Engineering Rhodotorula toruloides as a platform organism for de novo synthesis of fatty-acid esters.

Summary

The authors reprogrammed R. toruloides to de novo produce multiple fatty-acid ester classes, reaching 13.04 g/L wax esters in a 5 L fermenter without exogenous alcohols or lipids. The platform provides a scalable, sustainable route to cosmetic emollients and other oleochemicals.

Key Findings

• De novo biosynthesis of diverse fatty-acid esters in R. toruloides without exogenous alcohol/lipid precursors
• Achieved titers: FAEEs 579 mg/L, FASBEs 169 mg/L, and wax esters 1.30 g/L in shake flasks
• Scaled production of wax esters to 13.04 g/L in a 5 L fermenter via pathway and process optimization

Clinical Implications

While not clinical, this platform could shift cosmetic formulations toward bio-based emollients with reduced environmental footprint and greater supply stability, influencing ingredient selection and sustainability commitments in dermatologic products.

Limitations

• No assessment of downstream purification economics or life-cycle environmental impact
• Product safety/quality for cosmetic-grade applications not evaluated in this study

Future Directions

Pilot-scale technoeconomic and LCA analyses; pathway tuning for ester profile customization; safety/quality validation for cosmetic-grade emulsions and emollients.