title: Monoamine oxidase inhibitory coumarins from the aerial parts of Dictamnus albus.
abstract: The methanol extract from the aerial parts of Dictamnus albus was active in inhibiting monoamine oxidase (MAO) from the mouse brain. Activity-guided fractionation led to the isolation of four known coumarins, 7-(6'R-hydroxy-3', 7'-dimethyl-2'E, 7'-octadienyloxy) coumarin (1), auraptene (2), umbelliferone (3), and xanthotoxin (4), as active compounds along with an inactive alkaloid, skimmianine (5). Compounds 1 and 2 inhibited MAO activity in a concentration-dependent manner with IC50 values of 0.7 and 1.7 microM, respectively. Compounds 1 and 2 showed a slight and potently selective inhibitory effect against MAO-B (IC50 0.5 and 0.6 microM, respectively) compared to MAO-A (IC50 1.3 and 34.6 microM, respectively). According to kinetic analyses derived by Lineweaver-Burk reciprocal plots, compounds 1 and 2 exhibited a competitive inhibition to MAO-B.
authors.affiliation: College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea.
authors.forename: Seon Hwa
authors.initials: SH
authors.lastname: Jeong
authors.forename: Xiang Hua
authors.initials: XH
authors.lastname: Han
authors.forename: Seong Su
authors.initials: SS
authors.lastname: Hong
authors.forename: Ji Sang
authors.initials: JS
authors.lastname: Hwang
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Hwang
authors.forename: Dongho
authors.initials: D
authors.lastname: Lee
authors.forename: Myung Koo
authors.initials: MK
authors.lastname: Lee
authors.forename: Jai Seup
authors.initials: JS
authors.lastname: Ro
authors.forename: Bang Yeon
authors.initials: BY
authors.lastname: Hwang
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000201:enzymology; D003010:Clorgyline / Q000494:pharmacology; D003374:Coumarins / Q000494:pharmacology*; D036905:Dictamnus / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology; D008995:Monoamine Oxidase / Q000378:metabolism; D008996:Monoamine Oxidase Inhibitors; D012642:Selegiline / Q000494:pharmacology; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
chemical_list: D003374:Coumarins; D008996:Monoamine Oxidase Inhibitors; D012642:Selegiline; D008995:Monoamine Oxidase; D003010:Clorgyline