TY - JOUR
T1 - Efficient in-situ separation design for long-term sophorolipids fermentation with high productivity
AU - Wang, Huaimin
AU - Kaur, Guneet
AU - To, Ming Ho
AU - Roelants, Sophie L.K.W.
AU - Patria, Raffel Dharma
AU - Soetaert, Wim
AU - Lin, Carol Sze Ki
N1 - Funding Information:
This project is fully funded by the Applied Research Grant of City University of Hong Kong (Project No. of 9667156).
Funding Information:
This project is fully funded by the Applied Research Grant of City University of Hong Kong (Project No. of 9667156 ). Appendix A
PY - 2020/2/10
Y1 - 2020/2/10
N2 - Until now, the production of microbial biosurfactants has been limited to the use of first-generation (food) substrates. Moreover, the results on sophorolipids yield and productivity reported by state-of-the-art fed-batch processes for sophorolipids production remain unsatisfactory and lead to a significantly high cost per kg of the product. With an aim to address these problems, this study demonstrates a long-term and high-efficiency sophorolipids production method using a semi-continuous integrated production-separation system which utilizes food waste as a substrate. An average volumetric productivity of 2.43 g L−1 h −1 and the overall sophorolipids yield on the substrate (i.e. the combination of glucose and oleic acid as carbon source) of 0.73 g g−1 was achieved within 240 h by fed-batch and separation fermentation. Moreover, the potential of sustaining high production efficiency during long-term fermentation times (480 h) was investigated. No reduction in process efficiency was observed, i.e. average volumetric productivity and an overall sophorolipids yield of 2.39 g L−1 h −1 and 0.73 g g−1 were obtained, respectively. Notably, a very high biomass concentration of 117.2 g L−1 was observed in fed-batch fermentation and separation, which is the highest cell density ever reported for Starmerella bombicola. The separation efficiency was also calculated to evaluate the in-situ separation performance of the developed process quantitatively. In 480-h fermentation, the average separation efficiency of 74.3% and overall separation efficiency of 93.0% was achieved after six separation cycles, suggesting that both separation design and process control were successful in laboratory-scale fermentation. These findings demonstrate the potential of the developed sophorolipids fermentation-separation system for application at industrial scale.
AB - Until now, the production of microbial biosurfactants has been limited to the use of first-generation (food) substrates. Moreover, the results on sophorolipids yield and productivity reported by state-of-the-art fed-batch processes for sophorolipids production remain unsatisfactory and lead to a significantly high cost per kg of the product. With an aim to address these problems, this study demonstrates a long-term and high-efficiency sophorolipids production method using a semi-continuous integrated production-separation system which utilizes food waste as a substrate. An average volumetric productivity of 2.43 g L−1 h −1 and the overall sophorolipids yield on the substrate (i.e. the combination of glucose and oleic acid as carbon source) of 0.73 g g−1 was achieved within 240 h by fed-batch and separation fermentation. Moreover, the potential of sustaining high production efficiency during long-term fermentation times (480 h) was investigated. No reduction in process efficiency was observed, i.e. average volumetric productivity and an overall sophorolipids yield of 2.39 g L−1 h −1 and 0.73 g g−1 were obtained, respectively. Notably, a very high biomass concentration of 117.2 g L−1 was observed in fed-batch fermentation and separation, which is the highest cell density ever reported for Starmerella bombicola. The separation efficiency was also calculated to evaluate the in-situ separation performance of the developed process quantitatively. In 480-h fermentation, the average separation efficiency of 74.3% and overall separation efficiency of 93.0% was achieved after six separation cycles, suggesting that both separation design and process control were successful in laboratory-scale fermentation. These findings demonstrate the potential of the developed sophorolipids fermentation-separation system for application at industrial scale.
KW - Food waste
KW - Fractionation
KW - High volumetric productivity
KW - Lactonic sophorolipids
KW - Separation efficiency
UR - http://www.scopus.com/inward/record.url?scp=85074390353&partnerID=8YFLogxK
U2 - 10.1016/j.jclepro.2019.118995
DO - 10.1016/j.jclepro.2019.118995
M3 - Journal article
AN - SCOPUS:85074390353
SN - 0959-6526
VL - 246
JO - Journal of Cleaner Production
JF - Journal of Cleaner Production
M1 - 118995
ER -