title: Alternating isocratic and step gradient elution high-speed counter-current chromatography for the isolation of minor phenolics from Ormocarpum kirkii bark.
abstract: A total of 14 compounds were isolated from the ethanol bark extract of O. kirkii S. Moore (Fabaceae) by alternating isocratic and step gradient elution high-speed counter-current chromatography (HSCCC) methods, using several solvent systems with reference to the polarity of compounds being purified. The extract was successively fractionated with generic solvent systems including n-hexane-ethanol-water (4:2:2) and ethyl acetate-water (1:1). Resulting fractions were further purified using the following preparative gradient elution consisting of ethyl acetate-n-butanol-water (X:Y:10), (X:Y=9:1 (I); 8:2 (II); 7:3 (III); 6:4 (IV); 5:5 (V); 4:6 (VI) 3:7 (VII) and n-hexane- ethyl acetate-methanol-water (1:X:1:1), X=1, 2, 2.5, 3 solvent systems. Two flavone glycosides, apigenin-6-C-β-d-glucopyranosyl-4'-O-[β-d-glucopyranosyl-(1→5)]-β-d-apiofuranoside (1) and apigenin-6-C-β-d-glucopyranosyl-4'-O-β-d-apiofuranoside (2), and one biflavanone diglycoside 7,7″-di-O-β-d-glucosylliquiritigeninyl-(I-3,II-3)-naringenin (4) were isolated as new compounds along with other 11 known ones. The structures of the isolated compounds were identified by HPLC-UV, ESI-MS, 1D and 2D NMR and comparison with literature data. Thus, over common traditional chromatographic methods, the present study shows that HSCCC is a useful and fast method for natural product research with no losses and lower solvent use.
authors.affiliation: Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté des Sciences, Université de Yaoundé 1, BP 812 Yaoundé, Cameroon; Universidade Federal do Rio de Janeiro, Instituto de Pesquisas de Produtos Naturais, Bl. H, CCS, Iha do Fundão, 21.941-902 Rio de Janeiro, RJ, Brazil.
authors.forename: Eutrophe Le Doux
authors.initials: EL
authors.lastname: Kamto
authors.affiliation: Universidade Federal do Rio de Janeiro, Instituto de Pesquisas de Produtos Naturais, Bl. H, CCS, Iha do Fundão, 21.941-902 Rio de Janeiro, RJ, Brazil.
authors.forename: Tatiane S C
authors.initials: TS
authors.lastname: Carvalho
authors.affiliation: Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté des Sciences, Université de Yaoundé 1, BP 812 Yaoundé, Cameroon.
authors.forename: Joséphine Ngo
authors.initials: JN
authors.lastname: Mbing
authors.affiliation: Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté des Sciences, Université de Yaoundé 1, BP 812 Yaoundé, Cameroon.
authors.forename: Marie C N
authors.initials: MC
authors.lastname: Matene
authors.affiliation: Laboratoire de Pharmacochimie des Substances Naturelles, Département de Chimie Organique, Faculté des Sciences, Université de Yaoundé 1, BP 812 Yaoundé, Cameroon.
authors.forename: Dieudonné E
authors.initials: DE
authors.lastname: Pegnyemb
authors.affiliation: Universidade Federal do Rio de Janeiro, Instituto de Pesquisas de Produtos Naturais, Bl. H, CCS, Iha do Fundão, 21.941-902 Rio de Janeiro, RJ, Brazil. Electronic address: ggleitao@yahoo.com.br.
authors.forename: Gilda G
authors.initials: GG
authors.lastname: Leitão
mesh_terms: D001688:Biological Products / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003377:Countercurrent Distribution / Q000379:methods*; D007887:Fabaceae / Q000737:chemistry*; D047309:Flavones / Q000302:isolation & purification; D006027:Glycosides / Q000302:isolation & purification; D010636:Phenols / Q000302:isolation & purification*; D024301:Plant Bark / Q000737:chemistry*; D012997:Solvents; D013997:Time Factors
chemical_list: D001688:Biological Products; D047309:Flavones; D006027:Glycosides; D010636:Phenols; D012997:Solvents; C043562:flavone
keywords: Biflavonoids; Biscoumarins; Fabaceae; Flavones; Gradient elution CCC; Ormocarpum kirkii