I am trying to grow Bifidobacterium longum in a anaerobic reactor. I use MRS+ L-cysteine for the growth media (which is also regular growth media). I maintain anaerobic conditions with N2 sparging. However, I realized that my bacteria do not grow, but grow if I do not sparge N2. I use redox probe to monitor. Redox stays around -200 mV when no growth. When growth with one time N2 sparging in the begining it ended up with 10mV. I have seen Bifidobacteria is very difficult to grow when exposed to O2. So, I dont understand what is happening and why continuous N2 all the time inhibit the growth? Does anybody have an idea?
Thank you!!