采用高效液相色谱-电喷雾串联质谱定量测量西兰花、豆芽、甘蓝芽的硫代葡萄糖苷含量

采用高效液相色谱电喷雾串联质谱定量测量西兰花、豆芽、甘蓝芽的硫代葡萄糖苷含量ANALYTICALBIOCHEMISTRYANALYTICALBIOCHEMISTRY34320059399WWWELSEVIERCOM/LOCATE/YABIOQUANTITATIVEDETERMINATIONOFINTACTGLUCOSINOLATESINBROCCOLI,BROCCOLISPROUTS,BRUSSELSSPROUTS,ANDCAULIOWERBYHIGHPERFORMANCELIQUIDCHROMATOGRAPHYELECTROSPRAYIONIZATIONTANDEMMASSSPECTROMETRYQINGGUOTIAN,ROBINAROSSELOT,STEVENJSCHWARTZDEPARTMENTOFFOODSCIENCEANDTECHNOLOGY,THEOHIOSTATEUNIVERSITY,COLUMBUS,OH432101007,USARECEIVED25FEBRUARY2005AVAILABLEONLINE23MAY2005ABSTRACTMANYMETHODSHAVEBEENPROPOSEDTOANALYZEGLUCOSINOLATES,ACLASSOFPHYTOCHEMICALSWHOSEBREAKDOWNPRODUCTSARETHOUGHTTOBERESPONSIBLEFORANIMPROVEMENTINHEALTHHOWEVER,FEWAREQUANTITATIVEANDMANYARETIMECONSUMINGASELECTIVEANDSENSITIVEQUANTITATIVEMETHODFORDIRECTDETERMINATIONOFINTACTGLUCOSINOLATESWASDEVELOPEDUSINGLIQUIDCHROMATOGRAPHYCOUPLEDTOELECTROSPRAYIONIZATIONTANDEMMASSSPECTROMETRYWITHSELECTEDREACTIONMONITORINGDETECTIONDETECTIONLIMITSFORGLUCOIBERIN,SINIGRIN,PROGOITRIN,GLUCOERUCIN,ANDGLUCOTROPAEOLINWERE175,138,136,06,AND063PMOL,RESPECTIVELYINTRAASSAYPRECISIONOFTHEMETHODWASWITHIN10FOREACHCOMPOUNDTHEMETHODWASSUCCESSFULLYAPPLIEDTOQUANTIFY10INDIVIDUALGLUCOSINOLATESINBROCCOLI,BROCCOLISPROUTS,BRUSSELSSPROUTS,ANDCAULIOWERTHEADVANTAGEOFTHEPROPOSEDMETHODINCLUDESANALYSISOFINDIVIDUALINTACTGLUCOSINOLATESRATHERTHANTHECONVERSIONTODESULFOGLUCOSINOLATES,ANINCREASEDSELECTIVITYTHROUGHTHEUSEOFMASSSPECTROMETRY,ANDA10FOLDIMPROVEMENTINDETECTIONSENSENSITIVITYOVERCONVENTIONALLYUSEDHPLCTECHNIQUES2005ELSEVIERINCALLRIGHTSRESERVEDKEYWORDSGLUCOSINOLATESCRUCIFEROUSVEGETABLESBRASSICASPPLCESI/MS/MSGLUCOSINOLATESBTHIOGLUCOSIDENHYDROXYSULFATESAREAUNIQUEGROUPOFSULFURCONTAININGPLANTSECONDARYMETABOLITESFOUNDINCRUCIFEROUSVEGETABLESSUCHASBROCCOLI,BRUSSELSSPROUTS,CAULIOWER,ANDKALEASSHOWNINTABLE1,ALLGLUCOSINOLATESCONTAINABDGLUCOPYRANOSEMOIETYLINKEDTOASULFURATOMANDEITHERANALIPHATIC,AROMATIC,ORINDOLESIDECHAIN1MORETHAN120TYPESOFGLUCOSINOLATESWITHVARYINGSIDECHAINSHAVEBEENISOLATEDFROMNATURE,BUTNOTALLAREPRESENTINEDIBLEPLANTS2EPIDEMIOLOGICALSTUDIESHAVESHOWNTHATADIETRICHINFRUITSANDVEGETABLESSUCHASCRUCIFEROUSVEGETABLESMAYREDUCETHERISKOFMANYTYPESOFCANCERS3,4INARECENTCORRESPONDINGAUTHORFAX16142924233EMAILADDRESSSCHWARTZ177OSUEDUSJSCHWARTZEPIDEMIOLOGICALSTUDYINVESTIGATINGTHERELATIONSHIPBETWEENBLADDERCANCERINCIDENCEANDTOTALFRUITANDVEGETABLEINTAKE,NORELATIONSHIPWASFOUNDBETWEENBLADDERCANCERANDTOTALFRUIT,TOTALFRUITANDVEGETABLE,GREENLEAFYVEGETABLE,ORYELLOWVEGETABLEINTAKE5HOWEVER,ANINVERSERELATIONSHIPWASFOUNDBETWEENBLADDERCANCERRISKANDCRUCIFEROUSVEGETABLEINTAKEISOTHIOCYANATESANDINDOLES,THEBREAKDOWNPRODUCTSOFGLUCOSINOLATES,AREBELIEVEDTOBETHEPRIMARYCONTRIBUTORSOFCRUCIFEROUSVEGETABLESCHEMOPREVENTIVEEECTSVIAAVARIETYOFMECHANISMS68HOWEVER,THESECOMPOUNDSAREFOUNDINPLANTSMAINLYINTHEIRCORRESPONDINGGLUCOSINOLATEPRECURSORFORMSTHEYAREBROKENDOWNTHROUGHTHEENDOGENOUSENZYMEMYROSINASEDURINGDIGESTIONORWHENTHEPLANTSCELLSTRUCTUREISDISRUPTED,SUCHASDURINGCHOPPINGANDCHEWING00032697/SEEFRONTMATTER2005ELSEVIERINCALLRIGHTSRESERVEDDOI101016/JAB20050404594QUANTITATIONOFGLUCOSINOLATESINCRUCIFEROUSVEGETABLES/QTIANETAL/ANALBIOCHEM34320059399TABLE1STRUCTURESOFGLUCOSINOLATESBASICSTRUCTURESTRUCTUREOFRH2CCHACH2AH2CCHACH22ACHEMICALNAME2PROPENYLGLUCOSINOLATEBUT3ENYLGLUCOSINOLATE2HYDROXYBUT3ENYLGLUCOSINOLATEH3CASACH24AH3CASOACH23AH3CASOACH24AH3CASOACH25A4METHYLTHIOBUTYLGLUCOSINOLATE3METHYLSULNYLPROPYLGLUCOSINOLATE4METHYLSULNYLBUTYLGLUCOSINOLATE5METHYLSULNYLPENTYLGLUCOSINOLATEBENZYLGLUCOSINOLATETRIVIALNAMESINIGRINGLUCONAPINPROGOITRINGLUCOERUCINGLUCOIBERINGLUCORAPHANINGLUCOALYSSINGLUCOTROPAEOLININDOL3YLMETHYLGLUCOSINOLATEGLUCOBRASSICIN1METHOXYINDOL3YLMETHYLGLUCOSINOLATENEOGLUCOBRASSICIN4METHOXYINDOL3YLMETHYLGLUCOSINOLATE4METHOXYGLUCOBRASSICINITISESTIMATEDTHATTHEAVERAGEDAILYGLUCOSINOLATEINTAKERANGESFROM16TO112MGPERPERSONINCANADA,UNITEDKINGDOM,ANDJAPAN911THEREISANINCREASINGINTERESTINGLUCOSINOLATEANALYSISBECAUSEOFTHEPOSSIBLEPROTECTIVEANDCHEMOPREVENTIVEEECTSOFGLUCOSINOLATESAGAINSTCHEMICALCARCINOGENSSEVERALMETHODOLOGIESHAVEPREVIOUSLYBEENDEVELOPEDTOQUANTIFYTOTALANDINDIVIDUALGLUCOSINOLATESINPLANTS,SUCHASMEASUREMENTOFTHEGLUCOSINOLATESENZYMATICBREAKDOWNPRODUCTS,DESULFATEDGLUCOSINOLATES,ANDINTACTGLUCOSINOLATES12,13HOWEVER,RARELYDOESAMETHODPROVIDERAPIDITY,SIMPLICITY,SENSITIVITY,ANDACCURACYTODISCRIMINATEAMONGALLCOMPOUNDSOFINTEREST1MASSSPECTROMETRYHASBECOMEAPOWERFULTECHNIQUEFORQUANTICATIONOFBIOACTIVECOMPOUNDSINCOMPLEXBIOLOGICALMATRICESWITHHIGHSELECTIVITYANDSENSITIVITY1416HOWEVER,MOSTPREVIOUSLYPUBLISHEDMETHODSOFMASSSPECTROMETRICANALYSISOFGLUCOSINOLATESWEREQUALITATIVE1719RECENTLY,GRITHSETAL20REPORTEDALIQUIDCHROMATOGRAPHYATMOSPHERICPRESSURECHEMICALIONIZATIONMASSSPECTROMETRICLCAPCI1/MSMETHODFORDETERMINATIONOFDESULFOGLUCOSINOLATES,ABBREVIATIONSUSEDAPCI,ATMOSPHERICPRESSURECHEMICALIONIZATIONESI,ELECTROSPRAYIONIZATIONSRM,SELECTEDREACTIONMONITORINGLLOQ,LOWERLIMITOFQUANTICATIONFW,FRESHWEIGHTMDL,METHODDETECTIONLIMITULOQ,UPPERLIMITOFQUANTICATION1REQUIRING18HFORTHEPREPARATIONOFDESULFOGLUCOSINOLATESAFTEREXTRACTIONINTHISPAPER,WEREPORTARAPIDQUANTITATIVEMETHODFORDIRECTDETERMINAT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