Separation and purification of four compounds from Desmodium styracifolium using off‐line two‐dimensional high‐speed counter‐current chromatography

Abstract

An off-line 2D high-speed counter-current chromatography technique in preparative scale has been successfully applied to separate and purify the main compounds from the ethyl acetate extract of Desmodium styracifolium. A two-phase solvent system composed of n-hexane/ethyl acetate/methanol/water at an optimized volume ratio of 1:2:1:2 v/v/v/v was used. Conventional high-speed counter-current chromatography was used as the first dimension, and the upper phase of the solvent system was used as the stationary phase in the head-to-tail elution mode at a flow rate of 2.0 mL/min and a rotation speed of 900 rpm. Recycling high-speed counter-current chromatography served as the second dimension to separate an impure fraction of the first dimension. A total of four well-separated substances including vanillic acid (1), β-sitosterol (2), formononetin (3), and aromadendrin (4) were obtained, and their purities and structures were identified by HPLC-MS and (1) H NMR spectroscopy. The results illustrated that off-line 2D high-speed counter-current chromatography is an effective way to isolate compounds in complex samples.

Rapid separation of three proanthocyanidin dimers from Iris lactea Pall. var. Chinensis (Fisch.) Koidz by high‐speed counter‐current chromatography with continuous sample load and double‐pump balancing mode

“…According to the polarity of the target compounds, three sets of two‐phase solvent systems including ethyl acetate:methanol: n ‐butanol:water (8:3:1:10, 8:5.2:1:10, v / v / v / v ), ethyl acetate: n ‐butanol:water (9:1:10, 9:1:8, v / v / v ) and ethyl acetate:methanol:water (8:5.2:10, v / v / v ) were tested. As previously reported in the literature, K ‐values of the target compounds in the range of 0.5 to 2 are a prerequisite to get effective HSCCC separation with good resolution and short elution time (Su et al ., ). As it is shown in Table , the solvent system ethyl acetate:methanol: n ‐butanol:water (8:5.2:1:10, v / v / v / v ) provided small K ‐values for the three target compounds ( K 1 = 0.23, K 2 = 0.71 and K 3 = 0.58), which would cause poor peak resolution.…”

Isolation and Purification of Sesquiterpene Lactones from <i>Ixeris sonchifolia</i> (Bunge) Hance by High-Speed Counter- Current Chromatography and Semi-Preparative High Performance Liquid Chromatography

“…Due to the similar structures and largely polarities of ixerin Z and 11,13α-dihydroixerin Z, it is difficult to separate them from complex system in a single HSCCC procedure with these two-phase solvent systems [21]. Thus semipreparative HPLC was chosen to isolate and purify the mixture of ixerin Z and 11, 13α-dihydroixerin Z.…”

Target-guided separation of antioxidants from Semen cassia via off-line two-dimensional high-speed counter-current chromatography combined with complexation and extrusion elution mode

“…Column chromatography (CC) and thin layer chromatography (TLC) have been widely applied to separating NPs for centuries, but those controversial techniques have many drawbacks such as irreversible adsorption, low preparative throughput and low recovery. Recent decades, as a novel liquid-liquid partition chromatography, highspeed counter-current chromatography (HSCCC) has been widely employed for separation of bioactive compounds in NPs [16][17][18][19][20][21]. Due to using support-free liquid stationary phase, drawbacks mentioned above can be effectively eliminated [22].…”