FIG. 3.

Controls for cell integrity and viability during anaerobic fermentation of maltose by cells harvested from aerobic, maltose-limited chemostat cultures of S. cerevisiae CEN.PK113-7D. (A) Extracellular protein concentrations and fraction of viable cells as determined from plate counts. The values are averages ± mean deviations for two experiments performed with cells from independent chemostat cultures. (B) Extracellular maltase activity, plotted as glucose concentration during incubation of supernatant samples taken at different times during anaerobic fermentation experiments. Symbols: ○, zero-time supernatant; •, 30-min supernatant; □, 60-min supernatant; ▪, maltose control (100 g · liter⁻¹), revealing contamination of commercially available maltose with glucose. The values are averages ± mean deviations for two experiments performed with cells from independent chemostat cultures.