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1.
J Environ Sci Health B ; 57(3): 165-175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35175180

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/análise
2.
Food Funct ; 10(8): 4861-4867, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31334539

RESUMO

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 , Ratos
3.
Exp Parasitol ; 197: 16-19, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30615860

RESUMO

Spent mushroom compost (SMC) is a residue generated in edible mushrooms production, such as Hypsizygus marmoreus. Its genome was recently sequenced, demonstrating cuticle-degrading protease genes. The present work aims to investigate the proteases from H. marmoreus spent mushroom compost (SMC) by verifying its action on nematode larvae. The extraction of the crude extract directly with water from H. marmoreus SMC proved to be efficient for proteases obtainment, with proteolytic activity of 195.36 ±â€¯18.38 U g-1 of compound. Moreover, the zymogram and SDS-PAGE indicated the presence of two proteases with estimated molecular weights of 30.2 and 33.7 kDa. Due to the protease activity present in H. marmoreus SMC extract, there was a significant reduction in the number of Panagrellus redivivus and L3 in treated group compared to control group (p < 0.01), with 52% and 26% of reduction, respectively. A0A151VWY3 mature protein is composed of 296 amino acid residues, exhibiting molecular weight and pI of 29.5 kDa and 6.72. A0A151WD28 mature protein is composed of 343 amino acid residues, exhibiting molecular weight and pI of 34.4 kDa and 8.04. In the present work it was demonstrated that SMC from H. marmoreus has easily extracted protease content, presenting two proteases, possibly with cuticle-degrading activity, which had significant nematicidal effect on P. redivivus and bovine infective larvae.


Assuntos
Agaricales/enzimologia , Compostagem , Peptídeo Hidrolases/metabolismo , Rabditídios/efeitos dos fármacos , Agaricales/genética , Animais , Bovinos , Misturas Complexas/química , Misturas Complexas/isolamento & purificação , Misturas Complexas/farmacologia , Eletroforese em Gel de Poliacrilamida , Fezes/parasitologia , Larva/efeitos dos fármacos , Peso Molecular , Peptídeo Hidrolases/química , Rabditídios/isolamento & purificação , Strongyloidea/efeitos dos fármacos , Strongyloidea/isolamento & purificação , Trichostrongyloidea/efeitos dos fármacos , Trichostrongyloidea/isolamento & purificação
4.
3 Biotech ; 8(3): 167, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29527454

RESUMO

The objective of this study was to purify, characterize, and phylogenetically and structurally analyze the dextranase produced by the fungus Pochonia chlamydosporia. Dextranase produced by the fungus P. chlamydosporia was purified to homogeneity in two steps, with a yield of 152%, purification factor of 6.84 and specific activity of 358.63 U/mg. Its molecular weight was estimated by SDS-PAGE at 64 kDa. The enzyme presented higher activity at 50 °C and pH 5.0, using 100 mM citrate-phosphate buffer, was inhibited by Ag1+, Hg2+, Cu2+, Mg2+, and presented KM of 23.60 µM. Mature dextranase is composed of 585 amino acids residues, with a predicted molecular weight of 64.38 kDa and pI 5.96. This dextranase showed a strong phylogenetic similarity when compared to Trichoderma harzianum dextranase. Its structure consists of two domains: the first composed by 15 ß strands, and the second composed by a right-handed parallel ß-helix.

5.
3 Biotech ; 8(1): 46, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29354357

RESUMO

The objective of this work was to optimize the total cellulase activity of the crude extract cocktails from five white rot fungi produced by solid-state fermentation, by means of the central composite design. The white rot fungi Pleurotus ostreatus PLO 06, Pleurotus eryngii PLE 04, Trametes versicolor TRAM 01, Pycnosporus sanguineus PYC 02 and Phanerochaete chrysosporium PC were tested. For optimization process aiming at the maximum value of total cellulase activity (FPAse), the multi-enzyme cellulase complexes (crude extracts) of each fungus were mixed simultaneously in different proportions. There was increase in FPAse activity for the cocktails formed by the extracts of the five fungi together, compared to the extracts of each fungus alone. The model presented the minimum cocktail of enzymes for maximum total cellulase activity, with 100.00 µL PYC; 100.00 µL PC; 100.00 µL PLO06; 100.00 µL PLE04 and 200 µL TRAM01. The maximum value found was of 304.86 U/L. The result of the cocktails was very relevant, showing that there is an enzymatic complementation in the extracts that should be further studied. Concentrated extract cocktails should also be evaluated for biomass saccharification.

6.
Nutr Hosp ; 33(6): 1424-1429, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-28000476

RESUMO

BACKGROUND: Lecythis pisonis Cambess is commonly known as "castanha de sapucaia" in Brazil. Chemical composition studies revealed that this nut is an excellent source of anti-oxidant minerals and of essential lipids. OBJECTIVE: The aim of the present study is to assess the anti-oxidant and anti-inflammatory effect of Lecythis pisonis Cambess on the brain tissue of Wistar rats. MATERIAL AND METHODS: The animals were divided in four experimental groups (n = 6), total of forty-eight rats. Treatments included the standard diet (AIN-93G) and high-fat food, supplemented with Sapucaianut from 14 to 28 days. The gene expression markers TNF-α, NFkB, ZnSOD and HSP-72 were defined through reverse transcriptase polymerase chain reaction (rtPCR). The anti-oxidant effect was assessed through the thiobarbituric acid-reactive substances (TBARS) and the measurement of the activity performed by superoxide dismutase enzymes. RESULTS: Accordingly, the gene expression of the inflammatory markers NFkB (p65) and TNF-αwas lower in rats fed on diets supplemented with "sapucaia", and they presented significant difference in the Tukey test (p < 0.05). The heat-shock HSP-72 protein and the ZnSOD enzyme raised the gene expression and showed significant statistical difference (p < 0.05) in both groups fed on Sapucaia nut-based diet. CONCLUSION: Thus, the nutritional properties of the Sapucaia nuts perform important neuroprotective activities because they modulated the anti-oxidant activity and the brain tissue inflammatory process in the assessed animals.


Assuntos
Bertholletia/química , Gorduras na Dieta/efeitos adversos , Lecythidaceae/química , Fármacos Neuroprotetores/farmacologia , Animais , Antioxidantes/metabolismo , Química Encefálica/efeitos dos fármacos , Inflamação/prevenção & controle , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
7.
Rev Iberoam Micol ; 32(1): 51-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24071638

RESUMO

BACKGROUND: The dog acts as a reservoir and environmental disseminator of potentially zoonotic parasites. AIMS: The objective of this work was to study the fungus Monacrosporium thaumasium regarding its nematicidal potential in laboratory trials and its proteolytic profile. METHODS: The in vitro test was carried out through two assays (A and B). In assay A, conidia of the fungus N34a were added in positive coprocultures for Angiostrongylus vasorum. In assay B, crude extract (treated group) and distilled water (control group) were added to coprocultures. Next, the proteolytic profile of crude extract of the nematophagous fungus M. thaumasium (NF34a) was revealed by performing a zymogram. RESULTS: There was a reduction (p<0.01) in the averages of larvae recovered from the treated groups (conidia and crude extract) in relation to control groups. The zymogram suggested that the nematophagous fungus M. thaumasium produces a protease of approximately 40 kDa. CONCLUSIONS: The results of this work confirm that the conidia as well as the crude extract of the fungus M. thaumasium may be used to control A. vasorum L1. The proteolytic profile suggested the presence of one protease (Mt1) of approximately 40 kDa that in the future may be used in biological control of L1 of this nematode.


Assuntos
Angiostrongylus/microbiologia , Descontaminação/métodos , Doenças do Cão/parasitologia , Fungos Mitospóricos/fisiologia , Infecções por Strongylida/veterinária , Animais , Reservatórios de Doenças , Cães/parasitologia , Fezes/parasitologia , Proteínas Fúngicas/metabolismo , Larva/microbiologia , Fungos Mitospóricos/enzimologia , Peptídeo Hidrolases/metabolismo , Microbiologia do Solo , Esporos Fúngicos , Infecções por Strongylida/parasitologia , Zoonoses
8.
BMC Res Notes ; 7: 811, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25406419

RESUMO

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/farmacologia
9.
Res Vet Sci ; 97(3): 527-32, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25267285

RESUMO

The present work used Plackett-Burman experimental design to assess the influence of enzymes of nematophagous fungi versus Strongyloides westeri and trichostrongylides larvae and Platynosomum fastosum eggs. The variables studied in the Plackett-Burman design were the proteases and chitinases of AC001 or VC4 as destructive agents of S. westeri and trichostrongylides larvae, and P. fastosum eggs. All tested enzymes had a significant effect (P < 0.05) on the destruction of S. westeri larvae. Furthermore, only VC4 and AC001 proteases showed a significant effect (P < 0.05) on the destruction of trichostrongylides larvae. On the other hand, chitinases of VC4 showed the highest significance (P < 0.05) on the destruction of P. fastosum eggs. It is proposed that statistical planning for the use of enzymes derived from nematophagous fungi is a viable way to elucidate some questions about their mechanism of action.


Assuntos
Ascomicetos/enzimologia , Dicrocoeliidae/fisiologia , Proteínas de Helminto/metabolismo , Strongyloides/fisiologia , Trichostrongyloidea/fisiologia , Animais , Quitinases/metabolismo , Dicrocoeliidae/crescimento & desenvolvimento , Hypocreales/enzimologia , Larva/fisiologia , Óvulo/fisiologia , Peptídeo Hidrolases/metabolismo , Controle Biológico de Vetores , Strongyloides/crescimento & desenvolvimento , Trichostrongyloidea/crescimento & desenvolvimento
10.
Anal Chim Acta ; 671(1-2): 41-7, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20541641

RESUMO

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/análise
11.
Talanta ; 75(5): 1320-3, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18585219

RESUMO

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.


Assuntos
Cromatografia Gasosa/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Inseticidas/análise , Leite/química , Piretrinas/análise , Animais , Brasil , Precipitação Química , Cromatografia Gasosa/instrumentação , Temperatura Baixa , Elétrons , Análise de Alimentos/instrumentação , Humanos , Compostos Orgânicos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química
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