ETHYL PROTOCATECHUATE-原儿茶酸乙酯.pdf

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1、ETHYLPROTOCATECHUATEPreparedatthe17thJECFA(1973),publishedinFNP4(1978)andinFNP52(1992).Metalsandarsenicspecificationsrevisedatthe61stJECFA(2003).NoADIwasallocatedatthe17thJECFA(1973)DEFINITIONChemicalnamesEthylprotocatechuate,Ethyl3,4-dihydroxybenzoate,Ethylesterof3,4-dihy

2、droxybenzoicacidC.A.S.number3943-89-3ChemicalformulaC9H10O4StructuralformulaFormulaweight182.2AssayInformationrequestedDESCRIPTIONWhiteorpalebrownishyellow,crystallinepowder;odourlessorhasafaintphenol-likeodourFUNCTIONALUSESAntioxidantCHARACTERISTICSIDENTIFICATIONSolubilit

3、y(Vol.4)Insolubleinwater;solubleinethanolMeltingrange(Vol.4)o132-135TestforethanolDissolve0.5gofthesamplein10mlofsodiumhydroxideTSanddistil.To4mloftheinitialcleardistillateaddanequalvolumeofsodiumhydroxideTSand2or3dropsofiodineTS,andheatthesolution:iodoformodourevolves.Tes

4、tforprotocatechuicAcidifytheresiduefromthedistillationintheTestforethanol,toprecipitateacidanacidwhichonrecrystallizationhasameltingrangeof190-194ºwithdecompositionTestforphenolDissolve0.1gofthesamplein5mlofethanol,andadd1dropofdilutedferricchlorideTS:agreencolourdevelopsP

5、URITYLossondrying(Vol.4)oNotmorethan0.5%(105,2h)Sulfatedash(Vol.4)Notmorethan0.05%Test4gofthesampleChlorinatedorganicNotmorethan100mg/kgaschlorinecompoundsDissolve1.07gofthesamplein10mlof0.1Nsodiumhydroxide.Acidifywithnitricacidandfilterofftheprecipitate.Mixtheprecipitatew

6、ith2gofcalciumcarbonate,drythemixtureandthenignite.Takeuptheignitionresiduein20mlofdilutenitricacidTSandfilter.Mixthesolutionwith0.5mlof0.1Nsilvernitrate.Theturbidityshouldbenotmorethanthatobtainedbytheadditionof0.5mlof0.1NsilvernitratetoasimilarvolumeofdilutenitricacidTSa

7、nd0.3mlof0.01Nhydrochloricacid.FreeacidNotmorethan0.5%,calculatedasprotocatechuicacid(7.706mgofprotocatechuicacidisequivalentto1mlof0.05NNaOH)Toamixtureof50mlofcarbondioxide-freewaterand50mlofacetone,add5dropsofbromocresolgreenTSandtitratewith0.005Nhydrochloricacidtomatcha

8、buffer(pH5.0)TScontainingthesameamountofindicator.Dissolveabout0.400gofthesamplein50mlofa