Production of Bioethanol from Napier grass: Comparison in Pre-treatment and Fermentation Methods

Abstract

Bioethanol as alternative renewable energy can be derived from lignocellulosic biomass. One of the potential biomass that can be used for bioethanol is Napier grass (Pennisetum purpureum Schumach). Napier grass has a high content of cellulose which can be utilized as a substrate for fermentation process. A better understanding of bioconversion of Napier grass into bioethanol is essential for enhancing its performance. In this study, three biological agents were involved, Aspergillus niger and Phanerochaete chrysosporium for delignification and Neurospora sitophila for cellulase and bioethanol production in solid-state and submerged fermentation. Alkaline pretreatment using Ca(OH)2 and NaOH were conducted in this study. The result showed biological pretreatment using Aspergillus niger gave a higher delignification yield compared to alkaline pretreatment. For cellulase production, solid-state fermentation resulted in a higher enzyme activity compared to submerged fermentation and for bioethanol production, submerged fermentation yielded higher bioethanol compared to solid-state fermentation system but the difference was not too significant.