title: Selenium transformation studies during broccoli (Brassica oleracea) growing process by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS).
abstract: Selenium uptake and transformation was studied in Se-enriched Broccoli (Brassica olearacea). Plants were grown in hydroponic culture and exposed during 40 days to Na2SeO3 (1 mg L(-1)). After growing, the plants were harvested and their different parts (roots, stems and fruit) were analyzed by ICP-MS or LC-ICP-MS. Se-species were identified and quantified after enzymatic extraction by using both an anion exchange (PRP-X100), and a size exclusion/ion exchange (Shodex Asahipak) chromatographic columns. Selenium translocation and transformation Se species in plants was studied through the Se-speciation in root, stem and fruit. After 40 days of exposure, selenomethionine was the major species found in roots, however, Se-methylselenocysteine was the main species found in the fruit, suggesting Broccoli as a source of this important selenoamino acid in human diet. However, the degree of meal processing influences the stability of Se-aminoacids. Speciation studies in boiled Broccoli and in the extraction water were also carried out. This experiment revealed a noticeable degradation of Se-methylselenocysteine in the boiled Broccoli fruit. Proteins soluble in Tris-HCl were analyzed by two-dimensional chromatography coupled to ICP-MS. The results obtained contribute not only to a deeper understanding of Se accumulation mechanisms by plants but also to further functional food complements preparation and the effect of food processing on species stability.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
authors.forename: Zoyne
authors.initials: Z
authors.lastname: Pedrero
authors.forename: Daniel
authors.initials: D
authors.lastname: Elvira
authors.forename: Carmen
authors.initials: C
authors.lastname: Cámara
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Madrid
mesh_terms: D001937:Brassica / Q000737:chemistry / Q000254:growth & development; D002853:Chromatography, Liquid / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D010936:Plant Extracts / Q000032:analysis / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry / Q000254:growth & development; D012639:Seeds / Q000737:chemistry / Q000254:growth & development; D012643:Selenium / Q000032:analysis* / Q000737:chemistry; D013054:Spectrophotometry, Atomic / Q000379:methods*
chemical_list: D010936:Plant Extracts; D012643:Selenium