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1.
Molecules ; 28(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37241816

RESUMO

Effects of processing and extraction solvents on antioxidant properties and other characteristics were evaluated for ten medicinal plant species originating from two different localities and two production years. A combination of spectroscopic and liquid chromatography techniques possessed data for multivariate statistics. Water, 50% (v/v) ethanol, and dimethyl sulfoxide (DMSO) were compared to select the most suitable solvent for the isolation of functional components from the frozen/dried medicinal plants. DMSO and 50% (v/v) ethanol were evaluated as more efficient for phenolic compounds and colorants extraction, while water was more useful for element extraction. Drying and extraction of herbs with 50% (v/v) ethanol was the most appropriate treatment to ensure a high yield of most compounds. The satisfactory differentiation of herbs (61.8-100%) confirmed the significant effect of the processing, geographical, and seasonal factors on target functional component concentrations. Total phenolic and total flavonoid compounds content, total antioxidant activity expressed as TAA, yellowness, chroma, and browning index were identified as the most important markers for medicinal plant differentiation.


Assuntos
Plantas Medicinais , Solventes/química , Plantas Medicinais/química , Estações do Ano , Extratos Vegetais/química , Dimetil Sulfóxido , Antioxidantes/química , Etanol/química , Fenóis/química , Água , Cromatografia Líquida , Análise Multivariada
2.
Molecules ; 24(22)2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31726737

RESUMO

Chilling influences the growth and metabolism of plants. The physiological response and acclimatization of genotypes in relation to stress stimulus can be different. Two sage cultivars: 'Icterina' and 'Purpurascens' were subjected to 4 °C and 18 °C (control), and sampled between the 5th and 14th day of the treatment. Ascorbate peroxidase (APX) activity was up-regulated in chilled 'Purpurascens' on the 14th day, while guaiacol peroxidase (GPX) activity increased on the 10th and 12th day in relation to the control. GPX activity of the control 'Icterina' was frequently higher than chilled plants, and chilling did not affect APX activity of that cultivar. Catalase activity remained stable in both sage cultivars. Chilled 'Purpurascens' showed a significant increase in total phenolics contents on the 5th, 7th, and 12th day and in total antioxidant capacity on the 5th and 10th day as compared to the control for respective sampling days. Higher malondialdehyde content was found in chilled plants on the 12th, or 14th day, differences reached 26-28% of the controls. Chilling caused significant decrease in dry matter content. The stress response was more stable and effective in 'Icterina', while more dynamic changes were found for 'Purpurascens'. Based on our results, we propose to use 'Purpurascens' for targeted stress-induced studies and 'Icterina' for field applications.


Assuntos
Antioxidantes/metabolismo , Temperatura Baixa , Resposta ao Choque Frio/genética , Metabolismo Energético , Fenômenos Fisiológicos Vegetais , Salvia officinalis/fisiologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
3.
Molecules ; 22(7)2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28726757

RESUMO

Basil (Ocimum L.) species are used as medicinal plants due to their essential oils exhibiting specific biological activity. The present work demonstrated that both the variety and season/conditions of cultivation had a significant effect on (i) the produced amount (extraction yield), (ii) qualitative, as well as (iii) quantitative profile of basil essential oil. Among studied basil varieties, a new variety, 'Mánes', was characterized for the first time. Based on our quantitative evaluation of GC-MS profiles, the following chemotypes and average concentrations of a main component were detected in the studied basil varieties: 'Ohre', 'Lettuce Leaf', 'Purple Opaal', 'Dark Green' (linalool, 5.99, 2.49, 2.34, 2.01 mg/mL, respectively), and 'Mammolo Genovese', 'Mánes', 'Red Rubin' (eucalyptol, 1.34, 0.96, 0.76 mg/mL, respectively). At the same time, when considering other compounds identified in GC-MS profiles, all the studied varieties, except from 'Lettuce Leaf', were methyl eugenol-rich with a strong dependence of the eugenol:methyl eugenol ratio on the seasonal changes (mainly solar irradiation, but also temperature and relative humidity). More complex and/or variable (depending on the season and cultivation) chemotypes were observed with 'Lettuce Leaf' (plus estragole, 2.27 mg/mL), 'Dark Green' (plus eucalyptol, 1.36 mg/mL), 'Mammolo Genovese' (plus eugenol, 1.19 mg/mL), 'Red Rubin' (plus linalool and eugenol, 0.46 and 0.56 mg/mL, respectively), and 'Mánes' (plus linalool and eugenol, 0.58 and 0.40 mg/mL, respectively). When considering superior extraction yield (ca. 17 mL·kg-1, i.e., two to five times higher than other examined varieties) and consistent amounts (yields) of essential oil when comparing inter-seasonal or inter-year data (RSD and inter-year difference in mean yield values ˂2.5%), this new basil variety is very promising for use in the pharmaceutical, food, and cosmetic industries.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Ocimum basilicum/química , Óleos Voláteis/análise , Folhas de Planta/química , Monoterpenos Acíclicos , Derivados de Alilbenzenos , Anisóis/análise , Cicloexanóis/análise , Eucaliptol , Eugenol/análogos & derivados , Eugenol/análise , Monoterpenos/análise , Ocimum , Óleos de Plantas/análise
4.
Molecules ; 17(6): 6672-83, 2012 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-22728361

RESUMO

On a global scale, people are demanding more attractive and tasty food. Both the quality of foodstuffs and aesthetic aspects contribute to the appearance of consumed meals. The attraction and appeal of individual dishes could be enhanced by edible flowers. New information concerning the composition and nutritional value of edible flowers is also important and represents a sufficient reason for their consumption. The aim of this study is to contribute to the popularization of some selected edible flowers of ornamental plants involving altogether 12 species. The flowers were used to determine their antioxidant capacity, which fluctuated between 4.21 and 6.96 g of ascorbic acid equivalents (AAE)/kg of fresh mass (FM). Correlation coefficients between antioxidant capacity and the contents of total phenolics and flavonoids were r² = 0.9705 and r² = 0.7861, respectively. Moreover, the results were supplemented with new data about the mineral composition of edible flowers (mostly, not found in the available literature). The highest levels of mineral elements were observed in the flowers of species Chrysanthemum, Dianthus or Viola. The most abundant element was potassium, the content of which ranged from 1,842.61 to 3,964.84 mg/kg of FM.


Assuntos
Flores/química , Minerais/química , Plantas Comestíveis/química , Antioxidantes/química , Flavonoides/química , Humanos , Valor Nutritivo , Fenóis/química
5.
Pharmacogn Mag ; 6(21): 26-33, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20548933

RESUMO

UNLABELLED: A licorice infusion (LI) and its major constituents were investigated for their capacity to stimulate the activation and the cell cycle progression of human lymphocytes, measured by the CD69 expression and DNA content, respectively. The chemical profile of LI was determined by high-performance liquid chromatography-diode array detection (HPLC-DAD). RESULTS: Two major components of LI were identified as liquiritin (1) and glycyrrhizin (2); total flavones and flavonols were shown as its minor constituents. The LI (100-800 mug/ml) stimulated the expression of CD69 on lymphocytes in a concentration-independent manner. Values of the activation index (AI) of total lymphocytes treated with LI (100-800 mug/ml) did not differ significantly among them (P < 0.05), but were 50% lower than the AI value exhibited by cells treated with phytohemagglutinin (PHA). The LI showed a similar effect on T cells, but on a lower scale. Compounds 1 and 2 (12-100 mug/ml) did not stimulate the CD69 expression on lymphocytes. The LI, 1 and 2 showed no meaningful effect on cell cycle progression of lymphocytes. The experimental data indicates that LI stimulates the activation of lymphocytes as a result of a proliferation-independent process. This finding suggests that LI could be considered as a potential specific immune stimulator.

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