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1.
Chem Pharm Bull (Tokyo) ; 66(12): 1174-1180, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30504632

RESUMEN

Polygala Root (the root of Polygala tenuifolia WILLDENOW; Japanese name "Onji"), a well-known crude drug, traditionally used as an expectorant and sedative, has been attracting increased interest in recent years owing to its newly found pharmacological effect related to neuroprotection. However, there is no specific method for identifying and estimating the quality of this crude drug in the Japanese Pharmacopoeia, 17th edition. Therefore, in order to develop a TLC-based simple and convenient identification method using characteristic chemical marker(s) for the drug and its extract products, UV-sensitive constituents of Polygala Root were first investigated. A total of 23 aromatic compounds were isolated and characterized. Two new compounds, namely, polygalaonjisides A (1) and B (2), were characterized as syringic acid 4-O-(2'-O-ß-D-apiosyl)-ß-D-glucoside and 2-O-(ß-D-glucosyl)-3'-O-benzoylsucrose, respectively. Based on these phytochemical results, a TLC method focusing on three marker spots with Rf value of approximately 0.4-0.5 due to tenuifolisides A and B and 3,6'-di-O-sinapoylsucrose was proposed as a simple and convenient test to identify Polygala Root or its single-extract products on the market. The data presented in this paper could be useful in stipulating a confirmation test to identify Polygala Root.


Asunto(s)
Hidrocarburos Aromáticos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas/química , Polygala/química , Rayos Ultravioleta , Biomarcadores/análisis , Cromatografía en Capa Delgada , Hidrocarburos Aromáticos/química , Estructura Molecular , Extractos Vegetales/química , Control de Calidad
2.
Bioengineered ; 8(5): 446-450, 2017 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-28095107

RESUMEN

Petroleum wastewater samples from oil refinery and oil exploration site were treated by hyper phenol-tolerant Bacillus cereus (AKG1 and AKG2) in laboratory-scale batch process to assess their bioremediation efficacy. Quality of the treated wastewater samples were analyzed in terms of removal of chemical oxygen demand (COD), total organic carbon (TOC) and ammonium nitrogen content, and improvement of biological oxygen demand (BOD). Adaptation of these bacteria to the toxic environment through structural changes in their cell membranes was also highlighted. Among different combinations, the co-culture of AKG1 and AKG2 showed the best performance in degrading the wastewater samples.


Asunto(s)
Bacillus/clasificación , Bacillus/fisiología , Reactores Biológicos/microbiología , Petróleo/microbiología , Aguas Residuales/microbiología , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/métodos , Bacillus/efectos de los fármacos , Técnicas de Cultivo Celular por Lotes/métodos , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno/métodos , Proliferación Celular/fisiología , Hidrocarburos Aromáticos/aislamiento & purificación , Hidrocarburos Aromáticos/metabolismo , Fenol/administración & dosificación , Proyectos Piloto , Especificidad de la Especie , Contaminantes Químicos del Agua/aislamiento & purificación
3.
Environ Technol ; 37(9): 1045-53, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26508265

RESUMEN

Anaerobic/anoxic biodegradation of hydrocarbons offers an attractive approach to the removal of these compounds from polluted environments such as aquifers, aquatic sediments, submerged soils and subsurface soils. The application of nitrate was investigated to accelerate the degradation of gasoline components such as mono-aromatic hydrocarbons and total petroleum hydrocarbons (TPH) in soil by indigenous microorganisms under anoxic condition. The addition of nitrate had little effect on the degradation of mono-aromatic hydrocarbons m- & p-xylene, o-xylene, sec-butylbenzene and 1,2,4-trimethylbenzene, but facilitated the degradation of TPH (C6-C12) and mono-aromatic hydrocarbons toluene and ethylbenzene markedly. Furthermore, the more nitrate added, the higher the percentage of toluene, ethylbenzene and TPH (C6-C12) degraded after 180 days of anoxic incubation. Microorganisms capable of degrading toluene, ethylbenzene and TPH (C6-C12) with nitrate as the electron acceptor under anaerobic/anoxic condition are composed predominantly of Alpha-, Beta-, Gamma- or Delta-proteobacteria. Beta- and Gamma-proteobacteria were the main components of indigenous microorganisms, and accounted for 83-100% of the total amount of indigenous microorganisms in soil used in this study. Furthermore, the total amount of indigenous microorganisms increased with nitrate added. The addition of nitrate stimulated the growth of indigenous microorganisms, and therefore facilitated the degradation of toluene, ethylbenzene and TPH (C6-C12).


Asunto(s)
Gasolina/análisis , Hidrocarburos Aromáticos/análisis , Nitratos/metabolismo , Proteobacteria/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/análisis , Suelo/química , Anaerobiosis , Derivados del Benceno/análisis , Derivados del Benceno/aislamiento & purificación , Derivados del Benceno/metabolismo , Biodegradación Ambiental , Hidrocarburos Aromáticos/aislamiento & purificación , Hidrocarburos Aromáticos/metabolismo , Petróleo/análisis , Petróleo/metabolismo , Contaminantes del Suelo/aislamiento & purificación , Contaminantes del Suelo/metabolismo , Tolueno/análisis , Tolueno/aislamiento & purificación , Tolueno/metabolismo
4.
J Cosmet Sci ; 67(2): 71-92, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-29394011

RESUMEN

Natural peloids from sulfurous thermal springs are largely used in cosmetic and pelotherapy for the treatment of different dermatological conditions, including skin aging, dermatitis, and other eczemas. The beneficial effects are correlated to mineralogical and other thermal properties, as well as to the presence of natural substances with specific antioxidant activity. Few data are available for the comparison between natural peloids and synthetic (i.e., artificially maturated) muds. In this context, the natural substances and antioxidant activity of natural white mud (WM) and dark mud (DM) peloids from the sulfurous thermal spring pool Bagnaccio (Viterbo, Italy) have been studied in detail to evaluate possible relationships between physicochemical properties and therapeutic effect. A large panel of natural substances in WM and DM were characterized for the first time by ³¹P-nuclear magnetic resonance and gas chromatography associated to mass spectrometry analysis. Polar fractions of WM and DM peloids were characterized by the presence of several bioactive natural compounds, showing high antioxidant activity and DNA protective effect, as evaluated by 2,2-diphenyl-1-picrylhydrazyl assay, and hydrogen peroxide­induced DNA breakage in the alkaline comet assay. The antioxidant activity and DNA protective effect could be attributed to radical scavenging rather than a modulatory effect on the induced DNA repair, and are of order of intensity higher than that reported for synthetic muds.


Asunto(s)
Alcaloides/farmacología , Depuradores de Radicales Libres/farmacología , Hidrocarburos Aromáticos/farmacología , Fenoles/farmacología , Terpenos/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Alcanos/química , Alcanos/aislamiento & purificación , Alcanos/farmacología , Alquenos/química , Alquenos/aislamiento & purificación , Alquenos/farmacología , Animales , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/química , Células CHO , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Cricetulus , ADN/efectos de los fármacos , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Manantiales de Aguas Termales , Humanos , Hidrocarburos Aromáticos/química , Hidrocarburos Aromáticos/aislamiento & purificación , Peróxido de Hidrógeno/antagonistas & inhibidores , Peróxido de Hidrógeno/química , Italia , Espectroscopía de Resonancia Magnética , Ratones , Peloterapia , Fenoles/química , Fenoles/aislamiento & purificación , Picratos/antagonistas & inhibidores , Picratos/química , Terpenos/química , Terpenos/aislamiento & purificación
5.
Phytochem Anal ; 26(5): 320-30, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25982347

RESUMEN

INTRODUCTION: There has been increasing interest dedicated to the phenolic compounds with a view to their antioxidant and healthy properties. Recent studies have focused on plants from the Lamiaceae family with special interest in phenolic compounds antioxidant potential. OBJECTIVE: The metabolite profile of methanolic extracts from two Lamiacea medicinal plants was investigated. MATERIALS AND METHODS: Mentha pulegium and Origanum majorana methanolic extracts were analysed using reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) coupled to electrospray ionisation quadrupole time-of-flight mass spectrometry (ESI-QTOF-MS) detection in the negative ion mode. RESULTS: A total of 85 metabolites were characterised from different families, such as organic acids and derivatives, amino acids and derivatives, nucleosides, phenolic compounds as well as other polar metabolites, by using the MS and MS/MS information provided by the QTOF-MS. However, the total phenols and flavonoids were also quantified spectrophotometrically and they registered higher amounts in Mentha pulegium than in Origanum majorana extract. Gallocatechin was the major compound in M. pulegium extract whereas quercetin dimethyl ether, jaceidin and dihydrokaempferide were the major ones in O. majorana extract. CONCLUSION: The distribution of phenolic compounds in the methanolic extract showed a variation among studied plants. Mentha pulegium can be considered as a source of gallocatechin.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Mentha pulegium/química , Origanum/química , Extractos Vegetales/análisis , Catequina/análogos & derivados , Catequina/análisis , Catequina/química , Catequina/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Cromatografía de Fase Inversa/métodos , Hidrocarburos Aromáticos/análisis , Hidrocarburos Aromáticos/química , Hidrocarburos Aromáticos/aislamiento & purificación , Mentha pulegium/metabolismo , Metanol/química , Origanum/metabolismo , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/química , Plantas Medicinales/metabolismo , Quercetina/análisis , Quercetina/química , Quercetina/aislamiento & purificación , Especificidad de la Especie , Espectrometría de Masa por Ionización de Electrospray/métodos , Triterpenos/análisis , Triterpenos/química , Triterpenos/aislamiento & purificación
6.
Biotechnol Adv ; 33(6 Pt 1): 745-55, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26008965

RESUMEN

Increasing soil pollution problems have caused world-wide concerns. Large numbers of contaminants such as polycyclic aromatic hydrocarbons (PAHs), petroleum and related products, pesticides, chlorophenols and heavy metals enter the soil, posing a huge threat to human health and natural ecosystem. Chemical and physical technologies for soil remediation are either incompetent or too costly. Composting or compost addition can simultaneously increase soil organic matter content and soil fertility besides bioremediation, and thus is believed to be one of the most cost-effective methods for soil remediation. This paper reviews the application of composting/compost for soil bioremediation, and further provides a critical view on the effects of this technology on microbial aspects in contaminated soils. This review also discusses the future research needs for contaminated soils.


Asunto(s)
Biodegradación Ambiental , Hidrocarburos Aromáticos/aislamiento & purificación , Metales Pesados/aislamiento & purificación , Plaguicidas/aislamiento & purificación , Petróleo/análisis , Contaminantes del Suelo/aislamiento & purificación , Bacterias/metabolismo , Biotecnología
7.
Environ Technol ; 36(13-16): 1785-94, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25624137

RESUMEN

Anaerobic digestion is investigated as a sustainable depurative strategy of olive oil mill wastewater (OOMW). The effect of thermal pretreatment on the anaerobic biodegradation of aromatic compounds present in (OMWW) was investigated. The anaerobic degradation of phenolic compounds, well known to be the main concern related to this kind of effluents, was monitored in batch anaerobic tests at a laboratory scale on samples pretreated at mild (80±1 °C), intermediate (90±1 °C) and high temperature (120±1 °C). The obtained results showed an increase of 34% in specific methane production (SMP) for OMWW treated at the lowest temperature and a decrease of 18% for treatment at the highest temperature. These results were related to the different decomposition pathways of the lignocellulosic compounds obtained in the tested conditions. The decomposition pathway was determined by measuring the concentrations of volatile organic acids, phenols, and chemical oxygen demand (COD) versus time. Cyclohexane carboxylic acid (CHCA) production was identified in all the tests with a maximum concentration of around 200 µmol L(-1) in accordance with the phenols degradation, suggesting that anaerobic digestion of aromatic compounds follows the benzoyl-CoA pathway. Accurate monitoring of this compound was proposed as the key element to control the process evolution. The total phenols (TP) and total COD removals were, with SMP, the highest (TP 62.7%-COD 63.2%) at 80 °C and lowest (TP 44.9%-COD 32.2%) at 120 °C. In all cases, thermal pretreatment was able to enhance the TP removal ability (up to 42% increase).


Asunto(s)
Bacterias Anaerobias/metabolismo , Calefacción/métodos , Hidrocarburos Aromáticos/aislamiento & purificación , Metano/metabolismo , Aceites de Plantas/metabolismo , Aguas Residuales/química , Agricultura/métodos , Biodegradación Ambiental , Ácidos Ciclohexanocarboxílicos/análisis , Ácidos Ciclohexanocarboxílicos/metabolismo , Retroalimentación , Retroalimentación Fisiológica/fisiología , Hidrocarburos Aromáticos/química , Residuos Industriales/prevención & control , Metano/química , Metano/aislamiento & purificación , Aceite de Oliva , Aceites de Plantas/química , Temperatura , Aguas Residuales/análisis , Contaminantes Químicos del Agua , Purificación del Agua/métodos
8.
Chemosphere ; 92(11): 1465-71, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23632245

RESUMEN

The molecular scale sorption, diffusion and distribution of asphaltene, resin, aromatic and saturate fractions of heavy crude oil on quartz surface were studied using molecular dynamic simulation. Sorption of saturates on quartz decreased by 31% when temperature increased from 298 to 398K while opposite trend was observed for resins, but insignificant changes were found in asphaltenes and aromatics. Despite of this variety, the main contribution of interactions was van der Waals energy (>90%) irrespective of molecular components and temperatures. The diffusion coefficient of saturates was predicted as 10.8×10(-10)m(2)s(-1) while that of the remaining fractions was about 4×10(-10)m(2)s(-1) at 298K. The most likely oil distribution on quartz surface was that aromatics and saturates transported randomly into and out of the complex consisting of asphaltenes surrounded by resins, which was influenced by temperature. Overall, the knowledge on quartz-oil and oil-oil interactions gained in this study is essential for future risk assessment and remediation activities as previous studies on soil remediation either limited to light oil fractions with <40 carbons or treated the heavy crude oil as a single pseudo entity ignoring the interactions between oil fractions.


Asunto(s)
Alcanos/química , Hidrocarburos Aromáticos/química , Simulación de Dinámica Molecular , Petróleo/análisis , Cuarzo , Absorción , Alcanos/aislamiento & purificación , Difusión , Hidrocarburos Aromáticos/aislamiento & purificación , Conformación Molecular , Solventes/química , Propiedades de Superficie
9.
Water Sci Technol ; 66(12): 2754-63, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23109595

RESUMEN

An integrated fluidized bed reactor (FBR) has been employed as the treatment for petrochemical industry wastewaters with high organic matter and aromatic compounds, under anaerobic and aerobic conditions. The system was operated at hydraulic residence time (HRT) of 2.7 and 2.2 h in the anaerobic and aerobic reactor, respectively. The degree of fluidization in the beds was 30%. This system showed a high performance on the removal of organic matter and aromatic compounds. At different organic loading rates (OLR), the chemical oxygen demand (COD) removal in the anaerobic reactor was close to 85% and removals of the COD up to 94% were obtained in the aerobic reactor. High removals of benzene, toluene, ethylbenzene, xylenes, styrene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene and naphthalene were achieved in this study.


Asunto(s)
Reactores Biológicos/microbiología , Hidrocarburos Aromáticos/aislamiento & purificación , Petróleo/análisis , Aguas Residuales/química , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Aerobiosis , Anaerobiosis , Bacterias/ultraestructura , Adhesión Bacteriana , Biodegradación Ambiental , Biopelículas/crecimiento & desarrollo , Análisis de la Demanda Biológica de Oxígeno , Metano/análisis , Oxígeno/análisis , Contaminantes Químicos del Agua/aislamiento & purificación
10.
J Chromatogr A ; 1218(21): 3217-23, 2011 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-21306718

RESUMEN

Thermochemical conversion processes play a crucial role in all routes from fossil and renewable resources to base chemicals, fuels and energy. Hence, a fundamental understanding of these chemical processes can help to resolve the upcoming challenges of our society. A bench scale pyrolysis set-up has been used to study the thermochemical conversion of rapeseed oil methyl ester (RME), i.e. a mixture of fatty acid methyl esters. A GC×GC, equipped with both a flame ionization detector (FID) and a time-of-flight mass spectrometer (TOF-MS), allows quantitative and qualitative characterization of the reactor feed and product. Analysis of the latter is accomplished using a dedicated high temperature on-line sampling system. Temperature programmed analysis, starting at -40°C, permits effluent characterization from methane up to lignoceric acid methyl ester (C(25)H(50)O(2)), in a single run of the GC×GC. The latter combines a 100% dimethylpolysiloxane primary column with a 50% phenyl polysilphenylene-siloxane secondary column. Modulation is started when the oven temperature reaches 40°C, thus dividing the chromatogram in a conventional 1D and a comprehensive 2D part. The proposed quantification approach allows to combine the quantitative GC×GC analysis with 2 other on-line 1D GC analyses, resulting in a complete and detailed product composition including the measurement of CO, CO(2), formaldehyde and water. The GC×GC reveals that the product stream contains a huge variety of valuable products, such as linear alpha olefins, unsaturated esters and aromatics, that could not have been identified and quantified accurately with conventional 1D GC because of peak overlap.


Asunto(s)
Ésteres/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Aromáticos/química , Aceites de Plantas/química , Algoritmos , Biocombustibles/análisis , Diseño de Equipo , Ácidos Grasos Monoinsaturados , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Calor , Hidrocarburos Aromáticos/aislamiento & purificación , Aceite de Brassica napus
11.
J Environ Monit ; 13(3): 605-13, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21243149

RESUMEN

Ground and surface water contamination resulting from the leakage of crude oil and refined petroleum products is a serious and growing environmental problem throughout the world. Consequently, a study of the use of electrochemical treatment in the clean-up was undertaken with the aim of reducing the water contamination by aromatic pollutants to more acceptable levels. In the experiments described, water contamination by refined petroleum products was simulated under laboratory conditions. Electrochemical treatment, using aluminium electrodes, has been optimised by full factorial design and surface response analysis in term of BTEX and PAHs removal and energy consumption. The optimal conditions of pH, current density, electrolysis time, electrolyte type, and electrolyte concentration have then been applied in the treatment of real water samples which were monitored as petroleum contaminated samples. Treatment results have shown that electrochemical methods could achieve the concentration of these pollutants to undetectable levels in particular groundwater and surface water, hence, they can be highly effective in the remediation of water contaminated by aromatic hydrocarbons, and the use of these processes is therefore recommended.


Asunto(s)
Hidrocarburos Aromáticos/aislamiento & purificación , Petróleo , Contaminantes Químicos del Agua/aislamiento & purificación , Electrólisis , Concentración de Iones de Hidrógeno , Compuestos de Sodio
12.
J Chromatogr A ; 1218(21): 3208-16, 2011 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-20934179

RESUMEN

Comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS) was used for the characterization of aromatic compounds present in extra heavy gas oil (EHGO) from Brazil. Individual identification of EHGO compounds was successfully achieved in addition to group-type separation on the chromatographic plane. Many aromatic hydrocarbons, especially polycyclic aromatic hydrocarbons and sulfur compounds, were detected and identified, such as chrysenes, phenanthrenes, perylenes, benzonaphthothiophenes and alkylbenzonaphthothiophenes. In addition, triaromatic steroids, methyl-triaromatic steroids, tetrahydrochrysenes and tetraromatic pentacyclic compounds were present in the EHGO aromatic fractions. Considering the roof-tile effect observed for many of these compound classes and the high number of individual compounds identified, GC×GC-TOFMS is an excellent technique to characterize the molecular composition of the aromatic fraction from EHGO samples. Moreover, data processing allowed the quantification of aromatic compounds, in class and individually, using external standards. EHGO data were obtained in µgg(-1), e.g., benzo[a]pyrene were in the range 351 to 1164µgg(-1). Thus, GC×GC-TOFMS was successfully applied in EHGO quantitative analysis.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Aromáticos/química , Petróleo/análisis , Gasolina , Hidrocarburos Aromáticos/análisis , Hidrocarburos Aromáticos/aislamiento & purificación , Procesamiento de Señales Asistido por Computador
13.
Bioresour Technol ; 102(2): 543-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20801021

RESUMEN

Water is the most common choice of absorption medium selected in many gasification systems. Because of poor solubility of tar in water, hydrophobic absorbents (diesel fuel, biodiesel fuel, vegetable oil, and engine oil) were studied on their absorption efficiency of biomass tar and compared with water. The results showed that only 31.8% of gravimetric tar was removed by the water scrubber, whereas the highest removal of gravimetric tar was obtained by a vegetable oil scrubber with a removal efficiency of 60.4%. When focusing on light PAH tar removal, the absorption efficiency can be ranked in the following order; diesel fuel>vegetable oil>biodiesel fuel>engine oil>water. On the other hand, an increase in gravimetric tar was observed for diesel fuel and biodiesel fuel scrubbers because of their easy evaporation. Therefore, the vegetable oil is recommended as the best absorbent to be used in gasification systems.


Asunto(s)
Biomasa , Aceites/química , Breas/aislamiento & purificación , Agua/química , Absorción , Gasolina/análisis , Hidrocarburos Aromáticos/aislamiento & purificación , Naftalenos/aislamiento & purificación , Aceites de Plantas/química , Madera/química
14.
Water Res ; 45(1): 93-104, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20804998

RESUMEN

We studied the occurrence, removal, and fate of 16 polycyclic aromatic hydrocarbons (PAHs) and 23 volatile organic compounds (VOCs) in Italian municipal wastewater treatment systems in terms of their common contents and forms, and their apparent and actual removal in both conventional activated-sludge processes (CASP) and membrane bioreactors (MBRs). We studied five representative full-scale CASP treatment plants (design capacities of 12,000 to 700,000 population-equivalent), three of which included MBR systems (one full-scale and two pilot-scale) operating in parallel with the conventional systems. We studied the solid-liquid partitioning and fates of these substances using both conventional samples and a novel membrane-equipped automatic sampler. Among the VOCs, toluene, ethylbenzene, xylenes, styrene, 1,2,4-trimethylbenzene, and 4-chlorotoluene were ubiquitous, whereas naphthalene, acenaphthene, fluorene, and phenanthrene were the most common PAHs. Both PAHs and aromatic VOCs had removal efficiencies of 40-60% in the headworks, even in plants without primary sedimentation. Mainly due to volatilization, aromatic VOCs had comparable removal efficiencies in CASP and MBRs, even for different sludge ages. MBRs did not enhance the retention of PAHs sorbed to suspended particulates compared with CASPs. On the other hand, the specific daily accumulation of PAHs in the MBR's activated sludge decreased logarithmically with increasing sludge age, indicating enhanced biodegradation of PAHs. The PAH and aromatic VOC contents in the final effluent are not a major driver for widespread municipal adoption of MBRs, but MBRs may enhance the biodegradation of PAHs and their removal from the environment.


Asunto(s)
Reactores Biológicos/microbiología , Hidrocarburos Aromáticos/aislamiento & purificación , Membranas Artificiales , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/aislamiento & purificación
15.
Anal Chem ; 80(18): 7090-6, 2008 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-18700781

RESUMEN

A sequential ultrasonic extraction method for contaminated soils with weathered hydrocarbons is presented. The method covers the determination of total petroleum hydrocarbons between nC 8 and nC 40, and subranges of hydrocarbons including diesel range organic compounds, kerosene range organic compounds, and mineral oil range organic compounds in soils. Further modifications to the carbon banding may be made as requested for risk assessment. These include a series of ranges known as Texas banding (from the Texas Risk Reduction Program) as well as separation of the aliphatic and aromatic fractions. The method can be routinely used for measuring hydrocarbons down to 10 mg kg (-1) in soil. Lower limits can be achieved by employing a suitable solvent concentration step following extraction; however, this would result in increased cycle time. Detection limits may vary for individual carbon ranges calculated on the percentage of the full range they cover. With an extraction efficiency and recovery between >or=95 and 99%, this method can be easily positioned as a good alternative to Soxhlet extraction and shows a good potential for implementation as a standard method potentially providing further insight to the contaminated land sector.


Asunto(s)
Fraccionamiento Químico/métodos , Hidrocarburos/análisis , Hidrocarburos/aislamiento & purificación , Contaminantes del Suelo/análisis , Contaminantes del Suelo/aislamiento & purificación , Hidrocarburos Aromáticos/análisis , Hidrocarburos Aromáticos/aislamiento & purificación , Petróleo/análisis , Riesgo , Sensibilidad y Especificidad , Solventes/química , Ultrasonido , Reino Unido
16.
Planta Med ; 74(10): 1246-52, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18612943

RESUMEN

In liver injury, hepatic stellate cells (HSCs) acquire an activated phenotype, migrate to the injured region in response to chemotactic factors and produce extracellular matrix (ECM) proteins including alpha-smooth muscle actin (alpha-SMA) and collagen in order to repair the damage. HSC-T6, a cell line of rat HSCs, was used in in vitro experiments. TGF-beta1 was used as a chemoattractant. The expression of alpha-SMA was used as a marker of activated hepatic stellate cells and cell migration was assayed with the Transwell method to investigate the active principles of the roots of Rheum palmatum L. (Dahuang), a well-known traditional Chinese herb used for treating liver diseases. Under cell activation and chemotaxis-directed fractionation and purification, four anthraquinones, rhein ( 1), emodin ( 2), chrysophanol ( 3) and physcion ( 4), and four phenylbutanoids, lindleyin ( 5), isolindleyin ( 7), 4-(4'-hydroxyphenyl)-2-butanone 4'- O-beta- D-glucopyranoside ( 8), and 4-(4'-hydroxyphenyl)-2-butanone ( 9), and a stilbene, 3,5,4'-trihydroxystilbene 4'- O-beta- D-glucopyranoside 6'- O-gallate ( 6) were isolated from the active fractions. Among them, compounds 1 and 2 inhibited alpha-SMA expression. However, compounds 3, 4, 6 and 8 attenuated chemotactic migration, but not alpha-SMA expression.


Asunto(s)
Actinas/metabolismo , Quimiotaxis/efectos de los fármacos , Hidrocarburos Aromáticos/farmacología , Rheum/química , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Línea Celular , Medicamentos Herbarios Chinos/uso terapéutico , Matriz Extracelular/metabolismo , Hidrocarburos Aromáticos/aislamiento & purificación , Hidrocarburos Aromáticos/uso terapéutico , Hígado/citología , Cirrosis Hepática/tratamiento farmacológico , Fenoles/aislamiento & purificación , Fenoles/farmacología , Fenoles/uso terapéutico , Fitoterapia , Raíces de Plantas/química , Ratas , Ratas Sprague-Dawley
17.
Zhongguo Zhong Yao Za Zhi ; 32(16): 1669-75, 2007 Aug.
Artículo en Chino | MEDLINE | ID: mdl-18027665

RESUMEN

OBJECTIVE: To analyze the chemical components of the essential oil extracted from the seeds of Myristica fragrans (nutmeg) processed by different methods (steamed with water steam, roasted with flour, sauted with flour, roasted with talcum powder, roasted with loess, and roasted with bran) and to provide quality control foundations in the sciences. METHOD: The essential oil was extracted by steam distillation and separated with GC capillary column. The relative content of every compound was determined with area normalization method and the structures were elucidated by GC-MS technique. RESULT: Fifty-eight to one hundred and four of chromatographic peaks were detected, among them seventy-six compounds accounting for 98.32% to 99.99% of the total essential oil in nutmeg were identified, which were composed of 69.15% to 97.24% for monoterpenoids and 2.06% to 25.51% for aromatic compounds of the total essential oil, respectively. CONCLUSION: It was shown that monoterpenoids and their derivatives were main composition, and aromatic compounds were secondary composition in the total essential oil of nutmeg grows in Indonesia and processed by different traditional methods on the basis of theory of traditional Chinese medicine. In addition, it was suggested that we should be careful to use processed nutmeg owing to contain safrole and a-asarone induced genetoxicity in animals and mutagenicity in the Ames Salmonella assay, and myristicin and elemicin induced narcotism in human. The processed method roasted with bran for nutmeg may be better and will be developed.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Myristica/química , Aceites Volátiles/aislamiento & purificación , Plantas Medicinales/química , Tecnología Farmacéutica/métodos , Derivados de Alilbenceno , Anisoles/química , Anisoles/aislamiento & purificación , Compuestos de Bencilo/química , Compuestos de Bencilo/aislamiento & purificación , Dioxolanos/química , Dioxolanos/aislamiento & purificación , Hidrocarburos Aromáticos/química , Hidrocarburos Aromáticos/aislamiento & purificación , Estructura Molecular , Monoterpenos/química , Monoterpenos/aislamiento & purificación , Aceites Volátiles/química , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Pirogalol/análogos & derivados , Pirogalol/química , Pirogalol/aislamiento & purificación , Reproducibilidad de los Resultados , Safrol/química , Safrol/aislamiento & purificación , Semillas/química
18.
J Chromatogr A ; 1171(1-2): 1-7, 2007 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-17919647

RESUMEN

BTEX-S compounds are widely distributed in the environment and can be present in different foodstuffs, including olive oil. Taking into account the risks of the exposure to these compounds, analytical methods for their determination in different matrices are mandatory. In this paper, the use of surfactant-coated multiwalled carbon nanotubes as additive in liquid-liquid extraction is applied for the determination of single-ring aromatic compounds in olive oil samples. After sample treatment, the aqueous extracts are subsequently analyzed by headspace/gas chromatography/mass spectrometry allowing the determination of BTEX-S within ca. 15 min. Each stage of the proposed LLE/HS/GC/MS configuration involves a selectivity enhancement avoiding the interference of other compounds of the sample matrix. Limits of detection were in the range 0.25 ng mL(-1) (obtained for ethylbenzene) and 0.43 ng mL(-1) (for benzene). The repeatability of the proposed method expressed as RSD varied between 1.9% (styrene) and 3.3% (benzene) (n=11).


Asunto(s)
Fraccionamiento Químico/instrumentación , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Hidrocarburos Aromáticos/aislamiento & purificación , Nanotubos de Carbono/química , Aceites de Plantas/química , Tensoactivos/química , Benceno/aislamiento & purificación , Derivados del Benceno/aislamiento & purificación , Fraccionamiento Químico/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Aromáticos/clasificación , Aceite de Oliva , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estireno/aislamiento & purificación , Tolueno/aislamiento & purificación , Xilenos/aislamiento & purificación
19.
Ultrason Sonochem ; 13(1): 54-60, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16223688

RESUMEN

A comparative study of traditional simultaneous distillation extraction (SDE), microwave assisted hydrodistillation extraction (MWHD) and ultrasound-assisted extraction (USE) is presented, for the extraction of essential oils from fresh garlic (Allium sativum) cloves. Each method is evaluated in terms of qualitative and quantitative composition of the isolated essential oil. The highly reactive sulfur molecules of the garlic volatile fraction show variable response to the different isolation methods. The application of ultrasound for the extraction of the essential oil is considered to cause a lesser damage of thermal-sensitive molecules, thus, providing a better approach of the compounds primarily responsible for the characteristic odor and taste of freshly chopped garlic. All heat-involving isolation procedures have been shown to differentiate the volatile-fraction profile as analyzed by GC-MS. Especially when grouping the compounds into cyclic and acyclic, the percentage concentrations drop from 77.4% to 8.7% for the acyclic while that of the cyclic compounds increase from 4.7% to 70.8%. The observed fact may be attributed to the effect of the heat applied, which changes from harsh thermal treatment (SDE) to short time thermal (MWHD) and room-temperature isolation (USE). The use of USE proves to be crucial in order to provide reliable insight into garlic's chemistry.


Asunto(s)
Fraccionamiento Químico/métodos , Ajo/química , Hidrocarburos Aromáticos/química , Hidrocarburos Aromáticos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Sonicación , Ajo/efectos de la radiación , Hidrocarburos Aromáticos/efectos de la radiación , Extractos Vegetales/química , Extractos Vegetales/efectos de la radiación
20.
Environ Sci Technol ; 39(17): 6649-63, 2005 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16190224

RESUMEN

The potential occurrence of endocrine-disrupting compounds (EDCs) as well as pharmaceuticals and personal care products (PPCPs) in drinking water supplies raises concern over the removal of these compounds by common drinking water treatment processes. Three drinking water supplies were spiked with 10 to 250 ng/L of 62 different EDC/ PPCPs; one model water containing an NOM isolate was spiked with 49 different EDC/PPCPs. Compounds were detected by LC/MS/MS or GC/MS/MS. These test waters were subjected to bench-scale experimentation to simulate individual treatment processes in a water treatment plant (WTP). Aluminum sulfate and ferric chloride coagulants or chemical lime softening removed some polyaromatic hydrocarbons (PAHs) but removed <25% of most other EDC/ PPCPs. Addition of 5 mg/L of powder activated carbon (PAC) with a 4-h contact time removed 50% to >98% of GC/ MS/MS compounds (more volatile) and 10% to >95% of LC/ MS/MS compounds (more polar); higher PAC dosages improved EDC/PPCP removal. EDC/PPCP percentage removal was independent of the initial compound concentration. Octanol-water partition coefficients served as a reasonable indicator of compound removal under controlled PAC test conditions, except for EDC/PPCPs that were protonated or deprotonated at the test pH and some that contained heterocyclic or aromatic nitrogen. Separate chlorine or ozone experiments decreased the EDC/PPCP initial concentration by <10% to >90%; EDC/PPCPs were likely transformed to oxidation byproducts. Ozone oxidized steroids containing phenolic moieties (estradiol, ethynylestradiol, or estrone) more efficiently than those without aromatic or phenolic moieties (androstenedione, progesterone, and testosterone). EDC/PPCP reactivity with oxidants were separated into three general groups: (1) compounds easily oxidized (>80% reacted) by chlorine are always oxidized at least as efficiently by ozone; (2) 6 of the -60 compounds (TCEP, BHC, chlordane, dieldrin, heptachlor epoxide, musk ketone) were poorly oxidized (<20% reacted) by chlorine or ozone; (3) compounds (24 of 60) reacting preferentially (higher removals) with ozone rather than chlorine. Conventional treatment (coagulation plus chlorination) would have low removal of many EDC/PPCPs, while addition of PAC and/or ozone could substantially improve their removals. Existing strategies that predict relative removals of herbicides, pesticides, and other organic pollutants by activated carbon or oxidation can be directly applied for the removal of many EDC/PPCPs, but these strategies need to be modified to account for charged (protonated bases or deprotonated acids) and aliphatic species. Some compounds (e.g., DEET, ibuprofen, gemfibrozil) had low removals unless ozonation was used. Other compounds had low removals by all the WTP processes considered (atrazine, iopromide, meprobamate, TCEP), and removal processes capable of removing these types of compounds should be investigated.


Asunto(s)
Disruptores Endocrinos/aislamiento & purificación , Preparaciones Farmacéuticas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua , Abastecimiento de Agua , Compuestos de Alumbre/farmacología , Compuestos de Calcio/farmacología , Carbón Orgánico/farmacología , Cloruros , Coagulantes/farmacología , Monitoreo del Ambiente , Compuestos Férricos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Compuestos Heterocíclicos/aislamiento & purificación , Hidrocarburos Aromáticos/aislamiento & purificación , Concentración de Iones de Hidrógeno , Nitrógeno/química , Nitrógeno/aislamiento & purificación , Óxidos/farmacología , Ozono/química , Fenoles/aislamiento & purificación
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