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1.
Braz. J. Pharm. Sci. (Online) ; 56: e18499, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285512

RESUMO

Lignosus rhinocerotis (tiger milk mushroom) is widely used by the indigenous people of Malaysia as a traditional remedy. The present study was carried out in order to evaluate the antioxidant, cytotoxic and anti-neuroinflammatory activities of L. rhinocerotis extract on brain microglial cells (BV2). The antioxidant activity was evaluated by 2,2-diphenyl-1-picryhydrazyl (DPPH•), 2,2'-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS•+) scavenging assays, and ferric reducing antioxidant power (FRAP). The FRAP, DPPH and ABTS•+ scavenging capacities of the TE3 fraction were 420.77 mg FE/g, 58.01%, and 7%, respectively. The cytotoxic activity was determined by MTS assay. The in vitro model of anti-neuroinflammatory property was evaluated by measuring the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced BV2 cells. The TE3 fraction showed a significant NO reduction at 1 to 100 µg/mL. The TE3 fraction down-regulated inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) genes while it upregulated heme oxygenase (HO-1) and NADPH quinone acceptor oxidoreductase-1 (NQO-1) genes. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) transcription was also activated. The chemical component of the active fraction (TE3) was identified by gas chromatography-mass spectrometry (GCMS). Overall, the BV2 in vitro model anti-neuroinflammatory activity of L. rhinocerotis may be caused by the lipid constituents identified in the fraction


Assuntos
Técnicas In Vitro/métodos , Células/classificação , Agaricales/classificação , Inflamação/tratamento farmacológico , Lipídeos/efeitos adversos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Antioxidantes/farmacologia
2.
Braz. J. Pharm. Sci. (Online) ; 53(2): e14093, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839486

RESUMO

ABSTRACT Samburá is the botanical pollen nectar agglutinated by salivary secretions of bees. Stingless bee pollen samples were collected in three periods of the year in Monsenhor Gil town, PI, Brazil, for extraction of volatile constituents by different techniques, analyzed by gas chromatography-mass spectrometry (GC-MS) and the palynological analysis used to identify the dominant pollen. Among the volatile compounds identified, kaur-16-ene, methyl and ethyl hexadecanoate, methyl linoleate and heneicosane were identified more frequently in the studied parameters: period of sample collection and extraction techniques used. The palynological analysis identified the pollen of Mimosa caesalpiniifolia Benth. as the dominant pollen in all samples studied.


Assuntos
Abelhas/classificação , Compostos Orgânicos Voláteis/farmacologia , Pólen/metabolismo , Mimosa/classificação , Cromatografia Gasosa-Espectrometria de Massas/instrumentação
3.
Braz. J. Pharm. Sci. (Online) ; 53(3): e00260, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889387

RESUMO

ABSTRACT In this study essential oil of the aerial parts of Heracleum persicum a spice widely used in Iran was isolated by conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) techniques. The extraction yield was determined and the chemical compositions of essential oils were identified by the application of gas chromatography/mass spectrometry (GC/MS). The antioxidant activity was determined by two different methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and oven test methods. Although the main compounds of essential oils by the both extraction methods were similar, the essential oil extracted by HD with lower extraction efficiency showed more diverse compounds. The evaluation of antioxidant activity of the essential oil measured by delay in sunflower oil oxidation indicated that the antioxidant activity was dependent on the concentration which increased when higher concentrations of the essential oils were applied. The results of DPPH radical assay also indicated that the percentage of inhibition increased with increasing of essential oil concentration and IC50 value for essential oil extracted by MAHD method was obtained 1.25 mg/mL. Therefore the Heracleum persicum essential oil might be recommended for use as a flavoring agent and a source of natural antioxidants in functional foods, formulation of the supplements and in medicinal due to numerous pharmacological activities.


Assuntos
Óleos Voláteis/análise , Heracleum/efeitos adversos , Heracleum/química , Antioxidantes/análise , Componentes Aéreos da Planta/classificação , Estufas para Plantas/métodos , Oxidação , Óleo de Girassol/efeitos adversos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação
4.
Indian J Exp Biol ; 2015 Mar; 53(3): 170-176
Artigo em Inglês | IMSEAR | ID: sea-158410

RESUMO

In order to better understand the biochemical interactions and to identify new biomarkers for plant resistance against insects, we proposed a suitable lipophilic profiling method for insects and their host plants. The critical components of GC-MS based analysis are: sample amount, extraction, derivatization, temperature gradient, run time, and identification of peaks. For lipophilic metabolite profiling of maize and sorghum, and their insect pest, spotted stem borer larvae, we recommend 100 mg sample weight for seeds and insect samples (whole insect body), and 200 mg for seedlings. Maize and sorghum seeds required less time for fat extraction in comparison to their seedlings and the pest fed on these seedlings. GC-MS was standardized for better separation and intensity of peaks using different temperature gradients in the range of 180-300 C. A total of 48 lipophilic compounds encompassing various classes based on their functional groups such as fatty acids, fatty alcohols, hydrocarbons, sterols and terpenoids, vitamin derivative, etc. were separated in the seedlings (30), seeds (14), and the pest (26) in the retention time range of 3.22 to 29.41 min. This method could be useful to study nutritional aspects of different field crops in relation to various stresses apart from the analysis of lipophilic compounds for better understanding of insect-plant interactions.


Assuntos
Animais , Gorduras/análise , Gorduras/isolamento & purificação , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Álcoois Graxos/análise , Álcoois Graxos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/normas , Lipídeos/análise , Lipídeos/isolamento & purificação , Mariposas/química , Mariposas/crescimento & desenvolvimento , Extratos Vegetais/química , Plântula/química , Sementes/química , Sorghum/química , Esteróis/análise , Esteróis/isolamento & purificação , Terpenos/análise , Terpenos/isolamento & purificação , Zea mays/química
5.
São Paulo; s.n; s.n; dez. 10, 2014. 135 p. tab, graf, ilus.
Tese em Português | LILACS | ID: biblio-836776

RESUMO

Os antidepressivos pertencem a uma importante classe de medicamentos investigados na toxicologia forense. Em casos de amostras provenientes de cadáveres, o intervalo entre o óbito e a obtenção da espécie biológica pode proporcionar a redistribuição postmortem destes fármacos. Com o objetivo de elucidar esse fenômeno, métodos analíticos foram desenvolvidos e aplicados utilizando sangue total (ST), humor vítreo (HV) e fígado. Para as amostras de ST e HV, o método de extração escolhido e validado foi a microextração em fase líquida (LPME) trifásica. Fibras ocas constituídas de polipropileno, com a extensão de 8 cm cada, foram tratadas com o solvente orgânico dodecano (fase orgânica), resultando em um membrana com permeabilidade seletiva. No lúmen destas fibras, adicionou-se ácido fórmico 0,1 mol/L (fase aceptora). Em frasco de fundo chato com 5 mL de capacidade, pipetou-se 3,5 mL de NaOH 0,1 mol/L (fase doadora) e 0,5 mL de ST ou HV. Ao término da extração, as amostras foram introduzidas no GC-MS, sem a necessidade de reações de derivatização. O estudo com ST contemplou os antidepressivos amitriptilina (AMI), nortriptilina (NTR), imipramina (IMI), desipramine (DES), clomipramina (CLO), desmetilclomipramina (DMC), fluoxetina (FLU) e norfluoxetina (NFL). Os limites de quantificação para estas substâncias ficaram inferiores aos níveis terapêuticos (20 ng/mL). As médias dos coeficientes de variação intradia e interdia foram, respectivamente, de 9,7 e 9,8%. As curvas de calibração apresentaram linearidade entre as concentrações de 20 até 1200 ng/mL. A validação do parâmetro integridade da diluição assegurou a mensuração de quantidades superiores ao limite apresentado na curva de calibração. O método foi aplicado em sete amostras reais postmortem e em apenas um caso foi observada uma diferença significativa (300%) entre os valores quantificados no ST periférico e central. Os antidepressivos tricíclicos AMI, NTR, IMI e DES foram avaliados no HV e o efeito matriz foi detectado para os dois últimos analitos. O método foi otimizado e validado utilizando solução salina adicionada de AMI e NTR. O limite de detecção igual a 5 ng/mL, foi obtido com a redução da voltagem da fonte de íons do espectrômetro de massa para 50 eV. Coeficientes de variação foram inferiores a 15%. Os procedimentos validados foram aplicados em seis amostras reais de HV. A relação encontrada entre os valores obtidos no ST periférico e HV foi de aproximadamente 0,1. A extração acelerada por solvente (ASE) e, posteriormente, a extração em fase sólida (SPE) foram as técnicas de separação dos analitos da matriz fígado. Ao término das citadas extrações, os antidepressivos foram analisados no GC-MS. Para esta matriz sólida, são necessários mais estudos, pois os valores encontrados nos ensaios analíticos estão em desacordo com as diretrizes utilizadas na validação dos métodos


Antidepressants belong to an important class of drugs investigated in forensic toxicology. In cases of samples from corpses, the interval between death and obtaining the biological specimens can provide the postmortem redistribution of these drugs. Aiming to elucidate this phenomenon, analytical methods were developed and applied using whole blood (WB), vitreous humor (VH) and liver. For samples of WB and HV, the extraction method chosen and validated was the three-phase liquid phase microextraction (LPME). Hollow fibers consist of polypropylene, with a length of 8 cm each were treated with dodecane organic solvent (organic phase) resulting in a membrane with selective permeability. Into the lumen of these fibers was added formic acid 0.1 mol/ L (acceptor phase). In the vial containing 3.5 mL of NaOH 0.1 mol / L (donor phase) was spiked 0.5 ml of biological fluids (WB or VH). Subsequently, the samples were injected in GC-MS without derivatization reactions. The study of the ST included antidepressants amitriptyline (AMI), nortriptyline (NTR), imipramine (IMI), desipramine (DES), clomipramine (CLO), desmethylclomipramine (DMC), fluoxetine (FLU) and norfluoxetine (NFL). The quantification limits for these substances were below the therapeutic levels (20 ng / ml). The mean coefficients of variation and separate intradays were respectively 9.7 and 9.8%. The calibration curves showed linearity between concentrations of 20 to 1200 ng / mL. The validation of the integrity of the dilution parameter assured measurement higher than the limit shown in the calibration curve quantities. The method was applied to seven real postmortem samples and in one case a significant difference (300%) between the measured values in the peripheral and central ST was observed. The tricyclic antidepressants AMI, NTR, IMI and DES were evaluated in VH and the matrix effect was detected in the last two analytes. The method was optimized and validated using saline spiked AMI and NTR. The limit of detection (5 ng/ml) was obtained by reducing the voltage of the ion source of the mass spectrometer 50 eV. Coefficients of variation were below 15%. The procedures were validated in six real samples of HV. The relationship found between the values obtained in the peripheral ST and HV was approximately 0.1. Accelerated solvent extraction (ASE) and subsequently the solid phase extraction (SPE) were the techniques of separation of analytes liver matrix. At the end of the cited extractions, antidepressants were analyzed in GC-MS. To this solid tissue, further studies are needed, because the values found in the analytical tests were not in accordance with the guidelines used in the validation of the methods


Assuntos
Humanos , Mudanças Depois da Morte , Biotransformação , Antidepressivos/análise , Corpo Vítreo/patologia , Cromatografia Gasosa , Toxicologia Forense/instrumentação , Microextração em Fase Líquida , Medicina Legal , Cromatografia Gasosa-Espectrometria de Massas/instrumentação
6.
Arch. venez. pueric. pediatr ; 73(1): 20-26, ene.-mar. 2010.
Artigo em Espanhol | LILACS | ID: lil-589184

RESUMO

El paraquat es un plaguicida agricola bipiridilo, cuyos efectos tóxicos más severos son año hepato-renal y fibrosis pulmonar irreversible. Se reportan dos casos de intoxicación en niños, por ingestión accidental de paraquat; ellos desarrollaron sialorrea, vómitos azul verdoso, lesión digestiva cáustica. dificultad respiratoria, daño hepato-renal, alteraciones radiológicas y presencia de paraquat en orina y sangre. Ambos pacientes recibieron el tratamiento disponible entre 24-48 horas despues de la ingestion y tuvieron una evolución satisfactoria. El tratamiento consistió basicamente en diálisis gastrointestinal, diuresis forzada ácida, N-acetilcisteína y dexametasona.


Paraquat is a bipyridyl agricultural pesticide, whose more severe effects are hepatic-renal damage and irreversible pulmonary fibrosis. Two children with paraquat accidental poisoning are reported; they developed syalorrhea, blue greenish vomiting, caustic digestive injury, breathing difficulty, liver and kidney damage, radiographic changes and presence of paraquat in blood and urine. Both patients received the available treatment 24-48 hours after ingetion and had a satisfactory autcome. The consisted basically of gatrointestinal dialysis, acidic forced diuresis, N-acetylcysteine and dexamethasone.


Assuntos
Humanos , Masculino , Lactente , Pré-Escolar , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Esofagite/diagnóstico , Fibrose Pulmonar/complicações , Hemoperfusão/métodos , Insuficiência Respiratória/diagnóstico , Paraquat/toxicidade , Acidentes/tendências , Herbicidas/intoxicação , Herbicidas/toxicidade
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