A look into Phaffia rhodozyma biorefinery: From the recovery and fractionation of carotenoids, lipids and proteins to the sustainable manufacturing of biologically active bioplastics

Carotenoids over-producing yeast has become a focus of interest of the biorefineries, in which the integration of the bioproduction with the following downstream processing units for the recovery and purification of carot-enoids and other value-added byproducts is crucial to improve the sustainability and profitability of the overall bioprocess. Aiming the future implementation of Phaffia rhodozyma-based biorefineries, in this work, an inte-grative process for fractionation of intracellular compounds from P. rhodozyma biomass using non-hazardous bio-based solvents was developed. After one-extraction step, the total amount of astaxanthin, beta-carotene, lipids and proteins recovered was 63.11 mu g/gDCW, 42.81 mu g/gDCW, 53.75 mg/gDCW and 10.93 mg/g, respectively. The implementation of sequential back-extraction processes and integration with saponification and precipitation operations allowed the efficient fractionation and recovery (% w/w) of astaxanthin (-72.5 %), beta-carotene-90.17 %), proteins (21.04 %) and lipids (23.72 %). After fractionation, the manufacture of carotenoids-based products was demonstrated, through the mixture of carotenoids-rich extracts with bacterial cellulose to obtain biologically active bioplastics.

Automated summary

A process using bio-based solvents was developed for the fractionation and recovery of compounds from red yeast, achieving efficient separation and recovery of astaxanthin, beta-carotene, proteins, and lipids. Furthermore, biologically active bioplastics were produced by mixing carotenoid-rich extracts with bacterial cellulose.