Pasteur effect is shown when you grow a facultatively anaerobic organism in an anaerobic condition. When you move that organism into an aerobic condition, you’ll get a result that the glucose consumption will get decreased compared to another organism which is not grown in an anerobic condition before.
This phenomenon happens because, in an anaerobic condition, the organism only need a little glucose to maintain the balance of NAD+/NADH, so when it’s moved into aerobic condition, this habit is still maintained for a while.