Factors Affecting the Viability of Serratia marcescens During Dehydration and Storage

Abstract

Cells from 18- and 24-hr. aerated cultures proved most resistant to drying. When dried in vacuum in the presence of P2O5 (Stamp''s method) and subsequently stored in air over P2O5, the organisms were protected to large extent by ascorbic acid and marmite (a yeast product) . With lyophilization, maximum survival was achieved in the presence of dextrin, ascorbic acid, thiourea and NH4Cl in conc. of 2, 0.5, 0.5, 0.5%, respectively, at pH 6-7. Viability was practically unchanged when lyophilized S. marcescens was stored under high vacuum, but was greatly reduced in storage under air or N2.