On-line hyphenation of counter-current chromatography and medium pressure liquid chromatography for preparative separation of euphorbia factors from Euphorbia lathyris L.

Euphorbia lathyris L, one of the medicinal plants of the family Euphorbiaceae, contains a series of diterpenoids known as euphorbia factors which show pharmacological activities against HIV-1 replication, vasoconstriction, and cancer proliferation [1]. However, its chemical complexity and diversity make pure compounds isolation difficult. This study presents a developed method, two-dimentional hyphenation of counter-current chromatography (CCC) and medium pressure liquid chromatography (MPLC) for the preparative separation of euphorbia factors from Euphorbia lathyris. The extraction solution of Euphorbia lathyris seeds was directly and continuously injected into the CCC column (CCC-DCI, [2]) and concentrated target compounds were firstly separated by gradient elution of CCC. The CCC and MPLC were hyphenated via ten-port injection valve and the overlapped mixture from CCC separation was secondly isolated by MPLC. Euphorbia factors L1 (58 mg), L2 (35 mg), L3 (62 mg), L_7a (4 mg), L_7b (18 mg), L8 (11 mg), and L9 (3 mg) were successfully obtained in a single CCC-MPLC separation. The purity determination and structural identification of the isolated compounds were performed by LC-UV, LC-MS/MS, and 1D NMR.

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[2] Song K, Lee KJ, Kim YS. J Chromatogr A 2017; 1489: 107 – 114

[3] Li Y, Wang N, Zhang M, Ito Y, Zhang H, Wang Y, Guo X, Hu P. Anal Chem 2014; 86: 3373 – 3379