Fermentomics : a real-time metabolomics approach for the enhanced production of biosurfactants

Microbial biosurfactants are currently emerging as fully bio-based and renewable alternatives to traditional petroleum-based surfactants. The yeast Starmerella bombicola is a known producer of glycolipid surfactants and through genetic engineering, the portfolio of biosurfactants has been expanded towards new innovative compounds such as the bolaform sophorosides. Despite their interesting properties and potential applications, the low productivities of their biosyntheses currently do not allow the process to be economically viable. In this work, the bottlenecks leading to low productivities will be tackled through bioprocess development. Typically such bioprocess development is combined with targeted and off-line analyses of substrates and bioproducts. However, these analyses do not provide any information about unknown underlying biochemical ‘marker’ pathways/metabolites influencing biosurfactant production. Additionally, the off-line and delayed follow-up often results in measures not taken timely. Therefore, a metabolomics approach to monitor the fermentation in real-time will be set up in parallel to the bioprocess development. The metabolic fingerprint of fermentations will be monitored by using an untargeted automated laser-assisted rapid evaporative ionisation mass spectrometry (LA-REIMS) platform and correlated to the bioprocess efficiency. This metabolomics approach, reflective of the complex interplay between microbial kinetics and dynamic environmental changes in bioreactors, will speed up bioprocess development. Moreover, a successful at-line metabolomics approach would be a powerful tool in the monitoring of (industrial) fermentations.