Accumulation and species distribution of selenium in Se-enri

FoodChemistry115(2009)

727–734

ContentslistsavailableatScienceDirect

FoodChemistry

journalhomepage:http://doc.guandang.net/loc

ate/foodchem

AnalyticalMethods

AccumulationandspeciesdistributionofseleniuminSe-enrichedbacterialcellsoftheBi dobacteriumanimalis01

BowenZhanga,KangZhoua,JinlanZhanga,QianChena,GuorongLiua,NanShanga,WeiQina,PinglanLia,*,FengxiangLinb

ab

CollegeofFoodScienceandNutritionalEngineering,ChinaAgriculturalUniversity,17#QinghuaEastRoad,Beijing100083,ChinaHaerbingMeihuaShengwuTechnologyCo.,Ltd.,8-8#ShanghaiRoad,Heilongjiang150018,China

articleinfoabstract

Bi dobacteriumanimalis01(B.animalis01)couldabsorb16.7–39.6%ofinorganicseleniuminthemediumandtransformmostofitintoorganicselenium.Mostoftheorganicselenium(50.7–63.0%)wasfoundintheproteinfraction,9.62–18.7%inthepolysaccharidefraction,0.273–0.754%inthenucleicacidfraction,and20.8–30.9%inothercomponents.Furthermore,theseleniumcontentofdifferentproteinextractionswasinthefollowingorder:Alkaline-solubleprotein-boundSe(46.5–53.4%)>Water-solubleprotein-boundSe(27.4–30.8%)>Salt-solubleprotein-boundSe(7.79–11.9%)>Alcohol-solubleprotein-boundSe(notdetected).Additionally,themolecularmassofmostproteinsorproteinsubunitscontainingsele-niumwasabout10–20kDa.AnalysisbyLC–MSshowedthatselenomethionine(SeMet)isthemajorsele-nocompoundinprotein.

Ó2008ElsevierLtd.Allrightsreserved.

Articlehistory:

Received12May2008

Receivedinrevisedform5November2008Accepted2December2008

Keywords:Bi dobacteriaSelenium

Accumulation

SpeciesdistributionSelenomethionineLC–MS

1.Introduction

Selenium(Se),anessentialmicronutrientwithantioxidantproperties,hasreceivedconsiderableattentionforpotentialrolesincancerpreventionforbothhumanbeingsandanimals(Berry,2005).However,itwasregardedasatoxicelementbefore1973(Dubois&Belleville,1988).Evidencesindicatedthatthereisanar-rowgapbetweentoxicandessentiallevelsofSeinhumanbeings(Suhajda,Hegoczki,Janzso,Pais,&Vereczkey,2000).Thus,thereisaspecialemphasisonseleniuminrelationtodiseaseandavarietyofdegenerationdiseases,suchasKeshan,Kashin-Beck,andcancer(Tanetal.,2002).Moreover,severeseleniumde ciencyoccursinsomeremoteareaswherepeopleeatprimarilyplant-derivedfoodsgrownlocallyinselenium-de cientsoil,especiallyinsomeregionsofChina(Burk,2000).Itisthereforesuggestedto ndpropersourcesofdietaryseleniumsupplement.SomeauthorssuggestthatorganicSeisanidealadditivebecauseanimalsandhumansabsorbandretainitmorethaninorganicSe.Themainsourceofor-Abbreviation:Se,selenium;LC,liquidchromatography;MS,massspectrometry;SeMet,selenomethionine;Se-(Cys)2,selenocystine;MRM,multiplereactionsmonitoring.

*Correspondingauthor.Tel.:+861062737664.

E-mailaddresses:zbw-001@http://doc.guandang.net(B.Zhang),zkkingyy@http://doc.guandang.net(K.Zhou),yubawang@http://doc.guandang.net(J.Zhang),tranqian@http://doc.guandang.net(Q.Chen),lgr_22_2004@http://doc.guandang.net(G.Liu),qw618@http://doc.guandang.net(W.Qin),lipinglan420@http://doc.guandang.net(P.Li),linfx@http://doc.guandang.net(F.Lin).

0308-8146/$-seefrontmatterÓ2008ElsevierLtd.Allrightsreserved.doi:10.1016/j.foodchem.2008.12.006

ganicSeisseafoodand sh,whereasfoodslikecereals,meat,nuts,mushroomsandeggscanalsoincreasethedietaryseleniumintake(Muniz-Naveiroetal.,2005).Recently,moreresearchesshowedthatSe-enrichedyeastandsomeplantresourcessuchasSe-en-richedonion,garlic,fungiandteawereconsideredaseffectiveor-ganicseleniumsupplement(Dumont,Vanhaecke,&Cornelis,2006;Ip,Lisk,&Stoewsand,1992;Whanger,Ip,Polan,Uden,&Welbaum,2000).

Itisnoteworthythataswellasdiscussingfoodsasaseleniumsource,theimpactofseleniumonnutritionalbioavailabilityalsoshouldbediscussed(Kohrle,2004).Recentstudiesshowedthatseleniumwasfoundintheactivesiteofmanyselenoenzymesinwhichseleniumispresentasselenocysteine,includingglutathioneperoxidase,iodothyroninedeiodinase,andthioredixinreductase(Brigelius-Flohe,1999).Mostresearchersfoundseleniumcouldalsoformselenomethionine(SeMet)byreplacingsulphurinmethionineandcouldthenbeincorporatednonspeci callyintoproteinsinsteadofmethionine(Behne&Kyriakopoulos,2001).Inaddition,seleniumcanbeincorporatedintootherbiologicalmac-romolecules,suchasseleno-tRNA-sandselenosugar,in uencingthesynthesisofselenoproteins,respectively(Kobayashietal.,2002;Suzuki,Somekawa,&Suzuki,2006).

Severalseleniumsupplements,suchasBrazilnut,Se-enrichedyeastandSe-enrichedGanodermalucidum,hadalreadybeeninves-tigatedonSe-accumulation(totalseleniumcontent)andalsoonspeciesdistribution(Chunhiengetal.,2004;Chassaigne,Chery,

728B.Zhangetal./FoodChemistry115(2009)727–734

Bordin,&Rodriguez,2002;Zhaoetal.,2004;PonceDeLeon,Bayon,Paquin,&Caruso,2002).However,thereisnoinformationavail-ableonSe-enrichedBi dobacteriumfromthesetwoaspects.Bi do-bacteriumisoneofthemajorbacteriainhumanintestinal oraandiswellknownfortheirbene cialfunctionsonhealth,suchascon-trolofgastrointestinalinfections,stimulationoftheimmunesys-tem,anti-ulceractivity,anti-tumouractivityandantioxidativeeffects(Jack,Tagg,&Ray,1995;Picardetal.,2005).Therefore,itisofinteresttoknowwhetherbi dobacterumcouldalsobeusedasaneffectivecarrierforSeenrichment.Ifbi dobacterumcouldaccumulateinorganicseleniumfromculturemedium,Se-enrichedBi dobacteriumcouldbeexploredasadietarySesupplementsource.

TheobjectiveofthisstudyistoevaluatethecapabilityofBi do-bacterium.animalis01toaccumulationSeandtocharacterisethespeciesdistributionofseleniumintheSe-enrichedB.animalis01.Toaccomplishthisstudy,Se-enrichedsampleswere rstobtained,andthennucleicacid,polysaccharide,andproteinswereseparatedrespectively.Thecellproteinswerealsoseparatedonthebasisoftheiraf nityfordifferentsolvents.Thentheseleniumcontentwasanalysed.Finally,aliquidchromatographymethodwascou-pledtoelectrospraytandemmassspectrometry(LC–ESI–MS)tocon rmthepresenceofselenocystine(Se-(Cys)2)andselenomethi-onine(SeMet)inproteins.2.Mater …… 此处隐藏：33805字，全部文档内容请下载后查看。喜欢就下载吧 ……