A mechanism-assisted data-driven model to improve the efficiency of
sophorolipids by Candida bombicola
Abstract
In this study, we developed a mechanism-assisted data-driven model to
regulate substrate feedback to improve the production efficiency of
sophorolipids (SLs). First, we used a variety of on-line biosensors to
establish a multi-scale parameter detection system. We found that the
production of SLs by fed-batch fermentation could be divided into three
stages: a stage that was limited by cell production capacity, a stage
that was inhibited by high product concentration, and a stage that was
limited by oxygen supply. Subsequently, we used process parameters to
develop a data-driven model, and this was then combined with the
analysis of cell metabolic mechanisms. The optimal production of SLs was
achieved in the first and second stages by the precise feedback
regulation of substrate feeding, which increased the titer of SLs by
4.9%. The control error of the substrate was reduced from more than
15% to less than 5%. The mechanism-assisted data-driven model was then
applied for semi-continuous fermentation during the production of SLs.
This effectively alleviated the oxygen limitation during the third
stage, and further increased the productivity of SLs to 2.30 g/L/h,
40.2% higher than the fed-batch fermentation method.