usp38-NF33-chapter61

WhereC.sporogenesisusedasabiologicalindicator,methodsforpreparation,inoculation,andrecoverymethodsandme-diamustbeadaptedtoaccommodatetheuseofthisanaerobicsporeformer.CalculationThedeterminationofDvaluesofbiologicalindicatorscanbeperformedusingtheLimitedSpearman-Karber,SurvivalCurveMethodorStumbo-Murphy-Cochranprocedures.6,7,8ItispreferabletousethesamemethodasthatdefinedbythebiologicalindicatormanufacturertodetermineDvalues.Theuseofadifferentmethodcanresultindifferencesthataremoreanartifactofthemethodthanavariationintheperformanceofthebiologicalindicator.SurvivalTimeandKillTimeTaketwogroups,eachconsistingof10specimensoftherelevantbiologicalindicator,intheiroriginal,individualcontainers.Placethespecimensofagroupinsuitablespecimenholdersthatpermiteachspecimentobeexposedtothesterilizingcondi-tionsataspecificlocationintheBIERchamber.Exposethespecimensfortherequiredsurvivaltime,enterthechamber,andremovetheholder(s)containingthe10speci-mens.Repeattheaboveprocedureimmediately,orpreheatifasubstantialintervalhaselapsed,soastosubjectthesecondholder(s)containing10specimenssimilarlytothefirstconditions,butfortherequiredkilltime.TheSurvivaltimeandkilltimeforallmonographedbiologicalindicatorsisdescribedintheofficialmonographundertheheadingforeach.á61ñMICROBIOLOGICALEXAMINATIONOFNONSTERILEPRODUCTS:MICROBIALENUMERATIONTESTSINTRODUCTIONThetestsdescribedhereafterwillallowquantitativeenumerationofmesophilicbacteriaandfungithatmaygrowunderaerobicconditions.Thetestsaredesignedprimarilytodeterminewhetherasubstanceorpreparationcomplieswithanestablishedspecificationformicrobiologicalquality.Whenusedforsuchpurposes,followtheinstructionsgivenbelow,includingthenumberofsam-plestobetaken,andinterprettheresultsasstatedbelow.Themethodsarenotapplicabletoproductscontainingviablemicroorganismsasactiveingredients.Alternativemicrobiologicalprocedures,includingautomatedmethods,maybeused,providedthattheirequivalencetothePharmacopeialmethodhasbeendemonstrated.GENERALPROCEDURESCarryoutthedeterminationunderconditionsdesignedtoavoidextrinsicmicrobialcontaminationoftheproducttobeex-amined.Theprecautionstakentoavoidcontaminationmustbesuchthattheydonotaffectanymicroorganismsthataretoberevealedinthetest.Iftheproducttobeexaminedhasantimicrobialactivity,thisis,insofaraspossible,removedorneutralized.Ifinactivatorsareusedforthispurpose,theirefficacyandtheirabsenceoftoxicityformicroorganismsmustbedemonstrated.Ifsurface-activesubstancesareusedforsamplepreparation,theirabsenceoftoxicityformicroorganismsandtheircompati-bilitywithanyinactivatorsusedmustbedemonstrated.ENUMERATIONMETHODSUsetheMembraneFiltrationmethodoroneofthePlate-CountMethods,asdirected.TheMost-Probable-Number(MPN)Meth-odisgenerallytheleastaccuratemethodformicrobialcounts;however,forcertainproductgroupswithverylowbioburden,itmaybethemostappropriatemethod.6Pflug,I.J.SyllabusforanIntroductoryCourseintheMicrobiologyandEngineeringofSterilizationProcesses,4thed.St.Paul,MN:EnvironmentalSterilizationServices,1980.7Pflug,I.J.,andG.M.Smith.TheUseofBiologicalIndicatorsforMonitoringWet-HeatSterilizationProcesses,inSterilizationofMedicalProducts,ed.E.R.L.Gaugh-ranandK.Kereluk.NewBrunswick,NJ:JohnsonandJohnson,1977,193–230.8Holcomb,R.G.,andI.J.Pflug.TheSpearman-KarberMethodofAnalyzingQuantalAssayMicrobialDestructionData,inMicrobiologyandEngineeringSterilizationProcesses,ed.I.J.Pflug.St.Paul,MN:EnvironmentalSterilizationServices,1979.GeneralChapters106á55ñBiologicalIndicators—ResistancePerformanceTests/MicrobiologicalTestsUSP38OfficialfromMay1,2015Copyright(c)2015TheUnitedStatesPharmacopeialConvention.Allrightsreserved.Accessedfrom10.6.1.1bydevelopment7onThuMay0701:59:52EDT2015Thechoiceofamethodisbasedonfactorssuchasthenatureoftheproductandtherequiredlimitofmicroorganisms.Themethodchosenmustallowtestingofasufficientsamplesizetojudgecompliancewiththespecification.Thesuitabilityofthechosenmethodmustbeestablished.GROWTHPROMOTIONTEST,SUITABILITYOFTHECOUNTINGMETHODANDNEGATIVECONTROLSGeneralConsiderationsTheabilityofthetesttodetectmicroorganismsinthepresenceofproducttobetestedmustbeestablished.Suitabilitymustbeconfirmedifachangeintestingperformanceorachangeintheproductthatmayaffecttheoutcomeofthetest,isintroduced.PreparationofTestStrainsUsestandardizedstablesuspensionsofteststrainsorprepareasstatedbelow.Seed-lotculturemaintenancetechniques(seed-lotsystems)areusedsothattheviablemicroorganismsusedforinoculationarenotmorethanfivepassagesremovedfromtheoriginalmasterseed-lot.GroweachofthebacterialandfungalteststrainsseparatelyasdescribedinTable1.Table1.PreparationandUseofTestMicroorganismsGrowthPromotionSuitabilityofCountingMethodinthePresenceofProductMicroorganismPreparationofTestStrainTotalAerobicMicrobialCountTotalYeastsandMoldsCountTotalAerobicMicrobialCountTotalYeastsandMoldsCountStaphylococcusaureussuchasATCC6538,NCIMB9518,CIP4.83,orNBRC13276Soybean–CaseinDigestAgarorSoybean–CaseinDigestBroth30°–35°18–24hoursSoybean–CaseinDi-gestAgarandSoy-bean–CaseinDigestBroth£100cfu30°–35°£3daysSoybean–CaseinDi-gestAgar/MPNSoyb