(716e) Engineering Strategies to Improve Cellulase Production: Trichoderma reesei as a Pellet
AIChE Annual Meeting
2013
2013 AIChE Annual Meeting
2013 International Congress on Energy (ICE)
Biochemical Conversion Processes in Forest/Plant Biomass Biorefineries I
Thursday, November 7, 2013 - 4:55pm to 5:20pm
In this study, we demonstrate the use of
surfactants and specific nutrient control to regulate the growth and behavior
of Trichoderma reesei Rut C-30. Although T. reesei is the
ubiquitous cellulase producing fungus, many practical engineering issues remain.
Typical processing conditions utilize a high growth density complicated with
high nutrient demand in a viscous filamentous biomass filled fluid phase. This
work shows that surfactants can be used to alleviate these processing
difficulties by leveraging the inherent cell biology to our advantage. Surfactants
have long been used to reduce cellular agglomeration, lyse cells, and improve
cellular membrane permeability. In fungal cultures the application the
surfactants tends to produce variable, species dependent, responses. In the
case of the normally filamentous T. reesei Rut C-30, certain surfactants
were found to promote growth into a compact pellet formation (diameter 1 ? 4
mm). These physical changes to the morphological structure have an overall
positive effect on fermentation, allowing for improved mixing and mass transport
through the continuous fluid phase. To improve yields and further decouple
cellulase production from the growth phase, the restriction of key nutrients
were tested. The specific control of phosphorus was found to successfully halt
cell growth without affecting cellulase production. These results indicate that
long-term cellulase can be continually produced from a pelleted, stationary
phase, T. reesei culture.
surfactants and specific nutrient control to regulate the growth and behavior
of Trichoderma reesei Rut C-30. Although T. reesei is the
ubiquitous cellulase producing fungus, many practical engineering issues remain.
Typical processing conditions utilize a high growth density complicated with
high nutrient demand in a viscous filamentous biomass filled fluid phase. This
work shows that surfactants can be used to alleviate these processing
difficulties by leveraging the inherent cell biology to our advantage. Surfactants
have long been used to reduce cellular agglomeration, lyse cells, and improve
cellular membrane permeability. In fungal cultures the application the
surfactants tends to produce variable, species dependent, responses. In the
case of the normally filamentous T. reesei Rut C-30, certain surfactants
were found to promote growth into a compact pellet formation (diameter 1 ? 4
mm). These physical changes to the morphological structure have an overall
positive effect on fermentation, allowing for improved mixing and mass transport
through the continuous fluid phase. To improve yields and further decouple
cellulase production from the growth phase, the restriction of key nutrients
were tested. The specific control of phosphorus was found to successfully halt
cell growth without affecting cellulase production. These results indicate that
long-term cellulase can be continually produced from a pelleted, stationary
phase, T. reesei culture.