Growth of A. pullulans in YPD. (A) OD₆₀₀ as a function of cell density (cells/ml) and fit with a linear regression (R² = 0.89). (B) OD₆₀₀ in liquid media was monitored at 10-min intervals. The standard curve in A was used to calculate cell densities of 5–10 × 10⁶ cells/ml (red box) and 2–4 × 10⁷ cells/ml (blue box). In both A and B, the mean is shown and error bars/gray shading represent the standard deviation across five experiments.