Spore Formation by Bacillus subtilis in Peptone Solutions Altered by Treatment with Activated Charcoal

Abstract

A factor which limits spore formation of B. subtilis can be removed from Bacto and Parke Davis peptone solns. by treatment with activated charcoal. Adsorption can be achieved most readily in the pH range 3-5. Sporulation in charcoal-treated peptone water is not influenced by conc. of total nutrients as estimated by Kjeldahl N, whereas in untreated bacto-peptone water the % of cells as spores after 72 hrs.'' incubation bears an inverse relationship to peptone conc. After treatment with charcoal, peptone water supports very nearly if not as many vegetative cells per ml. as untreated peptone water of equivalent total N content.