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1.
Phytother Res ; 35(2): 1089-1098, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32929801

RESUMO

Vaccinium myrtillus berry extract (VME) and a recombined standard mixture (RSM) of its main native phenolic compounds were investigated for cell growth inhibition and pro-apoptotic activity on hormone-dependent (LNCaP) and hormone-independent (PC3 and DU-145) prostate cancer (PCa) cell lines. Normal prostate epithelial cells (PrEC) were also studied in comparison. VME hindered anchorage-dependent PCa cell proliferation in a dose-dependent manner, that is, at 1/800 (v/v) dilution for LNCaP and PC3, and 1/100 (v/v) dilution for DU-145 (corresponding to 14.15 and 113.2 µg cyanidin-3-O-glucoside equivalents per ml of culture medium), respectively. VME had a growth inhibitory effect towards PrEC at the same dilution of DU-145 cells although the IC50 values indicated that PrEC are more resistant than PCa cell lines. VME also reduced the anchorage-independent growth of PCa cells. The study of the apoptotic profile (i.e., non-apoptotic, early apoptotic, late apoptotic and necrotic cells) evidenced that the apoptotic rate (early+late) was statistically higher in all three cell lines exposed to VME compared to control. Anchorage-dependent and anchorage-independent growth inhibition of RSM was very similar to that displayed by VME. Moreover, RSM exerted its growth inhibitory effect also under hypoxia, the latter representing a biological condition known to sustain PCa proliferation and aggressiveness.


Assuntos
Antocianinas/química , Frutas/química , Extratos Vegetais/química , Polifenóis/química , Neoplasias da Próstata/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Masculino , Vaccinium myrtillus
2.
J Chromatogr A ; 1621: 461038, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32199674

RESUMO

A QuEChERS method was optimized and validated for the LC-MS/MS analysis of perfluoro-n-pentanoic acid (PFPeA), perfluoro-1-butanesulfonic acid (PFBuS), perfluoro-n-hexanoic acid (PFHxA), perfluoro-n-heptanoic acid (PFHpA), perfluoro-1-hexanesulfonic acid (PFHxS), perfluoro-n-octanoic acid (PFOA), perfluoro-n-nonanoic acid (PFNA), perfluoro-1-octanesulfonic acid (PFOS) and perfluoro-n-decanoic acid (PFDA) in freeze-dried strawberry and olive, as model fruits characterized by very different chemical compositions. The method was evaluated for apparent recovery, intra-day and inter-day precision, matrix effect and recovery. The method optimized for strawberry provided for most compounds absolute values of matrix effect (|ME%|) ≤ 11%, except for PFHxA, which showed a signal suppression of 22%. The extraction efficiency was tested at the spike levels 500-5000 pg/g d.w. for PFPeA, PFBuS, and PFHxA, and 100-1000 pg/g d.w. for the other target analytes, evidencing as a whole recoveries in the range of 65-89%. For olive fruits, due to their high fat content, an ultrasound-assisted extraction was necessary to obtain an efficient sample disgregation so as to increase the extraction yield and its precision. Moreover, a d-SPE clean-up with GCB allowed to achieve |ME%| ≤ 8% (except for PFBuS, which showed a signal enhancement of 19%) and recoveries calculated at the aforementioned spike levels were in the range 75-97%. The two methods provided very good linearity (R2 ≥ 0.9984) from 10,000 pg/g down to compound specific quantification limits, which were included in the ranges of 2.9-393 pg/g and 2.6-127 pg/g for strawberry and olive fruit, respectively. The methods were applied to the analysis of PFAAs in strawberry and olive fruits commercially available in two Italian supermarkets, as well as obtained under irrigation with various treated wastewaters (TWWs), evidencing in both cases a higher PFAAs occurrence in olives than in strawberry. However, PFAAs concentrations determined in the investigated fruit matrixes were quite low, being their sum 1.9 ng/g d.w. in the worst case (i.e. olive fruits grown under irrigation with TWWs).


Assuntos
Cromatografia Líquida/métodos , Fluorocarbonos/análise , Fragaria/química , Frutas/química , Olea/química , Espectrometria de Massas em Tandem/métodos , Irrigação Agrícola , Produtos Agrícolas/química , Águas Residuárias
3.
Sci Total Environ ; 708: 135217, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31810702

RESUMO

Three biochars were produced using sawdust from waste biomass, via a simple pyrolysis thermal conversion at 450, 650, and 850 °C (BC450, BC650, and BC850), without any activation process. These materials, together with vegetal and mineral commercial activated carbons (VAC and MAC), were characterized for their elemental composition, Brunauer-Emmett-Teller surface area, t-plot microporosity and Barrett-Joyner-Halenda mesoporosity. Moreover, iodine, phenol and methylene blue porosity indexes were measured. The materials were also evaluated for their pH of the point of zero charge, as well as near-surface chemical composition and surface functionality by means of X-ray photoelectron and Fourier-transform infrared spectroscopy. Ash content, water-extractable metals and polycyclic aromatic hydrocarbons (PAHs) were also determined. BC650 showed a much higher surface area (319 m2 g-1) compared to BC450 (102 m2 g-1), as well as an increase in aromatization and the residual presence of functional polar groups. BC850 exhibited a loss of polar and aromatic groups, with the dominance of graphitic carbon and the highest value of surface area (419 m2 g-1). Biochars comply with the EN 12915-1/2009 limits for metal and PAH release in water treatment. Biochars and MAC were tested using Langmuir and Freundlich isotherms for the sorption in real effluent wastewater of a mixture of 14 branched ethoxylated 4-t-octyl and 4-nonylphenols, as well as 4-t-octyl and 4-nonylphenol, the latter representing persistent, endocrine disrupting contaminants, widespread in the effluents from wastewater treatment plants and listed as priority/priority hazardous substances in the Directive 2013/39/EU. Biochars showed a lower sorption efficiency compared to MAC. The best performance was found for BC650 towards the alkylphenols (9-13 times less efficient than the MAC). Considering the lower market price of biochar compared to MAC (estimated as at least 16 times less expensive by a small market survey), the former can be considered more competitive than the latter.


Assuntos
Carvão Vegetal , Adsorção , Fenômenos Químicos , Fenóis , Têxteis , Águas Residuárias
4.
Sci Total Environ ; 674: 36-48, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31003086

RESUMO

In this work the occurrence and fate of polycyclic aromatic hydrocarbons (PAHs), phthalic acid esters (PAEs), mono and diethoxylate alkylphenols (AP1-2EOs) and alkylphenols (APs) have been investigated during a two-weeks period in a facility treating mixed textile-domestic wastewater (Prato, Italy). The wastewater treatment plant (WWTP) consists of primary sedimentation, activated sludge biological oxidation, secondary sedimentation, clariflocculation and ozonation. The sludge is treated within the facility by thickening, dewatering and final incineration, thus providing the almost quantitative removal of the adsorbed micropollutants. Naphthalene (50%), di(2-ethylhexyl) phthalate (74%) and branched 4-nonylphenols (59%) were the individual main representative compounds of each class in the influent wastewater, which showed concentration ranges of 5.6-66, 85-290 and 21-133µg/L for PAHs, PAEs and APs+AP1-2EOs, respectively. The WWTP efficiently removed PAHs, PAEs and APs+AP1-2EOs, providing effluent concentrations of 0.075-0.16ng/L 0.38-9.9µg/L and 0.53-1.4µg/L. All targeted priority and priority-hazardous micropollutants showed effluent concentrations in line with the European environmental quality standards (EQS), even though for di(2-ethylhexyl) phthalate and benzo(a)pyrene after correction for the dilution factor of the recipient. The WWTP performance was evaluated by mass balance, verifying its accuracy by monitoring Pb and Cd as conservative species. The biological treatment sections provided mass losses of 85.5%, 74.5% and 56.8% for APs+AP1-2EOs, PAEs and PAHs, highlighting efficient biotransformation performances of the activated sludge process. However, for the more volatile PAHs (e.g. naphthalene), a significant contribution of stripping cannot be excluded. A remarkable mass loss was also determined in the ozonation stage for PAEs (72.9%) and especially PAHs (97.0%), whereas a lower efficiency was observed for APs+AP1-2EOs (41.3%). The whole plant allowed for obtaining an almost quantitative removal (96.7-98.4%) for all targeted compounds.

5.
Sci Total Environ ; 633: 405-425, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29579652

RESUMO

Contamination of the aquatic environment caused by multiple human activities may exert a negative impact on all living organisms. Several contaminants of emerging concern such as personal care products (PCPs) are continuously released into the aquatic environment where they are biologically active and persistent. This work reviews the current knowledge, provided by papers published after 2010 and indexed by SciFinder, Scopus, and Google search engines, about the determination and occurrence of PCPs in marine biota. Analytical methodologies have been critically reviewed, emphasizing the importance of green and high-throughput approaches and focusing the discussion on the complexity of the solute-matrix interaction in the extraction step, as well as the matrix effect in the instrumental determination. Finally, the worldwide distribution of PCPs is surveyed, taking into account the concentrations found in the same organism in different marine environments. Differences among various world areas have been highlighted, evidencing some critical aspects from an environmental point of view.


Assuntos
Organismos Aquáticos/metabolismo , Cosméticos/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Organismos Aquáticos/química , Cosméticos/metabolismo , Poluentes Químicos da Água/metabolismo , Poluição Química da Água/análise
6.
J Pharm Biomed Anal ; 148: 6-16, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-28946042

RESUMO

A sensitive and reliable analytical method was developed for the simultaneous determination of five phthalate diesters and corresponding monoesters in human milk samples and infant formulas. The method involved a liquid-liquid extraction with a CH2Cl2/CH3OH/NaCl 30% 2/1/0.5 (v/v/v) mixture, the clean-up of the extract by size-exclusion chromatography (swelling and elution solvent: cyclohexane/ethyl acetate 9/1v/v), the derivatization of monoesters by trimethylsilyl-diazomethane and instrumental analysis by gas chromatography coupled with mass spectrometry. Recovery was in the range of 83-115% and precision was found between 9% and 21%. For phthalate diesters, method detection limits (MDLs) ranged from hundreds of ng/kg to 4.2µg/kg on a fresh weight milk (f.w.) basis, depending on blank contribution evaluated in matrix. Lower MDLs (0.03-0.8µg/kg f.w.) were achieved for corresponding monoesters. The proposed method was applied to the determination of target compounds in nine human milk samples and four infant formulas, confirming their presence in all samples. However, a generally higher contamination was assessed in artificial milk than in breast milk samples.


Assuntos
Ésteres/química , Fórmulas Infantis/análise , Leite Humano/química , Ácidos Ftálicos/química , Cromatografia em Gel/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Recém-Nascido , Limite de Detecção , Extração Líquido-Líquido/métodos
7.
Plant Physiol Biochem ; 97: 52-61, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26410575

RESUMO

In this study wild type Nicotiana langsdorffii plants were genetically transformed by the insertion of the rat gene (gr) encoding the glucocorticoid receptor or the rolC gene and exposed to water and heat stress. Water stress was induced for 15 days by adding 20% PEG 6000 in the growth medium, whereas the heat treatment was performed at 50 °C for 2 h, after that a re-growing capability study was carried out. The plant response to stress was investigated by determining electrolyte leakage, dry weight biomass production and water content. These data were evaluated in relation to antiradical activity and concentrations of total polyphenols, selected phenolic compounds and some soluble sugars, as biochemical indicators of metabolic changes due to gene insertion and/or stress treatments. As regards the water stress, the measured physiological parameters evidenced an increasing stress level in the order rolC < gr < WT plants (e.g. about 100% and 50% electrolyte leakage increase in WT and gr samples, respectively) and complied with the biochemical pattern, which consisted in a general decrease of antiradical activity and phenolics, together with an increase in sugars. As regard heat stress, electrolyte leakage data were only in partial agreement with the re-growing capability study. In fact, according to this latter evaluation, gr was the genotype less affected by the heat shock. In this regard, sugars and especially phenolic compounds are informative of the long-term effects due to heat shock treatment.


Assuntos
Regulação da Expressão Gênica de Plantas , Nicotiana/fisiologia , Polifenóis/metabolismo , Água/fisiologia , Metabolismo dos Carboidratos , Desidratação , Resposta ao Choque Térmico , Temperatura Alta , Fenóis/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Estresse Fisiológico , Nicotiana/química , Nicotiana/genética , Transgenes
8.
Anal Bioanal Chem ; 407(4): 1217-29, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25503933

RESUMO

Seven quick, easy, cheap, effective, rugged and safe (QuEChERS)-based procedures, differing in both the extraction and clean-up steps, were investigated for the recovery of bentazone (BTZ), atrazine (ATZ), carbamazepine (CBZ), phenytoin (PNT) and its metabolite 5-(p-hydroxyphenyl-),5-phenylhydantoin (HPPH) from soil. Target analytes were chosen for their extensive use and/or occurrence in soil, as well as for their medium-high polarity characteristics (log K OW values in the range 0.88-2.80), which have been reported as a critical parameter for the recovery from soil with QuEChERS approaches. Liquid chromatography coupled with UV and pulsed amperometric (PA) detection at a glassy carbon electrode was used as instrumental technique. The recovery data obtained within each tested procedure were discussed for each compound investigated, highlighting different behaviour depending on the specific physicochemical characteristics of the analytes. The optimized QuEChERS conditions consisted of the extraction of analytes with CH3CN:H2O 70:30, 5 % CH3COOH, followed by a dispersive solid-phase extraction (d-SPE) clean-up step with C18 sorbent. This method, in which water is directly added to the soil together with acetonitrile and salts, allowed the rehydration step to be avoided, which can be as long as 30 min. Matrix effects were evaluated for both the detection techniques at different concentration levels, and they were below 24 % for both the detection technique used. The recoveries were evaluated at three concentration levels by a matrix-matched calibration and were in the ranges of 83-113 % (relative standard deviations (RSD) ≤ 14 %) and 88-109 % (RSD ≤ 11 %) for UV and PA detection, respectively, highlighting very good performances of the method, even for the more polar analytes. Method detection limits ranged from 4 µg/kg (BTZ) to 493 µg/kg (PNT) and from 4 µg/kg (HPPH) to 11 µg/kg (BTZ) for UV and PA detection, respectively. The method was finally compared with a microwave-assisted extraction procedure which provided less satisfactory extraction performances than the optimized QuEChERS procedure.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Técnicas Eletroquímicas/métodos , Recuperação e Remediação Ambiental/métodos , Herbicidas/análise , Preparações Farmacêuticas/análise , Poluentes do Solo/análise , Herbicidas/isolamento & purificação , Preparações Farmacêuticas/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Extração em Fase Sólida/métodos
9.
Anal Bioanal Chem ; 406(17): 4089-116, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24770804

RESUMO

Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) is an extraction and clean-up technique originally developed for recovering pesticide residues from fruits and vegetables. Since its introduction, and until December 2013, about 700 papers have been published using the QuEChERS technique, according to a literature overview carried out using SciFinder, Elsevier SciVerse, and Google search engines. Most of these papers were dedicated to pesticide multiresidue analysis in food matrices, and this topic has been thoroughly reviewed over recent years. The QuEChERS approach is now rapidly developing beyond its original field of application to analytes other than pesticides, and matrices other than food, such as biological fluids and non-edible plants, including Chinese medicinal plants. Recently, the QuEChERS concept has spread to environmental applications by analyzing not only pesticides but also other compounds of environmental concern in soil, sediments, and water. To the best of our knowledge, QuEChERS environmental applications have not been reviewed so far; therefore, in this contribution, after a general discussion on the evolution and changes of the original QuEChERS method, a critical survey of the literature regarding environmental applications of conventional and modified QuEChERS methodology is provided. The overall recoveries obtained with QuEChERS and other extraction approaches (e.g., accelerated solvent extraction, ultrasonic solvent extraction, liquid/solid extraction, and soxhlet extraction) were compared, providing evidence for QuEChERS higher recoveries for various classes of compounds, such as biopesticides, chloroalkanes, phenols, and perfluoroalkyl substances. The role of physicochemical properties of soil (i.e., clay and organic carbon content, as well as cation exchange capacity) and target analytes (i.e., log KOW, water solubility, and vapor pressure) were also evaluated in order to interpret recovery and matrix effect data.


Assuntos
Fracionamento Químico/métodos , Poluentes Ambientais/isolamento & purificação , Compostos Orgânicos/isolamento & purificação , Resíduos de Praguicidas/isolamento & purificação , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Compostos Orgânicos/análise , Resíduos de Praguicidas/análise
10.
J Hazard Mater ; 262: 394-403, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24061217

RESUMO

Chromium accumulation, dry weight (DW) biomass yield, water content and concentrations of some selected phenolic compounds and carbohydrates were determined in root and shoot of Nicotiana langsdorffii, either wild type (WT) or genetically modified by the insertion of GR and rolC genes, in response to the presence of Cr(VI) in the growth medium. A biomass decrease was observed for WT plants, but not for GR and rolC transformations, in response to Cr(VI) in the growth medium, highlighting a stress situation only in WT line. Shoot chromium concentrations were in all cases about 300 mg kg(-1) DW. In root higher concentrations were found in rolC than in GR and WT (3843, 2600 and 2751 mg kg(-1) DW, respectively). Based on the DW biomass, GR and WT accumulated higher chromium quantities than rolC, both in root (330 and 424 versus 85 µg Cr per plant) and shoot (282 and 275 versus 121 µg Cr per plant). Therefore, GR should be preferred to WT as a promising candidate for chromium phytoremediation. Metabolic shifts of sugars and phenolics were generally observed in response to either gene insertions or exposure to Cr(VI), being the latter more related to the resistance to Cr(VI) than the former.


Assuntos
Metabolismo dos Carboidratos , Cromo/metabolismo , Nicotiana/metabolismo , Fenóis/metabolismo , Biomassa , Plantas Geneticamente Modificadas , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento
11.
Methods Mol Biol ; 970: 29-43, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23283769

RESUMO

An up-to-date overview of thin-layer chromatography (TLC) techniques for chiral separations of various significant and/or recent examples of enantioresolutions is reported. Furthermore, examples for chiral separations obtained on achiral commercially available C18 TLC plates are described in detail. These include the enantioseparation of methylthiohydantoin-phenylalanine and methylthiohydantoin-tyrosine using hydroxyethyl-ß-cyclodextrin as mobile phase additive and the separation of the enantiomers of warfarin and p-chlorowarfarin using bovine serum albumin as mobile phase additive.


Assuntos
Cromatografia em Camada Fina/métodos , Animais , Bovinos , Celulose/análise , Celulose/química , Impressão Molecular/métodos , Fenilalanina/análise , Fenilalanina/química , Polímeros/análise , Polímeros/química , Soroalbumina Bovina/análise , Soroalbumina Bovina/metabolismo , Tioidantoínas/análise , Tioidantoínas/química , Tirosina/análise , Tirosina/química , Varfarina/análise , Varfarina/química , beta-Ciclodextrinas/análise , beta-Ciclodextrinas/metabolismo
12.
Anal Bioanal Chem ; 405(2-3): 533-54, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23161065

RESUMO

The current state of chiral separations by thin-layer chromatography using chiral stationary phases is reviewed. Both stationary phases essentially constituted by the chiral selector and those obtained by the impregnation of achiral plates with appropriate chiral selectors are described. Particular attention is paid to commercial and non-commercial cellulose and cellulose-derivative plates, as well as commercially available Chiralplate™, which are currently the most widely used. Some of the most important results obtained to date are reported and discussed; the examples provided illustrate the very wide range of structurally different solutes that can be readily resolved into their enantiomers by planar chromatographic methods. Special attention is paid to the discussion of the retention and resolution factors that influence chiral discrimination. The quantitative analysis of enantiomers is also discussed, especially from the point of view of determination of enantiomeric purity.


Assuntos
Aminoácidos/química , Cromatografia em Camada Fina/métodos , Celulose/química , Cromatografia em Camada Fina/instrumentação , Estereoisomerismo
13.
J Mass Spectrom ; 47(9): 1207-20, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22972789

RESUMO

High-performance liquid chromatography coupled with ion spray mass spectrometry in the tandem mode with both negative and positive ionization was used for investigating a variety of polyphenolic compounds in four genotypes of Fragaria vesca berries. About 60 phenolic compounds belonging to the compound classes of phenolic acids, ellagitannins, ellagic acid derivatives, flavonols, monomeric and oligomeric flavanols, dihydrochalcones and anthocyanins were reported, providing for the first time a quite complete picture of polyphenolic composition of F. vesca berries. Some of the polyphenols herein investigated, such as a tris-galloyl-hexahydroxydiphenoyl-hexose, two castalagin/vescalagin-like isomers and peonidin-malonylglucoside, were described for the first time. Principal component analysis applied on original HPLC-MS/MS data, acquired in multiple reaction monitoring mode, successfully discriminated the four investigated cultivars on the basis of their polyphenolic composition, highlighting the fundamental role of mass spectrometry for food characterization.


Assuntos
Ácidos Cumáricos/análise , Flavonoides/análise , Fragaria/química , Frutas/química , Hidroxibenzoatos/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise de Componente Principal , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
14.
J Hazard Mater ; 199-200: 209-16, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22104764

RESUMO

In this study, during a two-year period, we investigated the fate of hexavalent and trivalent chromium in a full-scale subsurface horizontal flow constructed wetland planted with Phragmites australis. The reed bed operated as post-treatment of the effluent wastewater from an activated sludge plant serving the textile industrial district and the city of Prato (Italy). Chromium speciation was performed in influent and effluent wastewater and in water-suspended solids, at different depths and distances from the inlet; plants were also analyzed for total chromium along the same longitudinal profile. Removals of hexavalent and trivalent chromium equal to 72% and 26%, respectively were achieved. The mean hexavalent chromium outlet concentration was 1.6 ± 0.9 µg l(-1) and complied with the Italian legal limits for water reuse. Chromium in water-suspended solids was in the trivalent form, thus indicating that its removal from wastewater was obtained by the reduction of hexavalent chromium to the trivalent form, followed by accumulation of the latter inside the reed bed. Chromium in water-suspended solids was significantly affected by the distance from the inlet. Chromium concentrations in the different plant organs followed the same trend of suspended solids along the longitudinal profile and were much lower than those found in the solid material, evidencing a low metal accumulation in P. australis.


Assuntos
Cromo/análise , Resíduos Industriais , Reciclagem , Indústria Têxtil , Poluentes Químicos da Água/isolamento & purificação , Áreas Alagadas , Esgotos
15.
Ann Chim ; 95(9-10): 629-41, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16342735

RESUMO

A sensitive and reliable analytical method was developed for the simultaneous extraction of PAHs and total fats and their determination in the human milk. The method involved a liquid-liquid extraction of PAHs and fats, followed by the gravimetric determination of the latter. PAHs were separated from lipids by size exclusion chromatography eluting with methylene chloride and analysed by gaschromatography coupled with mass spectrometry (GC/MS). The recovery of analytes was in the range of 42-101% and agreed well with their boiling temperatures (R2=0.779). Precision of the method was found between 7.6 and 19%. Quantification and detection limits for individual PAHs ranged from 0.011 to 0.032 and from 0.006 to 0.022 microg/Kg milk (wet weight), respectively. Quantification limit for the total fat determination was 0.26 g/Kg milk (wet weight). This procedure, applied to milk samples of ten healthy, non-smoking, Italian primiparae, living in rural or low-traffic zones, allowed for the identification and quantitative determination of naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, benzo(b)fluoranthene and benzo(k)fluoranthene in the mean concentration range 0.114-6.95 microg/Kg milk (wet weight). The most volatile compounds, which were not investigated elsewhere, were found at much higher concentrations than those observed for the others. No relation was found between PAH and total fat concentrations.


Assuntos
Lipídeos/análise , Leite Humano/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Adulto , Cromatografia em Gel , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , População Rural
16.
J Environ Monit ; 7(12): 1305-12, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16307088

RESUMO

Concentrations of dissolved and particle-associated n-alkanes, phthalates and polycyclic aromatic hydrocarbons (PAHs) were measured in sea surface microlayer (SML) and sub-surface water (SSL) samples collected in the coastal area of Terra Nova Bay, Antarctica, during the Austral spring 1998/1999. SML concentrations of the selected organic compounds were higher than SSL values and the enrichment factors were greater in the particulate phase than in the dissolved phase. During the same campaign, "fresh" snow samples, collected at different altitudes (from sea level up to 2670 m) near the coast on Mt Melbourne, immediately after a snowy event, were analysed in order to provide more information on air/sea exchange processes. The same classes of organic compounds found in sea water were also present in "fresh" snow samples. The surfactant fluorescent organic matter (SFOM), adsorbed on the microdrop aerosol surface, could be considered the main constituent of the enrichment and the carrier at higher altitudes of organic compounds. In fact, hydrocarbons (n-alkanes and PAHs), which are not surfactants like phthalates, could interact with SFOM and follow the same fate.


Assuntos
Água do Mar/química , Neve/química , Poluentes Químicos da Água/análise , Aerossóis , Alcanos/análise , Regiões Antárticas , Monitoramento Ambiental , Oceanos e Mares , Ácidos Ftálicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Sódio/análise , Esqualeno/análise
17.
Ann Chim ; 94(12): 875-87, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15689024

RESUMO

Performances of a pilot-scale reed bed for the olive mill wastewater (OMW) treatment were investigated, by monitoring influent and effluent pH, total suspended solids (TSS), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), total phosphorus and polyphenols. In order to reduce the suspended matter concentration and to avoid clogging, OMW was pre-treated by adding lime putty, calcium hydroxide and hydraulic lime. The best results were obtained with 2 g/L of hydraulic lime. Pre-treated OMW was dosed in the reed bed at dilution ratios of 1/3 and 1/10 (v/v), pointing up that the latter only did not give rise to reed suffering and allowed to obtain good and durable removal efficiencies, above all for COD (74.1+/-17.6%) and polyphenols (83.4+/-17.8%). Recycling of the effluent was quite effective for the improvement of the wastewater quality, allowing a further removal of 26-70%, depending on the parameter taken into account. A post-dosage study, carried out by feeding the reed bed with the effluent of an activated sludge plant, pointed up a rapid decreasing of the outlet concentrations of the investigated parameters to values compatible with Italian regulations concerning wastewater discharge in surface water. Polyphenols were the exception, being their outlet concentration at the end of post-dosage study around 2 mg/L.


Assuntos
Olea , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Reatores Biológicos , Ecossistema , Flavonoides/metabolismo , Concentração de Íons de Hidrogênio , Resíduos Industriais , Itália , Nitrogênio/metabolismo , Oxigênio/metabolismo , Fenóis/metabolismo , Fósforo/metabolismo , Polifenóis , Esgotos/química , Esgotos/microbiologia , Temperatura , Fatores de Tempo , Movimentos da Água
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