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1.
Int J Anal Chem ; 2018: 2560498, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30627163

RESUMO

The performance of gas chromatography coupled to high-resolution time-of-flight mass spectrometry (GC-HRTofMS) for characterizing geochemical biomarkers from sediment samples was evaluated. Two approaches to obtain the geochemical biomarkers were tested: (1) extraction with organic solvent and subsequent derivatization and (2) in-situ derivatization thermal desorption. Results demonstrated that both approaches can be conveniently applied for simultaneous characterization of many geochemical biomarkers (alkanes, alkanols, sterols, and fatty acids), avoiding conventional time-consuming purification procedures. GC-HRTofMS reduces both sample preparation time and the number of chromatographic runs compared to traditional methodologies used in organic geochemistry. Particularly, the approach based on in-situ derivatization thermal desorption represents a very simple method that can be performed in-line employing few milligrams of sediment, eliminating the need for any sample preparation and solvent use. The high resolving power (m/Δm 50% 25,000) and high mass accuracy (error ≤ 1 ppm) offered by the "zig-zag" time-of-flight analyzer were indispensable to resolve the complexity of the total ion chromatograms, representing a high-throughput tool. Extracted ion chromatograms using exact m/z were useful to eliminate many isobaric interferences and to increase significantly the signal to noise ratio. Characteristic fragment ions allowed the identification of homologous series, such as alkanes, alkanols, fatty acids, and sterols. Polycyclic aromatic hydrocarbons were also identified in the samples by their molecular ions. The characterization of geochemical biomarkers along a sedimentary core collected in the area of Valo Grande Channel (Cananéia-Iguape Estuarine-Lagunar System (São Paulo, Brazil)) provided evidences of environmental changes. Sediments deposited before opening of channel showed dominance of biomarkers from mangrove vegetation, whereas sediments of the pos-opening period showed an increase of biomarkers from aquatic macrophyte (an invasive vegetation).

2.
J Food Sci ; 81(9): C2206-17, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27490163

RESUMO

This study was aimed to assess the effect of time and temperature on the extraction of antioxidant compounds from jabuticaba seeds (Myrciaria cauliflora cv. Sabará), to optimize the solvent proportion (water, ethyl alcohol, and propanone), and to characterize the extract according to the chemical composition, antioxidant, and antimicrobial properties. Proximal composition, total phenolic content (TPC), antioxidant, and antimicrobial activities were analyzed. The optimized solvent ratio of 60% water and 40% propanone provided a mean TPC of 8.65 g GAE/100 g seeds and the antioxidant activity toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) was 82.79% ± 0.50%. Time and temperature parameters did not influence the yield of TPC. The gross seed extract was partially purified and both exhibited a high antioxidant activity and antimicrobial potential toward Gram-positive and Gram-negative bacteria. The purified jabuticaba seed lyophilized extract contained a higher (P < 0.05) TPC, o-diphenols, flavonols, and antioxidant activity measured by the DPPH assay and total reducing capacity as compared to the gross lyophilized extract. Electrospray ionization coupled with tandem mass spectrometry (ESI-MS/MS) data showed the presence of ellagitannins and ellagic acid in the extracts, which are probably the responsible for the antimicrobial and antioxidant activities.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Myrtaceae/química , Extratos Vegetais/química , Sementes/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Ácido Elágico/análise , Ácido Elágico/farmacologia , Flavonóis/química , Flavonóis/farmacologia , Frutas/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/farmacologia , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
3.
J Trace Elem Med Biol ; 33: 37-47, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26653742

RESUMO

The aim of this study was to investigate if purple carrot extract is able to protect against the noxious activities induced by cadmium exposure in multiple organs of rats. For this purpose, histopathological analysis, genotoxicity and oxidative status were investigated in this setting. A total of twenty Wistar rats weighing 250g on the average, and 8 weeks age were distributed into four groups (n=5), as follows: Control group (non-treated group, CTRL); Cadmium group (Cd) and Purple carrot extract groups at 400mg/L or 800mg/L. Histopathological analysis revealed that liver from animals treated with purple carrot extract improved tissue degeneration induced by cadmium intoxication. Genetic damage was reduced in blood and hepatocytes as depicted by comet and micronucleus assays in animals treated with purple carrot extract. SOD-CuZn and cytocrome C gene expression increased in groups treated with purple carrot extract. Purple carrot extract also reduced the 8OHdG levels in liver cells when compared to cadmium group. Taken together, our results demonstrate that purple carrot extract is able to protect against cadmium intoxication by means of reducing tissue regeneration, genotoxicity and oxidative stress in multiple organs of Wistar rats.


Assuntos
Intoxicação por Cádmio/tratamento farmacológico , Daucus carota/química , Mutagênicos/toxicidade , Especificidade de Órgãos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Intoxicação por Cádmio/metabolismo , Ensaio Cometa , Citocromos c/metabolismo , Dano ao DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/patologia , Testes para Micronúcleos , Extratos Vegetais/farmacologia , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas por Ionização por Electrospray , Aumento de Peso/efeitos dos fármacos
4.
Int J Food Sci Nutr ; 66(4): 439-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25835042

RESUMO

The aim of this study was to investigate the phenolic composition of a natural food colourant (G8000™) as well as its effects on plasma markers after 28-day consumption by healthy individuals at a dietary dose (70 g). Parameters of total cholesterol and its fractions, triglycerides and plasma enzymes biomarkers of muscle injury were measured. Major compounds identified in G8000™ by ESI-MS showed the presence of anthocyanins, organic acids, phenolic acids as well as monosaccharides. HDL levels significantly increased from 43 ± 10.2 mg/dL to 95 ± 16.9 mg/dL. LDL levels significantly decreased from 110 ± 40.9 mg/dL to 69 ± 39 mg/dL (p < 0.001). No significant statistical differences (p > 0.05) were observed for total cholesterol, triglycerides and VLDL. After the intake, plasma enzyme CK-MB decreased from 20 ± 12.1 U/L to 10 ± 1.9 U/L while LDH levels increased from 275 ± 124.4 U/L to 317 ± 114.7 U/L (p < 0.005). No significant differences were observed for CK levels. Taken together, dietary intake of natural colourant G8000™ was able to exert beneficial effects on atherosclerosis biomarkers.


Assuntos
HDL-Colesterol/sangue , LDL-Colesterol/sangue , Corantes de Alimentos/farmacologia , Extratos Vegetais/sangue , Extratos Vegetais/farmacologia , Vitis , Adulto , Biomarcadores/sangue , Feminino , Corantes de Alimentos/metabolismo , Humanos , Masculino , Fenóis/sangue , Fenóis/farmacologia , Triglicerídeos/sangue , Adulto Jovem
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