Carotenoid extraction from Phaffia rhodozyma biomass: downstream strategies and economic evaluation of energy

This study aimed at investigating the technique of cell disruption by dimethylsulfoxide (DMSO) and different thermal pretreatments of yeast-biomass (Phaffia rhodozyma) to reach effective carotenoid extraction. Thus, the extraction procedure, color properties, antioxidant activity and global energy consumption (GEC) were evaluated. The most effective carotenoid extraction was carried out by the adapted acetone procedure (3 repetitions), which reached 185.56 µg g−1 and 1334.45 µg L−1 of specific and volumetric carotenoids, respectively. Different thermal treatments were used in the downstream steps to evaluate carotenoid extraction after cell disruption by DMSO. Pretreatment lyophilization showed total difference in color (∆E*), which was about 35.97 by comparison with other pretreatments that improved biomass redness/yellowness and reached about 59. The freeze-drying (24/24 h) pretreatment of biomass was the best process since it led to increase of 12.4% in carotenoid extraction, besides increase of 26, 26.1 and 50% in ABTS, DPPH and FRAP antioxidant activity, respectively, by comparison with the standard. Regarding the economic evaluation of energy, the adapted process was considered 36.8% more cost-effective than the standard one. Thus, changes made in the extraction process of carotenoids from Phaffia rhodozyma biomass enabled high recovery of carotenoids with high antioxidant potential. As a result, they present potential to be applied in food and pharmaceutical industries.