PREPARATIVE ISOLATION AND PURIFICATION OF FIVE FLAVONOIDS FROMPOGOSTEMON CABLINBENTH BY HIGH-SPEED COUNTERCURRENT CHROMATOGRAPHY AND PREPARATIVE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

Abstract

High-speed countercurrent chromatography (HSCCC) and preparative high-performance liquid chromatography (prep-HPLC) were successively used for the separation of pogostone and four flavonoids from Pogostemon cablin (Blanco) Benth. An efficient HSCCC separation was achieved on a two-phase solvent system composed of n-hexane–ethyl acetate–methanol–water (11:5:11:5, v/v/v/v). Three well-separated peaks were obtained in the HSCCC chromatogram. The first and the second fractions each contained two flavonoids which were further separated by preparative HPLC. Consequently, the separation yielded 11.5 mg of 4′, 5-Dihydroxy-3′, 7-dimethoxyflavanone at a purity of 99%, 20.3 mg of 5- Hydroxy-7, 3′, 4′-trimethoxyflavanone at a purity of 98%, 18 mg of 5, 4′-Dihydroxy-3, 7, 3′-trimethoxyflavone at a purity of 96%, and 8 mg of 5-Hydroxy-3, 7, 4′-tetramethoxyflvone at a purity of 98%. The third HSCCC fraction yielded 18.5 mg of pogostone at a purity of 95%. The chemical structures of these compounds were identified by ESI-MSn, 1H-NMR, and 13C-NMR

Isolation and Structure Characterization of Flavonoids

“…The application of other chromatography techniques, such as circular liquid chromatography (CLC), centrifugal preparative thin layer chromatography (CPTLC), high speed counter current chromatography (HSCCC), medium pressure liquid chromatography (MPLC), and so on, has also led to the isolation of numerous structures of flavonoids[39,[47][48][49]. Mostflavonoidswereisolatedwithcombinationofthesetechniqueswithprep.HPLC:four flavonoids (4′,5-dihydroxy-3′,7-dimethoxyflavanone, 5-hydroxy-7,3′,4′-trimethoxyflavanone, 5,4′-dihydroxy-3,7,3′-trimethoxyflavone,and5-hydroxy-3,7,4′-tetramethoxyflvone)wereisolated from Pogostemon cablin (Blanco) Benth.…”

“…Mostflavonoidswereisolatedwithcombinationofthesetechniqueswithprep.HPLC:four flavonoids (4′,5-dihydroxy-3′,7-dimethoxyflavanone, 5-hydroxy-7,3′,4′-trimethoxyflavanone, 5,4′-dihydroxy-3,7,3′-trimethoxyflavone,and5-hydroxy-3,7,4′-tetramethoxyflvone)wereisolated from Pogostemon cablin (Blanco) Benth. using the HSCCC technique with two phase solvent system made of n-hexane-ethyl acetate-methanol-water (11:5:11:5, v/v/v/v) followed byfurtherpurificationonprep.HPLC[39].ThecombinationofHSCCCandsemi-prep.HPLC wasusedtoisolatethreeflavonoidglycosides(orientin,vitexin,quercetin-3-O-neohesperidoside) from Trollius ledebouri Reichb [48]…”

<i>In vitro</i> anti-oxidant and cytotoxic analysis of <i>Pogostemon mollis</i> Benth

“…Earlier studies have revealed many of the active principles in Pogostemon like luteolin, quercetin, ermanine, kaempferol, vanillic acid, benzyl alcohol, kumatakenin, pachypodol, flavons, pogostone, phenylethanoids (acetoside, isoacetoside, crenatoside), ombuine licochalcone and 5,7-dihydroxy-3'44-dimethoxyflavanone, etc. (Li, 2011;Chakrapani et al, 2013). Correspondingly the present study showed the phenolic and flavonoid contents present in P. mollis.…”

Synthesis of pogostone by one-step

“…In traditional process, PO was generally isolated from patchouli oil which was extracted from Herba Pogostemonis. Previous extraction method leaded to low yield of PO (17.6 mg/ kg) [8], which hinders its further study and utilization in pharmacology, clinic, and other fields. Due to PO's low output of direct extraction from natural product, more concern turns to the chemical synthesis.…”