Separation of anthraquinone compounds from the seed of Cassia obtusifolia L. using recycling counter‐current chromatography

Abstract

Recycling counter-current chromatography (CCC) together with step-gradient CCC and medium-pressure liquid chromatography (MPLC) was employed to separate nine anthraquinone compounds from Cassia obtusifolia L. in this study. The results showed that recycling CCC is a powerful tool for compounds that are difficult to separate with common elution mode. CCC was the better option for crude material while MPLC had advantage for the final tuning. The combination of recycling CCC and MPLC could simplify the method exploring process in the separation process. The structures of these compounds were identified according to their mass spectra, by (1)H-NMR and compared with standard compounds.

Modeling of closed-loop recycling liquid–liquid chromatography: Analytical solutions and model analysis

“…The resolution of the chromatograms of neighboring cycles R sc calculated by Eq. (30) and the resolution of the peaks R s after individual cycles calculated by Eq. (31) are given in Figs.…”

“…The first applications of the recycling principle in CCC were reported in [24,25]. The recycling CCC was successfully implemented for isolation of natural products [26][27][28][29][30][31]. In this paper, we will consider closed-loop isocratic recycling liquid-liquid chromatography.…”

Countercurrent Separation of Natural Products: An Update

“…Three fractions from the first CCS fractionation were further separated by recycling CCS (two to four cycles), also with HEMWat SSs. 275 The separation of apocynin, androsin, and three picrosides from Picrorhiza scrophulariiflora was accomplished with two successive HEMWat (1:2:1:2) and EBuWat (0.1% formic acid) EECCC separations. Finally, picrosides I and III were resolved by six recycling steps with an EWat SS.…”

“… 152 Table S8, Supporting Information , summarizes 22 fractionation protocols including the use of two or three polarity-adjusted step gradients. 37 , 47 , 111 , 126 , 152 , 229 , 267 , 275 , 277 , 298 − 308 …”

Preparative separation of phytosterol analogues from green alga Chlorella vulgaris using recycling counter‐current chromatography

“…Recycling elution mode was generally used in preparative HPLC separation to improve resolution factor, which requires prolonged preparation, but the solvent consumption and the volume separated remain the same. In recent years, the recycling CCC has been successfully applied to separate natural products [25][26][27][28][29][30], the recycling CCC shows its unique advantage in achieving effective separations through preventing stationary phase loss.…”