title: Isolation from beer and structural determination of a potent stimulant of gastrin release.
abstract: Beer was subjected to five successive chromatographic procedures to isolate the gastrin release-inducing activity, guided by bioassay of the fractions in anaesthetized Donryu rats. The procedures were: (1) hydrophobic interaction chromatography (aqueous effluent with an HP20 column); (2) weak cation-exchange chromatography (1 M acetic acid eluate with a CM Sephadex C-25 column); (3) gel filtration (methanol eluate with a Sephadex LH-20 column); (4) same as (2); (5) high-performance liquid chromatography (YMC-Pack ODS-AM with 7% acetonitrile-0.01 M HCl). The active component finally isolated had a specific activity approximately 10000 times higher than that of beer. It was identified by means of mass, 1H- and 13C-nuclear magnetic resonance spectral analyses as N-methyltyramine (NMT). The dose of NMT giving maximal gastrin-releasing activity was 25 microg/kg, and the 50% effective dose was approximately 10 microg/kg on oral administration to rats. NMT was isolated and identified as a gastrin release inducer in beer. Its concentration in beer is sufficient to account for most of the activity of beer.
authors.affiliation: Technical Development Department, Suntory Limited, Mishima-Gun, Osaka, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yokoo
authors.forename: H
authors.initials: H
authors.lastname: Kohda
authors.forename: A
authors.initials: A
authors.lastname: Kusumoto
authors.forename: H
authors.initials: H
authors.lastname: Naoki
authors.forename: N
authors.initials: N
authors.lastname: Matsumoto
authors.forename: T
authors.initials: T
authors.lastname: Amachi
authors.forename: Y
authors.initials: Y
authors.lastname: Suwa
authors.forename: H
authors.initials: H
authors.lastname: Fukazawa
authors.forename: H
authors.initials: H
authors.lastname: Ishida
authors.forename: K
authors.initials: K
authors.lastname: Tsuji
authors.forename: H
authors.initials: H
authors.lastname: Nukaya
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000302:isolation & purification*; D000818:Animals; D001515:Beer / Q000032:analysis*; D005755:Gastrins / Q000378:metabolism*; D008297:Male; D051381:Rats; D014439:Tyramine / Q000031:analogs & derivatives* / Q000302:isolation & purification
chemical_list: D000316:Adrenergic alpha-Agonists; D005755:Gastrins; C036244:methyl-4-tyramine; D014439:Tyramine