Improvement of selenium enrichment in Rhodotorula glutinis X-20 through combining process optimization and selenium transport

Figures & data

Table 1. HG-AFS conditions.

High negative voltage of PMT (V)	340
Atomizer height (mm)	8
Lamp current (mA)	100
Se-HCL, wavelength (nm)	196
Flow rate of carrier gas (argon) (mL·min^−1)	400
Flow rate of shield gas (argon) (mL·min^−1)	800
Flow of reducing solution (NaBH4) (mL·min^−1)	4
Read method	Peak high
Read time (s)	6

Figure 1. Influence of pH (a) and temperature (b) on the biomass and selenium content of R. glutinis X-20.

Figure 2. Influence of fermentation time on the biomass and selenium content of R. glutinis X-20.

Figure 3. Influence of the volume of liquid on the biomass and selenium accumulation of R. glutinis X-20.

Figure 4. Transcriptional analysis of Pho84, Pho89, Pho87 and Pho90.

Figure 5. Effects of phosphorus transporter on selenium accumulation in R. glutinis X-20.

Table 2. Selenium-enriched performance in various yeasts.

Strain	Selenium content (µg/g)	Methods	Reference
R. glutinis X-20	5349.6	Regulating selenium transport and using mixed carbon culture	This study
S. cerevisiae YR166	2608.7	60 Co ץ-ray irradiation methods	[27]
S. cerevisiae	2452	Mutagenesis	[39]
S. cerevisiae	1400	Optimization of cultivation conditions	[15]
S. cerevisiae ATCC MYA-2200 + C. utilis ATCC 9950	5470	Adding sodium selenite salts of different concentrations	[10]
C. utilis CCTCC M 209298	1080	Acid stress	[40]

Figure 6. The effect of mixed carbon source on the biomass and selenium accumulation of R. glutinis X-20.

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