GLUCOSE-UPTAKE KINETICS OF SACCHAROMYCES-CEREVISIAE MONITORED WITH A NEWLY DEVELOPED FIA

The glucose content of the culture liquid during shift experiments and synchronized cultures of Saccharomyces cerevisiae H1022 (ATCC 32167) was monitored using a greatly improved and highly precise FIA. During shift-up experiments on the dilution rate, an overshoot of the glucose -concentration was observed. The amplitude of the overshoot showed a d ependency on the duration of undisturbed cultivation before applicatio n of the shift. Mutarotational non-equilibrium was excluded as the cau se of the observed overshoot. For the first time glucose measurements of oscillating cultures of Saccharomyces cerevisiae are demonstrated w ith high accuracy and reproducibility. The data strongly support the p roposals by Munch et al. (1992a,b) that faint oscillations in glucose concentration are responsible for the persistence of the synchronizati on. Analytical subsystems prove to be a powerful tool for investigatio n of the dynamics of metabolic pathways of microbial organisms. Accura te glucose measurements at low concentrations point out the limits and allow refinements of commonly used models.