Bioconversion of cellulose into ethanol by nonisothermal simultaneous saccharification and fermentation

Area of Science:

• Biochemical Engineering
• Enzyme Kinetics
• Fermentation Technology

Background:

• Cellulase and beta-glucosidase kinetics are crucial for efficient biomass hydrolysis.
• Simultaneous saccharification and fermentation (SSF) systems require integrated models for optimization.
• Temperature significantly impacts yeast growth and ethanol production kinetics.

Purpose of the Study:

• To determine kinetic parameters for cellulase and beta-glucosidase during hydrolysis.
• To investigate the effects of temperature on yeast growth and ethanol production in SSF.
• To develop and optimize a nonisothermal temperature profile for maximizing ethanol yield.

Main Methods:

• Kinetic parameter estimation for cellulase and beta-glucosidase.
• Mathematical modeling and computer simulation of SSF processes.
• Experimental investigation of yeast growth and ethanol production under varying temperatures.

Main Results:

• Kinetic parameters accurately predicted experimental data for hydrolysis.
• A nonisothermal temperature profile (35°C to 39°C, then to 36°C) was developed.
• Maximum ethanol production reached 14.87 g/L using the optimized temperature profile.

Conclusions:

• Enzyme kinetic parameters are vital for SSF modeling and optimization.
• Dynamic temperature control in SSF significantly enhances ethanol production efficiency.
• The developed nonisothermal strategy offers a pathway to maximize bioethanol yields.