Exploring the genetic expression of Wickerhamomyces anomalus during biosurfactant production from waste cooking oil

Aims: Biosurfactants are valuable eco-friendly compounds with broad industrial applications, particularly when produced sustainably using yeast and renewable carbon sources. Despite the potential of yeast in biosurfactant synthesis, little is known about the specific gene expression changes underlying this process. This study investigates the genetic response of Wickerhamomyces anomalus CCMA 0358 to biosurfactant production using waste cooking oil (WCO) as a low-cost carbon source. Methods and results: During a 0-12 h fermentation period, RNA (ribonucleic acid) sequencing revealed 829 differentially expressed genes in W. anomalus grown with WCO, suggesting targeted metabolic adaptations. Pathway analysis showed WCO's significant impact on glycolysis, gluconeogenesis, and lipid biosynthesis. Gene ontology annotations further indicated adaptive responses in ribosome biogenesis and lipid metabolism, which are crucial for the efficient utilization of WCO. Notably, WCO induced the upregulation of very-long-chain fatty acid precursors and adjustments in glycolytic enzyme expression, both essential for biosurfactant production. Conclusions: This study reveals, for the first time, the specific genetic pathways and metabolic adjustments that W. anomalus employs to produce biosurfactants from WCO. The increased expression of lipid metabolism enzymes and cell membrane components highlights a tailored adaptive mechanism for lipid-rich waste substrates, positioning W. anomalus as a promising candidate for sustainable biosurfactant production.