YE Mei,YU Rui-peng,CONG Xin,CHEN Shang-wei,ZHU Song
1.State Key Laboratory of Food Science and Technology，Jiangnan University，Wuxi ，China;
2. Enshi Se－Run Health Tech Development Co.，Ltd.，Enshi ，China
Hits: 1055
Download times: 1053
Abstract:
In this article，selenium（Se） compounds were extracted from Se-enriched Cardamine Violifolia（C. Violifolia） by enzymolysis method，and the known Se species were determined by high performance liquid chromatography－inductively coupled plasma mass spectrometry（HPLC－ICP－MS）．As for the identification of unkown Se compounds，the enzymatic hydrolysate was firstly concentrated by removing impurities with a 3 kDa ultrafiltration centrifuge tube，then freeze－dried，and finally suspended in the initial mobile phase．A Kinetex F5 column（100 mm × 2.1 mm，2.6 μm） was selected for gradient elution．Mobile phases A and B were water and acetonitrile both prepared with 0.1%（volume fraction） formic acid．The unknown Se compounds were screened and identified by ultrahigh performance liquid chromatography－electrospray ionization high resolution tandem mass spectrometry（UPLC－ESI－Triple TOF MS）using unique isotope patterns，TOF MS and TOF MS/MS．The results showed that five Se species in C. Violifolia were determined by HPLC－ICP－MS，namely selenocysteine（SeCys2），methylselenocysteine（MeSeCys），selenomethionine（SeMet），selenite［Se（Ⅳ）］ and selenate［Se（Ⅵ）］．15 other Se compounds，including 7 reported and 8 unreported Se compounds，were identified by UPLC－ESI－Triple TOF MS．The structural formula of three unreported Se compounds，C4H7NO2Se，C5H8O2Se and C7H9NO2Se were proposed.