Protectants used in the cryopreservation of microorganisms

ReviewProtectantsusedinthecryopreservationofmicroorganismsqZdenekHub�aalek*MedicalZoologyLaboratory,InstituteofVertebrateBiology,AcademyofSciences,Kl�aa�sstern�ıı2,CZ-69142Valtice,CzechRepublicReceived7October2002;accepted7May2003AbstractThecryoprotectiveadditives(CPAs)usedinthefrozenstorageofmicroorganisms(viruses,bacteria,fungi,algae,andprotozoa)includeavarietyofsimpleandmorecomplexchemicalcompounds,butonlyafewofthemhavebeenusedwidelyandwithsatisfactoryresults:theseincludedimethylsulfoxide(Me2SO),glycerol,bloodserumorserumalbumin,skimmedmilk,peptone,yeastextract,saccharose,glucose,methanol,polyvinylpyrrolidone(PVP),sorbitol,andmaltextract.PairwisecomparisonsofthecryoprotectiveactivityofthemorecommonCPAsusedincryomicro-biology,basedonpublishedexperimentalreports,indicatethatthemostsuccessfulCPAshavebeenMe2SO,methanol,ethyleneglycol,propyleneglycol,andserumorserumalbumin,whileglycerol,polyethyleneglycol,PVP,andsucrosearelesssuccessful,andothersugars,dextran,hydroxyethylstarch,sorbitol