Oil palm trunks are a possible lignocellulosic source for ethanol production. Low enzymatic digestibility
of this type of material (11.9% of the theoretical glucose yield) makes pretreatment necessary. An enzymatic
digestibility of 95.4% with insoluble solids recovery of 49.8% was achieved after soaking shredded
oil palm trunks in ammonia under optimum conditions (80 C, 1:12 solid-to-liquid ratio, 8 h and 7%
(w/w) ammonia solution). Treatment with 60 FPU of commercial cellulase (Accellerase 1000) per gram
of glucan and fermentation with Saccharomyces cerevisiae D5A resulted in an ethanol concentration of
13.3 g/L and an ethanol yield of 78.3% (based on the theoretical maximum) after 96 h. These results
indicate that oil palm trunks are a biomass feedstock that can be used for bio