SIMULTANEOUS LIPID AND CAROTENOID PRODUCTION BY STEPWISE FED-BATCH CULTIVATION OF Rhodotorula mucilaginosa WITH CRUDE GLYCEROL

Abstract In the present study, an innovative cultivation strategy of Rhodotorula mucilaginosa CCT 7688 to accumulate both lipids and high added value carotenoids was proposed, with the potential to contribute to the economic feasibility of microbial oils in comparison with vegetable oils. The stepwise fed-batch cultivation with crude glycerol feeding at 24 h, 96 h, and 144 h, with the addition of magnesium to the initial culture medium, resulted in a lipid content of 51.0 ± 0.3 % CDW, biomass concentration of 21.00 ± 0.48 g L-1, total lipid production of 10.72 ± 0.18 g L-1, lipid productivity of 0.037 ± 0.001 g L-1 h-1, volumetric carotenoid production of 2843.2 ± 282.0 μg L-1, and carotenoid productivity of 9.87 ± 0.98 μg L-1 h-1. These values represent a 6-fold increase in lipid content, a 19-fold increase in lipid production, and a 2-fold increase in carotenoid production compared to batch cultivation.