Role of MMF1 Gene in Mannosylerythritol Lipid Secretion and Sustainable Biosurfactant Production from Brackish Water

• Author / Creator

  Xu, Yuze

• This thesis investigates the secretion of mannosylerythritol lipid (MEL) in the JCM10317 strain of P. antarctica, and the potential for a more cost-effective, environmentally friendly production process for MEL.
  The study demonstrates that the Pa MMF1 gene is necessary for the secretion of di-acylated MEL-A/B/C when utilizing water-soluble carbon sources, and also identifies an unknown species of MEL. In addition, the amount of MEL in the cellular fraction of the knockout strain is equal to or more than that of the wild-type strain. A MEL species shift towards more hydrophobic MEL-A was also observed in the cellular fraction of MMF1 KO groups. This is the first study to investigate the relationship between the MMF1 gene and MEL secretion in water-soluble carbon sources, providing new insights into the mechanisms of MEL secretion.
  In the brackish water production experiment, the findings demonstrate that the JCM10317 strain can ferment MEL with unsterilized brackish water as a production medium, with waste canola cooking oil as a carbon source. By using a waste product instead of a food crop, and was directly added to the fermentative medium without pre-treatment. Unsterilized brackish water was utilized for MEL production with the addition of sodium chloride (NaCl). This process can convert a waste product into a value-added product, eliminate the need for sterilization, save energy costs, and reduce the need for specialized infrastructure, further contributing to sustainability efforts.
  Overall, the findings of this thesis provide insights into the mechanisms of MEL secretion in P. antarctica and highlight the potential application of using unsterilized brackish water as a production medium in bioproduction. Further research is needed to fully understand the mechanism of MEL secretion and the impact of brackish water and waste cooking oil on the MEL production process and the quality of the final product.

• Subjects / Keywords

  • mannosylerythritol lipid (MEL)
  • Pseudozyma antarctica
  • secretion
  • brackish water
  • waste cooking oil
  • bioproduction

• Graduation date

  Fall 2023

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-5s8x-3h20

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.