Manipulation of Culture Conditions: Tool for Correlating/Improving Lipid and Carotenoid Production by Rhodotorula glutinis

Abstract

The coproduction of lipid and carotenoid by red yeasts in one cycle is more convenient and economical for the industrial sectors, while the kinetics correlation between both products under different culture conditions has been scarcely studied. This study is aiming to correlate the impact of different carbon sources, carbon to phosphorus ratio (C/P), temperature, aeration, pH, and metals on dry cell weight, lipid (GC and fluorescence microscope), and carotenoid (HPLC) production by Rhodotorula glutinis, and applying a novel feeding approach using a 5 L bioreactor to enhance carotenoid and unsaturated fatty acid production by R. glutinis. Whatever the culture condition is, the reversible correlation between lipid and carotenoid production was detected. Remarkably, when adding 0.1 mM BaCl2, cellular lipid was significantly increased 14% more than the control, with 79.3% unsaturated fatty acid (46% C18:2 and C18:3) and 50% γ-carotene, while adding 1 mM NiSO4, cellular carotenoid was enhanced around 53% than the control (torulene 88%) with 81% unsaturated fatty acid (61% oleic acid). Excitingly, 68.8 g/l biomass with 41% cellular lipid (79% unsaturated fatty acid) and 426 µgpigment/gdcw cellular carotenoid (29.3 mg/L) (71% torulene) were obtained, when the pH-temperature dual controlled process combined with metallo-sulfo-phospho-glucose feeding approach in the 5 L bioreactor during the accumulation phase was conducted. This is the first study on the kinetic correlation between lipid and carotenoid under different C/P ratio and the dual effect of different metals like NiSO4 on lipid and carotenoid production by red oleaginous yeasts, which in turn significant for enhancing the coproduction of lipid and carotenoid by R. glutinis.

Adaptation of Proteome and Metabolism in Different Haplotypes of Rhodosporidium toruloides during Cu(I) and Cu(II) Stress

“…In the publication of Elfeky et al, the biggest changes in the lipid profile of R. glutinis were observed when treated with 0.1 mM CuCl 2 , resulting in an increase in C16:0 from 13.2 to 26.4% as well as a decrease in C18:2 from 29.3 to 14.8%. Similar values were detected for 0.1 mM CuSO 4 [ 31 ]. These drastic shifts in fatty acid profiles were not observed in this study for either IFO0559 or IFO0880.…”

“…As several studies noted an increase in carotenoid content in Rhodotorula species when exposed to copper [ 27 , 29 , 30 , 31 ], the absorbance of extracted carotenoids was measured and normalized to DCW. All cultures exhibited an increase in carotenoid content over time.…”

Transcriptomic and Metabolomic Analyses Provide Insights into the Enhancement of Torulene and Torularhodin Production in Rhodotorula glutinis ZHK under Moderate Salt Conditions

“…In addition, previous study mentioned that the torulene and torularhodin production of R. glutinis was significantly increased after adding 1.0 mM NiSO 4 to the medium as compared to the control . The medium supplemented with 0.7 mM Al 2 (SO 4 ) 3 leads to a specific enhancement in torulene production of R.…”

Enhancing Red Yeast Biomass Yield and Lipid Biosynthesis by Using Waste Nitrogen Source by Glucose Fed-Batch at Low Temperature

“…Similarly, the biomass of R. gracilis ATCC 10788 was characterized by the highest intracellular lipid content (19 g/100 g d.w. ) after culture at 20 • C [52]. However, the intracellular lipid content as a function of different temperatures incubation was reversed for Rhodotorula glutinis, when the optimal 30 • C at day 6 resulted in 49.1% DW, 35.3 g/L, and 0.98 g/L/day, and the lower temperature of 25 • C decreased the lipid content significantly [53]. A similar correlation was also observed for Yarrowia lipolytica where a higher temperature of 33 • C led to reduced lipid yields [54].…”