Bacteriophages as antimicrobial agents against bacterial contaminants in yeast fermentation processes

• Author / Creator

  Bertozzi Silva, Juliano

• Bacterial contaminants are ubiquitous in yeast fermentation processes for biofuel production. In general, they compete with yeasts for nutrients, reducing overall production yield. The present project investigates the application of bacteriophages (phages), viruses infecting and killing prokaryotes, as potential antibacterial agents in yeast fermentation processes. A phage cocktail was applied to control contamination while preventing the development of bacterial resistance. The study identifies and quantifies the effects of parameters influencing infection/contamination. The data obtained were ultimately used to develop a mathematical model detailing the dynamics of the populations involved (yeasts, bacteria and phages). The results showed that the addition of phages cocktail at relatively low initial multiplicity of infection was sufficient to reduce contamination and allowed the yields of yeast and ethanol to reach values equivalent to those of axenic yeast cultures. Moreover, the model showed good fit to the experimental results.

• Subjects / Keywords

  • Bacteriophages
  • Contaminants
  • Antimicrobials
  • Yeast fermentation
  • Phages
  • Biofuel
  • Ethanol

• Graduation date

  Fall 2013

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3CF9JF8G

• 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.