In order to investigate the effect of ammonia, C. curvatus was cultured with ammonium chloride at different concentrations,from 131 g N m3 to 3140 g N m3, and sodium nitrate
with the same nitrogen content was used as the control (Figs.1 and 2). Potassium acetate (33 kg m3) or glucose (20 kg m3)was used as the carbon substrates. The initial pH was 7.5.
After 60 h cultivation, the yeast cells were harvested.