CHYMOSIN A from ESCHERICHIA COLI K-12 containing the PROCHYMOSIN A GENE- 凝乳酶(源自含凝乳酶原的大肠杆菌K12品系).pdf

《CHYMOSIN A from ESCHERICHIA COLI K-12 containing the PROCHYMOSIN A GENE- 凝乳酶(源自含凝乳酶原的大肠杆菌K12品系).pdf》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、CHYMOSINAfromESCHERICHIACOLIK-12containingthePROCHYMOSINAGENEPreparedatthe53rdJECFA(1999)andpublishedinFNP52Add7(1999),supersedingtentativespecificationspreparedatthe37thJECFA(1990),publishedinFNP52(1992).ADI"Notspecified"establishedatthe37thJECFAin1990.SYNONYMSRennin

2、,milk-clottingenzyme,chymosin,chymosinA,aspartylproteaseC.A.S.number84484-18-4SOURCESProducedintracellularlybythecontrolledfermentationofEscherichiacoliK-12containingthebovineprochymosinAgene.Thestrainisnon-pathogenicandnon-toxicogenic(forexample,JA198).Prochymosinisl

3、iberatedbycelldisruptionfollowedbyharvestingoftheprochymosinbycentrifugationormembraneconcentrationandwashingwithbuffersolution.Theresidualproductioncellsareinactivatedbyacidtreatment,thentheprochymosinisdissolvedinbuffersolutionandafterpHadjustmentthesolutionisfilter

4、ed.Prochymosinisactivatedtochymosinbyacidtreatment,followedbyfinalpurificationviaanion-exchangechromatographyandelutionwithabufferedsaltsolution.ActiveprinciplesChymosinSystematicnamesandNone(EC3.4.23.4)numbersReactionscatalyzedCleavesasinglebondinkappa-caseinDESCRIPT

5、IONClear,colourlessorslightlycolouredaqueoussolutioncontainingtheactiveenzyme;preparationsmaycontaincaramelcolourtofacilitatetheiridentificationincheesemanufacture.FUNCTIONALUSESEnzymepreparationUsedinclottingofmilkforcheeseproductionGENERALMustconformtotheGeneralSpec

6、ificationsforEnzymePreparationsusedinSPECIFICATIONSFoodProcessing(seeVolumeIntroduction)CHARACTERISTICSIDENTIFICATIONMilkclottingactivityThesampleshowsmilkclottingactivity(Vol.4)