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

Some years ago it was found that Bacillus subtilis sporulated more profusely in Bacto-peptone broth when a small quantity of activated charcoal was added to the medium. Further studies revealed that although the charcoal was removed from the medium prior to inoculation, the percentage of cells sporulating during short incubation periods was still appreciably greater than in untreated Bacto-peptone broth. The work subsequently done to determine the nature of the response of B. subtilis to charcoal treatment is the subject of the present report. Although the investigations are not completed, publication of the available data seems advisable since it is improbable that further work will be possible in the near future. Apparently the influence on sporulation of various fractions of commercial peptones has not previously been studied.