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1.
J Sep Sci ; 41(9): 2092-2101, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29385309

RESUMO

The objective of this study was to develop a consecutive preparation method for the isolation and purification of hainanmurpanin, meranzin, and phebalosin from leaves of Murraya exotica L. The process involved supercritical fluid extraction with CO2 , solvent extraction, and two-step high-speed countercurrent chromatography. Pressure, temperature, and the volume of entrainer were optimized as 27 MPa, 52°C, and 60 mL by response surface methodology in supercritical fluid extraction with CO2 , and the yield of the crude extracts was 7.91 g from 100 g of leaves. Subsequently, 80% methanol/water was used to extract and condense the three compounds from the crude extracts, and 4.23 g of methanol/water extracts was obtained. Then, a two-step high-speed countercurrent chromatography procedure was developed for the isolation of the three target compounds from methanol/water extracts, including conventional high-speed countercurrent chromatography for further enrichment and consecutive high-speed countercurrent chromatography for purification. The yield of concentrates from high-speed countercurrent chromatography was 2.50 g from 4.23 g of methanol/water extracts. Finally, the consecutive high-speed countercurrent chromatography produced 103.2 mg of hainanmurpanin, 244.7 mg of meranzin, and 255.4 mg of phebalosin with purities up to 97.66, 99.36, and 98.64%, respectively, from 900 mg of high-speed countercurrent chromatography concentrates in one run of three consecutive sample loadings without exchanging a solvent system.


Assuntos
Cumarínicos/isolamento & purificação , Murraya/química , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico , Distribuição Contracorrente , Extratos Vegetais/química , Pressão , Solventes , Temperatura
2.
J Sci Food Agric ; 98(7): 2498-2506, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29023749

RESUMO

BACKGROUND: Supercritical fluid extraction with CO2 (SFE-CO2 ) was utilized for extraction of capsaicin (CA) and dihydrocapsaicin (DHCA) from Capsici Fructus, and then a two-step enrichment method for separating capsaicinoids from SFE-CO2 extracts was developed. The process involved extraction with aqueous methanol and crystallization by alkali extraction and acid precipitation. Finally, a consecutive high-speed countercurrent chromatography (HSCCC) separation method was successfully applied in the purification of CA and DHCA from capsaicinoid crystal. RESULTS: The extraction pressure, extraction temperature and volume of co-solvent were optimized at 33 MPa, 41 °C and 75 mL, respectively, using response surface methodology; the extraction rates of CA and DHCA were about 93.18% and 93.49%, respectively. 407.43 mg capsaicinoid crystal was isolated from the SFE-CO2 extracts obtained from 100 g capsicum powder by the two-step enrichment method. About 506 mg and 184 mg CA and DHCA with purities up to 98.31% and 96.68%, respectively, were obtained from 1 g capsaicinoid crystal in one HSCCC of three consecutive sample loadings without exchanging any solvent system. CONCLUSIONS: This method comprising SFE-CO2 , a two-step enrichment and HSCCC was efficient, powerful and practical for the large-scale preparation of CA and DHCA from Capsici Fructus with high purity and high yield. © 2017 Society of Chemical Industry.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/isolamento & purificação , Capsicum/química , Cromatografia com Fluido Supercrítico/métodos , Distribuição Contracorrente/métodos , Extratos Vegetais/isolamento & purificação , Capsaicina/química , Frutas/química , Extratos Vegetais/química
3.
J Sep Sci ; 40(6): 1273-1282, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28106330

RESUMO

10-Deacetylbaccatin III, an important semisynthetic precursor of paclitaxel and docetaxel, can be extracted from Taxus wallichiana Zucc. A process for the isolation and purification of 10-deacetylbaccatin III (1), baccatin III (2), and 7ß-xylosyl-10-deacetyltaxol (3) from the leaves and branches of Taxus wallichiana Zucc. via macroporous resin column chromatography combined with high-speed countercurrent chromatography or reversed-phase flash chromatography was developed in this study. After fractionation by macroporous resin column chromatography, 80% methanol fraction was selected based on high-performance liquid chromatography and liquid chromatography with mass spectrometry qualitative analysis. A solvent system composed of n-hexane, ethyl acetate, methanol, and water (1.6:2.5:1.6:2.5, v/v/v/v) was used for the high-speed countercurrent chromatography separation at a flow rate of 2.5 mL/min. The reversed-phase flash chromatography separation was performed using methanol/water as the mobile phase at a flow rate of 3 mL/min. The high-speed countercurrent chromatography separation produced compounds 1 (10.2 mg, 94.4%), 2 (2.1 mg, 98.0%), and 3 (4.6 mg, 98.8%) from 100 mg of sample within 110 min, while the reversed-phase flash chromatography separation purified compounds 1 (9.8 mg, 95.6%) and 3 (4.9 mg, 97.9%) from 100 mg of sample within 120 min.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Extratos Vegetais/química , Taxoides/isolamento & purificação , Taxus/química , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente
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