Supplementary data Efficient sophorolipids production via a novel in situ separation technology by Starmerella bombicola Zhaopeng Liu a , Xiwei Tian a, *, Yang Chen a , Yumeng Lin a , Ali Mohsin a , Ju Chu a, * a State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China * Corresponding author: Tel: +86-21-64253021, Fax: +86-21- 64253702 E-mail address: [email protected] (Xiwei Tian), [email protected] (Ju Chu) Address: P.O. box 329, 130 Meilong Road, State Key Laboratory of Bioreactor Engineering, East China University
Transcript
Supplementary data
Efficient sophorolipids production via a novel in situ separation technology by Starmerella bombicola
Zhaopeng Liua, Xiwei Tiana,*, Yang Chena, Yumeng Lina, Ali Mohsina, Ju Chua,*
a State Key Laboratory of Bioreactor Engineering, East China University of Science
Address: P.O. box 329, 130 Meilong Road, State Key Laboratory of Bioreactor
Engineering, East China University of Science & Technology, Shanghai 200237, P. R.
China
Fig. S1. Pictures of broth sample. Broth sample was taken at 83 h in fermentation 1 and
its microscopic image (a) was taken instantly at 1000x by SUNNY BMDH200
microscopy. After standing for 1 min in measuring cylinder, an image (b) was taken.
The oil/SLs ratio was between 0.015-0.020.
Fig. S2. HPLC analysis of SLs components in samples from fermentation 1 and 2. Six
peaks on chromatogram was identified with standards (Sigma). Error bars represent
standard deviations of triplicate tests.
Fig. S3. The effect of SLs content on frothing. SLs content in tube 1-5 was respectively
139 g/L, 111 g/L, 83 g/L, 56g/L and 28 g/L. Oil of the same ratio (about 0.100) to SLs
was added to each tube. This photo was taken in 1 min after 5 tubes were shaken
vigorously.
Fig. S4. Effect of standing time on cell growth. Broth sample at146 h from fermentation
2 was used as inoculum for fresh medium in 500 mL flask. And the broth was let stand
for 0 min, 20 min, 40 min and 60 min, respectively, before inoculation. Cell
proliferation multiple was calculated as Eq. A.1. Error bars represent standard
deviations of triplicate tests.
Fig. S5. Feeding strategies of Glc and oil in fermentation 1 and 2. Black represents
fermentation 1 and red represents fermentation 2. Triangle represents Glc and square
represents rapeseed oil.
Equations
Area percent of each peak (%) = An /AT*100 (S1)
where An and AT represent the peak area of each SLs peak on chromatograph and the
total area of all SLs peaks, respectively.
Gas hold up (%) = Hf /Hp*100 (S2)
where Hf and Hp (mm) represent the froth height of the samples in 50 mL measuring
cylinder and the height of crude SLs layer after complete precipitation of the froth,
respectively.
SLs recovery (%) = WSLs-f /WSLs-b *100 (S3)
where WSLs-f and WSLs-b (g) represent the weight of the SLs in the separated froth and in
the broth before each-round separation, respectively.
Glc recovery (%) = Glcup /Glcf *100 (S4)
where Glcup and Glcf (g) represent the total glucose in the upper water layer during cell
recovery and in the separated froth, respectively.
Equation for power number (as below) is used to compare the mixing power input
between fermentation 1 and 2. In both fermentations, density is assumed to be constant
as the existence of oil and SLs leaves little effect on broth density. Considering the
identical fermenter, stirring diameter is also identical between them. Additionally, the
power number is commonly constant in turbulent regime. Therefore, stirring speed is
the major variable and has an cubic effect on the mixing power input [1].
P = Npρn3D5 (S5)
Where P is power, Np is power number, ρ is density, n is stirrer speed and D is stirrer
diameter.
Reference
[1] B.M. Dolman, C. Kaisermann, P.J. Martin, J.B. Winterburn, Integrated sophorolipid production and gravity separation, Process Biochem. 54 (2017) 162-171.
