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T Bley

Publications and source records attributed to T Bley.

23 records · Page 2Linked to original sources
PubMed1982

Yield coefficients in dependence on milieu conditions and cell states. III. Induction of synchrony in continuous yeast cell cultivation by milieu changes.

Induction of synchrony by various perturbations in continuous yeast cultivation on hydrocarbons of crude oil is described. Short-time temperature and pH-value shocks cause oscillations of budding cell percentage in the order of the cell cycle duration. An abrupt change of the phosphate ion concentration of the nutritional medium may also induce a synchronization of microbial growth. However, the frequency corresponds with the eigenfrequency of the fermentation process. The experimental values were investigated statistically using autocorrelation and spectral analysis.

Ascomycota↗
PubMed1981

Yield coefficients in dependence on milieu conditions and cell states. II. Influence of perturbations on continuous cultivation of the yeast Lodderomyces elongisporus on hydrocarbons.

The influence of perturbations on continuous yeast cell cultivations on hydrocarbons of crude oil is described. Due to such perturbations the fermentation system leaves its steady state, passes through transitional stages and reaches a new steady state. In the transitional stages a damped oscillation of biomass concentration, percentage of budding cells, oxygen consumption rate, and heat flow is observed. These results can be explained by partial synchronization of yeast cell functions in microorganism populations. In phases of partial synchronization the cell cycle of a single cell is reflected by the behaviour of the microorganism population. The adaptation of the carbon substrate feeding rate to the state of partially synchronized microorganism population makes possible lower specific substrate consumption in biomass production.

Aerobiosis↗
PubMed1979

[Effect of alternating milieu changes on specific substrate consumption in microorganisms].

In technical microbiology microorganisms often undergo alternating milieu changes. For instance, this is the case in recirculation reactors. The organisms react on these changes with an increase of entropy production and in connection with this with increasing substrate consumption. This increasing substrate consumption contradicts the aim of an optimum yield from a given substrate. Thus, studies of the reaction of microbial growth to alternating milieu changes are of great importance. A simple model of the influence of alternating milieu changes on specific substrate consumption is given. In it the biological conversion of substances is built up by an irreversible consecutive reaction. After preliminary examinations on the analogue computer the reaction of the model to alternating perturbations is simulated on the digital computer. The results of the stimulations are compared with experimental data. The good agreement of experiment and model justifies the use of the simple formulation in the preparation of technical processes.

Candida albicans↗