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Penicillin:thefirstmiracledrug
Manyofyouarehereonlybecausepenicillinsavedyourlife,orthelifeofoneofyourparentsorgrandparents.Penicillin'sabilitytocurepeopleofmanyonce-fatalbacterialinfectionshassavedsomanylivesthatitiseasytounderstandwhyitwasoncecalleda"miracledrug".
Antibioticsarechemicals,effectiveatverylowconcentrations,createdaspartofthelifeprocessofoneorganism,whichcankillorstopthegrowthofadisease-causingmicrobe--agerm.In1929,AlexanderFleming,adoctorandresearcheratSt.Mary'sHospitalinLondon,England,publishedapaperonachemicalhecalled"penicillin",whichhehadisolatedfromfromamold,Penicilliumnotatum.Penicillin,Flemingwrote,hadpreventedthegrowthofaneighboringcolonyofgermsinthesamepetridish.Dr.Flemingwasneverabletopurifyhissamplesofpenicillin,buthebecamethefirstpersontopublishthenewsofitsgerm-killingpower.HowardFlorey,ErnstChainandNormanHeatleyexpandedonFleming'sworkin1938,atOxfordUniversity.Theyandtheirstaffdevelopedmethodsforgrowing,extractingandpurifyingenoughpenicillintoproveitsvalueasadrug.
WorldWarII(1939-1945)hadbegunbythetimetheirresearchwasshowingresults.ThemainresearchandproductionwasmovedtotheUnitedStatesin1941,toprotectitfromthebombspoundingEngland.Workbeganonhowtogrowthemoldefficientlytomakepenicillininthelargequantitiesthatwouldbeneededforthousandsofsoldiers.Asthedestructionofthewargrew,sodidinterestinpenicillininlaboratories,universitiesanddrugcompaniesonbothsidesoftheAtlantic.Thescientistsknewtheywereinaraceagainstdeath,becauseaninfectionwasaslikelytokillawoundedsoldierashiswound.
Creatingtherightenvironmentforgrowthwasthefirststepinproducingenoughpenicillintobeusedasadrug.InOxford,experimentsshowedthatPenicilliumnotatumgrewbestinsmallshallowcontainersonabrothofnutrients.Penicilliumneedlotsofair.IntheUnitedStates,itwasdiscoveredthathuge"deepfermentation"tankscouldbeusedifsterilizedairwaspumpedcontinuallythroughthetanks.Productionincreasedevenmorewhencornsteepliquor,athick,stickyby-productofcornprocessing,wasaddedtothetanks.Cornsteepliquorcontainedconce
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2024-09-19
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