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Métodos Terapêuticos e Terapias MTCI
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1.
Arch Pharm Res ; 23(2): 163-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10836744

RESUMO

The effects of modifiers such as methanol, water, diethylamine in methanol (10 v/v %), and diethylamine in water (10 v/v %) were investigated at three different concentrations (1, 5, and 10 v/v %) of the modifiers in supercritical CO2 (SC-CO2) in order to enhance the supercritical fluid extraction (SFE) efficiency of cephalotaxine from Cephalotaxus wilsoniana leaves. Among the modifiers employed, methanol basified with diethylamine was found to greatly enhance the extraction efficiency relative to any other modifiers employed. The results suggest that cephalotaxine in plant matrices may be readily changed from SC-CO2-insoluble salt to SC-CO2-soluble free base by basified modifiers. In addition, SC-CO2 modified with basified methanol could enhance the extraction efficiency of cephalotaxine more than 30% when compared to the conventional organic solvent extraction.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Harringtoninas/isolamento & purificação , Plantas Medicinais/química , Dióxido de Carbono , Cromatografia Líquida de Alta Pressão , Mepesuccinato de Omacetaxina , Indicadores e Reagentes , Espectrometria de Massas , Folhas de Planta/química , Solventes , Espectrofotometria Ultravioleta
2.
J Chromatogr A ; 863(1): 47-55, 1999 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-10591463

RESUMO

The supercritical fluid extraction behaviors of hyoscyamine and scopolamine were investigated and found to be highly dependent upon the chemical nature of the compounds. Free bases of hyoscyamine and scopolamine were freely soluble in supercritical CO2 with increasing temperature and pressure; however, the salts of these alkaloids were not soluble under any experimental conditions. It was found that alkaline modifiers such as methanol basified with diethylamine could enhance the solubilities and extraction yields of these alkaloids from plant matrices as compared to other modifiers.


Assuntos
Atropina/análise , Plantas Medicinais/química , Escopolamina/análise , Cromatografia Gasosa-Espectrometria de Massas , Indicadores e Reagentes , Folhas de Planta/química , Raízes de Plantas/química , Soluções
3.
J Chromatogr Sci ; 37(12): 457-61, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10615592

RESUMO

An investigation of the effect of plant matrix on the supercritical fluid extraction efficiency of five schisandrin derivatives is reported, exhibiting a great difference with respect to extraction efficiency depending on the matrix. Pure supercritical CO2 at 60 degrees C and 34.0 MPa cannot fully recover schisandrin derivatives from the leaves as much as from the other matrices. Only 36.9% of these compounds are extracted from leaves of Schisandra chinensis by supercritical CO2 in comparison with organic solvent extraction. However, more than 80% of schisandrin derivatives are obtained from both stem and fruit parts. Ethanol addition also shows a different effect depending on plant matrix; that is, CO2 modified with 10% ethanol could enhance the yield of schisandrin derivatives from leaves by four times when compared with that of pure CO2, but it has little effect on both stems and fruits.


Assuntos
Ciclo-Octanos , Etanol/química , Lignanas/química , Plantas Medicinais/química , Compostos Policíclicos/química , Dióxido de Carbono/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Indicadores e Reagentes , Extratos Vegetais/análise , Folhas de Planta/química , Caules de Planta/química , Solventes
4.
Planta Med ; 64(5): 482-3, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17253269

RESUMO

Supercritical fluid extraction (SFE) was utilized to extract podophyllotoxin from the roots of Dysosma pleiantha. The extraction was carried out in the temperature range of 40-80 degrees C and the pressure range of 13.6-34.0 MPa with supercritical carbon dioxide. However, podophyllotoxin was not sufficiently extracted by pure supercritical carbon dioxide. Methanol was used as modifier to enhance the extraction yield of podophyllotoxin. As a result, SFE produced a higher recovery of podophyllotoxin than conventional 95% ethanol extraction.

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