THE GROWTH OF BACTERIA IN A CONTINUOUS FLOW OF BROTH

Abstract

Cultures of Streptococcus lactis or Escherichia coli, in flasks through which broth was flowed slowly, maintained a constant population level as long as the exp. was continued. Under similar conditions Strep. lactis and E. coli grew together, each one maintaining a high population. At the beginning, there was an apparent inhibition of Strep. lactis and, later, a distinct falling off in the number of E. coli. In a culture flask with a continuous flow of fresh broth into the flask, and with the overflow removed by filtration so that there was no emigration of cells out of the flask, Strep. lactis maintained a constant population level. Under laboratory conditions a continuous lactic fermentation could be maintained indefinitely by providing a continuous supply of sterile lactose broth. Under favor-able conditions an 800-cc. culture delivered every 24 hrs. 500-900 cc. of effluent from which practically all the sugar had been fermented.