Production of Bioethanol and Crude Cellulase Enzyme Extract from Napier Grass (Pennisetum purpureum S.) through Simultaneous Saccharification and Fermentation by Neurospora sitophila

• Main Author: (Nim : 11214021), Sherly
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/30928
• Institution: Institut Teknologi Bandung

Fossil fuel energy demand is increased however follows by rapid depletion of fossil reserves. To overcome this problem, national energy diversification is needed including enhance biofuel production. Napier grass is one of potential feedstock for bioethanol production. It contains high amonuts of cellulose and hemicellulose that can be hydrolysis to glucose. Glucose can be fermented into ethanol by microbe such as fungi. Neurospora sitophila has the ability to synthesize and secrete hydrolytic cellulase enzymes involved in cellulose hydrolysis and various enzymes to degrade hemicellulose and simultaneously convert various monomeric sugars into bioethanol. Their cellulolytic activity to degrade cellulose can be evaluated by activity enzyme. Crude cellulase activity and bioethanol production yield can be influenced by substrate concentration and fungi cultivation period. The present work investigates the influence of napier grass substrate concentration and on the crude cellulase activity and bioethanol production was evaluated. The alkaline pretreatment was optimized and carried out in erlenmeyer with NaoH solution 1,5% (w/v) for 120 hours at 30°C. After pretreatment process, simultaneous saccharification and fermentation was conducted at 30°C; pH 6,8-7,0 and agitation speed 130 rpm with various of napier grass substrate concentration (10, 20 and 30 g/L) and cultivation period within 24; 48; 72; 96 and 120 hours. The results shows that the highest enzyme activity is 0,28 FPU/ml occurred at 120 hours of cultivation and 20 g/L substrate concentration. Highest ethanol yield conducted at 0,30 g/g cellulose by 96 hours of fermentation.