Figure 2. The majority of ammonium is not consumed remaining in the medium during culture aging.

Ammonium consumption (NH₄)₂SO₄ by S. cerevisiae BY4742 cultured in SD media buffered to: pH 3.4 (A and C) or pH 6.0 (B and D), with 2% (A and B) or 0.5% (C and D) glucose and supplemented with: (◆) high and (●) low concentrations of auxotrophy-complementing amino acids. Day -3 represents the day of culture inoculation and day zero represents the beginning of aging experiments. Values are means ± SEM (n=3).