You are growing Bacillus subtilis in a bioreactor and notice that the growth rate has slowed and the pH has decreased. What could you add?
A) glucose
B) lactic acid
C) lactose
D) oxygen
E) peptides

Question

Quizplus · Accepted Answer

The decrease in pH suggests that the culture may be undergoing anaerobic fermentation, producing acidic byproducts. Adding oxygen can help shift the metabolism back to aerobic respiration, improving growth rate and stabilizing pH.

You Are Growing Bacillus Subtilis in a Bioreactor and Notice