title: Analysis of isoflavonoids from leguminous plant extracts by RPHPLC/DAD and electrospray ionization mass spectrometry.
abstract: Traditionally, food is associated with energetic and nutritious characteristics such as sources of carbohydrates, proteins and lipids. Recently, however, foods with bioactive substances such as isoflavones have received great attention. The objective of this study was therefore to evaluate the presence of the isoflavones daidzein, glycitein, genistein and their conjugated forms in grains and leaves of several leguminous plants utilized largely in Brazilian cuisine. Grains used in Peruvian cuisine were also analyzed. After extracting phenolic compounds with methanol (80%), isoflavones as detected by reversed-phase high-performance liquid chromatography/ diode-array detector were only found in chickpeas and soybean. Chickpea extracts showed only the isoflavone genistein at 31 microg/g defatted flour. Detection of these isoflavones was confirmed by electrospray ionization mass and tandem mass spectrometric experiments. For soybean, a distinct distribution of isoflavones was found in hypocotyls and cotyledon. The highest concentration of isoflavones found was approximately 5.9 mg/g for hypocotyls, whereas the total concentration of isoflavone was around 0.4 mg/g for the cotyledons (dry matter). These results indicate that isoflavone concentrations vary within the different tissues of the leguminous species tested.
authors.affiliation: Fazenda Experimental UNOPAR, Universidade Norte do Paraná (UNOPAR), Tamarana/PR, Brazil. claguiar@yahoo.com.br
authors.forename: Claudio L
authors.initials: CL
authors.lastname: Aguiar
authors.forename: Antonio S
authors.initials: AS
authors.lastname: Baptista
authors.forename: Severino M
authors.initials: SM
authors.lastname: Alencar
authors.forename: Renato
authors.initials: R
authors.lastname: Haddad
authors.forename: Marcos N
authors.initials: MN
authors.lastname: Eberlin
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D007887:Fabaceae / Q000737:chemistry*; D005504:Food Analysis / Q000379:methods; D019833:Genistein / Q000032:analysis; D006801:Humans; D007529:Isoflavones / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D007529:Isoflavones; C004742:daidzein; C086566:glycitein; D019833:Genistein