Characterization of selenium species in Brazil nuts by HPLC-ICP-MS and ES-MS.
J Agric Food Chem
; 50(20): 5722-8, 2002 Sep 25.
Article
em En
| MEDLINE
| ID: mdl-12236705
Brazil nuts have been classified as the foodstuffs that contain the highest level of unadulterated selenium, an essential trace element that appears to prevent cancer. To date, characterization of the selenium species in brazil nuts has not yet been investigated. In this work, various sample preparation approaches, including microwave extractions and enzymatic treatments, are examined with the goal of species preservation and subsequent selenium speciation; of these approaches, an enzymatic treatment with Proteinase K proved most effective. High-performance liquid chromatography (HPLC) separation strategies and inductively coupled plasma mass spectrometry (ICP-MS) detection schemes will also be presented. Extracts are evaluated against available standards for the commercially obtainable seleno-amino acids, selenomethionine (SeMet), selenoethionine (SeEt), and selenocystine (SeCys); selenomethionine was demonstrated to be the most abundant of these seleno-amino acids. Further characterization of unidentified selenium-containing peaks is attempted by the employment of several procedures, including electrospray-mass spectrometry (ES-MS). A peptide structure was identified; however, this was considered a tentative proposal due to the large background produced by the extremely complicated brazil nut matrix.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Selênio
/
Espectrometria de Massas
/
Cromatografia Líquida de Alta Pressão
/
Compostos Organosselênicos
/
Magnoliopsida
/
Cistina
Tipo de estudo:
Guideline
País/Região como assunto:
America do sul
/
Brasil
Idioma:
En
Revista:
J Agric Food Chem
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
Estados Unidos
País de publicação:
Estados Unidos