title: Identification and characterization of Se-methyl selenomethionine in Brassica juncea roots.
abstract: The present work shows the identification and characterization of Se-methyl selenomethionine (SeMMet) as an important Se species in Brassica juncea roots when grown in the presence of Se-methionine (SeMet) as the Se source. SeMMet was isolated by liquid chromatography employing two different liquid chromatographic mechanisms: reversed-phase ion-pairing using heptafluorobutyric acid as counter ion and cation exchange using a pyridinium formate gradient (pH 3). Inductively coupled plasma mass spectrometry was used for the detection of Se. SeMMet was characterized by electrospray quadrupole time-of-flight MS in both a synthesized standard and in the roots extract using collision-induced dissociation of the selected ion. Preliminary evidence suggests that Brassica juncea may also produce dimethylselenonium propionate, although to a much lesser extent.
authors.affiliation: Department of Chemistry, University of Cincinnati, PO Box 0172, Cincinnati, OH 45221-0172, USA.
authors.forename: Tyre D
authors.initials: TD
authors.lastname: Grant
authors.forename: María
authors.initials: M
authors.lastname: Montes-Bayón
authors.forename: Danika
authors.initials: D
authors.lastname: LeDuc
authors.forename: Michael W
authors.initials: MW
authors.lastname: Fricke
authors.forename: Norman
authors.initials: N
authors.lastname: Terry
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Caruso
mesh_terms: D002138:Calibration; D002845:Chromatography / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D009149:Mustard Plant / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry*; D012015:Reference Standards; D012643:Selenium / Q000032:analysis* / Q000737:chemistry; D012645:Selenomethionine / Q000032:analysis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D010936:Plant Extracts; D012645:Selenomethionine; D012643:Selenium