APPLICATION OF SCANNING FLUOROMETRY FOR MONITORING OF A FERMENTATION PROCESS

Conventional observation of a fermentation process by using NAD(P)H-de pendent fluorescence provides a mean for cell monitoring, but its prac tical application has been very limited due to many factors that affec t culture fluorescence. In this work we studied correlation of scannin g fluorometry signals with various process variables and with cell met abolic states and showed that scanning fluorometry is more informative than conventional NAD(P)H-dependent fluorescence. A stepwise multiple -regression procedure has been used to select meaningful signals from the whole spectrum, and we found that with three or four components of the excitation-emission plane the process variables can be portrayed with a rather good accuracy. The approach is demonstrated on the examp les of wild-type or recombinant Escherichia coli and Saccharomyces cer evisiae fermentations.