title: Profiling and quantification of isoflavonoids in kudzu dietary supplements by high-performance liquid chromatography and electrospray ionization tandem mass spectrometry.
abstract: The kudzu vine (Pueraria sp.) is a rich source of isoflavones. Dietary supplements based on kudzu have become commercially available. In the present study, liquid chromatography coupled with negative and positive electrospray ionization tandem mass spectrometry (MS/MS) and diode array detection (DAD) has been used for the detection and characterization of isoflavonoids in kudzu dietary supplements (KDS). The MS/MS spectrum of the protonated ion of puerarin showed characteristic product ions of the C-glycoside unit itself, whereas daidzin generated an abundant Y(0)(+) aglycon ion in its product ion spectrum. A base peak due to the loss of 120 Da [M + H - 120](+) is the diagnostic ion for C-glycosides. Neutral loss scans allowed for the detection of other C- and O-glycosides in the methanolic extract of KDS, and their structures have been proposed. The concentration of isoflavonoids in the methanolic extract of commercially available KDS was quantified by using DAD-HPLC. Puerarin, rather than daidzin, was the most abundant component (8.44-30.60 mg/capsule) in commercially available KDS.
authors.affiliation: Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
authors.forename: Jeevan K
authors.initials: JK
authors.lastname: Prasain
authors.forename: Kenneth
authors.initials: K
authors.lastname: Jones
authors.forename: Marion
authors.initials: M
authors.lastname: Kirk
authors.forename: Landon
authors.initials: L
authors.lastname: Wilson
authors.forename: Michelle
authors.initials: M
authors.lastname: Smith-Johnson
authors.forename: Connie
authors.initials: C
authors.lastname: Weaver
authors.forename: Stephen
authors.initials: S
authors.lastname: Barnes
mesh_terms: D002851:Chromatography, High Pressure Liquid; D019587:Dietary Supplements / Q000032:analysis*; D007529:Isoflavones / Q000032:analysis*; D029908:Pueraria / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D007529:Isoflavones