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1.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 785-793, 2017.
Artículo en Inglés | WPRIM | ID: wpr-812056

RESUMEN

The roots of Paeoniae lactiflora Pall. are widely consumed as crude drugs in Asian countries due to their remarkable beneficial health effects. The present research was undertaken to illuminate the dynamic changes in metabolites and enzymes and facilitate selection of the harvesting time when the herb can provide optimum health benefits. P. lactiflora roots were analyzed at 12 stages of growth for monoterpenoid glycosides, phenols, nucleosides, nucleobases, amino acids, and polysaccharides by high-performance liquid chromatography with photodiode array detector, ultra-high pressure liquid chromatography coupled with tandem mass spectrometry, and UV spectrophotometry. The enzyme activities of plant β-glucosidases and esterases were determined by UV methods. The total content of monoterpenoid glycosides and phenols peaked in December. For nucleosides and nucleobases, the highest content appeared in April. The maximum phasic accumulation of the total amino acids took place in March, and the content of total polysaccharides reached a peak value in September. December, April, and March were selected as the appropriate harvesting times for producing natural medicinal or health food products. Plant β-glucosidases and esterases showed the highest activity in December and May, respectively. When the activity of β-glucosidase increased, esterase activity decreased, while the contents of oxypaeoniflora and paeoniflorin increased. When esterase activity increased, the contents of benzoylpaeoniflorin, paeoniflorin, and gallic acid decreased. In conclusion, the results from the present study would be useful in determination of the suitable time for harvesting P. lactiflora roots for medicinal purposes.


Asunto(s)
Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos , Química , Estructura Molecular , Paeonia , Química , Raíces de Plantas , Química , Espectrometría de Masas en Tándem
2.
Artículo en Inglés | IMSEAR | ID: sea-162184

RESUMEN

This paper describes the quantitative determination of primary and secondary metabolites present in the flowers of Caryota urens. The primary metabolites are the trace elements such as zinc, copper, boron and molybdenum quantified by AAS (Atomic Absorption Spectrometer) method and minerals such as sodium, potassium and calcium is quantified by flame photometer. Magnesium is quantified by the titrimetric method and nitrogen is quantified by kjeldhal’s method. Iron, Phosphorous, Boron, Molybdenum and Sulphur are quantified by Spectrocolorimetric method. The secondary metabolites are quantified by HPLC method (Alkaloids, terpenoids, liginins, tannins, glycosides, serpentines and saponins). The phenols are quantified by Folin’s Ciocalteau method and flavonoids by spectrophotometric method. This study indicates that the analysed species is a rich source of flavonoids, alkaloids and tannins etc..,

3.
J Biosci ; 1992 Dec; 17(4): 483-489
Artículo en Inglés | IMSEAR | ID: sea-160882

RESUMEN

The onset of biotic stress in the host plants as a result of increased insect population size leads to enhanced levels of secondary metabolites and associated phenolic enzyme activity· Of the three host plants examined, viz. Ricinus communis (castor), Eucalyptus globulus (eucalyptus) and Manihot utilissima (tapioca), castor was the host most preferred by Retithrips syriacus· Despite the fact that tapioca had the highest levels of secondary compounds, thrips infestation persisted· However, fecundity and growth were reduced because of the relatively high levels of primary metabolites. Gallic acid was found to be the most toxic of the phenolic acids, followed by pyrogallol, resorcinol, phloroglucinol and vanillic acid· The less toxic phenolic acids and flavanoids were detected in leaves that harboured thrips, while the preponderance of gallic acid was found in uninfested hosts. Thus the interaction of Retithrips syriacus with the hosts is governed essentially by the biochemical profiles of its hosts, which tend to be altered subsequent to infestation, thus manifesting induced resistance through enhanced production of phenolics.

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