Cellulase production through solid-state tray fermentation, and its use for bioethanol from sorghum stover

Area of Science:

• Biotechnology
• Enzyme Engineering
• Industrial Microbiology

Background:

• Cellulase enzymes are crucial for biomass conversion.
• Trichoderma reesei RUT C-30 is a well-established cellulase producer.
• Solid-state fermentation (SSF) offers advantages for enzyme production.

Purpose of the Study:

• To optimize cellulase production by Trichoderma reesei RUT C-30 using SSF.
• To evaluate the efficacy of the produced cellulase in hydrolyzing sorghum stover.
• To assess the subsequent conversion of hydrolysate to ethanol.

Main Methods:

• Utilized a two-stage statistical design of experiments for process optimization.
• Conducted solid-state fermentation on wheat bran and cellulose.
• Assessed enzyme activity (CMCase) and hydrolytic efficiency.
• Fermented enzymatic hydrolysate to produce ethanol.

Main Results:

• Achieved a 3.2-fold increase in CMCase production to 959.53 IU/gDS.
• Pilot-scale fermentation yielded 457 IU/gDS.
• Incorporation of Aspergillus niger β-glucosidase enhanced sorghum stover hydrolysis by 174%.
• Enzymatic hydrolysate was fermented to ethanol with approximately 80% efficiency.

Conclusions:

• Optimized SSF conditions significantly enhance cellulase production in Trichoderma reesei.
• The produced cellulase, supplemented with β-glucosidase, is effective for sorghum stover saccharification.
• The process demonstrates potential for efficient bioethanol production from lignocellulosic biomass.