Characteristics And Speciation Analysis Of Selenium In Oats

Selenium is an important micronutrient with a narrow range of intake.Outside this narrow range deficiency disease and toxicity occur.Let inorganic selenium into organic selenium by plants,and enter the food chain,can improves a safe road of selenium supplementation for the human body.Oats is a widely grown in North China,which has a high nutritional and economic value.With the way of mxing soil with Na₂Se0₃,this article studied the effect of different Selenium concentrations in soil on the content of Selenium in the oat.The results indicated that:1.The concentration of 10-250 mg/kg applied by soil selenium fertilizer,oats growth and development;the concentration of selenium was 10-80 mg/kg,can get Se-rich oat and yield was5022 kg/hm²-5762 kg/hm²,Yield increasing rate was 2.5%-18.32%,;selenium can significantly increase the content of crude protein in oat,increase 1.3-1.6 times;at the same time,reduce the content of crude fiber,reducing 2%-4.1%;The concentration of 40mg/kg was the best application of selenium.2.To develop a method for determination of selenium in health products by microwave digestion-graphite furnace atomic absorption spectrometry?GFASS?Methods;9 ml HNO₃₊1 ml H₂O₂ was determine as the best digestion system.The recovery of Se was between 99.6%-103%,relative standard deviation was 1.65%,the detection limit was 0.49?g/L.Selenium in filling stage of oat was 157.04-585.54?g/kg,increased 10.41-39.01 times;the selenium enriched mature oat was 290.64-600.71?g/kg,increased 19.36-40.04 times.3.Using water,ethanol,0.1moL·L^-1NaCl,0.1moL·L^-1NaOH,0.05 moL·L^-1Tris-HCl,moL·L^-1HCL,reagent extraction agent on the different forms of selenium in plant samples were extracted.The results show that:in the sample protein bound selenium content at least state,th existence of selenium mainly are easy to combine with protein to form.About 35%of total selenium was Alkali soluble selenium.4.Alkali soluble and acid isoelectric point precipitation method extracting oat protein,optimization of protein extraction process,the isoelectric point is about PH=4.2,the concentration of NaoH was 0.23mol/L,extraction temperature 45?,solid-liquid ratio was 23:1?mL:g?,the extraction time is 8.4h,the best to get the rate of oat protein 70.17%,which accounted for 41%of the total Selenoprotein.5.To establish a HPLC-LC-MS method for determination of selenomethionine,the mobile phase is 70%acetonitrile+30%ultra pure water?containing 1%formic acid?,the flow rate was0.1ml/min,nebulizer pressure is 300PSI,capillary voltage is 80V,the collision energy of 30,to determine the ion track 198-109,The content of Se-met was 1.2?g/l.