compound in the selected reaction monitoring (SRM) mode to achieve maximum sensitivity. The pesticides were separated in less than 25 min. This was followed by an exhaustive control of the retention times. The Retention Time Locking Method was applied, working at a constant pressure throughout the analysis. System maintenance was reduced by using a purged capillary flow device that provided backflush capabilities by reversing column flow immediately after elution of the last compound of interest. Istotopically labelled internal standards were employed to improve the quality of the analytical results.


Asunto(s)
Tecnología de Alimentos/métodos , Frutas/química , Cromatografía de Gases y Espectrometría de Masas , Residuos de Plaguicidas/análisis , Verduras/química , Citrus sinensis/química , Solanum lycopersicum/química , Cebollas/química , Solanum tuberosum/química
14.
Arch Microbiol ; 196(7): 481-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24760293

RESUMEN

Magnetotactic bacteria are a diverse group of prokaryotes that biomineralize intracellular magnetosomes, composed of magnetic (Fe3O4) crystals each enveloped by a lipid bilayer membrane that contains proteins not found in other parts of the cell. Although partial roles of some of these magnetosome proteins have been determined, the roles of most have not been completely elucidated, particularly in how they regulate the biomineralization process. While studies on the localization of these proteins have been focused solely on Magnetospirillum species, the goal of the present study was to determine, for the first time, the localization of the most abundant putative magnetosome membrane protein, MamC, in Magnetococcus marinus strain MC-1. MamC was expressed in Escherichia coli and purified. Monoclonal antibodies were produced against MamC and immunogold labeling TEM was used to localize MamC in thin sections of cells of M. marinus. Results show that MamC is located only in the magnetosome membrane of Mc. marinus. Based on our findings and the abundance of this protein, it seems likely that it is important in magnetosome biomineralization and might be used in controlling the characteristics of synthetic nanomagnetite.


Asunto(s)
Alphaproteobacteria/metabolismo , Alphaproteobacteria/ultraestructura , Proteínas Bacterianas/metabolismo , Magnetosomas/metabolismo , Microscopía Inmunoelectrónica , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Escherichia coli/metabolismo , Magnetosomas/ultraestructura
15.
Anal Bioanal Chem ; 406(2): 601-10, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24306328

RESUMEN

Coastal areas are subject to growing pressures and impacts because of the increase in human activities. Lipophilic organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) or polychlorinated biphenyls (PCBs), have been monitored for decades within monitoring programs. However, until now, little information on the detection of so-called "emerging contaminants" such as hydrophilic organic compounds in the marine environment and no data on its metabolites or transformation products in marine organisms is available. In this report, a sensitive analytical methodology for identification and confirmation of venlafaxine (VEN) residues and five of its main metabolites in the marine mussels Mytilus galloprovincialis was validated. The sample preparation procedure was based on the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) approach. An analytical method was developed to quantify these compounds at trace levels by liquid chromatography coupled to high-resolution mass spectrometry. The method was then applied to marine mussels collected from the Mediterranean Sea in southeastern France. Residues of the antidepressant VEN were occasionally detected at ng/g dw level. In addition, the approach allowed us to identify several transformation products in the analyzed samples. N-desmethylvenlafaxine (NDV) was the most frequently detected metabolite followed by N,O-di-desmethylvenlafaxine (NODDV).


Asunto(s)
Bivalvos/química , Ciclohexanoles/análisis , Contaminantes Químicos del Agua/análisis , Animales , Biotransformación , Bivalvos/metabolismo , Cromatografía Liquida , Ciclohexanoles/metabolismo , Humanos , Espectrometría de Masas , Mar Mediterráneo , Clorhidrato de Venlafaxina , Contaminantes Químicos del Agua/metabolismo
16.
J Chromatogr A ; 1305: 27-34, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-23891381

RESUMEN

Environmental field studies have shown that carbamazepine (Cbz) is one of the most frequently detected human pharmaceuticals in different aquatic compartments. However, little data is available on the detection of this substance and its transformation products in aquatic organisms. This study was thus mainly carried out to optimize and validate a simple and sensitive analytical methodology for the detection, characterization and quantification of Cbz and oxcarbazepine (Ox), two anticonvulsants, and six of their main transformation products in marine mussels (Mytilus galloprovincialis). A modified QuEChERS extraction method followed by analysis with liquid chromatography coupled to high resolution mass spectrometry (HRMS) was used. The analyses were performed using two-stage fragmentation to reveal the different fragmentation pathways that are highly useful for the identification of isomeric compounds, a common problem when several transformation products are analyzed. The developed analytical method allowed determination of the target analytes in the lower ng/g concentration levels. The mean recovery ranged from 67 to 110%. The relative standard deviation was under 11% in the intra-day and 18% in the inter-day analyses, respectively. Finally, the method was applied to marine mussel samples collected from Mediterranean Sea cultures in southeastern France. Residues of the psychiatric drug Cbz were occasionally found at levels up to 3.5ng/g dw. Lastly, in this study, other non-target compounds, such as caffeine, metoprolol, cotinine and ketoprofen, were identified in the real samples analyzed.


Asunto(s)
Anticonvulsivantes/análisis , Bivalvos/química , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/análisis , Animales , Anticonvulsivantes/farmacocinética , Límite de Detección , Contaminantes Químicos del Agua/farmacocinética
17.
J Chromatogr A ; 1297: 17-28, 2013 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-23726087

RESUMEN

The present paper describes a solid-phase extraction by packed multi-walled carbon nanotubes, followed by liquid chromatography-mass spectrometry, method for the determination of some of the most consumed drugs including four ß-blockers and eight non-steroidal anti-inflammatory drugs, in river and wastewater samples. High extraction efficiency was found for most drugs due to the large specific surface area and high adsorption capacity of this nanomaterial compared with other conventional solid-phase extraction sorbents, and matrix effect was present only for two of the twelve studied drugs. Only 20mg of carbon nanotubes was enough to preconcentrate the analytes with recoveries from 68% to 107% for most of them. The pharmaceuticals were analyzed by liquid chromatography coupled to a hybrid triple quadrupole-linear ion trap-mass spectrometer at ultra-trace levels. Data acquisition was carried out in selected reaction monitoring mode, using two transitions for simultaneous identification and quantification of the analytes. Additionally, an information dependent acquisition scan was performed to carry out the identification of those analytes whose second transition was absent or was present at low intensity. The analytical performance of the whole method was evaluated in two environmental water matrices (river and wastewaters). Matrix effect was not found in river water, quantitation being carried out with calibration graphs built with solvent based standard. On the contrary, matrix effect was present in wastewater for some of the target drugs and, therefore, quantitation was carried out using the standard addition method. Limits of detection and quantitation in river waters were in the range of 9-36 and 23-121ngL(-1), respectively and the relative standard deviation of the full method was less than 17%. The proposed methodology was applied to the analysis of three river water and two wastewater (influent and effluent) samples, all of them from Almería (Spain). Some pharmaceuticals were found in river water at concentration levels near to or lower than their quantitation limits, whereas the most consumed pharmaceuticals were found at high concentration levels in influent wastewater and were not detected or were found at lower levels in the effluent wastewater sample.


Asunto(s)
Cromatografía Liquida/métodos , Nanotubos de Carbono/química , Preparaciones Farmacéuticas/análisis , Ríos/química , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Preparaciones Farmacéuticas/aislamiento & purificación , Reproducibilidad de los Resultados , Contaminantes Químicos del Agua/aislamiento & purificación
18.
Int J Food Microbiol ; 163(2-3): 136-45, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23558197

RESUMEN

A set of 80 Lactobacillus strains (36 Lactobacillus plantarum and 44 Lactobacillus paracasei) isolated from Spanish farmhouse cheeses have been studied as to their functional and safety properties and their survival under gut-related conditions. None of these 80 Lactobacillus strains were able to hydrolyse starch. A high percentage of L. plantarum and L. paracasei strains were, however, capable of hydrolysing casein (86.1% and 68.2% respectively). For the other characteristics investigated, L. plantarum strains generally had more positive responses than L. paracasei. The latter strains tested negative for most of these characteristics, with the exception of stachyose hydrolysis, which was positive in six strains of L. paracasei. A high percentage (91.7%) of L. plantarum produced haemo-dependent catalase. Phytase was present in 10 L. plantarum and in 2 L. paracasei. Most L. plantarum (83.3%) but no L. paracasei hydrolysed bile salts. All strains were completely resistant to a challenge of pH3, but many showed a loss of viability after a subsequent exposure to 0.3% oxgall; in fact, only one L. paracasei strain and 33 L. plantarum strains (91.67%) were tolerant to both stresses. L. plantarum Mb25 and L. plantarum Mb26 were the most adherent to Caco-2 cells (adherence percentages of 36 and 7% respectively). These two strains were also the most adherent to HeLa 229 cells, with 19.3 and 16.0% adhesion respectively. The Mb26 strain inhibited the adhesion of Listeria monocytogenes to Caco-2 cells when added simultaneously to Listeria and also when added 1h before the pathogen (21.0% and 51.6% adhesion inhibition, respectively). Production of H2O2 was detected in 38.9% of L. plantarum strains and in 9.1% of L. paracasei. Twelve L. plantarum and eight L. paracasei strains produced bacteriocin-like inhibitors. PCR amplifications of several plantaricin genes suggest that all the bacteriocinogenic strains may produce plantaricin E/F and some may also manufacture the plantaricin J/K. The nine L. plantarum strains assayed for antibiotic resistance were resistant to ciprofloxacin (MIC>2 µg/ml), vancomycin (MIC>16 µg/ml), and teicoplanin (MIC>16 µg/ml). Moreover, some strains showed intermediate resistance to penicillin, tetracycline, rifampicin, and levofloxacin. We conclude that farmhouse cheeses are good sources of biotechnologically relevant lactobacilli and that the L. plantarum species shows better biotechnological properties than L. paracasei. This can be deduced from the finding of a high percentage of strains of L. plantarum that exhibit remarkable functional and inhibitory properties and high abilities to survive in gut-related conditions, which can be further developed for biotechnological applications.


Asunto(s)
Queso/microbiología , Microbiología de Alimentos , Tracto Gastrointestinal/microbiología , Lactobacillus/fisiología , Animales , Antibacterianos/farmacología , Bacteriocinas/genética , Células CACO-2 , Cabras , Células HeLa , Humanos , Peróxido de Hidrógeno/farmacología , Lactobacillus/enzimología , Lactobacillus/genética , Lactobacillus/aislamiento & purificación , Listeria monocytogenes/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana
19.
J Chromatogr A ; 1256: 80-8, 2012 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-22901300

RESUMEN

A new approach for the analysis of pharmaceuticals (target and non-target) in water by LC-QTOF-MS is described in this work. The study has been designed to assess the performance of the simultaneous quantitative screening of target compounds, and the qualitative analysis of non-target analytes, in just one run. The features of accurate mass full scan mass spectrometry together with high MS/MS spectral acquisition rates - by means of information dependent acquisition (IDA) - have demonstrated their potential application in this work. Applying this analytical strategy, an identification procedure is presented based on library searching for compounds which were not included a priori in the analytical method as target compounds, thus allowing their characterization by data processing of accurate mass measurements in MS and MS/MS mode. The non-target compounds identified in river water samples were ketorolac, trazodone, fluconazole, metformin and venlafaxine. Simultaneously, this strategy allowed for the identification of other compounds which were not included in the library by screening the highest intensity peaks detected in the samples and by analysis of the full scan TOF-MS, isotope pattern and MS/MS spectra - the example of loratadine (histaminergic) is described. The group of drugs of abuse selected as target compounds for evaluation included analgesics, opioids and psychostimulants. Satisfactory results regarding sensitivity and linearity of the developed method were obtained. Limits of detection for the selected target compounds were from 0.003 to 0.01 µg/L and 0.01 to 0.5 µg/L, in MS and MS/MS mode, respectively - by direct sample injection of 100 µL.


Asunto(s)
Preparaciones Farmacéuticas/análisis , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/análisis , Cromatografía Liquida , Ríos
20.
J Evol Biol ; 25(9): 1779-91, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22805098

RESUMEN

Potentially, pathogenic bacteria are one of the main infective agents against which a battery of chemical and physical barriers has evolved in animals. Among these are the secretions by the exocrine uropygial gland in birds. The antimicrobial properties of uropygial secretions may prevent colonization and growth of microorganisms on feathers, skin and eggshells. However, uropygial gland secretions also favour the proliferation of feather mites that feed on secretions and microorganisms living on feathers that would otherwise reach eggshells during incubation if not consumed by feather mites. Therefore, at the interspecific level, uropygial gland size (as an index of volume of uropygial secretion) should be positively related to eggshell bacterial load (i.e. the risk of egg infection), whereas eggshell bacterial loads may be negatively related to abundance of feather mites eating bacteria. Here, we explore these previously untested predictions in a comparative framework using information on eggshell bacterial loads, uropygial gland size, diversity and abundance of feather mites and hatching success of 22 species of birds. The size of the uropygial gland was positively related to eggshell bacterial loads (mesophilic bacteria and Enterobacteriaceae), and bird species with higher diversity and abundance of feather mites harboured lower bacterial density on their eggshells (Enterococcus and Staphylococcus), in accordance with the hypothesis. Importantly, eggshell bacterial loads of mesophilic bacteria, Enterococcus and Enterobacteriaceae were negatively associated with hatching success, allowing us to interpret these interspecific relationships in a functional scenario, where both uropygial glands and mutualistic feather mites independently reduce the negative effects of pathogenic bacteria on avian fitness.


Asunto(s)
Carga Bacteriana , Evolución Biológica , Aves/anatomía & histología , Glándulas Exocrinas/anatomía & histología , Glándulas Exocrinas/metabolismo , Ácaros/fisiología , Animales , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/veterinaria , Enfermedades de las Aves/microbiología , Aves/clasificación , Aves/microbiología , Peso Corporal , Ecosistema , Cáscara de Huevo/microbiología , Cáscara de Huevo/fisiología , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/patogenicidad , Enterococcus/crecimiento & desarrollo , Enterococcus/patogenicidad , Europa (Continente)/epidemiología , Plumas/microbiología , Aptitud Genética , Tamaño de los Órganos/fisiología , Filogenia , Dinámica Poblacional , Especificidad de la Especie , Staphylococcus/crecimiento & desarrollo , Staphylococcus/patogenicidad , Simbiosis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...