Selenium is one of the important trace elements in the human body.Its deficiency will directly affect human health.With people's attention to health,the content of selenium in food has gradually attracted attentio...Selenium is one of the important trace elements in the human body.Its deficiency will directly affect human health.With people's attention to health,the content of selenium in food has gradually attracted attention.However,detecting selenium compounds in complex samples remains a challenge.In this work,we built an online heating-reaction device.This device combines the electrospray extraction ionization mass spectrometry(EESI-MS)with the heating reaction device,which can simultaneously detect various selenium compounds in complex liquid samples.Under acidic conditions,the sample was heated and catalyzed by a heating reaction device,so that the SeO~(2-)_(3)and O-phenylenediamine(OPD)could generate 1,3-dihydro-2,1,3-benzoselenadiazole.Based on the above reactions,we can detect organic selenium,inorganic selenium and other compounds in liquid samples by organic mass spectrometry.In this experiment,we determined the content of three forms of selenium:selenomethionine(SeMet),l-selenocystine(SeCys(2)),and sodium selenite.The calibration curves for SeMet,SeCys(2),and sodium selenite showed strong linearity within a range of 0.50-50.00μg/L.The limits of detection(LOD)for the three compounds were 0.22,0.27,and 0.41μg/L,respectively.The limits of quantification(LOQ)were 0.68,0.81,and 1.23μg/L,respectively.Spiked recoveries at three levels ranged from 98.8%to 106.1%.In addition,this method can simultaneously detect three selenium compounds and three other specific chemical components in tea infusion samples,providing a rapid and efficient method for identifying tea quality.展开更多
Selemum (Se) and many of its compounds are among the most toxic of nutrients. Selenium toxicity was first described in range animals in the western United States in the 1930's which consumed' selenium accumula...Selemum (Se) and many of its compounds are among the most toxic of nutrients. Selenium toxicity was first described in range animals in the western United States in the 1930's which consumed' selenium accumulator' plants of the genus Astragalus, Xylorrhiza,Oonopsis, and Stanleya. Selenites and selenates from the soil accumulate in these plants primarily as methylated selenium compounds and plants evolve dimethyldiselenide and dimethyselenide.Dietary selenium, primarily as selenomethionine and selenocysteine for humans fulfill the dietary requirement for selenoenzymes and proteins. In humans and animals excessive dietary selenium may be toxic. In vitro, selenium compounds such as selenite, selenium dioxide and diselenides react with thiols, such as glutathione, producing superoxide and other reactive oxygen species. This catalytic reaction of selenium compounds with thiols likely accounts for selenium toxicity to cells ex vivo and in vivo where the major glutathione producing organ,the liver, is also the major target organ of selenium toxicity.Selenium enzymes and selenoethers that do not readily form a selenide (RSe-) anion and compounds such as Ebselen where selenium is sequestered, are not toxic. Methylation of selenium by both plants and animals serves to detoxify selenium by generating methylselenides. Alternatively, full reduction of Se to elemental selenium (Se0) as done by some bacteria and the formation of heavy metal selenides such as Ag2Se or Hg2Se, results in a non-catalytic nontoxic form of selenium.This catalytic prooxidant attribute of some selenium compounds appears to account for its toxicity when such activity exceeds plant and animal methylation reactions and antioxidant defenses. This prooxidant activity may also account for cellular apoptosis and may provide a useful pharmaceutical application for selenium compounds as antibacterial, antiviral, antifungal and anticancer agents展开更多
A novel selenium-containing compound,selenoneine,has been isolated as the major form of organic selenium in the blood and tissues of tuna.Selenoneine harbors a selenium atom in the imidazole ring,2-selenylNα,Nα,Nα-...A novel selenium-containing compound,selenoneine,has been isolated as the major form of organic selenium in the blood and tissues of tuna.Selenoneine harbors a selenium atom in the imidazole ring,2-selenylNα,Nα,Nα-trimethyl-L-histidine,and is a selenium analog of ergothioneine.This selenium compound has strong antioxidant capacity and binds to heme proteins,such as hemoglobin and myoglobin,to protect them from iron auto-oxidation,and it reacts with radicals and methylmercury(MeHg) .The organic cations/carnitine transporter OCTN1 transports selenoneine and MeHg,regulates Se-enhanced antioxidant activity,and decreases MeHg toxicity.Thus,the dietary intake of selenoneine,by consuming fish,might decrease the formation of reactive oxygen radicals that could oxidize nucleotides in DNA,and thereby inhibit carcinogenesis,chronic diseases,and aging.展开更多
Under microwave radiation conditions,a series of heterocyclic aromatic selenium compounds of 2,1,3-benzoselena-diazole(BS);1,2,5-selenadiazolo[3.4-b]pyridine(SPb);5-methy1-2,1,3-benzo-[3,4-c]selenadiazole(MB);5,7-dihy...Under microwave radiation conditions,a series of heterocyclic aromatic selenium compounds of 2,1,3-benzoselena-diazole(BS);1,2,5-selenadiazolo[3.4-b]pyridine(SPb);5-methy1-2,1,3-benzo-[3,4-c]selenadiazole(MB);5,7-dihydroxy-1,2,5-selenadiazolo-[3,4-d]pyrimi dine(DHSP)and 2,1,3-naphtho-[2,3-c]selenadiazole(NS) were synthesized with their respective ortho-aromatic diamines and selenium dioxide,and their yields were between 29% and 84%.The products obtained from the microwave solid-state reactions were characterized by IR,XRD,UV,FS and EA.展开更多
基金financially supported by Jiangxi University of Chinese Medicine School-level Science and Technology Innovation Team Development Program(No.CXTD22005)PhD research startup fund of Jiangxi University of Chinese Medicine(No.2023BSZR005)。
文摘Selenium is one of the important trace elements in the human body.Its deficiency will directly affect human health.With people's attention to health,the content of selenium in food has gradually attracted attention.However,detecting selenium compounds in complex samples remains a challenge.In this work,we built an online heating-reaction device.This device combines the electrospray extraction ionization mass spectrometry(EESI-MS)with the heating reaction device,which can simultaneously detect various selenium compounds in complex liquid samples.Under acidic conditions,the sample was heated and catalyzed by a heating reaction device,so that the SeO~(2-)_(3)and O-phenylenediamine(OPD)could generate 1,3-dihydro-2,1,3-benzoselenadiazole.Based on the above reactions,we can detect organic selenium,inorganic selenium and other compounds in liquid samples by organic mass spectrometry.In this experiment,we determined the content of three forms of selenium:selenomethionine(SeMet),l-selenocystine(SeCys(2)),and sodium selenite.The calibration curves for SeMet,SeCys(2),and sodium selenite showed strong linearity within a range of 0.50-50.00μg/L.The limits of detection(LOD)for the three compounds were 0.22,0.27,and 0.41μg/L,respectively.The limits of quantification(LOQ)were 0.68,0.81,and 1.23μg/L,respectively.Spiked recoveries at three levels ranged from 98.8%to 106.1%.In addition,this method can simultaneously detect three selenium compounds and three other specific chemical components in tea infusion samples,providing a rapid and efficient method for identifying tea quality.
文摘Selemum (Se) and many of its compounds are among the most toxic of nutrients. Selenium toxicity was first described in range animals in the western United States in the 1930's which consumed' selenium accumulator' plants of the genus Astragalus, Xylorrhiza,Oonopsis, and Stanleya. Selenites and selenates from the soil accumulate in these plants primarily as methylated selenium compounds and plants evolve dimethyldiselenide and dimethyselenide.Dietary selenium, primarily as selenomethionine and selenocysteine for humans fulfill the dietary requirement for selenoenzymes and proteins. In humans and animals excessive dietary selenium may be toxic. In vitro, selenium compounds such as selenite, selenium dioxide and diselenides react with thiols, such as glutathione, producing superoxide and other reactive oxygen species. This catalytic reaction of selenium compounds with thiols likely accounts for selenium toxicity to cells ex vivo and in vivo where the major glutathione producing organ,the liver, is also the major target organ of selenium toxicity.Selenium enzymes and selenoethers that do not readily form a selenide (RSe-) anion and compounds such as Ebselen where selenium is sequestered, are not toxic. Methylation of selenium by both plants and animals serves to detoxify selenium by generating methylselenides. Alternatively, full reduction of Se to elemental selenium (Se0) as done by some bacteria and the formation of heavy metal selenides such as Ag2Se or Hg2Se, results in a non-catalytic nontoxic form of selenium.This catalytic prooxidant attribute of some selenium compounds appears to account for its toxicity when such activity exceeds plant and animal methylation reactions and antioxidant defenses. This prooxidant activity may also account for cellular apoptosis and may provide a useful pharmaceutical application for selenium compounds as antibacterial, antiviral, antifungal and anticancer agents
基金Supported by In part grants from the Ministry of Agriculture,Forestry,and Fisheries of Japan(Rural Biomass Research Project,BM-D2300)and Fisheries Research Agency
文摘A novel selenium-containing compound,selenoneine,has been isolated as the major form of organic selenium in the blood and tissues of tuna.Selenoneine harbors a selenium atom in the imidazole ring,2-selenylNα,Nα,Nα-trimethyl-L-histidine,and is a selenium analog of ergothioneine.This selenium compound has strong antioxidant capacity and binds to heme proteins,such as hemoglobin and myoglobin,to protect them from iron auto-oxidation,and it reacts with radicals and methylmercury(MeHg) .The organic cations/carnitine transporter OCTN1 transports selenoneine and MeHg,regulates Se-enhanced antioxidant activity,and decreases MeHg toxicity.Thus,the dietary intake of selenoneine,by consuming fish,might decrease the formation of reactive oxygen radicals that could oxidize nucleotides in DNA,and thereby inhibit carcinogenesis,chronic diseases,and aging.
文摘Under microwave radiation conditions,a series of heterocyclic aromatic selenium compounds of 2,1,3-benzoselena-diazole(BS);1,2,5-selenadiazolo[3.4-b]pyridine(SPb);5-methy1-2,1,3-benzo-[3,4-c]selenadiazole(MB);5,7-dihydroxy-1,2,5-selenadiazolo-[3,4-d]pyrimi dine(DHSP)and 2,1,3-naphtho-[2,3-c]selenadiazole(NS) were synthesized with their respective ortho-aromatic diamines and selenium dioxide,and their yields were between 29% and 84%.The products obtained from the microwave solid-state reactions were characterized by IR,XRD,UV,FS and EA.
