Konferensartikel

Sweet sorghum (Sorghum bicolor L. Moench) is the potential raw material of ethanol production. As a lignocellulosic material; hydrolysis is needed to transform it to sugar. Usually; this sugar was used as substrate for ethanol production by fermentation. In this study; the composition of sweet sorghum bagasse was analyzed. The compositions of the sweet sorghum bagasse before hydrolysis are 58.23% cellulose; 25.42% hemicellulose and 14.95% lignin. It was then cut; dried and pretreated at 121 ^oC; 25 min by sodium hydroxide. Then the experimental design is performed to design the experimental runs. Box-Behnken was used to design the experiment of chemical hydrolysis. The factors of sulfuric acid concentration (15-55 %w/w); solid to liquid ratio (1:10-1:30 w:w) and reaction time (40-120 minutes) affecting reducing sugar production were optimized for the chemical hydrolysis. At the optimum condition; the maximum reducing sugar was equal to 33.49% (g/g dry substrate). On the other hand; microbial hydrolysis with Trichoderma harzianum gave the maximum reducing sugar of 10.34 % (g/g dry substrate) at optimum condition. Then type of reducing sugar was analyzed using High Performance Liquid Chromatography (HPLC). It is obvious that glucose is the dominated reducing sugar. Finally; the reducing sugar (glucose; xylose and arabinose) from chemical and microbial hydrolysis is usually fermented with Saccharomyces cerevisiae to produce ethanol.

Hydrolysis; Sweet Sorghum Bagasse; Ethanol; Trichoderma harzianum