title: Chemical characterisation and speciation of organic selenium in cultivated selenium-enriched Agaricus bisporus.
abstract: The selenium concentration in Agaricus bisporus cultivated in growth compost irrigated with sodium selenite solution increased by 28- and 43-fold compared to the control mushroom irrigated solely with water. Selenium contents of mushroom proteins increased from 13.8 to 60.1 and 14.1 to 137 μgSe/g in caps and stalks from control and selenised mushrooms, respectively. Selenocystine (SeCys; detected as [SeCys]2 dimer), selenomethionine (SeMet), and methyl-selenocysteine (MeSeCys) were separated, identified and quantified by liquid chromatography-electrospray ionisation-mass spectrometry from water solubilised and acetone precipitated proteins, and significant increases were observed for the selenised mushrooms. The maximum selenoamino acids concentration in caps and stalks of control/selenised mushrooms was 4.16/9.65 μg/g dried weight (DW) for SeCys, 0.08/0.58 μg/g DW for SeMet, and 0.031/0.10 μg/g DW for MeSeCys, respectively. The most notable result was the much higher levels of SeCys accumulated by A. bisporus compared to SeMet and MeSeCys, for both control and selenised A. bisporus.
authors.affiliation: Department of Agriculture & Food Systems, Melbourne School of Land & Environment, The University of Melbourne, Parkville, Victoria 3010, Australia.
authors.forename: Tebo
authors.initials: T
authors.lastname: Maseko
authors.forename: Damien L
authors.initials: DL
authors.lastname: Callahan
authors.forename: Frank R
authors.initials: FR
authors.lastname: Dunshea
authors.forename: Augustine
authors.initials: A
authors.lastname: Doronila
authors.forename: Spas D
authors.initials: SD
authors.lastname: Kolev
authors.forename: Ken
authors.initials: K
authors.lastname: Ng
mesh_terms: D000364:Agaricus / Q000737:chemistry* / Q000254:growth & development* / Q000378:metabolism; D003553:Cystine / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D016566:Organoselenium Compounds / Q000032:analysis* / Q000378:metabolism; D012643:Selenium / Q000032:analysis* / Q000378:metabolism; D017279:Selenocysteine / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D012645:Selenomethionine / Q000032:analysis* / Q000378:metabolism
chemical_list: D016566:Organoselenium Compounds; D017279:Selenocysteine; C009226:selenocystine; D003553:Cystine; D012645:Selenomethionine; D012643:Selenium; C002979:selenomethylselenocysteine
keywords: Agaricus bisporus; Methyl-selenocysteine; Selenium-enriched mushrooms; Selenocysteine; Selenomethionine; Selenoproteins