Download the full-sized PDF of Development of technological alternatives to produce renewable fuels  from oleaginous microorganismsDownload the full-sized PDF



Permanent link (DOI):


Export to: EndNote  |  Zotero  |  Mendeley


This file is in the following communities:

Graduate Studies and Research, Faculty of


This file is in the following collections:

Theses and Dissertations

Development of technological alternatives to produce renewable fuels from oleaginous microorganisms Open Access


Other title
Alternative, renewable fuels
Heterotrophic microalgae
Type of item
Degree grantor
University of Alberta
Author or creator
Espinosa Gonzalez, Maria I
Supervisor and department
Bressler, David C (Agricultural, Food and Nutritional Science)
Examining committee member and department
Rehmann, Lars (Department of Chemical and Biochemical Engineering, University of Western Ontario)
McMullen, Lynn (Agricultural, Food and Nutritional Science)
El-Din, Mohamed Gamal (Civil and Environmental Engineering)
Kav, Kat (Agricultural, Food and Nutritional Science)
Department of Agricultural, Food, and Nutritional Science
Bioresource Technology
Date accepted
Graduation date
Doctor of Philosophy
Degree level
Microbial lipids are a promising feedstock for the production of renewable fuels. However, use of microbial lipids has been hindered due to challenges in the cultivating and processing of microbes. Thus, innovative technologies are required to enhance the feasibility of integrating oleaginous microorganisms into biofuel production strategies. Development of such technologies is the primary goal of this thesis. Slurries of oleaginous microbial biomasses (microalgae Chlorella protothecoides and yeast Cryptococcus curvatus) were thermally hydrolyzed under subcritical conditions. Hydrolysis products including fatty acids, aqueous byproduct streams, and insolubles, were separated and characterized. Fatty acids were subsequently pyrolyzed to yield renewable fuels. Microalgae and yeast were also cultured in aqueous byproduct streams from the hydrothermal processing of fats, oils, and oleaginous biomasses. Both model microorganisms used the glycerol byproduct from hydrolysis of fats and oils as a carbon source and displayed growth and lipid accumulation comparable to or better than cultures grown in pure glycerol. Similarly, supplementation of microbial cultures with microbial aqueous byproduct streams promoted higher biomass production compared to non-supplemented cultures. Finally, microalgae was grown using whey permeate, a byproduct from the cheese industry. Pre-hydrolyzed whey promoted heterotrophic growth of this microalgae in both batch and fed-batch modes. Furthermore, whey permeate could be consumed by microalgae using simultaneous saccharification and fermentation. The technologies for producing and using oleaginous biomasses proposed in this research reduce processing steps and valorize industrial waste streams. They also generate a suitable feedstock for renewable fuel production and a nutrient-rich supplement for microbial cultivation.
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication
Espinosa-Gonzalez I., et al. (2014) Bioresource Technology (158).Espinosa-Gonzalez I., et al. (2013). Bioresource Technology (155)Espinosa-Gonzalez I., et al. (2014) Journal of Biotechnology (187)Espinosa-Gonzalez I.,(2014) Bioresource Technology. DOI: 10.1016/j.biortech.2014.08.006.

File Details

Date Uploaded
Date Modified
Audit Status
Audits have not yet been run on this file.
File format: pdf (PDF/A)
Mime type: application/pdf
File size: 3142931
Last modified: 2015:10:12 11:39:01-06:00
Filename: EspinosaGonzalez_Maria_I_201409_PhD.pdf
Original checksum: d01930b57969951fd5edf24b112310d8
Activity of users you follow
User Activity Date