title: Inclusion effect and structural basis of cyclodextrins for increased extraction of medicinal alkaloids from natural medicines.
abstract: The enhancing effects of alpha-, beta-, and gamma-cyclodextrins (CyDs) on the aqueous extraction of ephedrine and berberine from the natural medicines were investigated in HPLC analysis, and the greatest effect was observed for beta- and gamma-CyDs. To clarify the structural basis of such an increased extraction effect with beta-CyD, possible interaction modes of (1R,2S)-ephedrine with alpha-, beta-, and gamma-CyDs were investigated using molecular dynamic simulations in an aqueous solution system. It was shown that the wrapping model of ephedrine by beta-CyD is the most compact and thus increases the solubility most effectively, compared with those by other CyDs. The same mode could be possible for the greatest effect of gamma-CyD on the extraction of berberine from natural medicines. This clearly shows that CyDs are useful additives for the effective extraction of bioactive alkaloids from natural medicines.
authors.affiliation: Kobe Pharmaceutical University, Motoyama Kitamachi, Kobe, Japan. kamigami@kobepharma-u.ac.jp
authors.forename: Miyoko
authors.initials: M
authors.lastname: Kamigauchi
authors.forename: Kazuko
authors.initials: K
authors.lastname: Kawanishi
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Ohishi
authors.forename: Toshimasa
authors.initials: T
authors.lastname: Ishida
mesh_terms: D000470:Alkaloids / Q000302:isolation & purification*; D001599:Berberine / Q000737:chemistry / Q000302:isolation & purification; D001688:Biological Products / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003505:Cyclodextrins / Q000737:chemistry*; D004809:Ephedrine / Q000737:chemistry / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D010946:Plants, Medicinal / Q000737:chemistry; D013329:Structure-Activity Relationship
chemical_list: D000470:Alkaloids; D001688:Biological Products; D003505:Cyclodextrins; D001599:Berberine; D004809:Ephedrine