FIG. 2.

Growth under denitrifying conditions of representatives of the five denitrifying organisms recovered in this study. (A) Growth curves, as measured by determining the optical density at 600 nm (OD₆₀₀), for each isolate. Lactate (10 mM) was used as the electron donor for Bacillus, Afipia, and Intrasporangium isolates. Acetate (10 mM) and ethanol (20 mM) were used for Rhodanobacter and Hyphomicrobium isolates, respectively. (B) Nitrate removal during growth of the five denitrifiers. Production of gaseous end products as a result of denitrification was demonstrated (Table 2).