Isolation and purification of isoflavonoids from Rhizoma Belamcandae by two‐dimensional preparative high‐performance liquid chromatography with column switch technology

Abstract

A two-dimensional column-switching system without sample loop trapping, where two columns were operated via a six-port switching valve, was employed in the isolation and purification of five isoflavonoids from Rhizoma Belamcandae: tectoridin, iridin, tectorigenin, irigenin and irisflorentin. The introduction of the six-port switching value, instead of a sample loop, assured 100% recovery from the first dimension to the second, and the injection volumes of the second dimension were not restricted. Two configurations were tested in this study. In the first mode, only one column was used in the second dimension and two 'heart-cutting' fractions were transported to the same second-dimensional column. In the second mode, two parallel columns were used in the second dimension and two fractions were transported to the two columns. Between the two configurations, the one with two second dimensional columns had double sample size, better resolution and one more purified compound. Both two-dimensional configurations consumed less solvent with even greater efficiency and shorter cycle time compared with conventional gradient methods. All of the isoflavonoids were isolated at high purities of greater than 95% with yields of above 82%.

Fluorescence spectroscopy and docking study in two flavonoids, isolated tectoridin and its aglycone tectorigenin, interacting with human serum albumin: a comparison study

“…Tectoridin (TD) is the 7‐glucoside of tectorigenin (TG), and both compounds are widely distributed in plants, such as Iris tectorum , Belamcanda chinensis and Pueraria thunbergiana . TD and TG have been shown to have many pharmacological activities .…”

Multidimensional preparative liquid chromatography to isolate flavonoids from bergamot juice and evaluation of their anti-inflammatory potential

“…In the last decade some articles described prep‐MDLC techniques for the purification of complex samples. Most of them are focused on the isolation of bioactive compounds from plants of traditional Chinese medicines . Other articles focused on the purification of complex pharmaceutical samples ; Wong et al.…”

“…Most authors selected an online heart‐cutting approach: The transfer of the fractions eluted from the first dimension (1D) to the second dimension (2D) column occurred thanks to a six‐port two‐position switching valve placed between the two dimensions. In some cases the switching valve was equipped with a sample loop , otherwise the change of valve position would lead to a coupling in series of the two preparative columns . Recent studies used 2D countercurrent chromatography for purification of complex samples.…”

Isolation and purification of diastereoisomeric flavonolignans from silymarin by binary‐column recycling preparative high‐performance liquid chromatography

“…The column‐switching system outperforms preparative HPLC with a single column as it allows the coeluted components of interest to be transported to another column for further separation . In our previous work, the column‐switching system where two columns were switched directly without sample loop trapping was successfully applied in the isolation and purification of iridoid glycosides from Gardenia jasminoides Ellis, isoflavonoids from Rhizoma Belamcandae, and lignans from Magnolia biondii Pamp . In this study, modified binary‐column recycling preparative HPLC systems where two columns were switched via one or two six‐port switching valves was established and applied to isolate and purify silybin A, silybin B, isosilybin A, and isosilybin B from silymarin.…”