ENZYMATIC MULTI-CHANNEL-FIA METHODS FOR ONLINE FERMENTATION MONITORING AND CONTROL

Abstract

A multichannel FIA system with high reliability and flexibility was developed for on-line process monitoring and control of fed batch and continuous fermentations. Glucose, L-Lactate, D-a and L-a-Hydroxybutyric acid(D- und LHBS), Isoleucin, Leucin, Ethanol, Acetaldehyde and Ammonia are enzymatically determined with fluorimetric detection. For all assays dehydrogenases alone or coupled with a second enzyme are immobilized in packed bed tube reactors. In the proposed parallel configuration of enzyme reactors only one detector is necessary. In a miniaturized and modular on-line sampling system the sample solution is diluted, conditioned and purified from interfering substances. The proposed FIA set up allows the adaptation of the different analyte concentrations to the ranges of the corresponding enzymatic assays. A freely programmable valve configuration guarantees a high flexibility in solving different problems of process analysis. The whole FIA-equipmentis controlled by an user friendly software running on a personal computer.The process analytical regime consists of on-line analysis, calibration- and recalibration cycles. The control of these cycles, the detctor signal evaluation and the calculation of the analytical results are implemented fully automatic.