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体外模拟消化（口腔、胃、小肠）：1、参考Gawlik-Dziki等（2009）方法（TheeffectofsimulateddigestioninvitroonbioactivityofwheatbreadwithTartarybuckwheatflavonesaddition）2.4.1.Preparationofsimulatedsaliva,gastricandintestinalfluidsSimulatedsalivasolutionwaspreparedbydissolveof2.38gNa2HPO4,0.19gKH2PO4and8gNaClin1lofdistilledwater.ThesolutionwasadjustedtopH6.75anda-amylase(EC3.2.1.1.)wasaddedtoobtain200Uofenzymeactivity.Forthegastricdigestion,0.32%pepsin(fromporcinestomachmucosa,pepsinA,EC3.4.23.1)dilutionin0.03MNaCl,pH1.2wasprepared.Simulatedintestinal.juicewaspreparedbydilutionof0.05gofpancreatinand0.3gofbileextractin35ml0.1MNaHCO3.2.4.1.Preparationofsimulatedsaliva,gastricandintestinalfluidsSimulatedsalivasolutionwaspreparedbydissolveof2.38gNa2HPO4,0.19gKH2PO4and8gNaClin1lofdistilledwater.ThesolutionwasadjustedtopH6.75andα-amylase(EC3.2.1.1.)wasaddedtoobtain200Uofenzymeactivity.Forthegastricdigestion,0.32%pepsin(fromporcinestomachmucosa,pepsinA,EC3.4.23.1)dilutionin0.03MNaCl,pH1.2wasprepared.Simulatedintestinaljuicewaspreparedbydilutionof0.05gofpancreatinand0.3gofbileextractin35ml0.1MNaHCO3.2、参考Versantvoort等（2005）（Applicabilityofaninvitrodigestionmodelinassessingthebioaccessibilityofmycotoxinsfromfood）和Hur等（2009）的方法（Influenceofinitialemulsifiertypeonmicrostructuralchangesoccurringinemulsifiedlipidsduringinvitrodigestion）Table1ConstituentsandconcentrationsofthevarioussyntheticjuicesoftheinvitrodigestionmodelrepresentingfedconditionsSaliva唾液Gastricjuice胃液Duodenaljuice十二指肠液Bilejuice胆汁Inorganicsolution10mlKCl89.6g/l15.7mlNaCl175.3g/l40mlNaCl175.3g/l30mlNaCl175.3g/l10mlKSCN20g/l3.0mlNaH2PO488.8g/l40mlNaHCO384.7g/l68.3mlNaHCO384.7g/l10mlNaH2PO488.8g/l9.2mlKCl89.6g/l10mlKH2PO48g/l4.2mlKCl89.6g/l10mlNaSO457g/l18mlCaCl2·2H2O22.2g/l6.3mlKCl89.6g/l150μlHCl37%g/g1.7mlNaCl175.3g/l10mlNH4Cl30.6g/l10mlMgCl25g/l20mlNaHCO384.7g/l6.5mlHCl37%g/g180μlHCl37%g/gOrganicsolution8mlurea25g/l10mlglucose65g/l4mlurea25g/l10mlurea25g/l10mlglucuronicacid(葡萄糖醛酸)2g/l3.4mlurea25g/l10mlglucosaminehydrochloride(盐酸氨基葡萄糖)33g/lAddtomixtureorganic+inorganicsolution290mgα-amylase1gBSA9mlCaCl2·2H2O22.2g/l10mlCaCl2·2H2O22.2g/l15mguricacid2.5gpepsin1gBSA1.8gBSA25mgmucin3gmucin9gpancreatin30gbile1.5glipasepH6.8±0.21.30±0.028.1±0.28.2±0.2Theinorganicandorganicsolutionsareaugmentedto500mlwithdistilledwater.Aftermixingoftheinorganicandorganicsolutions,somefurtherconstituentsareaddedanddissolved.Ifnecessary,thepHofthejuicesisadjustedtotheappropriateinterval.另外，抗性淀粉含量测定：1、参考Li等（2008）方法（Characterizationofmaizeamylose-extender(ae)mutantstarches.PartI:Relationshipbetweenresistantstarchcontentsandmolecularstructures）2.3.Resistantstarch(RS)contentRScontentsoftheae-mutantstarchsamplesweredeterminedusingtheAOACMethod991.43fortotaldietaryfiber(AOAC,2003)andEnglyst’smethod(1992)forcomparison.FortheAOAC991.43method,starch(1.0g,dry-starchbasis,dsb)wassuspendedinaMes-trisbuffersolution(0.05M,40ml)andhydrolyzedwith500uofa-amylasefromBacilluslicheniformis(SigmaChemical,Cat.No.A3403)inaboilingwater-bathfor30minwithstir.ThesamplewasthendigestedwithproteasefromBacilluslicheniformis(5mg,SigmaChemical,Cat.No.P3910)at60ºCinashakerwaterbathfor30min.ThesampledispersionwasadjustedtopH4.4–4.6byaddingHClandthenhydrolyzedwithamyloglucosidase(300U,Sigmachemical,Cat.No.A9913)at60ºCinashakerwater-bathfor30min.Thedigestedsamplewasfilteredthroughacelitelayerinacrucibleandwashedtwicewith15mlof78%ethanol,twicewith15mlof100%ethanolandrinsedwith15mlofacetone.Theremainingsamplewasdriedinanovenat100ºCovernight.Theresistantstarchcontentwascalculatedusingtheequation:（%）RScontent=Remainingsampleweight(g,dsb)/initialsampleweight(g,dsb)×100%ForRSdeterminedusingEnglyst’smethod(1992),Starch(1.000g,db)in20mLofsodiumacetatebuffer(0.1M,pH5.2)wascookedinaboilingwater-bathfor30min.Thestarchdispersionwascooleddownto37ºC,mixedwithanenzymesolution(5mL)consistingofpancreatinextractandamyloglucosidase,andincubatedinawater-bathat37ºC.Thepancreatinextractwaspreparedasfollows;3.0gofpancreatin(Sigma,Cat.No.P7545)wassuspendedin20mLdeionizedwater,stirredfor10minatroomtemperature,andcentrifugedat1500gfor10min.Theenzymesolutionwaspreparedbymixing13.5mlsupernatantofpancreatinextract,210Uamyloglucosidase(Sigma,Cat.No.A7095),and1.0mLdeionizedwater.Therapiddigestiblestarch(RDS)wasdefinedasthetotalstarchdigestedwithinthefirst20min,andtheslowlydigestiblestarch(SDS)wasthestarchdigestedbetween20and120min(Englystetal.,1992).Theresistantstarchcontentwascalculatedasfollows:（%）RScontent=100%×(totalstarch–RDS-SDS)(g,dsb)/totalstarch(g,dsb)