RESUMO
Urine is one of the biological matrices most used for detecting human contamination, as it is representative and easily obtained via noninvasive sampling. This study proposes a fast, accurate, and ecological method based on liquid-liquid microextraction with low-temperature partition (µLLE/LTP). It was validated to determine nine pesticides (lindane, alachlor, aldrin, chlorpyrifos, dieldrin, endrin, DDT, bifenthrin, and permethrin) in human urine, in association with gas chromatography coupled with mass spectrometry (GC-MS). The technique was optimized through a factorial design. The best conditions for the simultaneous extraction of the analytes comprised the addition of 600 µL of water and 600 µL of acetonitrile (extracting solvent) to a 500-µL urine sample, followed by vortexing for 60 s. By freezing the samples for 4 h, it was possible to extract the pesticides and perform the extract clean-up simultaneously. The parameters selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy were used to appraise the performance of the method. Good values of selectivity and linearity (R2 > 0.990), LOQ (0.39-1.02 µg L-1), accuracy (88-119% recovery), and precision (%CV ≤ 15%) were obtained. The µLLE/LTP-GC-MS method was applied to authentic urine samples collected from volunteers in Southeast Brazil.
Assuntos
Clorpirifos , Microextração em Fase Líquida , Resíduos de Praguicidas , Praguicidas , Clorpirifos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Resíduos de Praguicidas/análise , Praguicidas/análiseRESUMO
This study investigates the acute anti-inflammatory activity of Mangifera indica L. leaf extract and mangiferin in the liver of rats fed a cafeteria diet. This study was a randomized longitudinal experimental study. The animals were divided into three groups - Control: cafeteria diet (CD); Extract: CD + leaf extract (250 mg kg-1); and Mangiferin: CD + mangiferin (40 mg kg-1). Body weight and food intake were measured every week. On day eight, mRNA and protein expression of inflammatory markers were evaluated in the liver. Also, liver weight, SOD activity and malondialdehyde concentration were measured. Treatment for only eight days with mango leaf extract and mangiferin increased SOD activity. Mangiferin intake increased the mRNA expression of PPAR-α and HSP72. The leaf extract treatment enhanced PPAR-α mRNA expression. Mangiferin and leaf extract consumption caused a lower concentration of NFκB (p65) in nuclear extracts, and greater IL-10 mRNA and protein levels. This study highlights the potential of acute treatment with mango leaf extract and mangiferin to prevent liver inflammation caused by fat-rich diets. These results indicate a new use for a product that has low cost, is found in great amounts, and is not routinely used.
Assuntos
Anti-Inflamatórios/administração & dosagem , Hepatopatias/tratamento farmacológico , Mangifera/química , Extratos Vegetais/administração & dosagem , Animais , Dieta Hiperlipídica/efeitos adversos , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Hepatopatias/etiologia , Hepatopatias/genética , Hepatopatias/imunologia , Masculino , Malondialdeído/imunologia , PPAR alfa/genética , PPAR alfa/imunologia , Fitoterapia , Folhas de Planta/química , RatosRESUMO
BACKGROUND: The predatory nematophagous fungus Arthrobotrys sinensis (SF53) produces three proteases with nematicidal activity when grown on solid media culture. However, the proteolytic profile produced by this fungus, when grown in liquid culture medium remains unknown. FINDINGS: Thus, the objective of this work was to evaluate the production of proteases from nematophagous fungus Arthrobotrys sinensis in liquid medium and its nematicidal activity on first stage larvae of A. vasorum. Proteases were obtained in its crude form, using Whatman no.1 filter paper, followed by centrifugation for 5 min at 10 × g and 4°C. A zymogram was performed with co-polymerized casein in an acrylamide gel as substrate. An in vitro assay to evaluate the nematicidal action of the proteases of A. sinensis (SF53) produced in liquid medium on A. vasorum L1 was conducted. By the analysis of the zymogram, it was observed a single halo at the beginning of digestion of the gel, suggesting that the three proteases of SF53 are produced in an enzymatic complex of large molecular weight. Regarding nematicidal activity, within 24 hours, the proteases produced in liquid medium of A. sinensis (SF53) showed a percentage reduction of 64% on the number of L1 of A. vasorum. CONCLUSION: In the present work, it is suggested that the three proteases of SF53 are produced in an enzymatic complex and was also demonstrated that these enzymes were effective in destroying A. vasorum L1.
Assuntos
Angiostrongylus/efeitos dos fármacos , Antinematódeos/farmacologia , Ascomicetos/química , Proteólise , Animais , Ascomicetos/enzimologia , Larva/efeitos dos fármacos , Peptídeo Hidrolases/farmacologiaRESUMO
Using a 2(3) experimental design, liquid-liquid extraction with low temperature partitioning (LLE-LTP) was optimized and validated for analysis of three carbamates (aldicarb, carbofuran and carbaryl) in water samples. In this method, 2.0 mL of sample is placed in contact with 4.0 mL of acetonitrile. After agitation, the sample is placed in a freezer for 3 h for phase separation. The organic extract is analyzed by high performance liquid chromatography with ultraviolet detection (HPLC-UV). For validation of the technique, the following figures of merit were evaluated: accuracy, precision, detection and quantification limits, linearity, sensibility and selectivity. Extraction recovery percentages of the carbamates aldicarb, carbofuran and carbaryl were 90%, 95% and 96%, respectively. Even though extremely low volumes of sample and solvent were used, the extraction method was selective and the detection and quantification limits were between 5.0 and 10.0 microg L(-1), and 17.0 and 33.0 microg L(-1), respectively.
Assuntos
Carbamatos , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Praguicidas , Poluentes Químicos da Água , Aldicarb/análise , Carbamatos/análise , Carbaril/análise , Carbofurano/análise , Fracionamento Químico/métodos , Limite de Detecção , Resíduos de Praguicidas/análise , Poluentes Químicos da Água/análiseRESUMO
This paper describes a new gas-chromatography with electron capture detection (GC-ECD) method for determination of some pyrethroids in milk samples. The extraction of the pyrethroids was carried out by liquid-liquid extraction with clean-up by precipitation at low temperature, without additional stages for removal of fat interferences. The method was efficient with recoveries of 93.0+/-0.1% for cipermethrin and 84.0+/-0.3% for deltamethrin. The quantification limits were 0.75 microg L(-1) for both pyrethroids. The method was simple, of easy execution, and used only small quantities of organic solvent. After optimization and validation, the method was used for the determination of residues of the pyrethroids cipermethrin and deltamethrin in milk and in lactea drink commercialized in Viçosa (MG, Brazil). Some samples presented contamination with deltamethrin at levels below the maximum contamination limits established by the FAO.