Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Food Chem Toxicol ; 134 Suppl 2: 110948, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31756354

RESUMEN

The existing information supports the use of this material as described in this safety assessment. 4-(p-Hydroxyphenyl)-2-butanone was evaluated for genotoxicity, repeated dose toxicity, developmental and reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data show that 4-(p-hydroxyphenyl)-2-butanone is not genotoxic. Data on 4-(p-hydroxyphenyl)-2-butanone provide a calculated MOE >100 for the repeated dose toxicity endpoint. The developmental and reproductive toxicity and local respiratory toxicity endpoints were evaluated using the TTC for a Cramer Class I material, and the exposure to 4-(p-hydroxyphenyl)-2-butanone is below the TTC (0.03 mg/kg/day and 1.4 mg/day, respectively). Data from 4-(p-hydroxyphenyl)-2-butanone show that there are no safety concerns for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on UV spectra; 4-(p-hydroxyphenyl)-2-butanone is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; 4-(p-hydroxyphenyl)-2-butanone was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.


Asunto(s)
Butanonas/toxicidad , Odorantes , Animales , Butanonas/química , Seguridad de Productos para el Consumidor , Evaluación Preclínica de Medicamentos , Determinación de Punto Final , Humanos , Pruebas de Mutagenicidad , Nivel sin Efectos Adversos Observados , Medición de Riesgo , Salmonella typhimurium/efectos de los fármacos
2.
Comput Biol Chem ; 75: 178-195, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29883916

RESUMEN

The present paper deals with in silico evaluation of 32 virtually designed transition metal complexes of 2-butanone thiosemicarbazone and N,S,O containing donor hetero-ligands namely py, bpy, furan, thiophene, 2-picoline, 1,10-phenanthroline, piperazine and liquid ammonia. The complexes were designed with a view to assess their potential anticancer, antioxidant and antibacterial activity. The absorption, distribution, metabolism, excretion and toxicity (ADMET) properties of the chosen ligands were calculated by admetSAR software. Metabolic sites of different ligands likely to undergo metabolism were predicted using Metaprint 2D. The proposed complexes were also evaluated for their drug-like quality based on Lipinski's, Veber, Ghose and leadlikeness filters. Druglikeness and toxicity potential were predicted by OSIRIS property explorer. The pharmacokinetic properties and bioactivity scores were calculated by Molinspiration tool. Bioactivity scores of the complexes were predicted for drug targets including enzymes, nuclear receptors, kinase inhibitors, G-protein coupled receptor ligands and ion channel modulators. Molecular docking of selected Fe(II) mixed-ligand complexes was performed using AutoDock version 4.2.6 and i-GEMDOCK version 2.1 with two target proteins namely Ribonucleotide reductase (RR) and Topoisomerase II (Topo II). The results were compared with three standard reference drugs viz. Doxorubicin HCl, Letrozole (anticancer) and Tetracycline (antibiotic). Multivariate data obtained were analyzed using principal component analysis (PCA) for visualization and projection as scatter and 3D plots. Positive results obtained for hetero-ligands using admetSAR version 1.0 indicated good absorption and transport kinetics of the hetero-ligand complexes through the human intestine and blood-brain barrier. The hetero-ligands were predicted to have no associated mutagenic effect(s) also. However, none of the hetero-ligands was predicted to be Caco-2 (human colon cancer cell line) permeable. Most of the hetero-ligands and the parent ligand (2-butanone thiosemicarbazone) were predicted to undergo Phase-I metabolism prior to excretion using MetaPrint2D software. Pharmacokinetic evaluation of the proposed complexes revealed that all complexes displayed drug-like character and were predicted to have no apparent toxic side-effects. All the proposed complexes showed moderate to good biological activity scores (-5.0 to 0.0). Mixed complexes with bpy, 2-picoline and 1,10-phenanthroline showed significant bioactivity scores (as enzyme inhibitors) in the range 0.02-0.13. Likewise, good docking scores were obtained for Fe (II) complexes with the same ligands. [FeL(2-pic)2] displayed the lowest binding energy (-6.47 kcal/mol) with respect to Topo II followed by [FeL(py)2] (-6.14 kcal/mol) as calculated by AutoDock version 4.2.6. With respect to binding with RR, [FeL(2--pic)2] again displayed the lowest binding energy (-7.21 kcal/mol) followed by [FeL(py)2] (-5.96 kcal/mol). On the basis of docking predictions and various other computational evaluations, four mixed-ligand complexes of Fe in +2 oxidation state with py, bpy, 2--picoline and 1,10-phenanthroline were synthesized with 2-butanone thiosemicarbazone. All the synthesized Fe complexes were characterized using various spectroscopic techniques and tested for their potential anticancer activity in vitro against human breast carcinoma cell line MDA-MB 231 and human lung carcinoma cell line A549 cell line using MTT assay. [FeL(2-pic)2], [FeL(bpy)], and [FeL(py)2] were found to exhibit significant antiproliferative activity with IC50 values in the range of 80-100 µM against breast and lung cancer cells. The synthesized Fe complexes also displayed mild antioxidant activities. The synthesized and studied Fe complexes have the potential for development into future anticancer agents if analyzed and modified further for improvement of their ADMET, solubility and permeability criteria set for potential drug-candidates.


Asunto(s)
Antineoplásicos/farmacología , Técnicas Químicas Combinatorias , Diseño Asistido por Computadora , Diseño de Fármacos , Compuestos Organometálicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Butanonas/química , Butanonas/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ligandos , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/química , Solubilidad , Relación Estructura-Actividad , Tiosemicarbazonas/química , Tiosemicarbazonas/farmacología , Elementos de Transición/química , Elementos de Transición/farmacología
3.
Int Immunopharmacol ; 50: 77-86, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28644965

RESUMEN

3, 4-Dihydroxybenzalacetone (DBL) is a constituent of Phellinus linteus. This study demonstrated the protective effect of DBL on lipopolysaccharide (LPS)-induced acute lung injuries in mice. Pretreatment with DBL significantly improved LPS-induced histological alterations in lung tissues. In addition, DBL markedly reduced the total cell number, the leukocytes, the protein concentrations, and decreased the release of nitrite, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 and the activities of matrix metalloproteinase (MMP)-2 and -9 in the bronchoalveolar lavage fluid. DBL also inhibited the W/D ratio and myeloperoxidase activity in the lung tissues. Western blot analysis indicated DBL efficiently blocked the protein expressions of inducible nitric oxide synthase, cyclooxygenase-2, MMP-2, MMP-9, and the phosphorylation of mitogen-activated protein kinase (MAPK), phosphoinositide-3-kinase (PI3K), AKT, Toll-like receptor 4 (TLR4) and nuclear factor (NF)-κB. Moreover, DBL enhanced the expression of anti-oxidant proteins, such as superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx). Based on our results, DBL might be a potential target for attenuating tissue oxidative injuries and nonspecific pulmonary inflammation.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Butanonas/uso terapéutico , Pulmón/efectos de los fármacos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Extractos Vegetales/uso terapéutico , Neumonía/tratamiento farmacológico , Lesión Pulmonar Aguda/inmunología , Animales , Butanonas/química , Citocinas/metabolismo , Regulación hacia Abajo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/inmunología , Pulmón/inmunología , Pulmón/patología , Masculino , Ratones , Ratones Endogámicos ICR , Óxido Nítrico/metabolismo , Phellinus , Fosfatidilinositol 3-Quinasas/metabolismo , Extractos Vegetales/química , Neumonía/inmunología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
4.
Phytother Res ; 31(1): 75-80, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27714886

RESUMEN

The aim of the study was to investigate the herb-drug interaction of Andrographis paniculata Nees (Acanthaceae) and Andrographolide (AN) with nabumetone (NAB) in wistar rats. Pharmacokinetic and pharmacodynamic interactions were studied after co-administration of APE and AN with NAB in Wistar rats. In pharmacokinetic studies, significant decrease in Cmax, AUC0-t and AUC0-∞ of 6-MNA after co-administration with pure AN and APE has been observed. Tmax of 6-MNA has been increased to 2 h from 1.5 h in AN + NAB treated group. Changes in mean residential time, clearance and volume of distribution of 6-MNA in APE + NAB treated group and AN + NAB treated group indicated interference of other components of APE other than AN. In pharmacodynamic study, significant decrease in antiarthritic activity of NAB on concomitant administration with APE and AN has been observed. The study concludes that NAB exhibits pharmacokinetic and pharmacodynamic interactions with APE and AN in rats thus alarms the concomitant use of herbal preparations containing APE and AN with NAB. Further study is needed to understand the mechanism and predict the herb-drug interaction in humans. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Andrographis/química , Butanonas/química , Diterpenos/química , Diterpenos/farmacocinética , Extractos Vegetales/química , Animales , Butanonas/farmacología , Femenino , Interacciones de Hierba-Droga , Nabumetona , Extractos Vegetales/farmacología , Ratas , Ratas Wistar
5.
Food Chem ; 201: 52-8, 2016 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-26868547

RESUMEN

Irradiation of food products and ingredients must be indicated by proper labeling. This study evaluated the appropriateness of the European Standard EN 1785:2003 for the detection of 2-alkylcyclobutanones, which are radiolysis products of fatty acids, in cashew nuts and nutmeg and confirmed its suitability to detect irradiation of cashew nut samples at average absorbed doses of 1 kGy and above. An alternative method was developed, which is based on matrix solid phase dispersion and subsequent separation and detection of oxime derivatives of 2-alkylcyclobutanones by high performance-high resolution mass spectrometry. It is more rapid, less resource consuming, and more sensitive than EN 1785:2003. This method allowed detection of 2-alkylcyclobutanones in cashew nuts irradiated at 100 Gray and in nutmeg irradiated at 400 Gray. None of the 26 cashew nut and 14 nutmeg samples purchased in different EU Member States contained traces of 2-alkylcyclobutanones.


Asunto(s)
Anacardium/química , Anacardium/efectos de la radiación , Butanonas/química , Técnicas de Química Analítica/métodos , Ciclobutanos/análisis , Myristica/química , Myristica/efectos de la radiación , Ácidos Grasos/química , Irradiación de Alimentos , Nueces/química , Nueces/efectos de la radiación
6.
Waste Manag ; 34(11): 2400-6, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25168185

RESUMEN

Mechanical-biological treatments (MBTs) of urban waste are growing in popularity in many European countries. Recent studies pointed out that their contribution in terms of volatile organic compounds (VOCs) and other air pollutants is not negligible. Compared to classical removal technologies, non-thermal plasmas (NTP) showed better performances and low energy consumption when applied to treat lowly concentrated streams. Therefore, to study the feasibility of the application of NTP to MBTs, a Dielectric Barrier Discharge reactor was applied to treat a mixture of air and methyl ethyl ketone (MEK), to simulate emissions from MBTs. The removal efficiency of MEK was linearly dependent upon time, power and specific input energy. Only 2-4% of MEK was converted to carbon dioxide (CO2), the remaining carbon being involved in the formation of byproducts (methyl nitrate and 2,3-butanedione, especially). For future development of pilot-scale reactors, acting on residence time, power, convective flow and catalysts will help finding a compromise between energy consumption, desired abatement and selectivity to CO2.


Asunto(s)
Contaminantes Atmosféricos/química , Contaminación del Aire/prevención & control , Butanonas/química , Compuestos Orgánicos Volátiles/química , Instalaciones de Eliminación de Residuos , Catálisis , Gases em Plasma/química
7.
Biochemistry ; 52(12): 2128-38, 2013 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-23484909

RESUMEN

Inhibitors of bacterial DD-peptidases represent potential antibiotics. In the search for alternatives to ß-lactams, we have investigated a series of compounds designed to generate transition state analogue structures upon reaction with DD-peptidases. The compounds contain a combination of a peptidoglycan-mimetic specificity handle and a warhead capable of delivering a tetrahedral anion to the enzyme active site. The latter includes a boronic acid, two alcohols, an aldehyde, and a trifluoroketone. The compounds were tested against two low-molecular mass class C DD-peptidases. As expected from previous observations, the boronic acid was a potent inhibitor, but rather unexpectedly from precedent, the trifluoroketone [D-α-aminopimelyl(1,1,1-trifluoro-3-amino)butan-2-one] was also very effective. Taking into account competing hydration, we found the trifluoroketone was the strongest inhibitor of the Actinomadura R39 DD-peptidase, with a subnanomolar (free ketone) inhibition constant. A crystal structure of the complex between the trifluoroketone and the R39 enzyme showed that a tetrahedral adduct had indeed formed with the active site serine nucleophile. The trifluoroketone moiety, therefore, should be considered along with boronic acids and phosphonates as a warhead that can be incorporated into new and effective DD-peptidase inhibitors and therefore, perhaps, antibiotics.


Asunto(s)
Actinomycetales/enzimología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/química , D-Ala-D-Ala Carboxipeptidasa de Tipo Serina/antagonistas & inhibidores , D-Ala-D-Ala Carboxipeptidasa de Tipo Serina/química , Antibacterianos/química , Antibacterianos/farmacología , Butanonas/química , Butanonas/farmacología , Dominio Catalítico , Cristalografía por Rayos X , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Modelos Moleculares , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , beta-Lactamas/farmacología
8.
J Mech Behav Biomed Mater ; 12: 144-50, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22732480

RESUMEN

This study describes the synthesis of Al(2)O(3)/SiC/ZrO(2) functionally graded material (FGM) in bio-implants (artificial joints) by electrophoretic deposition (EPD). A suitable suspension that was based on 2-butanone was applied for the EPD of Al(2)O(3)/SiC/ZrO(2), and a pressureless sintering process was applied as a presintering. Hot isostatic pressing (HIP) was used to densify the deposit, with beneficial mechanical properties after 2 h at 1800 °C in Ar atmosphere. The maximum hardness in the outer layer (90 vol.% Al(2)O(3)+10 vol.% SiC) and maximum fracture toughness in the core layer (75 vol.% Al(2)O(3)+10 vol.% SiC + 15 vol.% ZrO(2)) composite were 20.8±0.3 GPa and 8±0.1 MPa m(1/2), respectively. The results, when compared with results from Al(2)O(3)/ZrO(2) FGM, showed that SiC increased the compressive stresses in the outer layers, while the inner layers were under a residual tensile stress.


Asunto(s)
Óxido de Aluminio/química , Materiales Biocompatibles/química , Compuestos Inorgánicos de Carbono/química , Electroforesis/métodos , Prótesis Articulares , Compuestos de Silicona/química , Circonio/química , Butanonas/química , Fuerza Compresiva , Dureza , Calor , Ensayo de Materiales , Polvos , Diseño de Prótesis , Estrés Mecánico , Propiedades de Superficie , Temperatura , Resistencia a la Tracción , Difracción de Rayos X
9.
Eur J Med Chem ; 45(12): 5998-6004, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20980079

RESUMEN

Our continuing effort of searching bioactive substances from the Formosan soft coral Cladiella australis has led to the isolation of a bioactive substance austrasulfone (1), which possesses significant neuroprotective activities. A straightforward synthesis of 1 was achieved by a two-step reaction sequence. Dihydroaustrasulfone alcohol (3), the synthetic precursor of 1, not only exhibited in vitro anti-inflammatory activity, but also showed potent therapeutic ability in the treatment of neuropathic pain, atherosclerosis, and multiple sclerosis in rats.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Aterosclerosis/tratamiento farmacológico , Butanonas/farmacología , Esclerosis Múltiple/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Dolor/tratamiento farmacológico , Sulfonas/farmacología , Animales , Antozoos , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Butanonas/síntesis química , Butanonas/química , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Masculino , Ratones , Estructura Molecular , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/química , Dimensión del Dolor , Ratas , Ratas Endogámicas Lew , Ratas Wistar , Sulfonas/síntesis química , Sulfonas/química
10.
Planta Med ; 76(15): 1654-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20425690

RESUMEN

Raspberry ketone (RK) is a natural phenolic compound of the red raspberry. The dietary administration of RK to male mice has been reported to prevent high-fat diet-induced elevation in body weight and to increase lipolysis in white adipocytes. To elucidate a possible mechanism for the antiobesity action of RK, its effects on the expression and the secretion of adiponectin, lipolysis, and fatty acid oxidation in 3T3-L1 were investigated. Treatment with 10 µM of RK increased lipolysis significantly in differentiated 3T3-L1 cells. An immunoassay showed that RK increased both the expression and the secretion of adiponectin, an adipocytokine mainly expressed and secreted by adipose tissue. In addition, treatment with 10 µM of RK increased the fatty acid oxidation and suppressed lipid accumulation in 3T3-L1 adipocytes. These findings suggest that RK holds great promise as an herbal medicine since its biological activities alter the lipid metabolism in 3T3-L1 adipocytes.


Asunto(s)
Fármacos Antiobesidad/farmacología , Butanonas/farmacología , Ácidos Grasos/metabolismo , Lipólisis/efectos de los fármacos , Adiponectina/genética , Adiponectina/metabolismo , Animales , Fármacos Antiobesidad/química , Butanonas/química , Ratones , Células 3T3 NIH , Oxidación-Reducción/efectos de los fármacos
11.
Environ Sci Technol ; 44(6): 2035-41, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20151657

RESUMEN

The heterogeneous reactions of methacrolein (MAC) and methyl vinyl ketone (MVK) on α-Al(2)O(3) surfaces have been studied in a flow reactor using transmission-Fourier Transform Infrared (T-FTIR) spectroscopy to monitor the reaction progress. Unlike SiO(2) particles where MAC and MVK are weakly physisorbed, the results in this work demonstrate that on c-AlO3 particles MAC and MVK are irreversibly adsorbed and can rapidly react on the surface to form various products such as aldehydes, organic acids, hydrogen peroxide, and even higher molecular weight compounds. The initial uptake rates and initial uptake coefficients for MAC and MVK on α-Al(2)O(3) under dry conditions were determined to explore the reactivity of the particles. Furthermore, the effect of water vapor on the heterogeneous reactions was also investigated as a function of relative humidity. Both the heterogeneous uptake and transformation of MAC and MVK on α-Al(2)O(3) were largely suppressed under humid conditions due to the depletion of surface active sites by water molecules. On the basis of experimental results, atmospheric implications of heterogeneous reactions of MAC and MVK were discussed. Our work suggests that heterogeneous reactions on α-Al(2)O(3) can be important sinks for MAC and MVK as well as possible contributors to atmospheric organic aerosol.


Asunto(s)
Acroleína/análogos & derivados , Contaminantes Atmosféricos/química , Óxido de Aluminio/química , Butanonas/química , Material Particulado/química , Acroleína/química , Atmósfera/química , Monitoreo del Ambiente , Humedad , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
12.
J Econ Entomol ; 102(1): 203-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19253638

RESUMEN

Basil oil and its three major active constituents (trans-anethole, estragole, and linalool) obtained from basil (Oscimum basilicum L.) were tested on three tephritid fruit fly species [Ceratitis capitata (Wiedemann), Bactrocera dorsalis (Hendel), and Bactrocera cucurbitae (Coquillett)] for insecticidal activity. All test chemicals acted fast and showed a steep dose-response relationship. The lethal times for 90% mortality/knockdown (LT90) of the three fly species to 10% of the test chemicals were between 8 and 38 min. The toxic action of basil oil in C. capitata occurred significantly faster than in B. cucurbitae but slightly faster than in B. dorsalis. Estragole acted faster in B. dorsalis than in C. capitata and B. cucurbitae. Linalool action was faster in B. dorsalis and C. capitata than in B. cucurbitae. trans-Anethole action was similar to all three species. Methyl eugenol acted faster in C. capitata and B. cucurbitae than in B. dorsalis. When linalool was mixed with cuelure (attractant to B. cucurbitae male), its potency to the three fly species decreased as the concentration of cuelure increased. This was due to linalool hydrolysis catalyzed by acetic acid from cuelure degradation, which was confirmed by chemical analysis. When methyl eugenol (B. dorsalis male attractant) was mixed with basil oil, trans-anethole, estragole, or linalool, it did not affect the toxicity of basil oil and linalool to B. dorsalis, but it did significantly decrease the toxicity of trans-anethole and estragole. Structural similarity between methyl eugenol and trans-anethole and estragole suggests that methyl eugenol might act at a site similar to that of trans-anethole and estragole and serve as an antagonist if an action site exists. Methyl eugenol also may play a physiological role on the toxicity reduction.


Asunto(s)
Ceratitis capitata , Insecticidas/química , Aceites de Plantas/química , Monoterpenos Acíclicos , Derivados de Alilbenceno , Animales , Anisoles/química , Anisoles/aislamiento & purificación , Butanonas/química , Eugenol/análogos & derivados , Eugenol/química , Femenino , Masculino , Monoterpenos/química , Monoterpenos/aislamiento & purificación , Ocimum , Pruebas de Toxicidad
13.
Chem Commun (Camb) ; (7): 912-4, 2005 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-15700079

RESUMEN

Treatment of Cp*(CO)Fe{kappa2(Si,P)-SiMe2PPh2} with methyl vinyl ketone gave a 1,2-addition product, Cp*(CO)Fe{kappa2(Si,P)-SiMe2OCMe(CH=CH2)PPh2}. A linear-type Cp*(CO)2FeSiMe2PPh2 also reacted with the ketone to yield a 1,4-addition product, Cp*(CO)2Fe{kappa1(Si)-SiMe2OC(Me=CHCH2PPh2}, which was further converted to a seven-membered metallacycle, Cp*(CO)Fe{kappa2(Si,P)-SiMe2OC(Me)=CHCH2PPh2}, upon photolysis.


Asunto(s)
Butanonas/química , Hierro/química , Compuestos Organometálicos/química , Compuestos Organometálicos/síntesis química , Fósforo/química , Silicio/química , Cristalografía por Rayos X , Ciclización , Luz , Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares , Compuestos Organometálicos/efectos de la radiación , Sensibilidad y Especificidad , Estereoisomerismo
14.
Water Res ; 38(9): 2258-67, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15142786

RESUMEN

Biological treatment processes used to remove and degrade volatile organic compounds (VOCs) from contaminated gases emitted by industrial operations or waste treatment processes are almost always subjected to transient loading conditions because of the inherently unsteady-state nature of contaminant generating processes. In the study presented here, a laboratory-scale biofilter populated by a mixed culture of fungi was used to study the transient response to various periods of no contaminant loading in a system treating a model waste gas stream containing a mixture of commonly used solvents. The biofilter, packed with cubed polyurethane foam media and operated with an empty bed residence time of 15s, was supplied with a four-component mixture of n-butyl acetate, methyl ethyl ketone, methyl propyl ketone, and toluene at target influent concentrations of 124, 50.5, 174, and 44.6 mg/m(3), respectively. This corresponds to a total VOC loading rate of 94.3g/(m(3)h). Biofilter performance was evaluated over a 94-day period for three loading conditions intended to simulate processes generating contaminated gases only during daytime operation, daytime operation with weekend shutdown periods, and with long term (9-day) shutdown. Results indicate that fungal biofilters can be an effective alternative to conventional abatement technologies for treating solvent contaminated off-gases even under discontinuous loading conditions.


Asunto(s)
Contaminación del Aire/prevención & control , Filtración/métodos , Hongos/metabolismo , Gases/química , Acetatos/química , Acetatos/metabolismo , Contaminantes Atmosféricos/química , Contaminantes Atmosféricos/metabolismo , Biodegradación Ambiental , Butanonas/química , Butanonas/metabolismo , Filtración/instrumentación , Pentanonas/química , Pentanonas/metabolismo , Solventes/química , Factores de Tiempo , Tolueno/química , Tolueno/metabolismo , Volatilización
15.
Biotechnol Bioeng ; 86(4): 468-81, 2004 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-15112299

RESUMEN

In recent years, biofiltration has been increasingly applied as an air pollution control technology to minimize or eliminate emissions of volatile organic compounds from industrial sources and environmental remediation activities. Although the ability of this technology to maintain high removal efficiency during relatively steady loading conditions has been well established for many waste streams, relatively little research has focused on development of operating strategies that could improve treatment performance during transient loading conditions typical of industrial operations. In the research described herein, two operating strategies were evaluated over a period of 295 days in biofilters treating a model waste gas stream containing a two-component mixture of methyl ethyl ketone (MEK) and toluene. One biofilter was operated as a sequencing batch biofilter (SBB), and the other was operated as a conventional continuous-flow biofilter (CFB). During "normal" steady loading conditions, the model waste stream contained MEK concentrations ranging from 80 to 89 ppmv and toluene concentrations ranging from 28 to 30 ppmv. Both biofilter operating strategies resulted in stable long-term performance with greater than 99% contaminant removal during these normal loading conditions. On a regular basis, the influent MEK and toluene concentrations were temporarily increased to five times the normal influent concentration for the duration of 1 h to test performance during transient "shock loading" conditions. Biofilter performance during the model shock loading conditions demonstrate that SBB operating strategies can result in superior treatment in two important areas: (1) overall mass of contaminants removed and (2) minimum instantaneous removal efficiency.


Asunto(s)
Butanonas/química , Filtración/instrumentación , Ingeniería Sanitaria/instrumentación , Tolueno/química , Contaminantes Atmosféricos/química , Biomasa , Carbono/química , Filtración/métodos , Ingeniería Sanitaria/métodos
16.
Bioorg Med Chem Lett ; 14(7): 1729-31, 2004 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-15026059

RESUMEN

The title chiral amine, 3-(4-methoxyphenyl)-1-methylpropylamine 5 has been synthesized from naturally abundant betuligenol 1 in three steps and also in good yield. Furthermore, the versatile intermediate 3 could be manipulated for the preparation of chiral disulphide 7. The amine derivative 5 prepared from (-)-betuligenol showed significant growth inhibition and antifeedant activity.


Asunto(s)
Butanonas/farmacología , Conducta Alimentaria/efectos de los fármacos , Inhibidores de Crecimiento/farmacología , Taxus , Animales , Butanonas/química , Butanonas/aislamiento & purificación , Conducta Alimentaria/fisiología , Inhibidores de Crecimiento/química , Inhibidores de Crecimiento/aislamiento & purificación , Insectos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Hojas de la Planta
17.
J Nat Prod ; 66(3): 447-9, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12662113

RESUMEN

A new methoxylated naphthyl butenone, guieranone A (1), was isolated from the leaves of Guiera senegalensis. Its structure was elucidated as (2E)-1-(1,3,6,8-tetramethoxy-2-naphthyl)but-2-en-1-one, on the basis of spectroscopic data. Also isolated were two known naphthopyrones, 5-methyldihydroflavasperone (2) and 5-methylflavasperone (3). Guieranone (1) exhibited potent antifungal activity against Cladosporium cucumerinum and is the first naphthyl ketone derivative to have been isolated from the family Combretaceae.


Asunto(s)
Antifúngicos/aislamiento & purificación , Butanonas/aislamiento & purificación , Cladosporium/efectos de los fármacos , Combretaceae/química , Naftalenos/aislamiento & purificación , Plantas Medicinales/química , Antifúngicos/química , Antifúngicos/farmacología , Butanonas/química , Butanonas/farmacología , Guinea , Medicinas Tradicionales Africanas , Estructura Molecular , Naftalenos/química , Naftalenos/farmacología , Hojas de la Planta/química
18.
J Agric Food Chem ; 49(8): 3864-6, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11513680

RESUMEN

A practical synthesis of 3-methylnonane-2,4-dione, which is an intense strawlike and fruity flavored compound, has been performed by the aldol condensation of n-hexanal and methyl ethyl ketone, followed by oxidation using sodium hypochlorite in the presence of 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-N-oxide in an overall yield of 59%. The purification of 3-methylnonane-2,4-dione with high purity was performed via copper complexes.


Asunto(s)
Alcanos/síntesis química , Aromatizantes/síntesis química , Cetonas/síntesis química , Aceite de Soja/química , Aldehídos/química , Butanonas/química , Cobre/química , Odorantes , Oxidación-Reducción , Hipoclorito de Sodio/química , Gusto
19.
J Air Waste Manag Assoc ; 47(6): 674-81, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9180063

RESUMEN

Screening of biofiltering material for treatment of volatile organic compounds was performed by using a gas stream containing methyl ethyl ketone (MEK) as a target pollutant. Filtering media (FM) for screening were prepared by blending compost (such as pig and cow manure) and filling material (such as fern chips, wheat bran, and bagasse). Results show that a blend of pig manure/fern chips = 9:1 (wt basis) was superior with respect to the stability of the pH and the water-holding capacity of the FM and in the capacity for treating the target compound. Complete removal of the target compound was obtained at an organic loading of 100 g per cubic meter of filtering media per hour. By using the screened FM for treating MEK and toluene, long-term stability (> 1,200 hours) and complete removal can be obtained at an organic loading of 50 g per cubic meter of FM per hour for either compound.


Asunto(s)
Contaminantes Ambientales/análisis , Filtración/métodos , Animales , Productos Biológicos , Butanonas/química , Bovinos , Contaminantes Ambientales/aislamiento & purificación , Porcinos , Tolueno/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA