Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 14(1): 16027, 2024 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992035

RESUMO

Pfaffia glomerata (Spreng.) Pedersen has among its main bioactive compounds saponins, with the phytoestroid ß-ecdysone as its chemical marker. In this study, pressurized liquid extraction (PLE), a green extraction technique used to obtain bioactive compounds from plants, was employed to extract beta-ecdysone from P. glomerata leaves, stems, and roots. The 22 factorial design was used with the variables temperature (333 K and 353 K) and flow rate (1.5 and 2 mL min-1), pressure (300 Bar), time (60 min), and solvent [ethanol and distilled water (70:30 (v/v)] were kept constant for all parts of the plant. The results of experimental responses demonstrated that the factors temperature and flow rate significantly interfere with the yields of leaf (0.499%), root (0.65%) and stem (0.764%) extracts. The latter presented presents the highest yield compared to the other parts of the plant. HPLC results showed the presence of beta-ecdysone in all parts of the plant with concentrations of ß-ecdysone 86.82, 76.53 and 195.86 mg L-1 to leaf, root and stem, respectively. FT Raman results exhibited typical peaks of beta-ecdysone, such as 3310 cm-1, 1654 cm-1, and 1073 cm-1 for all plant parts. Another interesting result was the presence of the peak at 1460 cm-1 in the PLE root extract can be associated with selenium. This foundational knowledge confirms that the PLE extraction process was efficient in obtaining the chemical marker of Pfaffia glomerata in all plant parts.


Assuntos
Extratos Vegetais , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Extratos Vegetais/análise , Raízes de Plantas/química , Folhas de Planta/química , Extração Líquido-Líquido/métodos , Caules de Planta/química , Pressão , Temperatura , Amaranthaceae/química
2.
Food Chem ; 365: 130466, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34247048

RESUMO

Organic food consumption has increased significantly over time. This contributes to the increased demand and price of this kind of food. Among the organic products, cinnamon stands out for its characteristic flavor and bioactive compounds. Thus, the work aimed to verify the potentials of attenuated total reflectance Fourier transform mid-infrared spectroscopy (ATR-FT-MIR) coupled with Parallel Factor Analysis (PARAFAC) for evaluation of cinnamon organic samples. As result, the proposal is feasible in the differentiation of organic cinnamon powder, in which ATR-FT-MIR coupled with PARAFAC showed the differentiation of organic from non-organic ones on the scores mode, the precision at repeatability level on one loading mode, and the spectral region, on the other loading mode, above 2600 cm-1 was related to the differentiation of the organic and non-organic samples.


Assuntos
Cinnamomum zeylanicum , Paladar , Análise de Fourier , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Opt Lett ; 33(15): 1720-2, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18670515

RESUMO

We apply thermal-lens (TL) spectrometry to measure the angular dependence of the TL effect on colquiriite single crystals. The experiments were performed with LiSrAlF(6) and LiSrGaF(6) using a two-beam mode-mismatched configuration. The results show that it is possible to minimize the TL effect by selecting the appropriate crystal orientation. Our data also show that the anisotropy of the linear thermal expansion coefficient drives the amplitude of the TL effect, including the inversion from focusing to defocusing as the crystal orientation angle tends to the c-axis direction. The results may be useful for those working to develop a high-power laser using LiSrAlF(6)(:Cr) and LiSrGaF(6)(:Cr) single crystals, allowing for optimization of the designed laser cavity.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA