Rational development of a selection model for solvent gradients in single-step separation of ginsenosides from Panax ginseng using high-speed counter-current chromatography

2012 ◽  
Vol 35 (12) ◽  
pp. 1462-1469 ◽  
Author(s):  
Omer Shehzad ◽  
Salman Khan ◽  
In Jin Ha ◽  
Youmie Park ◽  
Yeong Shik Kim
Keyword(s):  
Panax Ginseng ◽  
High Speed ◽  
Single Step ◽  
Selection Model ◽  
Rational Development ◽  
Counter Current

Single-step separation of bioactive flavonol glucosides from Osteomeles schwerinae by high-speed counter-current chromatography

2010 ◽  
Vol 33 (4-5) ◽  
pp. 582-586 ◽  
Author(s):  
Jun Lee ◽  
Dae Sik Jang ◽  
Nam Hee Yoo ◽  
Yun Mi Lee ◽  
Joo-Hwan Kim ◽  
...  
Keyword(s):  
High Speed ◽  
Single Step ◽  
Counter Current

Separation and preparation of two rotenoids from the roots of Derris by high-speed counter-current chromatography

2010 ◽  
Vol 28 (8) ◽  
pp. 813-816
Author(s):  
Wei JI ◽  
Yulan CUI ◽  
Renjuan CHEN ◽  
Xinren LIN ◽  
Qingxin ZHOU ◽  
...  
Keyword(s):  
High Speed ◽  
Counter Current

Isolation and purification of flavones from Murraya exotica L. by high-speed counter-current chromatography

2010 ◽  
Vol 28 (4) ◽  
pp. 383-387 ◽  
Author(s):  
Aiyi PENG ◽  
Xuewei QU ◽  
Hui LI ◽  
Lu GAO ◽  
Bo YU ◽  
...  
Keyword(s):  
High Speed ◽  
Isolation And Purification ◽  
Murraya Exotica ◽  
Counter Current

One-step Separation and Purification of Four Phenolic Acids from Stenoloma chusanum (L.) Ching by Medium-pressure Liquid Chromatography and High-speed Counter-current Chromatography

2019 ◽  
Vol 9 (2) ◽  
pp. 138-143
Author(s):  
Tianyun Li ◽  
Xiling Dai ◽  
Yichen Li ◽  
Guozheng Huang ◽  
Jianguo Cao
Keyword(s):  
Natural Products ◽  
Liquid Chromatography ◽  
Phenolic Acids ◽  
High Speed ◽  
High Efficiency ◽  
Total Phenolic ◽  
Medium Pressure ◽  
Medium Pressure Liquid Chromatography ◽  
One Step ◽  
Counter Current

Background:Stenoloma chusanum (L.) Ching is a Chinese traditional medicinal fern with high total flavonoid and total phenolic content. Traditionally, phenolic compounds were separated by using column chromatography, which is relatively inefficient. </P><P> Objective: This study aims to use an efficient method to separate natural products from S. chusanum by Medium-Pressure Liquid Chromatography (MPLC) and High-Speed Counter-Current Chromatography (HSCCC).Methods:In the present research, firstly, a sample (2.5 g) from the dichloromethane extract of S. chusanum was separated by MPLC. Next, fraction P5 was purified by HSCCC with a two-phase solvent system composed of hexane-ethyl acetate-methanol-water (HEMWat) at a volume ratio of 2:4:1:4 (v/v/v/v). </P><P> Result: Four phenolic acids were obtained and their structures were identified by means of NMR and ESI-mass analysis. They were identified as: 1) protocatechuic acid (34 mg, purity 90.1%), 2) syringic acid (66 mg, purity 99.0%), 3) p-hydroxybenzoic acid (5 mg, purity 91.2%) and 4) vanillic acid (6 mg, purity 99.3%).Conclusion:The combination of MPLC and HSCCC is a high-efficiency separation method for natural products. This is the first report with regard to the separation of four phenolic acids in one step by MPLC and HSCCC from S. chusanum (L.) Ching.

scholarly journals Analysis of the Propagation in High-Speed Interconnects for MIMICs by Means of the Method of Analytical Preconditioning: A New Highly Efficient Evaluation of the Coefficient Matrix

2021 ◽  
Vol 11 (3) ◽  
pp. 933
Author(s):  
Mario Lucido
Keyword(s):  
Integral Equation ◽  
Integrated Circuits ◽  
High Speed ◽  
Coefficient Matrix ◽  
Single Step ◽  
Integral Theorem ◽  
Acceleration Technique ◽  
Cauchy Integral Theorem ◽  
Integral Equation Formulation ◽  
High Speed Interconnects

The method of analytical preconditioning combines the discretization and the analytical regularization of a singular integral equation in a single step. In a recent paper by the author, such a method has been applied to a spectral domain integral equation formulation devised to analyze the propagation in polygonal cross-section microstrip lines, which are widely used as high-speed interconnects in monolithic microwave and millimeter waves integrated circuits. By choosing analytically Fourier transformable expansion functions reconstructing the behavior of the fields on the wedges, fast convergence is achieved, and the convolution integrals are expressed in closed form. However, the coefficient matrix elements are one-dimensional improper integrals of oscillating and, in the worst cases, slowly decaying functions. In this paper, a novel technique for the efficient evaluation of such kind of integrals is proposed. By means of a procedure based on Cauchy integral theorem, the general coefficient matrix element is written as a linear combination of fast converging integrals. As shown in the numerical results section, the proposed technique always outperforms the analytical asymptotic acceleration technique, especially when highly accurate solutions are required.

Sign in / Sign up

Export Citation Format

Share Document