HighpurityAmyloglucosidase(Aspergillusniger)foruseinresearch,biochemicalenzymeassaysandinvitrodiagnosticanalysis.EC3.2.1.3CAZyFamily:GH15CAS:9032-08-0glucan1,4-alpha-glucosidase;4-alpha-D-glucanglucohydrolase FromA.niger.Highpurity. Electrophoreticallyhomogeneous.StABIlisedliquidin50%(v/v)glycerol.Forusein MegazymeTotalStarchandDietaryFiber methods.E-AMGDF-A-100MLspecificallytobeusedwithANKOMTDFDietaryFiberAnalyzer.Specificactivity:~36 U/mg(40oC,pH4.5onsolublestarch);~200U/mL(40oC,pH4.5,p-nitrophenylβ-maltoside);~3,260U/mL(40oC,pH4.5,solublestarch).Stability:>4yearsat4oC.DatabookletsforeachpacksizearelocatedintheDocumentationtab.ViewMegazyme’slatestGuideforDietaryFiberAnalysis.Hydrolysisofα-D-glucansandα-D-gluco-oligosaccharidesbycladosporiumresinaeglucoamylases.McCleary,B.V.&Anderson,M.A.(1980).CarbohydrateResearch,86(1),77-96.LinktoArticleReadAbstractCulturefiltratesofCladosporiumresinaeATCC20495containamixtureofenzymesabletoconvertstarchandpullulanefficientlyintoD-glucose.Cultureconditionsforoptimalproductionofthepullulan-degrADIngactivityhavebeenestablished.Theamylolyticenzymepreparationwasfractionatedbyion-exchangeandmolecular-sievechromatography,andshowntocontainα-D-glucosidase,α-amylase,andtwoglucoamylases.Theglucoamylaseshavebeenpurifiedtohomogeneityandtheirsubstratespecificitiesinvestigated.Oneoftheglucoamylases(termedP)readilyhydrolysesthe(1→6)-α-Dlinkagesinpullulan,amylopectin,isomaltose,panose,and63-α-D-glucosylmaltotriose.Eachoftheglucoamylasescleavesthe(1→6)-α-Dlinkageinpanosemuchmorereadilythanthatinisomaltose.Measurementofdietaryfibrecomponents:theimportanceofenzymepurity,activityandspecificity.McCleary,B.V.(2001),“AdvancedDietaryFibreTechnology”,(B.V.McClearyandL.Prosky,Eds.),BlackwellScience,Oxford,U.K.,pp.89-105.LinktoArticleReadAbstractInterestindietaryfibreisundergoingadramaticrevival,thanksinparttotheintroductionofnewcarbohydratesasdietaryfibrecomponents.Muchemphasisisbeingplacedondetermininghowmuchfibreispresentinafood.Linkingaparticularamountoffibretoaspecifichealthbenefitisnowanimportantareaofresearch.Theterm"dietaryfibre"firstappearedin1953,andreferredtohemicelluloses,cellulosesandlignin(Theandere/tf/.1995).Trowell(1974)recommendedthistermasareplacementforthenolongeracceptableterm"crudefibre".Burkitt(1995)haslikenedtheinterestindietaryfibretothegrowthofariverfromitsfirsttrickletoamightytorrentHeobservesthatdietaryfibre"wasfirstviewedasmerelythelessdigestIBLeconstituentoffoodwhichexertsalaxativeactionbyirritatingthegut",thusacquiringthedesignation"roughage"-atermlaterreplacedby"crudefibre"andultimatelyby"dietaryfibre".Variousdefinitionsofdietaryfibrehaveappearedovertheyears,partlyduetothevariousconceptsusedinderivingtheterm(i.e.originofmaterial,resistancetodigestion,fermentationinthecolon,etc.),andpartlytothedifficultiesassociatedwithitsmeasurementandlabelling(Mongeauetal.1999).Theprincipalcomponentsofdietaryfibre,astraditionallyunderstood,arenon-starchpolysaccharides(whichinplantfibreareprincipallyhemicellulosesandcelluloses),andthenon-carbohydratephenoliccomponents,cutin,suberinandwaxes,withwhichtheyareassociatedinnature.In1976,thedefinitionofdietaryfibrewasmodifiedtoincludegumsandsomepecticsubstances,basedontheresistancetodigestionofthesecomponentsintheupperintestinaltract.Forthepurposesoflabelling,Englystetal.(1987)proposedthatdietaryfibrebedefinedas"non-starchpolysaccharides(NSP)inthedietthatarenotdigestedbytheendogenoussecretionsofthehumandigestivetract".MethodswereconcurrentlydevelopedtospecificallymeasureNSP(Englystetal.1994).Dietaryfiberandavailablecarbohydrates.McCleary,B.V.&Rossiter,P.C.(2007).“DietaryFiber:AnInternationalPerspectiveforHarmonizationofHealthBenefitsandEnergyValues”,(DennisT.GordonandToshinaoGoda,Eds.),AACCInternational,Inc.,pp.31-59.LinktoArticleReadAbstractDebatecontinuesonthedefinitionofdietaryfiber(DF),methodsformeasurementofDF,andmethodsformeasurementofthecarbohydratesthatarereadilyhydrolyzedandabsorbedinthehumansmallintestine.HenNEBergandStahmanndevelopedthe"Wende"proximatesystemforanalysisoffoodsin1860,andasetofvaluesobtainedusingthismethodwerepublishedbyAtwaterandBryantin1900.ThismethodisstillinuseintheUSAforthemeasurementoftotalcarbohydrate.Inthisprocedure,totalcarbohydrateismeasuredbydifferenceafterdeductingthemoisture,protein,fatandashfromthetotalweight.Carbohydratecalculatedinthiswaycontainsnotonlysugarandstarch,butalsothe"unavailablecarbohydrate"ofDF.However,thereareanumberofproblemswiththisapproach,asthe"bydifference"figureincludesanumberofnon-carbohydratecomponentssuchaslignin,organicacids,tannins,waxesandsomeMaillardproducts.Inadditiontothiserror,itcombinesalloftheanalyticalerrorsfromtheotheranalyses(FAO1997).AneedforinformationonthecarbohydratecompositionoffoodsfordiabeticspromptedMcCanceandLawrence(1929)toattempttomeasurecarbohydratecompositiontogainresultsthatwouldbeofBIOLOGicalsignificance.Theydividedthecarbohydratesinfoodsintotwobroadgroups,"available"and"unavailable".Theavailablecarbohydrates,thatis,sugarplusstarch,weredefinedasthosethataredigestedandabsorbedbymanandareglucogenic.Theunavailablecarbohydratesweredefinedasthosethatarenotdigestedbytheendogenoussecretionsofthehumandigestivetract.Inthemid1920s,McCanceobtainedagrantof£30peryearfromtheMedicalResearchCounciltoanalyserawandcookedfruitsandvegetablesfortotal"availablecarbohydrate";valuesneededforcalculatingdiabeticdiets.MeasurementofamyloglucosidaseusingP-nitrophenylβ-maltosideassubstrate.McCleary,B.V.,Bouhet,F.&Driguez,H.(1991).BiotechnologyTechniques,5(4),255-258.LinktoArticleReadAbstractAnenzyme-linkedassayforthemeasurementofamyloglucosidaseincommercialenzymemixturesandcrudeculturefiltratesisdescribed.Amethodforthesynthesisofthesubstrateemployed,p-nitrophenylβ-D-maltoside,isalsodescribed.Thesubstrateisusedinthepresenceofsaturatinglevelsofβ-glucosidase.WitharangeofAspergillussp.culturefiltrates,anexcellentcorrelationwasfoundforvaluesobtainedwiththisassayandaconventionalassayemployingmaltoseassubstratewithmeasurementofreleasedglucose.Measuringdietaryfibre.McCleary,B.V.(1999).TheWorldofIngredients,50-53.LinktoArticleReadAbstractInterestindietaryfibreisundergoingadramaticrevivalthanksinparttotheintroductionofnewcarbohydratesasdietaryfibrecomponents.Muchemphasisisbeingplacedondetermininghowmuchfibreispresentinafood.Linkingaparticularamountoffibretoaspecifichealthbenefitisnowanimportantareaofresearch.TotalDietaryFibre.Theterm“dietaryfibre”firstappearedin1953andreferredtohemicelluloses,cellulosesandlignin(1).In1974,Trowell(2)recommendedthistermasareplacementforthenolongeracceptableterm“crudefibre”Burkitt(3)haslikenedtheinterestindietaryfibretothegrowthofariverfromitsfirsttrickletoamightytorrent.Heobservesthatdietaryfibre“wasviewedasmerelythelessdigestibleconstituentoffoodwhichexertsalaxativeactionbyirritatingthegut“thusacquiringthedesignation“roughage”atermwhichwaslaterreplacedby“crudefibre”andultimatelyby“dietaryfibre”Variousdefinitionsofdietaryfibrehaveappearedovertheyears,partlyduethevariousconceptsusedinderivingtheterm(i.e.originofmaterial,resistancetodigestion,fermentationinthecolonetc.),andpartlytothedifficultiesassociatedwithitsmeasurementandlabelling(4).Theprinciplecomponentsofdietaryfibre,astraditionallyunderstood,arenon-starchpolysaccharides,whichinplantfibreareprincipallyhemicellulosesandcelluloses,andthenon-carbohydratephenoliccomponents,cutin,suberinandwaxeswithwhichtheyareassociatedinNature.Enzymepurityandactivityinfibredeterminations.McCleary,B.V.(1999).CerealFoodsWorld,44(8),590-596.LinktoArticleReadAbstractDietaryfiberismainlycomposedofplantcellwallpolysaccharidessuchascellulose,hemicellulose,andpecticsubstances,butitalsoincludesligninandotherminorcomponents(1).Basically,itcoversthepolysaccharidesthatarenothydrolyzedbytheendogenoussecretionsofthehumandigestivetract(2,3).Thisdefinitionhasservedasthetargetforthosedevelopinganalyticalproceduresforthemeasurementofdietaryfiberforqualitycontrolandregulatoryconsiderations(4).Mostproceduresforthemeasurementoftotaldietaryfiber(TDF),orspecificpolysaccharidecomponents,eitherinvolvesomeenzymetreatmentstepsoraremainlyenzyme-based.InthedevelopmentofTDFproceduressuchastheProskymethod(AOACInternational985.29,AACC32—05)(5),theUppsalamethod(AACC32-25)(6),andtheEnglystmethod(7),theaimwastoremovestarchandproteinthroughenzymetreatment,andtomeasuretheresidueasdietaryfiber(afterallowingforresidual,undigestedproteinandash).Dietaryfiberwasmeasuredeithergravimetricallyorbychemicalorinstrumentalprocedures.Manyoftheenzymetreatmentstepsineachofthemethods,particularlytheprosky(5)andtheUppsala(6)methodsareverysimilar.Asanewrangeofcarbohydratesisbeingintroducedaspotentialdietaryfibercomponents,theoriginalassayprocedureswillneedtobereexamined,andinsomecasesslightlymodified,toensureaccurateandquantitativemeasurementofthesecomponentsandofTDF.These“new”dietaryfibercomponentsincluderesistantnondigestibleoligosaccharides;nativeandchemicallymodifiedpolysaccharidesofplantandalgalorigin(galactomannan,chemicallymodifiedcelluloses,andagarsandcarrageenans);andresistantstarch.Tomeasurethesecomponentsaccurately,thepurity,activity,andspecificityoftheenzymesemployedwillbecomemuchmoreimportant.Aparticularexampleofthisisthemesurementoffructan.Thiscarbohydrateconsistsofafractionwithahighdegreeofpolymerization(DP)thatisprecipitatedinthestandardProskymethod(5,8)andalowDPfractionconsequentlyisnotmeasured(9).Resistantstarchposesaparticularproblem.Thiscomponentisonlypartiallyresistanttodegradationbyα-amylase,sothelevelofenzymeusedandtheincubationconditions(timeandtemperature)arecritical.Importanceofenzymepurityandactivityinthemeasurementoftotaldietaryfibreanddietaryfibrecomponents.McCleary,B.V.(2000).JournalofAOACInternational,83(4),997-1005.LinktoArticleReadAbstractAstudywasmadeoftheeffectoftheactivityandpurityofenzymesintheassayoftotaldietaryfiber(AOACMethod985.29)andspecificdietaryfibercomponents:resistantstarch,fructan,andβ-glucan.Inthemeasurementoftotaldietaryfibercontentofresistantstarchsamples,theconcentrationofα-amylaseiscritical;however,variationsinthelevelofamyloglucosidasehavelittleeffect.Contaminationofamyloglucosidasepreparationswithcellulasecanresultinsignificantunderestimationofdietaryfibervaluesforsamplescontainingβ-glucan.Pureβ-glucanandcellulasepurifiedfromAspergillusnigeramyloglucosidasepreparationswereusedtodetermineacceptablecriticallevelsofcontamination.Sucrose,whichinterfereswiththemeasurementofinulinandfructooligosaccharidesinplantmaterialsandfoodproducts,mustberemovedbyhydrolysisofthesucrosetoglucoseandfructosewithaspecificenzyme(sucrase)followedbyborohydridereductionofthefreesugars.Unlikeinvertase,sucrasehasnoactiononlowdegreeofpolymerization(DP)fructooligosaccharides,suchaskestoseorkestotetraose.Fructanishydrolyzedtofructoseandglucosebythecombinedactionofhighlypurifiedexo-andendo-inulinases,andthesesugarsaremeasuredbythep-hydroxybenzoicacidhydrazidereducingsugarmethod.Specificmeasurementofβ-glucanincerealflourandfoodextractsrequirestheuseofhighlypurifiedendo-1,3:1,4β-glucanaseandA.nigerβ-glucosidase.β-glucosidasefromalmondsdoesnotcompletelyhydrolyzemixedlinkageβ-glucooligosaccharidesfrombarleyoroatβ-glucan.Contaminationoftheseenzymeswithstarch,maltosaccharide,orsucrose-hydrolyzingenzymesresultsinproductionoffreeglucosefromasourceotherthanβ-glucan,andthusanoverestimationofβ-glucancontent.Theglucoseoxidaseandperoxidaseusedintheglucosedeterminationreagentmustbeessentiallydevoidofcatalaseandα-andβ-glucosidase.Twoissuesindietaryfibermeasurement.McCleary,B.V.(2001).CerealFoodsWorld,46,164-165.LinktoArticleReadAbstractEnzymeactivityandpurityofthesetopics,theeasiesttodealwithistheimportanceofenzymepurityandactivity.Asascientistactivelyinvolvedinpolysaccharideresearchoverthepast25years,Ihavecometoappreciatetheimportanceofenzymepurityandspecificityinpolysaccharidemodificationandmeasurement(7).Thesefactorstranslatedirectlytodietaryfiber(DF)methodology,becausethemajorcomponentsofDFarecarbohydratepolymersandoligomers.ThecommitteereportpublishedintheMarchissueofCerealFOODSWORLDrefersonlytothemethodologyformeasuringenzymepurityandactivity(8)thatleduptheAOACmethod985.29(2).Inthisworkenzymepuritywasgaugedbythelackofhydrolysis(i.e.,completerecovery)ofaparticularDFcomponent(e.g.β-glucan,larchgalactanorcitruspectin).Enzymeactivitywasmeasuredbytheabilitytocompletelyhydrolyzerepresentativestarchandprotein(namelywheatstarchandcasein).Theserequirementsandrestrictionsonenzymepurityandactivitywereadequateatthetimethemethodwasinitiallydevelopedandservedasausefulworkingguide.However,itwasrecognizedthattherewasaneedformorestringentqualitydefinitionsandassayproceduresforenzymesusedinDFmeasurements.Dietaryfibreanalysis.McCleary,B.V.(2003).ProceedingsoftheNutritionSociety,62,3-9.LinktoArticleReadAbstractThe"goldstandard"methodforthemeasurementoftotaldietaryfibreisthatoftheAssociationofOfficialAnalyticalChemists(2000;method985.29).Thisprocedurehasbeenmodifiedtoallowmeasurementofsolubleandinsolubledietaryfibre,andbuffersemployedhavebeenimproved.However,therecognitionofthefactthatnon-digestibleoligosaccharidesandresistantstarchalsobehavephysiologicallyasdietaryfibrehasnecessitatedare-examinationofthedefinitionofdietaryfibre,andinturn,are-evaluationofthedietaryfibremethodsoftheAssociationofOfficialAnalyticalChemists.Withthisrealisation,theAmericanAssociationofCerealChemistsappointedascientificreviewcommitteeandchargeditwiththetaskofreviewingand,ifnecessary,updatingthedefinitionofdietaryfibre.Itorganisedvariousworkshopsandacceptedcommentsfrominterestedpartiesworldwidethroughaninteractivewebsite.Morerecently,the(US)FoodandNutritionBoardoftheInstituteofHealth,NationalAcademyofSciences,undertheoversightoftheStandingCommitteeontheScientificEvaluationofDietaryReferenceIntakes,assembledapaneltodevelopaproposeddefinition(s)ofdietaryfibre.Variouselementsofthesedefinitionswereinagreement,butnotall.Whatwasclearfrombothreviewsisthatthereisanimmediateneedtore-evaluatethemethodsthatareusedfordietaryfibremeasurementandtomakeappropriatechangeswhererequired,andtofindnewmethodstofillgaps.Inthispresentation,the"stateoftheart"inmeasurementoftotaldietaryfibreanddietaryfibrecomponentswillbedescribedanddiscussed,togetherwithsuggestionsforfutureresearch.Measurementofnoveldietaryfibres.McCleary,B.V.&Rossiter,P.(2004).JournalofAOACInternational,87(3),707-717.LinktoArticleReadAbstractWiththerecognitionthatresistantstarch(RS)andnondigestibleoligosaccharides(NDO)actphysiologicallyasdietaryfiber(DF),aneedhasdevelopedforspecificandreliableassayproceduresforthesecomponents.TheabilityofAOACDFmethodstoaccuratelymeasureRSisdependentonthenatureoftheRSbeinganalyzed.Ingeneral,NDOarenotmeasuredatallbyAOACDFMethods985.29or991.43,theoneexceptionbeingthehighmolecularweightfractionoffructo-oligosaccharides.ValuesobtainedforRS,ingeneral,arenotingoodagreementwithvaluesobtainedbyinvitroproceduresthatmorecloselyimitatetheinvivosituationinthehumandigestivetract.Consequently,specificmethodsfortheaccuratemeasurementofRSandNDOhavebeendevelopedandvalidatedthroughinterlaboratorystudies.Inthispaper,modificationstoAOACfructanMethod999.03toallowaccuratemeasurementofenzymicallyproducedfructo-oligosaccharidesaredescribed.SuggestedmodificationstoAOACDFmethodstoensurecompleteremovaloffructanandRS,andtosimplifypHadjustmentbeforeamyloglucosidaseaddition,arealsodescribed.Anintegratedprocedureforthemeasurementoftotaldietaryfibre(includingresistantstarch),non-digestibleoligosaccharidesandavailablecarbohydrates.McCleary,B.V.(2007).AnalyticalandBioanalyticalChemistry,389(1),291-308.LinktoArticleReadAbstractAmethodisdescribedforthemeasurementofdietaryfibre,includingresistantstarch(RS),non-digestibleoligosaccharides(NDO)andavailablecarbohydrates.Basically,thesampleisincubatedwithpancreaticα-amylaseandamyloglucosidaseunderconditionsverysimilartothosedescribedinAOACOfficialMethod2002.02(RS).Reactionisterminatedandhighmolecularweightresistantpolysaccharidesareprecipitatedfromsolutionwithalcoholandrecoveredbyfiltration.RecoveryofRS(formostRSsources)isinlinewithpublisheddatafromileostomystudies.Theaqueousethanolextractisconcentrated,desaltedandanalysedforNDObyhigh-performanceliquidchromatographybyamethodsimilartothatdescribedbyOkuma(AOACMethod2001.03),exceptthatforlogisticalreasons,D-sorbitolisusedastheinternalstandardinplaceofglycerol.Availablecarbohydrates,definedasD-glucose,D-fructose,sucrose,theD-glucosecomponentoflactose,maltodextrinsandnon-resistantstarch,aremeasuredasD-glucoseplusD-fructoseinthesampleafterhydrolysisofoligosaccharideswithamixtureofsucrase/maltaseplusβ-galactosidase.Developmentandevaluationofanintegratedmethodforthemeasurementoftotaldietaryfibre.McCleary,B.V.,Mills,C.&Draga,A.(2009).QualityAssuranceandSafetyofCrops&Foods,1(4),213–224.LinktoArticleReadAbstractAnintegratedtotaldietaryfibre(TDF)method,consistentwiththerecentlyacceptedCODEXdefinitionofdietaryfibre,hasbeendeveloped.TheCODEXCommitteeonNutritionandFoodsforSpecialDietaryUses(CCNFSDU)hasbeendeliberatingforthepast8yearsonadefinitionfordietaryfibrethatcorrectlyreflectsthecurrentconsensusthinkingonwhatshouldbeincludedinthisdefinition.Asthisdefinitionwasevolving,itbecameevidenttousthatneitherofthecurrentlyavailablemethodsforTDF(AOACOfficialMethods985.29and991.43),noracombinationoftheseandothermethods,couldmeettheserequirements.Consequently,wedevelopedanintegratedTDFprocedure,basedontheprincipalsofAOACOfficialMethods2002.02,991.43and2001.03,thatiscompliantwiththenewCODEXdefinition.Thisprocedurequantitateshigh-andlow-molecularweightdietaryfibresasdefined,givinganaccurateestimateofresistantstarchandnon-digestibleoligosaccharidesalsoreferredtoaslow-molecularweightsolubledietaryfibre.Inthispaper,themethodisdiscussed,modificationstothemethodtoimprovesimplicityandreproducibilityaredescribed,andtheresultsofthefirstroundsofinterlaboratoryevaluationarereported.Determinationoftotaldietaryfiber(CODEXdefinition)byenzymatic-gravimetricmethodandliquidchromatography:collaborativestudy.McCleary,B.V.,DeVries,J.W.,Rader,J.I.,Cohen,G.,Prosky,L.,Mugford,D.C.,Champ,M.&Okuma,K.(2010).JournalofAOACInternational,93(1),221-233.LinktoArticleReadAbstractAmethodforthedeterminationoftotaldietaryfiber(TDF),asdefinedbytheCODEXAlimentarius,wasvalidatedinfoods.BasedupontheprinciplesofAOACOfficialMethodsSM985.29,991.43,2001.03,and2002.02,themethodquantitateshigh-andlow-molecular-weightdietaryfiber(HMWDFandLMWDF,respectively).In2007,McClearydescribedamethodofextendedenzymaticdigestionat37°CtosimulatehumanintestinaldigestionfollowedbygravimetricisolationandquantitationofHMWDFandtheuseofLCtoquantitatelow-molecular-weightsolubledietaryfiber(LMWSDF).Themethodthusquantitatesthecompleterangeofdietaryfibercomponentsfromresistantstarch(byutilizingthedigestionconditionsofAOACMethod2002.02)todigestionresistantoligosaccharides(byincorporatingthedeionizationandLCproceduresofAOACMethod2001.03).ThemethodwasevaluatedthroughanAOACcollaborativestudy.Eighteenlaboratoriesparticipatedwith16laboratoriesreturningvalidassaydatafor16testportions(eightblindduplicates)consistingofsampleswitharangeoftraditionaldietaryfiber,resistantstarch,andnondigestibleoligosaccharides.Thedietaryfibercontentoftheeighttestpairsrangedfrom11.57to47.83.DigestionofsamplesundertheconditionsofAOACMethod2002.02followedbytheisolationandgravimetricproceduresofAOACMethods985.29and991.43resultsinquantitationofHMWDF.ThefiltratefromthequantitationofHMWDFisconcentrated,deionized,concentratedagain,andanalyzedbyLCtodeterminetheLMWSDF,i.e.,allnondigestibleoligosaccharidesofdegreeofpolymerization3.TDFiscalculatedasthesumofHMWDFandLMWSDF.Repeatabilitystandarddeviations(Sr)rangedfrom0.41to1.43,andreproducibilitystandarddeviations(SR)rangedfrom1.18to5.44.Theseresultsarecomparabletootherofficialdietaryfibermethods,andthemethodisrecommendedforadoptionasOfficialFirstAction.Determinationofinsoluble,soluble,andtotaldietaryfiber(codexdefinition)byenzymatic-gravimetricmethodandliquidchromatography:CollaborativeStudy.McCleary,B.V.,DeVries,J.W.,Rader,J.I.,Cohen,G.,Prosky,P.,Mugford,D.C.,Champ,M.&Okuma,K.(2012).JournalofAOACInternational,95(3),824-844.LinktoArticleReadAbstractAmethodforthedeterminationofinsoluble(IDF),soluble(SDF),andtotaldietaryfiber(TDF),asdefinedbytheCODEXAlimentarius,wasvalidatedinfoods.BasedupontheprinciplesofAOACOfficialMethodsSM985.29,991.43,2001.03,and2002.02,themethodquantitateswater-insolubleandwater-solubledietaryfiber.ThismethodextendsthecapabilitiesofthepreviouslyadoptedAOACOfficialMethod2009.01,TotalDietaryFiberinFoods,Enzymatic-Gravimetric-LiquidChromatographicMethod,applicabletoplantmaterial,foods,andfoodingredientsconsistentwithCODEXDefinition2009,includingnaturallyoccurring,isolated,modified,andsyntheticpolymersmeetingthatdefinition.ThemethodwasevaluatedthroughanAOAC/AACCcollaborativestudy.Twenty-twolaboratoriesparticipated,with19laboratoriesreturningvalidassaydatafor16testportions(eightblindduplicates)consistingofsampleswitharangeoftraditionaldietaryfiber,resistantstarch,andnondigestibleoligosaccharides.Thedietaryfibercontentoftheeighttestpairsrangedfrom10.45to29.90%.DigestionofsamplesundertheconditionsofAOAC2002.02followedbytheisolation,fractionation,andgravimetricproceduresofAOAC985.29(anditsextensions991.42and993.19)and991.43resultsinquantitationofIDFandsolubledietaryfiberthatprecipitates(SDFP).Thefiltratefromthequantitationofwater-alcohol-insolubledietaryfiberisconcentrated,deionized,concentratedagain,andanalyzedbyLCtodeterminetheSDFthatremainssoluble(SDFS),i.e.,alldietaryfiberpolymersofdegreeofpolymerization=3andhigher,consistingprimarily,butnotexclusively,ofoligosaccharides.SDFiscalculatedasthesumofSDFPandSDFS.TDFiscalculatedasthesumofIDFandSDF.Thewithin-laboratoryvariability,repeatabilitySD(Sr),forIDFrangedfrom0.13to0.71,andthebetween-laboratoryvariability,reproducibilitySD(sR),forIDFrangedfrom0.42to2.24.Thewithin-laboratoryvariabilitysrforSDFrangedfrom0.28to1.03,andthebetween-laboratoryvariabilitysRforSDFrangedfrom0.85to1.66.Thewithin-laboratoryvariabilitysrforTDFrangedfrom0.47to1.41,andthebetween-laboratoryvariabilitysRforTDFrangedfrom0.95to3.14.Thisiscomparabletootherofficialandapproveddietaryfibermethods,andthemethodisrecommendedforadoptionasOfficialFirstAction.MeasurementoftotaldietaryfiberusingAOACmethod2009.01(AACCInternationalapprovedmethod32-45.01):Evaluationandupdates.McCleary,B.V.,Sloane,N.,Draga,A.&Lazewska,I.(2013).CerealChemistry,90(4),396-414.LinktoArticleReadAbstractTheCodexCommitteeonMethodsofAnalysisandSamplingrecentlyrecommended14methodsformeasurementofdietaryfiber,eightofthesebeingtypeImethods.OfthesetypeImethods,AACCInternationalApprovedMethod32-45.01(AOACmethod2009.01)istheonlyprocedurethatmeasuresallofthedietaryfibercomponentsasdefinedbyCodexAlimentarius.OthermethodssuchastheProskymethod(AACCIApprovedMethod32-05.01)givesimilaranalyticaldataforthehigh-molecular-weightdietaryfibercontentsoffoodandvegetableproductslowinresistantstarch.Inthecurrentwork,AACCIApprovedMethod32-45.01hasbeenmodifiedtoallowaccuratemeasurementofsampleshighinparticularfructooligosaccharides:forexample,fructotriose,which,intheHPLCsystemused,chromatographsatthesamepointasdisaccharides,meaningthatitiscurrentlynotincludedinthemeasurement.Incubationoftheresistantoligosaccharidesfractionwithsucrase/β-galactosidaseremovesdisaccharidesthatinterferewiththequantitationofthisfraction.Thedietaryfibervalueforresistantstarchtype4(RS4),variessignificantlywithdifferentanalyticalmethods,withmuchlowervaluesbeingobtainedwithAACCIApprovedMethod32-45.01thanwith32-05.01.ThisdifferenceresultsfromthegreatersusceptibilityofRS4tohydrolysisbypancreaticα-amylasethanbybacterialα-amylase,andalsoagreatersusceptibilitytohydrolysisatlowertemperatures.OnhydrolysisofsampleshighinstarchintheassayformatofAACCIApprovedMethod32-45.01(AOACmethod2009.01),resistantmaltodextrinsareproduced.Themajorcomponentisaheptasaccharidethatishighlyresistanttohydrolysisbymostofthestarch-degradingenzymesstudied.However,itishydrolyzedbythemaltase/amyloglucosidase/isomaltaseenzymecomplexpresentinthebrushborderliningofthesmallintestine.Asaconsequence,AOACmethods2009.01and2011.25(AACCIApprovedMethods32-45.01and32-50.01,respectively)mustbeupdatedtoincludeanadditionalincubationwithamyloglucosidasetoremovetheseoligosaccharides.ModificationtoAOACOfficialMethods2009.01and2011.25toallowforminoroverestimationoflowmolecularweightsolubledietaryfiberinsamplescontainingstarch.McCleary,B.V.(2014).JournalofAOACInternational,97(3),896-901.LinktoArticleReadAbstractAOACOfficialMethods2009.01and2011.25havebeenmodifiedtoallowremovalofresistantmaltodextrinsproducedonhydrolysisofvariousstarchesbythecombinationofpancreaticα-amylaseandamyloglucosidase(AMG)usedintheseassayprocedures.Themajorresistantmaltodextrin,63,65-di-α-D-glucosylmaltopentaose,ishighlyresistanttohydrolysisbymicrobialα-glucosidases,isoamylase,pullulanase,pancreatic,bacterialandfungalα-amylaseandAMG.However,thisoligosaccharideishydrolyzedbythemucosalα-glucosidasecomplexofthepigsmallintestine(whichissimilartothehumansmallintestine),andthusmustberemovedintheanalyticalprocedure.HydrolysisoftheseoligosaccharideshasbeenbyincubationwithahighconcentrationofapurifiedAMGat60°C.ThisincubationresultsinnohydrolysisorlossofotherresistantoligosaccharidessuchasFOS,GOS,XOS,resistantmaltodextrins(e.g.,Fibersol2)orpolydextrose.TheeffectofthisadditionalincubationwithAMGonthemeasuredleveloflowmolecularweightsolubledietaryfiber(SDFS)andoftotaldietaryfiberinabroadrangeofsamplesisreported.Resultsfromthisstudydemonstratethattheproposedmodificationcanbeusedwithconfidenceinthemeasurementofdietaryfiber.Physical,microscopicandchemicalcharacterisationofindustrialryeandwheatbransfromtheNordiccountries.Kamal-Eldin,A.,Lærke,H.N.,Knudsen,K.E.B.,Lampi,A.M.,Piironen,V.,Adlercreutz,H.,Katina,K.,Poutanen,K.&Aman,P.(2009).Food&nutritionresearch,53.LinktoArticleReadAbstractBackground:Epidemiologicalstudiesshowinverserelationshipbetweenintakeofwholegraincerealsandseveralchronicdiseases.Componentsandmechanismsbehindpossibleprotectiveeffectsofwholegraincerealsarepoorlyunderstood.Objective:Tocharacterisecommercialryebranpreparations,comparedtowheatbran,regardingstructureandcontentofnutrientsaswellasanumberofpresumablybioactivecompounds.Design:SixdifferentryebransfromSweden,DenmarkandFinlandwereanalysedandcomparedwithtwowheatbransregardingcolour,particlesizedistribution,microscopicstructuresandchemicalcompositionincludingproximalcomponents,vitamins,mineralsandbioactivecompounds.Results:Ryebransweregenerallygreenerincolourandsmallerinparticlesizethanwheatbrans.Theryebransvariedconsiderablyintheirstarchcontent(13.2–;28.3%),whichreflectedvariableinclusionofthestarchyendosperm.Althoughryeandwheatbranscontainedcomparablelevelsoftotaldietaryfibre,theydifferedintherelativeproportionsoffibrecomponents(i.e.arabinoxylan,β-glucan,cellulose,fructanandKlasonlignin).Generally,ryebranscontainedlesscelluloseandmoreβ-glucanandfructanthanwheatbrans.Withinsmallvariations,theryeandwheatbranswerecomparableregardingthecontentsoftocopherols/tocotrienols,totalfolate,sterols/stanols,phenolicacidsandlignans.Ryebranhadlessglycinebetaineandmorealkylresorcinolsthanwheatbrans.Conclusions:Theobservedvariationinthechemicalcompositionofindustriallyproducedryebranscallsfortheneedofstandardisationofthiscommodity,especiallywhenusedasafunctionalingredientinfoods.Relationshipofgrainfructancontenttodegreeofpolymerisationindifferentbarleys.Nemeth,C.,Andersson,A.A.M.,Andersson,R.,Mangelsen,E.,Sun,C.&Åman,P.(2014).FoodandNutritionSciences,5,581-589.LinktoArticleReadAbstractFructansareimportantinthesurvivalofplantsandalsovaluableforhumansaspotentiallyhealthpromotingfoodingredients.Inthisstudyfructancontentandcompositionweredeterminedingrainsof20barleybreedinglinesandcultivarswithawidevariationinchemicalcomposition,morphologyandcountryoforigin,grownatonesiteinChile.Therewassignificantgenotypicvariationingrainfructancontentrangingfrom0.9%to4.2%ofgraindryweight.Fructandegreeofpolymerisation(DP)wasanalysedusinghigh-performanceanion-exchangechromatographywithpulsedamperometricdetection(HPAEC-PAD).Changesinthedistributionofdifferentchainlengthsandthepatternofstructuresoffructanweredetectedwithincreasingamountoffructaninthedifferentbarleys.Apositivecorrelationwasfoundbetweenfructancontentandtherelativeamountoflongchainfructan(DP>9)(r=0.54,p=0.021).Ourresultsprovideabasisforselectingpromisingbarleylinesandcultivarsforfurtherresearchonfructaninbarleybreedingwiththeaimtoproducehealthyfoodproducts.Howdoesthepreparationofryeporridgeaffectmolecularweightdistributionofextractabledietaryfibers?Rakha,A.,Åman,P.&Andersson,R.(2011).Internationaljournalofmolecularsciences,12(5),3381-3393.LinktoArticleReadAbstractExtractabledietaryfiber(DF)playsanimportantroleinnutrition.ThisstudyonporridgemakingwithwholegrainryeinvestigatedtheeffectofresttimeofflourslurriesatroomtemperaturebeforecookingandamountofflourandsaltintherecipeonthecontentofDFcomponentsandmolecularweightdistributionofextractablefructan,mixedlinkage(1→3)(1→4)-β-D-glucan(β-glucan)andarabinoxylan(AX)intheporridge.ThecontentoftotalDFwasincreased(fromabout20%to23%ofdrymatter)duringporridgemakingduetoformationofinsolubleresistantstarch.Asmallbutsignificantincreaseintheextractabilityofβ-glucan(P=0.016)andAX(P=0.002)duetoresttimewasalsonoted.ThemolecularweightofextractablefructanandAXremainedstableduringporridgemaking.However,incubationoftheryeflourslurriesatincreasedtemperatureresultedinasignificantdecreaseinextractableAXmolecularweight.Themolecularweightofextractableβ-glucandecreasedgreatlyduringaresttimebeforecooking,mostlikelybytheactionofendogenousenzymes.Theamountofsaltandflourusedintherecipehadsmallbutsignificanteffectsonthemolecularweightofβ-glucan.TheseresultsshowthatwholegrainryeporridgemadewithoutaresttimebeforecookingcontainsextractableDFcomponentsmaintaininghighmolecularweights.Highmolecularweightismostlikelyofnutritionalimportance.Baselinesrepresentingbloodglucoseclearanceimproveinvitropredictionoftheglycaemicimpactofcustomarilyconsumedfoodquantities.Monro,J.A.,Mishra,S.&Venn,B.(2010).BritishJournalofNutrition,103(2),295-305.LinktoArticleReadAbstractGlycaemicresponsestofoodsreflectthebalancebetweenglucoseloadinginto,anditsclearancefrom,theblood.Currentinvitromethodsforglycaemicanalysisdonottakeintoaccountthekeyroleofglucosedisposal.Thepresentstudyaimedtodevelopafoodintake-sensitivemethodformeasuringtheglycaemicimpactoffoodquantitiesusuallyconsumed,asthedifferencebetweenreleaseofglucoseequivalents(GGE)fromfoodduringinvitrodigestionandacorrespondingestimateofclearanceofthemfromtheblood.Fivefoods–whitebread,fruitbread,mueslibar,mashedpotatoandchickpeas–wereconsumedonthreeoccasionsbytwentyvolunteerstoprovidebloodglucoseresponse(BGR)curves.GGEreleaseduringinvitrodigestionofthefoodswasalsoplotted.GlucosedisposalratesestimatedfromdownwardslopesoftheBGRcurvesallowedGGEdose-dependentcumulativeglucosedisposaltobecalculated.BysubtractingcumulativeglucosedisposalfromcumulativeinvitroGGErelease,accuracyinpredictingtheinvitroglycaemiceffectfrominvitroGGEvalueswasgreatlyimproved.GGEinvivo=0·99GGEinvitro+0·75(R20·88).FurThermore,thedifferencebetweenthecurvesofcumulativeGGEreleaseanddisposalcloselymimickedinvivoincrementalBGRcurves.Weconcludethatvalidmeasurementoftheglycaemicimpactoffoodsmaybeobtainedinvitro,andexpressedasgramsofglucoseequivalentsperfoodquantity,bytakingaccountnotonlyofGGEreleasefromfoodduringinvitrodigestion,butalsoofbloodglucoseclearanceinresponsetothefoodquantity.Effectofprocessingonslowlydigestiblestarchandresistantstarchinpotato.Mishra,S.,Monro,J.&Hedderley,D.(2008).Starch‐Stärke,60(9),500-507.LinktoArticleReadAbstractTheeffectofanumberoflaboratory-scalepretreatmentsontheproportionsofrapidlydigested(RDS),slowlydigested(SDS)andresistantstarch(RS)inrawandcookedpotatohasbeenexaminedusinganinvitrodigestionprocedure.PotatoesofthevarietyFrisiawerepreparedinthreestates:raw,cooked,andcookedfollowedbyacoldtreatment(4°C,twodays).Eachpreparationwasthensubjectedintriplicatetofreeze-drying,coarselymincing,pasting,freezing,dry-millingafterfreeze-drying,in22differentcombinations,beforedigesting.Inrawpotato,verylittleRDSandSDS(95%TS)infreshly-cookedpotato,butafterpost-cookingcoldtreatmentmuchoftheRDStransformedtoSDS,whichreachedamaximumofabout45%TS.SDSformationwasindependentofthedegreeoftissuedisruptionaftercooking,andwasgenerallyassociatedwithformationofRS,however,freezingaftercookingallowedSDSformationwithoutprolongedcoldtreatmentandwithverylittleassociatedRS(SDS35%andRS4%ofTS).Freeze-dryingcausedanincreaseinRSinmosttreatmentsofthecookedpotatoes.Theobservedeffectsprovidedguidanceforsamplehandlinginpotatoresearch,butalsosuggestedseveralapproachestotheenrichmentofSDSand/orRS,withaconcurrentreductioninRDS,thatcouldbeusedtoimprovethenutritionalprofileofpotatoproductsbydecreasingRDS(loweredglycaemicimpact),andincreasingSDS(moresustainedenergyavailability)andRS(prebioticbenefits).InvestigationofdigestibilityinvitroandphysicochemicalpropertiesofA-andB-typestarchfromsoftandhardwheatflour.Liu,Q.,Gu,Z.,Donner,E.,Tetlow,I.&Emes,M.(2007).CerealChemistry,84(1),15-21.LinktoArticleReadAbstractInthisstudy,thefunctionalpropertiesofA-andB-typewheatstarchgranulesfromtwocommercialwheatflourswereinvestigatedfordigestibilityinvitro,chemicalcomposition(e.g.,amylose,protein,andashcontent),gelatinization,retrogradation,andpastingproperties.ThebranchchainlengthandchainlengthdistributionoftheseA-andB-typewheatstarchgranuleswerealsodeterminedusinghigh-performanceanionexchangechromatography(HPAEC).Wheatstarcheswithdifferentgranularsizesnotonlyhaddifferentdegreesofenzymatichydrolysisandthermalandpastingproperties,butalsodifferentmolecularcharacteristics.Differentamylosecontent,proteincontent,andbranchchainlengthofamylopectininA-andB-typewheatstarchgranulescouldalsobethemajorfactorsbesidesgranularsizefordifferentdigestibilityandotherfunctionalpropertiesofstarch.ThedataindicatethatdifferentwheatcultivarswithdifferentproportionofA-andB-typegranularstarchcouldresultindifferentdigestibilityinwheatproducts.Determinationofresistantshort-chaincarbohydrates(non-digestibleoligosaccharides)usinggas–liquidchromatography.Quigley,M.E.,Hudson,G.J.&Englyst,H.N.(1999).FoodChemistry,65(3),381-390.LinktoArticleReadAbstractWehaveproposedthetermshort-chaincarbohydrates(SCC)forthosespecies,otherthanthefreesugars,thataresolublein80%ethanolunderwell-definedconditions.WedescribeatechniqueforthemeasurementofresistantSCC(RSCC),whicharenotsusceptibletopancreaticamylaseorthebrushborderenzymesandthereforesometimestermednon-digestibleoligosaccharides.Intheprocedure,alpha-glucans(starchandmaltodextrins)arehydrolysedenzymaticallytoglucoseandthenon-starchpolysaccharides(NSP)areprecipitatedinethanol.Fructansarehydrolysedenzymaticallyandthemonosaccharideconstituentsarereducedtoacid-stablealditolderivativesbeforetheremainingRSCCarehydrolysedwithsulphuricacid.Alltheconstituentsugarsaremeasuredasalditolacetatederivativesbygas–liquidchromatography.TheprotocolallowsboththemeasurementoftotalRSCCandaseparate,specificmeasurementoffructans.Thephysicochemicalpropertiesandinvitrodigestibilityofselectedcereals,tubersandlegumesgrowninChina.Liu,Q.,Donner,E.,Yin,Y.,Huang,R.L.&Fan,M.Z.(2006).FoodChemistry,99(3),470-477.LinktoArticleReadAbstractDigestibility,gelatinization,retrogradationandpastingpropertiesofstarchinvariouscereal,tuberandlegumefloursweredetermined.Rapidlyandslowlydigestiblestarchandresistantstarchwerepresentin11selectedflours.Ingeneral,cerealstarchesweremoredigestiblethanlegumestarchesandtuberstarchescontainedahighamountofresistantstarch.Thermalandrheologicalpropertiesoffloursweredifferentdependingonthecropsource.Developmentandphysicochemicalcharacterizationofnewresistantcitratestarchfromdifferentcornstarches.Xie,X.S.&Liu,Q.(2004).Starch‐Stärke,56(8),364-370.LinktoArticleReadAbstractResistantstarchhasdrawnbroadinterestforbothpotentialhealthbenefitsandfunctionalproperties.Inthisstudy,atechnologywasdevelopedtoincreaseresistantstarchcontentofcornstarchusingesterificationwithcitricacidatelevatedtemperature.Waxycorn,normalcornandhigh-amylosecornstarcheswereusedasmodelstarches.Citricacid(40%ofstarchdryweight)wasreactedwithcornstarchatdifferenttemperatures(120–150°C)fordifferentreactiontimes(3–9h).Theeffectofreactionconditionsonresistantstarchcontentinthecitratecornstarchwasinvestigated.Whenconductingthereactionat140°Cfor7h,thehighestresistantstarchcontentwasfoundinwaxycorncitratestarch(87.5%)withthehighestdegreeofsubstitution(DS,0.16)ofallstarches.High-amylosecornstarchhad86.4%resistantstarchcontentand0.14DS,andnormalcornstarchhad78.8%resistantstarchand0.12DS.Thephysicochemicalpropertiesofthesecitratestarcheswerecharacterizedusingvariousanalyticaltechniques.Inthepresenceofexcesswateruponheating,citratestarchmadefromwaxycornstarchhadnopeakintheDSCthermogram,andsmallpeakswerefoundfornormalcornstarch(0.4J/g)andHylonVIIstarch(3.0J/g)inthethermograms.Thisindicatesthatcitratesubstitutionchangesgranuleproperties.Therearenoretrogradationpeaksinthethermogramswhenstarchwasreheatedafter2weeksstorageat5°C.AllthecitratestarchesshowednopeaksinRVApastingcurves,indicatingcitratesubstitutionchangesthepastingpropertiesofcornstarchaswell.Moreover,citratestarchfromwaxycornismorethermallystablethantheothercitratestarches.Determinationof“NetCarbohydrates”usinghigh-performanceanionexchangechromatography.Lilla,Z.,Sullivan,D.,Ellefson,W.,Welton,K.&Crowley,R.(2005).JournalofAOACInternational,88(3),714-719.LinktoArticleReadAbstractForlabelingpurposes,thecarbohydratecontentoffoodshastraditionallybeendeterminedbydifference.Thisvalueincludessugars,starches,fiber,dextrins,sugaralcohols,polydextrose,andvariousotherorganiccompounds.Insomecases,thecurrentmethodmaylacksufficientspecificity,precision,andaccuracy.Thesearesubsequentlyquantitatedbyhighperformanceanionexchangechromatographywithpulsedamperometricdetectionandexpressedastotalnonfibersaccharidesorpercent“netcarbohydrates.”Inthisresearch,anewmethodwasdevelopedtoaddressthisneed.Themethodconsistsofenzymedigestionstoconvertstarches,dextrins,sugars,andpolysaccharidestotheirrespectivemonosaccharidecomponents.Thesearesubsequentlyquantifiedbyhigh-performanceanionexchangechromatographywithpulsedamperometricdetectorandexpressedastotalnonfibersaccharidesorpercent“netcarbohydrates.”Hydrolyzedendproductsofvariousnovelfibersandsimilarcarbohydrateshavebeenevaluatedtoensurethattheydonotregisterasfalsepositivesinthenewtestmethod.Thedatageneratedusingthe“netcarbohydrate”methodwere,inmanycases,significantlydifferentthanthevaluesproducedusingthetraditionalmethodology.Therecoveriesobtainedinafortifieddrinkmatrixrangedfrom94.9to105%.Thecoefficientofvariationwas3.3%.CerealByproductshavePrebioticPotentialinMiceFedaHigh-fatDiet.Berger,K.,Falck,P.,Linninge,C.,Nilsson,U.,Axling,U.,Grey,C.,Stålbrand,H.,Karlsson,E.N.,Nyman,M.,Holm,C.&Adlercreutz,P.(2014).JournalofAgriculturalandFoodChemistry,62(32),8169-8178.LinktoArticleReadAbstractBarleyhusks,ryebran,andafiberresiduefromoatmilkproductionwereprocessedbyheatpretreatment,variousseparationsteps,andtreatmentwithanendoxylanaseinordertoimprovetheprebioticpotentialofthesecerealbyproducts.Metabolicfunctionswereintendedtoimprovealongwithimprovedmicrobialactivity.Theproductsobtainedwereincludedinahigh-fatmousedietsothatalldietscontained5%dietaryfiber.Inaddition,high-fatandlow-fatcontrolsaswellaspartiallyhydrolyzedguargumwereincludedinthestudy.Thesolublefiberproductobtainedfromryebrancausedasignificantincreaseinthebifidobacteria(logcopiesof16SrRNAgenes;median(25–75percentile):6.38(6.04–6.66)and7.47(7.30–7.74),respectively;ppExtractionofβ-glucanfromoatsforsolubledietaryfiberqualityanalysis.Doehlert,D.C.,Simsek,S.&McMullen,M.S.(2012).CerealChemistry,89(5),230-236.LinktoArticleReadAbstractExtractionprotocolsforβ-glucanfromoatflourweretestedtodetermineoptimalconditionsforβ-glucanqualitytesting,whichincludedextractabilityandmolecularweight.Wefoundmassyieldsofβ-glucanwereconstantatalltemperatures,pHvalues,andflour-to-waterratios,aslongassufficienttimeandenoughrepeatextractionswereperformedandnohydrolyticenzymeswerepresent.Extractscontainedabout30–60%β-glucan,withlowerproportionsassociatedwithhigherextractiontemperaturesinwhichmorestarchandproteinwereextracted.Allcommercialstarchhydrolyticenzymestested,eventhosethatareconsideredhomogenous,degradedβ-glucanapparentmolecularweightasevaluatedbysize-exclusionchromatography.Higherconcentrationβ-glucansolutionscouldbepreparedbycontrollingtheflour-to-waterratioinextractions.Eightgramsofflourper50mLofwatergeneratedthehighestnativeβ-glucanconcentrations.Routineextractionscontained2gofenzyme-inactivatedflourin50mLofwaterwith5mMsodiumazide(asanantimicrobial),whichwerestirredovernight,centrifuged,andthesupernatantboiledfor10min.Thepolymerextractedhadamolecularweightofabout2millionandwasstableatroomtemperatureforatleastamonth.Effectofdietarystarchsourceongrowthperformances,digestibilityandqualitytraitsof

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