Optimization of Endoglucanase Production by Trichoderma harzianum KUC1716 and Enzymatic Hydrolysis of Lignocellulosic Biomass

Abstract

Trichoderma species are widely used for the commercial production of cellulolytic enzymes. In the present investigation, medium components were optimized using a central composite design and response surface methodology to produce endoglucanase (EG) from Trichoderma harzianum KUC1716. From the various medium components tested, cellulose, soy peptone, and thiamine HCl were selected as the optimal carbon, nitrogen, and vitamin sources, respectively. The highest EG (1.97 U/mL) production was obtained with 1.85% cellulose, 0.48% soy peptone, and 0.10% thiamine HCl. EG production in the optimized medium was 2.6 fold higher than in the unoptimized medium. In addition, the crude enzyme preparation from T. harzianum KUC1716 supplemented with β-glucosidase from Schizophyllum commune KUC9397 was used to hydrolyze various types of lignocellulosic materials and showed significant saccharification yields on all lignocellulosic materials, surpassing that of a commercial enzyme cocktail. It was verified that the crude enzyme preparation derived from T. harzianum KUC1716 could replace the commercial enzymes. This highlights the potential of the crude enzymes for use in biomass conversion systems.

Keywords

• Endoglucanase
• Optimization
• Response surface methodology
• Saccharification
• Trichoderma harzianum