Since carotenoids are synthesized inside the cell, it is desirable to find an efficient method to extract carotegenic pigments. This study aimed at comparing the effectiveness of different chemical and mechanical techniques to disrupt the cell wall of Sporidiobolus pararoseus and Rhodotorula mucilaginosa yeasts isolated from environmental samples. Among the techniques under study, the ultrasonic bath and the abrasion with glass beads yielded the most promising results for S. pararoseus (84.8 ± 2.3 and 76.9 ± 2.1 μg/g, respectively). The ultrasonic bath yielded the highest specific concentration of carotenoids for R. mucilaginosa (193.5 ± 25.8 μg/g), while the biomass freezing process improved neither the extractability nor the specific concentration of carotenoids. Lyophilization increased the specific concentrations of carotenoids from S. pararoseus and R. mucilaginosa by 20 and 13.7%, respectively, while the freezing process did not significantly affect (p > 0.05) the recovery of carotenoids from both yeasts; thus, it may be eliminated from the process.
Keywords: Biomass; Carotenoids; Freezing; Ultrasonic bath; Yeast.