Biotechnology and Bioengineering: Volume 119, Number 4, April 2022

Biotechnology and Bioengineering

A mathematical model is presented for both batch and continuous cultures of microorganisms utilizing inhibitory substrates. The key feature of the model is the use of a inhibition function to relate substrate concentration and specific growth rate. Simulation studies show that the primary result of inhibition by substrate in a batch culture is an increase in the lag time whereas in continuous c...

Basic and Clinical Neuroscience, Volume 4, Number 4, Full Text

Biotechnology and Bioengineering

Partially purified glucoamylase from Aspergillus awamori NRRL 3112 was immobilized on diethylaminoethyl cellulose in the presence of low ionic-strength acetate buffers at pH 4.2. The active enzyme-cellulose complex was used to convert starch substrates continuously to glucose in stirred reactors. Substrate concentrations as high as 30% could be quantitatively converted to glucose at a rate of m...

Biotechnology and Bioengineering

The steady state, nonlinear diffusion equations which describe reactions in constrained enzyme solutions are of great interest in many biological and engineering applications. As in other types of nonlinear differential equations, exact analytical solutions do not exist except in some simplified cases. In this paper, a general procedure is presented for solving numerically for the substrate con...

Biotechnology and Bioengineering

The concept of a “critical oxygen concentration” is conventionally considered to hold for the submerged aerobic fermentation of glucose to gluconic acid. Above the critical level the fermentation rate is supposedly independent of oxygen concentration. In this work it is shown that, at a given agitation rate, the fermentation is independent of dissolved oxygen when above the critical. However, a...