7-80: Effect of delignification in the enzymatic hydrolysis of sugarcane bagasse cellulignin using cellulase from Trichoderma harzianum

The objective of this study was to evaluate the performance of the cellulasic preparation produced by Trichoderma harzianum on the enzymatic hydrolysis of sugarcane bagasse cellulignin at different degrees of delignification. Initially, the sugarcane bagasse was pretreated using 1% sulfuric acid solution to remove the hemicellulose. Then the concentrated enzymatic extract of T. harzianum was applied to the enzymatic hydrolysis of sugarcane bagasse cellulignin in different degrees of delignification (0.10%, 0.25%, 0.50%, 1%, 2% and 4% NaOH solution). The hydrolysis was performed with standard enzyme load of 25 FPU/g and substrate concentration of 100 g/L. The experiments were carried out in erlenmeyer flasks at 50°C under agitation of 200 rpm/72 hours. Glucose and total reducing sugars produced in the hydrolysis were quantified. The kinetics profiles of the hydrolysis were obtained every three hours. The results showed that the highest hydrolysis yields occurred in cellulignin delignified with 1%, 2% and 4% NaOH solution.  After 72 hours of hydrolysis, glucose concentrations were 13.87 g/L (0.1%), 14.74 g/L (0.25%), 22.00 g/L (0.50%), 27.67 g/L (1%), 28.14 g/L (2%) and 27.33 g/L (4%). The same profile was observed for reducing sugars: 20.89 g/L (0.1%), 24.28 g/L (0.25%), 32.15 g/L (0.50%), 38.33 g/L (1%), 38.08 g/L (2%) and 38.37 g/L (4%). It is concluded that deliginification using NaOH from 1% was sufficient in the enzymatic hydrolysis of sugarcane bagasse cellulignin using cellulase from Trichoderma harzianum.