Monday, April 29, 2013
Exhibit Hall
Cashew apple bagasse (CAB) was pretreated using alkaline hydrogen peroxide at 35 °C for 6 hours using 4.3% v/v H2O2 concentration (pH 11.5) and 5% m/v biomass loading. The study of effect of the combination of four commercial enzyme were evaluated in digestion from CAB at 45°C, 150 rpm and pH 4.8 for 72 h. A combination of three commercial enzyme preparations (cellulase, hemicellulase and β-glucosidase) was found to maximize monomeric sugar release. In essence, yields of glucose, xylose, arabinose and cellobiose to 304, 73, 39 and 56 (mg/gCAB), respectively. After, the neutralized hydrolysis liquid were used in fermentation process with Kluyveromyces marxianus at 30 °C and 150 rpm. At this condition, 15.5 g/L ethanol was obtained. Also, the solid fraction obtained of pretreatment was used in the study of simultaneous enzymatic saccharification and fermentation (SSF). SSF was conducted using commercial enzymes cellulase (30 FPU/gcellulose) and cellobiase (60 UCB/gcellulose) by K. marxianus. Different biomass loading (1, 2, 2.5 and 5 gcellulose/100 ml medium) and temperature (40, 45 and 50°C) was evaluated. The optimal conditions for SSF were 40 °C, cellulose loading 30 FPU/g cellulose and 60 UCB/g cellulose, yeast inoculum 5 g/L and 2.5 gcellulose/100 mL of medium. Under the optimal conditions, the total ethanol concentration in SSF of CAB pretreated with AHP reached 8.3 g/L, this represented 73 % of the theoretical yield. Alkaline hydrogen peroxide is an effective pretreatment for cashew apple bagasse to ethanol production.