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1.
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
2.
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
3.
Pharmacogn Mag ; 12(Suppl 2): S165-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27279702

RESUMO

BACKGROUND: Kadsurae Caulis and Spatholobi Caulis have very similar Chinese names. Their commodities were hard to distinguish because their stems were very alike after dried and processed. These two herbal drugs were often mixed in clinical use. OBJECTIVE: Authenticity assurance is crucial for quality control of herbal drugs. Therefore, it is essential to establish a method for identifying the two herbs. MATERIALS AND METHODS: In this paper, we used the DNA barcoding technology, based on the internal transcribed spacer 2 (ITS2) regions, to differentiate Kadsurae Caulis and Spatholobi Caulis. RESULTS: The ITS2 of these two herbs were very different. They were successfully differentiated using the DNA barcoding technique. CONCLUSIONS: DNA barcoding was a promising and reliable tool for the identification of medicinal plants. It can be a powerful complementary method for traditional authentication. SUMMARY: The internal transcribed spacer 2 (ITS2) regions between Kadsurae Caulis and Spatholobi Caulis varied considerably, totally 139 variable sitesSample 1 was not Kadsurae Caulis as it labeled, but it should be Spatholobi Caulis in fact based on ITS2 regionThe secondary structure can also separate Kadsurae Caulis and Spatholobi Caulis effectivelyDNA barcoding provided an accurate and strong prove to identify these two herbs. Abbreviations used: CTAB: hexadecyltrimethylammonium bromide, DNA: deoxyribonucleic acid, ITS2:internal transcribed spacer 2, PCR: polymerase chain reaction.

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