title: Separation of chlorogenic acid and concentration of trace caffeic acid from natural products by pH-zone-refining countercurrent chromatography.
abstract: Chlorogenic acid and caffeic acid were selected as test samples for separation by the pH-zone-refining countercurrent chromatography (CCC). The separation of these test samples was performed with a two-phase solvent system composed of methyl-tert-butyl-ether/acetonitrile/water at a volume ratio of 4:1:5 v/v/v where trifluoroacetic acid (TFA; 8 mM) was added to the organic stationary phase as a retainer and NH4 OH (10 mM) to the aqueous mobile phase as an eluter. Chlorogenic acid was successfully separated from Flaveria bidentis (L.) Kuntze (F. bidentis) and Lonicerae Flos by pH-zone-refining CCC, a slightly polar two-phase solvent system composed of methyl-tert-butyl-ether/acetonitrile/n-butanol/water at a volume ratio of 4:1:1:5 v/v/v/v was selected where TFA (3 mM) was added to the organic stationary phase as a retainer and NH4 OH (3 mM) to the aqueous mobile phase as an eluter. A 16.2 mg amount of chlorogenic acid with the purity of 92% from 1.4 g of F. bidentis, and 134 mg of chlorogenic acid at the purity of 99% from 1.3 g of crude extract of Lonicerae Flos have been obtained. These results suggest that pH-zone-refining CCC is suitable for the isolation of the chlorogenic acid from the crude extracts of F. bidentis and Lonicerae Flos.
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Lu
authors.forename: Genlai
authors.initials: G
authors.lastname: Dong
authors.forename: Yanxiang
authors.initials: Y
authors.lastname: Gu
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Yun
authors.initials: Y
authors.lastname: Wei
mesh_terms: D001688:Biological Products / Q000737:chemistry*; D002109:Caffeic Acids / Q000302:isolation & purification*; D002726:Chlorogenic Acid / Q000302:isolation & purification*; D003377:Countercurrent Distribution / Q000379:methods*; D037142:Flaveria / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D031239:Lonicera / Q000737:chemistry
chemical_list: D001688:Biological Products; D002109:Caffeic Acids; D002726:Chlorogenic Acid; C040048:caffeic acid
keywords: Caffeic acid; Chlorogenic acid; Flaveria bidentis (L.) Kuntze; Lonicerae Flos; pH-zone-refining countercurrent chromatography