Assessment of the performance of a fed-batch cultivation from the preculture quality using an electronic nose

摘要

An electronic nose,a gas-phase multisensor system,was used to monitor precultivations of a recombinant tryptophan-producing Escherichia coli strain.The electronic nose signals showed a high correlation toward the main stages of the precultivations,namely,exponential growth,oxygen-limited growth,and glucose depletion.Principal component analysis (PCA) of the elctronic nose signals was performed and shown to be useful for monitoring preculture progression.More importantly,PCA also allowed a qualitative assessment of the preculture performance during subsequent fed-batch cultivations.The electronic nose signals from the precultures showed,furthermore,a high correlation to the time of phosphate limitation and the tryptophan yield coefficient of the subsequent fed-batch cultivations,which allowed an accurate predication of these process variables using partial least squares (PLS).The results demonstrate on data from 12 cultivations how the electronic nose can be s useful tool for the assessment of inoculum qualiy,thereby providing means of reducing batch-to-batch variation and increasing the productivity of bioprocesses.